m PUBLICATIONS OF SOWER, POTTS & CO., PHILADELPHIA. THE Normal Educational Series OF School and College Text-Books. " Every child that cones into the world has a right to an education." " The dearest interest of a nation "H the education of its children," The art of Teaching, as well as all other arts, is making very rapid progress in this very progressive age. The remarkable growth of Normal Schools, organized to instruct in the best methods of teaching, and employing as professors the most able and advanced educators in the country, has given an immense impetus to the ad- vancement of this most honorable and useful of professions, and almost revolutionized the whole art of teaching. These great changes create a necessity for text-books adapted to them, and the publishers of the above series have taken great pains to meet this necessity. By the aid of their improved text-books, the work of the school-room, instead of being a drudgery, becomes pleasant to teachers and pupils, and they as well as parents are delighted with the rapid progress made with them. Raub's Normal Primary Speller. Raub's Normal Speller. BY PROF. A. N. RAUB, PRINCIPAL OF PENNSYLVANIA CENTKAL NORMAL SCHOOL, LOCK HAVEN. These elementary works are admirably arranged and classified. Simple and easy, yet logical and comprehensive, they never fail to make ready and correct spellers. Fewsmith's Elementary Grammar. Fewsmith's Grammar of Eng. Language. BY WM. FEWSM1TH, A.M., AND EDGAR A. SINGER. The uniform testimony of teachers who have introduced these grammars is, that they have been m»st agreeably surprised at their effects upon pupils. They are easy to understand by the youngest pupil, and the lessons before dreaded become a delight to teacher and pupils. Ex- traordinary care has been taken in grading every lesson, modeling rules and definitions after a definite and uniform plan, and making every word and sentence an example of grammati- cal accuracy. They only need a trial to supersede all others. Cornell University Library eometr arV19506 The normal elemental 3 1924 031 267 150 olin.anx Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31 924031 2671 50 THE NORMAL ELEMENTARY GEOMETRY: £MBRACING A BRIEF TREATISE ON icitsuraEtrtt anlr wn$onomctt$. DESIGNED FOR ACADEMIES. SEMINARIES, HIGH SCHOOLS, NORMAL SCHOOLS, AND ADVANCED CLASSES IN COMMON SCHOOLS. Eevised Edition, by EDWAKD BROOKS, A.M., Ph.D., LATH PRINCIPAL OF STATE NORMAL~"sCHOOL PENNSYLVANIA, AND AUTHOR OF THE NORMAL PRIMARY ARITHMETIC, NORMAL MENTAL ARITHMETIC, NORMAL WRITTEN ARITHMETIC, NORMAL UNION ARITHMETIC, PHILOSOPHY OF ARITHMETIC, METHODS OF TEACHING, MENTAL SCIENCE AND CULTURE, ETC. PHILADELPHIA: SOWER, POTTS & CO., 630 MARKET ST., and 523 MINOR ST. ® 1" ' IOt F I T / BFE; then will AB be greater than BE. For, at the point G make" the angle BGG = EFD, make C(x = FB, and draw !?(?; then will the triangle ■*' GGB equal BFE and &.B equal BE (Th. VI.). Draw. OX", bisecting the angle A GH, and draw also GK ; the two triangles AGK and XOG 1 are equal (Th. VI.), &n&AK= KG. Now, KG-\-KB> GB; hence AK + 7t5, or J..B, is greater than 6rj? or its equal BE. The same demonstration will apply when the point G falls within AB. If it falls on AB, the theorem is true by A. 7. Cor. The converse of this theorem is also true. THEOREM IX. If two triangles have the three sides of the one equal to the, three sides of the other, each to each, the triangles will be equal in all their parts. Let ABC and BEF be two triangles, having AB equal to BE, A G to BF, and BG to EF; then will the triangles be equal in all their parts. For, since AG and AB are respectively equal to BF and BE, if the angle A were greater than B, BG would be greater than EF (Th. VIII.) ; and if .1 were less than B, BG would be less than EF, for the same reason. But BG is equal to EF, therefore the angle A must be equal to B. 3(j GEOMETRY. In the same way it may be shown that the angle G equal* F, and the angle B equals E. Therefore, etc. THEOREM X. In an isosceles triangle the angles opposite the equal sides an equal. . Let ABO be an isosceles triangle, having the side A equal to the side B 0; then will the angle A be equal to the angle B. Join the vertex and the middle point of the base ABj then in the two triangles ADG and GDB, AG equals BG, DC is common, and AD equals DB; hence, the two triangles are equal in all their parts (Th. IX.), and the angle A is equal to the angle B. Cor. 1. A line drawn from the vertex of an isosceles tri- angle to the middle point of the base, bisects the vertical angle and is perpendicular to the base ; also, a line bisecting the vertical angle is perpendicular to the base and bisects it ; also, a line drawn from the vertex perpendicular to the base bisects both the base and the vertical angle. Cor. 2. Hence, also, an equilateral triangle is equian gular ; that is, it has all its angles equal. THEOREM XI. Conversely. — If two angles of a triangle are equal, the sid<% opposite them are also equal, and the triangle is isosceles. Let ABO be a triangle, having the angle A equal to the angle B; then will the side AC be equal to BG. For, if AG and OB are not equal, sup- pose one of them, as A 0, to be the greater. Then, take AD equal to BO, and draw DB. How. in the triangles ABO and ABD, we have the side A Z? BOOK I. 37 equal to BC, by construction, the side AB common, and the included angle ABC equal to the included angle DAB, by hypothesis; hence, the two triangles ABB and ABC are equal (Th. VI.) ; that is, a part equal to the whole, which is impossible (A. 7). Hence, the hypothesiB that A C and BC are unequal is false ; therefore, they are equal, and the triangle is isosceles. Therefore, etc. THEOREM XII. In any triangle the greater side is opposite the greater angle, and, conversely, the greater angle is opposite the greater side. In the triangle ABC, let the angle ABC be greater than CAB; then will A C be greater than BC. For, draw BD, making the angle ABD = BAB; then will AB = BB (Th. XI.). To. each add BC and we have AB + BC= BB + BC; but BB + B C > B C (A. 10) ; hence, AB + BC,orAC,is greater than BC. Conversely. Let the side A C> BC; then will the angle ABC> CAB. For, if ABC < CAB, AC ^ AB be equal to DC, and AD to BG. / \ / For, draw the diagonal DB. Then, since / \/ AB and DC 'are parallel, the alternate an- gles ABD and BDG are equal (Th. III.) ; and since AD and 40 GEOMETRY. BG are parallel, the alternate angles ADB and DBG ar& equal. Hence, the two triangles ABB and DBG have two angles and the included side, DB, of one, equal to two angles and the included side, DB, of the other, each to each; therefore, the triangles are equal (Th.VIL); and the side AB opposite the angle ADB is equal to the side DG opposite the equal angle DBG: hence, also, the side AD equals BG; therefore, the opposite sides of a parallel- ogram are equal. Again, since the triangles are equal, the angle A is equal to the angle G; and the angle ADG, which is made up of the two angles ADB and BDG, is equal to the angle ABG, which is made up of the equal angles DBG and ABD- Therefore, etc. Cor. 1. The diagonal divides the parallelogram into two equal triangles. Cor. 2. Two parallels included between two other paral- lels are equal. Gor. 3. Two parallelograms are equal when they have two sides and the included angle of one, equal to two sides and included angle of the other. THEOREM XVI. If the opposite sides of a quadrilateral are equal, each to each, the equal sides are parallel, and the figure is a parallelogram. TjetABGD be a quadrilateral, in which AB equals DG, and AD equals BG; then will it be a parallelogram. For, draw the diagonal DB. Then the triangles ABD and DBCh&re all the sides of the one equal to all the sides of the other, each to each ; therefore the two triangles are equal (Th. IX.") ; and the BOOK I. 41 angle ABB opposite the side AB is equal to the angle BBC opposite the equal side B C; therefore, the side AB is paral- lel to the side DG (Th. IV.)- For a like reason, AB is parallel to BC; therefore, the figure ABCB is a* paral- lelogram. Therefore, etc. THEOREM XVII. If two sides of a quadrilateral are equal and parallel, the figure is a parallelogram. , Let ABCB be a quadrilateral, having the sides AB and BO equal and parallel ; then will ABCB be a parallelogram. For, draw the diagonal BB. Then, since AB is parallel to BO, the alternate angles ABB and BBC are equal (Th. III.). Now, the triangles ABB and BBC have the side AB equal to BC, by hypo- thesis, the side BB common, and the included angles ABB and BBC equal ; hence, the triangles are equal (Th. VI.), and the alternate angles ABB and BBC are equal ; hence, the sides AB and BC are parallel (Th. IV.), and the figure is a parallelogram. Therefore, etc. THEOREM XVIII. The diagc nals of a parallelogram bisect each other ; that is, divide each other into equal parts. Let ABCB be a parallelogram, and^C %_ and BB its diagonals ; then will AH be equal to EG, and BE to EB. For, since AB and BC are parallel, the A B angle CBE equals ABE (Th. III.); and also BCE equals EAB; and since AB equals BC, the triangles AEB and BEC have two angles and the included side of the one 4* 42 GEOMETRY. equal to two angles and the included side of the other, hence, the triangles are equal (Th. VII.), AE equals CE, and DE equals BE; therefore, the diagonals are bisected at E. ANGLES OF POLYGONS. THEOREM XIX. If each side of a convex polygon be produced so as to form one exterior angle at each vertex, the sum of the exterior angles will be equal to four right angles. Let ABCDEF be a convex polygon, with each side pro- duced so as to form one exterior angle at each vertex; then will the sum of the ex- terior angles be equal to four right angles. For, from any point within the polygon, draw lines respectively parallel to the sides of the polygon ; the angles contained by the lines about this point will be equal to the exterior angles of the polygon (Th. V.). But the sum of the angles formed about a point equals four right angles (Th. II. C. 2) ; hence, the sum of the exterior angles of a polygon equals four right angles. Therefore, etc. Cor. 1. The sum of the interior angles of a polygon is equal to twice as many right angles as the polygon has sides, less four right angles. The sum of each exterior and interior angle equals two right angles, and there are as many of each as the polygon has sides ; hence, the sum of all the exterior and interior angles equals two right angles taken as many times as there are sides of the polygon. But the sum of the exterior angles equals BOOK I. 43 four right angles ; hence, the sum of the interior angles equals two right angles taken as many times as the poly- gon has sides, minus four right angles. Cor. 2. The sum of- the interior angles of a quadrilateral equals 2 right angles multiplied by 4, minus 4 right angles, which is 8 — 4, or 4 right angles. In a rectangle each angle is a right angle. Cor. 3. The sum of tne angles of a pentagon equals 2 X 5 — 4 = 6 right angles. Each angle of an equiangular pen- tagon is i of 6 or f of a right angle, or 108°. Cor. 4. The sum of the angles of a hexagon equals 2 X 6 — 4 = 8 right angles. Each angle of an equiangular hexagon is | of a right angle, or 120°. Cor. 5. In polygons of the same number of sides, the sum of the angles is the same. In equiangular polygons, each angle equals the sum -divided by the number of sides. Scholium. This theorem is true at whichever extremity the sides are produced. PRACTICAL EXAMPLES. A common deficiency of pupils in the study of Geometry, is their inability to make a practical application of their knowledge. To remedy this, practical examples should be given, either in connection with the theorems or at the close of each book. The following problems may be used in either of these ways which the teacher may prefer. 1. If one line meet another line at an angle of 60°, what is the value of the adjacent angle ? Solution. — If the line DC meets AB, making the angle BOB equal to 60°, the angle AOD will equal 180 o _ 60°, or 120°, since ACV+DCB=180°. J 2. If two lines me«t a third at the same point, making angles equal to 30° and 80° respectively, required the angle between the two lines. 44 GEOMETRY. 3. How many degrees in each angle of a rectangle '' 4. How many degrees in each angle of an equilateral triangle ? 5. If two angles of a triangle are 43° and 75° respectively, what is the other angle ? 6. If two angles of a triangle are each 45°, what is the other angle, and what is the kind of triangle ? 7. If one angle of a triangle is 60°, what is each of the other two., if equal, and what is the kind of triangle ? 8. If one of the two equal angles of a triangle is 30°, what is each of the other angles ? 9. Required the number of degrees in each angle of an equiangular pentagon. 10. Required the number of degrees in each angle of an equiangular hexagon. 11. In a triangle whose angles are A, B, C, what is each angle if A is twice and B three times C? 12. In the preceding problem, what is the kind of triangle ? 13. Required each angle of an isosceles triangle, if the unequal angle equals twice the sum of the other two. 14. Required the value of each exterior angle of an equiangular octagon. EXERCISES FOR ORIGINAL THOUGHT. We now give some theorems to exercise the pupil in original thought The importance of such exercises cannot be overestimated. Much of the discipline of Geometry is lost by the pupil memorizing the demon- strations given in the book. One can become a good- geometer only by trying his powers with new theorems and problems, and endeavoring to find out demonstrations and solutions for himself. These theorems may be given upon review, one of them in connection with the regular lesson ; or, if the teacher prefer, the lesson may consist wholly of them. With classes whose time for the study is limited, they may be omitted. 1. If the equal sides of an isosceles triangle be produced, the two obtuse angles below the base will be equal. BOOK I. 45 2. If the three sides of an equilateral triangle be produced, all the external- acute angles will be equal, and all the obtuse angles will be equal. 3. Either side of a triangle is greater than the difference between the other two. 4. If a line be drawn bisecting an angle, any point of the bisecting line is equally distant from the sides of the angle. 5. Prove that the diagonals of a rectangle are equal. 6. If the diagonals of a quadrilateral bisect each other at right angles, the figure is a rhombus or square. 7. If a line joining two parallels be bisected, any other line through the point of bisection and joining the two parallels, is also bisected at that point. 8. If from any point within a triangle, two straight lines be drawnto the extremities of any side, their sum will be less than the sum of the other two sides of the triangle. 9. If a line is perpendicular to another line at its middle point, — . 1. Any point in the perpendicular will be equally distant from the ex treraities. 2. Any point out of the perpendicular will be unequally dis- tant from the extremities. BOOK II. RATIO AND PROPORTION. 1. All reasoning is by comparison. In comparing two quantities, we see that they bear a certain relation to each other. 2. Eatio is the measure of the relation of two similar quantities. It is found by dividing the first by the second; thus, the ratio of 8 to 4 is |, or 2, the ratio of A to B is — 3. The two quantities compared are called the Terms of the ratio. The first is called the Antecedent, the second the Consequent, and the two constitute a CoicpleL 4. A ratio is indicated by placing a colon between the quantities, or by writing the consequent under the ante- cedent, as in division ; thus, the ratio of A to B is written, A: B, or-. B 5. A Proportion is an expression of equality between equal ratios ; thus, the ratio of 8 to 4 equals the ratio of 6 to 3, and a formal comparison of these, as 8 : 4 = 6 : 3, is a proportion. 6. The equality of ratios is usually indicated by a double colon ; thus, 8 : 4 : : 6 : 3. This is read, the ratio of 8 to 4 equals the ratio of 6 to 3, or, 8 is to 4 as 6 is to 3. - 7. There are four terms in a proportion ; the first and fourth are called the extremes; the second and thirdj the 46 BOOK II. 47 means. The first and second together are the first couplet'; the third and fourth, the second cotivlet 8. Quantities are m proportion by Alternation, when ante- cedent is compared with antecedent, and consequent with consequent ; thus, if A : B : : C: D, by alternation we have A : 0: : B : D. 9. XJ uail tities are in proportion by Inversion, when the antecedents are made consequents and the consequents antecedents ; thus, if A : B : : G : D, by inversion we have B : A : : B : 0. 10. Quantities are in proportion by Composition, when the sum of antecedent and consequent is compared with either antecedent or consequent ; thus, if A : B : : 0:D, by com- position we have, A : A -\- B : : C: C -\- D. 11. Quantities are in proportion by Division, when the difference of antecedent and consequent is compared with either antecedent or consequent ; thus, if A : B : : G:D, we have, A: A - B : : C-.G—D. . A Continued Proportion is a series of equal ratios; as, A: B::C;D:;E;F::, etc. Analysis.— The object of the theorems of this book is to derive the principles of proportion. These principles are employed in the books which follow. The method consists in regarding .a proportion as an equation, which it really is, — an equality of ratios. Thus, the pupil 'should be taught to regard the proportion^! : B: : C: D as equivalent to A -+- B =C-j- D, and as'soon as this idea is clearly fixed in the mind the subject becomes simple and easy. The first proportion is the basis of demonstration for the others, and may be used as a test of the truth of all others. 48 GEOMETRY. THEOREM I. If four quantities are in proportion, the product of the means will equal the product of the extremes. Take the proportion A: B :: G: D; then we wish to prove ihat 1XD = ^X G. For, from the proportion we have A C b = 3 ; multi P 1 y in s bv B x -A we have, Ay^D = BX G. Therefore; if four quantities are, etc. THEOREM II. If the product of two quantities equals the product of two other quantities, the quantities forming one product may be made the means, and the other two the extremes of a proportion. Suppose we have A X D = B X 6; dividing by B X B, A G we have, ~f> = Y>> pl acm g this i n another form, we have, A: B : : G:D. Therefore, etc. THEOREM III. A mean proportional between two quantities equals the square root of their product. Let j? be a mean proportional between A and G; then we have, A : B : : B : G; whence (Th. I.), B* = AxC, or, B = y/AxG. Therefore, etc. BOOK II. 49 THEOREM IV, If four quantities are in proportion, they will be in proportion by alternation. Suppose A:B::G:D; from this (Th. I.) we have, A X D = -B X G; dividing by D X G, we have, 7y— 7i> whence, A:G::B:D. Therefore, etc. Remark. — The proposition is evidently true, since we have the same products when we take the product of the means and extremes as before the change. This principle may he applied to several other propositions. THEOREM V. If four quantities are in proportion, they will, be in proportion by inversion. > Suppose A : B : : G : D; from this we have, — =r— ; taking the reciprocal, we have, — = — ; whence, B : A : : D : G. Therefore, etc. THEOREM VI. If four quantities are in proportion, they will be in proportion by composition. Suppose A : B : : G: D; then A we have, •5 = "n- Adding qne to each A G we have, — + 1 = ■= + 1 ; reducing to a common denomi- 50 GEOMETRY. , A + B C+D , nator, we have, — B — = — '=■ — ; whence, B JJ A + B: B:: C+D: D. Therefore, etc. THEOREM VII. If four quantities are in proportion, they will be in proport, * by division. Suppose A: B :: C: D; then we have, — = — ; subtracting 1; A C we have, — — \ = -= — 1 ; reducing, A—B C—D we have, = — = — =■ — ; whence, A — B:B:: C— D : D. Therefore, etc. THEOREM VIII. JQF two proportions have a couplet in each the same, the other couplets will form a proportion. Suppose A : B : : C: D; and A: B::H:F;. then, . A C ,A B , .. _ B = -p and -^ = - ; hence (A. 1), 5 = |? ; whence C : D ::E: F. JJ Jf Cor. If two proportions have a couplet in each proportional, the other couplets will form a proportion. THEOREM IX. Equimultiples of two quantities are proportional to the quan- tities themselves. Let A and B be any two quantities ; then A A j} = ~j>; multiply both terms of the first by m, BOOK II. 51 , mA A . we nave, — n^ - ^; whence, mB B mA:mB::A:B. Therefore, etc. THEOREM X. If four quantities are in proportion, any equimultiples of the first couplet will be proportional to any equimultiples of the second couplet. Suppose A: B :: Q:D; then — =. =: ; hence, also, B JJ , mA nC . we have, — = — -^- ; whence mB nD we have, mA:mB::nC:nD. Therefore, etc. THEOREM XI. The products of the corresponding terms of two or more propor- tions are proportional. Suppose A : B : : G: B, and M-.N-.P: Q; then we have, iX-D = -BX G, MX Q = N X Pj taking their product, we have, A X M X & X Q = B X NX X P; whence (Th. II.) we have, A X M : B XN: : Cx P-D X Q. THEOREM XII. In any continued proportion, any antecedent will be to its consequent as the sum of the antecedents is to the sum of the consequents. Let A :B::C:D::E:F, etc. Then, since A : B : : C : D, and 52 GEOMETRY. A: B:: E: F ; we have Ay.D = BX C, and 4XJ ? =-BX-E; adding to these, A X B = ^. X -B, we have, -4 X -B + A X -D + A X -F = A X -B + B X C+ 5 X E, or, ix(i + 2) + J)=21(l+0+J)i tvhence, 4 : B: :A+ C+JE: B + D + F. PKACTICAL EXEKCISES. 1. If the first three terms of a proportion are 12, 14, and 18, what ia the fourth term ? Ans. 21. 2. Given the proportion 3 : 12 : : 5 : 20 ; what proportion have we by composition ? 8. Find a mean proportional to 12 and 27 ; to m and n. Ans. 18 ; ^/m X n. 4. If the ratio of A to B is $ , what is the ratio of 3 A to 2 B ? Ans. |. 5. If the ratio of 3 A to 2 Z? is f , what is the ratio of ^1 to £ ? ^4n«. J. 6. What proportion is deducible from the equation M X iV= A 2 — B\ Ans. M:A + B::A — B:N. 7. What proportion is deducible from the equation ( C -|- Z)) X -^ = ( L A + B)XC* Ans.A:B::C:D THEOREMS FOR ORIGINAL THOUGHT. 1. If a : I : : c : d, prove that am : bn: : cm: dn. 2. If a : b : : c : d, prove that — :-::—:-. m n m n 3. If a : b : : c : d, prove that a: a -\- b : : c: c -\- d. 4. If a : b : : c : d, prove that a -\-b : a — b: : c -\- d: c — d. 5. If a : b : : c : d and m : c : : n : d, prove that a : b : : m : n. BOOK III. AREAS AND RELATIONS OF POLYGONS. 1. This book treats of the area of polygons and then relation to each other. 2.. The Area of a polygon is its quantity of surface : it is expressed by the number of times which the polygon contains some other area assumed as a unit of measure. 3. The Altitude or a Triangle is ' the perpendicular distance from the vertex of either angle to ,the opposite side, or the opposite side produced. The vertex of the angle from which the altitude is drawn is called the vertex of the Triangle; the opposite side is called the base of the triangle. 4. The Altitude of a Parallelogram is the per- pendicular distance between two opposite sides. These opposite sides are called bases, one is the upper base, the other the lower base, i 5. The Altitude of a Trapezoid is the perpendicular distance between its i parallel sides. / These sides are called bases; one is called the upper base, the other the lower base. 6. Similar Polygons are those which are mutually equiangular, and in which the corresponding sides are pro- portional. 5* 53 54 GEOMETRY. Corresponding sides or angles are those which are like placed. They are sometimes called homologous. 7. Equivalent Polygons are those which are equal in area. Polygons which, being applied to each other, coincide throughout their whole extent, are said to be equal in all their parts, or simply equal. The term equal is often used in geometry for equivalent meaning equal in area. The sign of equality, =, is used in comparing equivalent figures, and is read " equals," or " is equal to." 8. A Kegclab, Polygon is a polygon which is both equilateral and equiangular. Analysis. — The first object of this book is to find the area of poly- gons. It begins with the area of a rectangle, assuming as a unit of measure a square whose side is a measure of the sides of the given rectangle. From the area of the rectangle we pass to tha area of any parallelogram, thence to the area of a triangle, and from this to the area of any plane figure. The book also treats of the relations of the squares on the sides of triangles, and the relation of the angles, sides, and area of similar poly- gons, to each other. It is one of the most interesting and practical books of Geometry. BOOK III. 55 E AREA OF POLYGONS. THEOREM I. The area of a rectangle is equal to the product of its base and altitude. ' Let ABGB bo a rectangle ; then will its area be equalto the product of its base and altitude. For, let the line AB be a unit of measure of the base and altitude, and suppose it contained any number as 5 times in the base and 3 times in the A B altitude ; then, divide AB into 5 equal parts and AB into 3 equal parts, and through the points of division draw lines parallel, respectively, to the sides AB and AD; then will the rectangle be divided into equal , squares. For, their sides are equal (B. I. Th. XV. 0. 2) ; their angles are right (B. I. Th. III.); hence, the figures are equal squares (B. I. Th. XV. C. 3). Now, the whole number of these squares is equal to the number in one row multiplied by the number of rows, which is the same as the number of. linear units in the base multiplied by .the number of linear units in the alti- tude ; and the same is evidently true for any other numbers than 3 and 5. Hence, the area of ABGB equals AB X AB. Since this is true when the linear unit of measure is any length, it is true when it becomes exceedingly small, and is, therefore, true when it becomes infinitely small, as it must when the two sides are incommensurable. There 56 GEOMETRY. fore, the area of a rectangle is equal to the product of its base and altitude. Cor. 1. Bectangles are to each other as the products of their bases and altitudes. For, let AB and AD represent the base and altitude of one rectangle, and EF and EH the base and altitude of another ; then we will have the iden- tical proportion, ABOD : EFGH: :i£x^: EF X EH. Cor. 2. Bectangles having equal bases are to each other as their altitudes. For, suppose the bases AB and EF equal ; then, cancelling the equal factor in the second couplet, we have, ABCD : EFGH: : AB : EH. Cor. 3. Bectangles having equal altitudes are to each other as their bases. For, suppose the altitudes AB and EH are equal ; then, by cancelling the equal factor in the second couplet of Cor. 1, we have, ABCB : EFGH: : AB : EF. THEOREM II. The area of a parallelogram is equal to the product of its base and altitude. lietABCDbe a parallelogram, AB its base, and EB its altitude ; then will its area be equal to For, at the points A and B draw the ' 7 two ^perpendiculars AF and BE, and com- / plete the rectangle ABEF. Then, the £ - angle AD F equals the angle BCE, and FAB equals CBE (B. I. Th. V.); hence, the two triangles are equal (B. I. Th. VII.) ; therefore, ABEB + BCE is equal to ABED -\- ADF, or the parallelogram ABCD is equal to the rectangle ABEF. But the area of the rectangle is equal to AB X -B-®; hence, the area of the parallelogram is equal to AB X SE. Therefore, etc. BOOK III. 57 Cor. 1. Parallelograms are to each, other as the products of their bases and altitudes^ Cor. 2. Parallelograms having equal altitudes are to each other as their bases ; and parallelograms having equal bases are to each other as their altitudes. THEOREM III. The area of a triangle is equal to half the product of its base and, altitude. Let ABC be a triangle, AB its base, and CD its altitude ; then will its area be equal to half the product of its base and altitude. For, draw BE parallel to AC, and CE parallel to AB, completing the parallelogram ABEC ; then will the triangle A B C be one-half the paral- lelogram ABEC (B. I. Tfi. XV. C. 1). But the area of the parallelogram is equal to AB X CD; hence, the area of the triangle is equal to £ AB X CD. Therefore, etc. Cor. 1. Triangles are to each other as the products of their bases and altitudes. Cor. 2. Triangles having equal altitudes are as their bases ; having equal bases, they are as their altitudes. THEOREM IV. The area of a trapezoid is equal to one-half the sum of th6 parallel sides multiplied by the altitude. Let ABCD be a trapezoid, A B and DC its parallel sides, and DE its altitude ; then will its area equal \ (AP 4- DC) XDE. 58 GEOM-ETRY. For, draw the diagonal AG, dividing the trapezoid into the two triangles Ai? (7 and ADO, the altitude of each being DE. The area of ABO is, \AB X DE, the area of ABO is ^ DC X DE; hence, the area of ABCB, the sum of these triangles, is ^ABxDE plus ^BGX DE, which is £ (AB + DC) X DE. Therefore, etc. H SQUARES ON LINES. THEOREM V. The square described on the sum of any two lines is equal to the sum of the squares described on the lines, plus twice the rectangle of the lines. Let JL.Bandr.BObe two lines, and AG their sum ; then will AC 1 = AB* + BC* + 2 AB X BO. ForjOn^ construct the square A CFD and on AB construct the square ABHG; prolong BH to E and GH to I. Now, it is readily seen that HIFE is the square of BO, also that BCIH equals the rectangle on AB and BC, and GHED equals the rectangle on AB and BO; therefore, the square A CFD consists of the square on the two lines plus twice the rectangle of the two lines. Cor. 1. The square of the difference of two lines equals the sum of the squares of the lines, minus twice the rectangle of the lines. For, construct a square on A C and on AB, prolong BH to E and HG to N, making GN=BC, and con- S B BOOK III. 59 ■T D A B K EC\ atruct the square GM ; then the rectangles BF and Hit are each equal to A C X B 0. Now, A CFD + NGDM— B GFE — HEMN==ABHG; or, A~C 2 + B~C~* — 1AC X BC= A~B\ Cor. 2. The rectangle contained by the sum and difference oj two lines equals the difference of their squares. For, construct a square on AB and on AC, take BK = BC, and construct the rectangle AL ; then AK=AB + BC, AC=AB — B C, BKLI = D GFE, and AXLE = {AB + BC) {AS — BC). ' Now, AKLE = ABIE + DF, which equals ABHF— DIHG; hence, (AB + BC)(AB — BC) = A~B> ■ THEOREM VI. The square described on the hypothenuse of a right-angled tri- angle is equal to the sum of the squares described on the other two sides. Let ABC be a triangle, right-angled at B; then will 4C* = AB* + BC\ For, construct squares on each of the sides, draw BD parallel to AF and produce it to E, and draw B £ the diagonals BF and HC. The two triangles HA C and BAF are equal; for, AC equals A F, being sides of the same square, HA equals AB, for the same reason, and the angle HAC equals the angle BAF, both being equal to a right angle -plus BA C; hence, the triangle HA C equals BAF. The triangle BAF is one-half of the rectangle AFED, Since it has the same base and the same altitude (Th. III.) J 60 GEOMETRY. also, since IB is a straight line, the triangle HAG and square ABIH have the same altitude ; hence, the triangle is one-half of the square (Th. III.). But these two trian- ' gles BAF and HAG are equal ; hence, the rectangle AFEB is equal to the square ABIH. In the same manner we may prove that the rectangle EGGD is equal to the square BCLK; hence, the sum of the two rectangles, or the square on AG is equal to the sum of the two squares HB and BL. Therefore, etc. Cor. 1. The square of either side about the right angle is equal to the square of the hypothenuse diminished by the square of the other side. For, since AB 2 + BG 2 = AC 2 , we have, by transposing, AB 2 = AC 2 — BG 2 . Cor. 2. The square of the diagonal of a square is equal to twice the square of the side of the square. Let ABCD be a square, then will AC 2 = 2 AB 2 . For, we have, by the theorem, A G 2 = AB 2 + BC 2 ; but AB 2 equals TfG 2 ; hence, by substitution, we have AG 2 = AB 2 -f AB 2 , or, AC 2 = 2AB\ Cor. 3. The side of a square is to its diagonal as 1 is to the square root of 2. For, since 2 AB 2 = AC 2 , or, 2 X AB 2 = AC 2 X 1, we have the proportion (B. II. Th. II.), AB 3 : AC 2 :: 1:2; extracting the square root, we have, AB : AC: : 1 : y'2. Cor. 4. Two rightrangkd triangles are equal in all their part* ■when they have two corresponding sides respectively equal. Note. — This is the celebrated Pythagorean proposition, so called because it was discovered by Pythagoras. It is also known as the 47th of Euclid that being its number in the first book of Euclid's Elements. BOOK III. 61 THEOREM VII. In any obtuse-angled triangle, the square of the side opposite the obtuse angle is equal to the sum of the squares of the other two sides, plus twice the product of the base into the distance from the vertex of the obtuse angle to the foot of the perpen-, dicular drawn from the vertex of the angle opposite the base to the bnse produced. Let ABC be a triangle, of which A is ail obtuse angle, AB its base, and CD the perpendicular drawn to the base produced ; then will BG* = AC* -f AB* + 2 AB X AD. For, in the right-angled -triangle DBG, we have, BO 2 = DC* + DB* ; but. DB =AB +AD; hence, DB' = AB" + AD* + 2ABX-AD (Th. V.). Hence, BO* = DO* -f AB* + AD* + 2ABxAD.^ But, DC + AD* = AC*. Hence, B 0* = AB* + AC* + 2 AB X AD. Cor. 1. If the angle CAB becomes a right angle, AB becomes zero, and we have, BC* = AB* -(- AC*- THEOREM VIII. In any triangle, the square of a side opposite an acute angle is equal to the sum of the squares of the other two sides, minus twice the product of the base and the distance from the vertex of the acute angle to the foot of the perpendicular let fall upon the base or the base produced. Let AB C be any triangle, B an acute .angle, il^its base, and CD the perpendicular; then will AC* = AB* + BC* — 2ABX BD. For, in the right-angled triangle ADC, ■ 62 GEOMETRY. we have, AC* = DC* + AD*; but AD =AB —DB; hence, AD* = AB* + DB* — 2ABX&B (Th. V. C. 1). Hence, AC* = DC* + AB* + DB' — 2 A.B X DB. But, i)© 2 -f DB* = BC*, in 5Z> C. c Hence, H? 2 =ZB 2 -f B~C* —2ABX DB. The same may also be shown if the per- pendicular meets the base produced, as in the second figure. Therefore, etc. Note.. — This 8th Proposition can be Tery prettily drawn from the 7th, by transposing the terms of the 7th, and reducing. Let the pupil try it. THEOREM IX. In any triangle, a straight line drawn parallel to the base divides the other sides proportionally. Let ABC he a triangle, and DE a line parallel to the base; then will CD :DA::CE: EB. For, draw AE and DB; then, since the two triangles ADE and DEC have their bases in the same line and their vertices at the same point E, they have the same altitude; hence, they are to each other as their bases (Th. III. C. 2), or, AED : DEC : : AD : DC. For a similar reason, the triangles BED and DEC are to each other as their bases ; hence, we have, BED : DEC : : BE : EC. But the triangles AED and BED have the same base DE and the same altitude, since their vertices are in the line (LB parallel to DE; hence, they are equal (Th. HI.), and BOOK III. 63 the two proportions have a couplet in each equal ; hence, the remaining terms are proportional (B. II. Th. Till.), and we have, AD: DC:: BE: EC. , Therefore, etc. Cor. 1. By composition, we have, AD + DC : AD : : BE + EC : BE, or, AC : AD :: BC : BE; and, in the same way, AC:DC::BC:EC. Cor. 2. Conversely, If a line divides two sides of a triangle proportionally, it will be parallel to the third side. Let DE divide CA and CB proportionally ; then, if DE is not parallel to AB, draw DE' parallel to AB. Now CA: CD:: ■CB : CE' (Cor. 1), but CA : CD : : CB : CE byhypothesis ; hence, CE' = CE, which is absurd. Therefore, etc. Cor. 3. Since DEC : AEC : : DC : AC and AEC : ABC: : EC-.BC, and also, DC : AC :: EC : BC; therefore, DEC : AEC : : AEC : ABC. That is, the triangle AEC is a mean proportional between DEC and ABC. SIMILAR. 'TRIANGLES. THEOEEM X. Triangles which are mutually equiangular are similar. Let ABC and DEF be two tri- angles having the angle A = D, the angle i?:=.&, and C=F; then will they be similar. For, on AC take CG- equal to FD, and on BC take CH equal to 61 GEOMETRY. FE, and draw GH; then the triangle GGH will be equal te FDE (B. I. Th. VI.) and the angle GGH will equal FDA; hence, the angle GGH equals GAB, and GH is parallel to AB (B. I. Th. IV.). Hence, we have (Th. IX. C. 1). AG: BO:: GO : HO, or,' AO:BO::DF:EF; and the same may be shown for the sides containing the other equal angles ; hence, the triangles are similar (D. 6). Therefore, etc. THEOREM XL Triangles which have their corresponding sides proportional are similar. Let ABC and DEF be two triangles having their cor- responding sides proportional; then will they be similar. For, if they are not similar, suppose some other triangle, as DEG, to be constructed upon the side DE, similar to ABC. Then, by the preceding the- orem, we have, AB:DE::AC:DG; but, by hypothesis, AB-.DE.-.AC: DF; hence, we have, DG=DF. In the same way, it may be shown that EG = EF. Hence, the triangles DEG and DEF must be equal in all their parts (B. I. Th. IX.), and, therefore, mutually equi angular; hence ABC and DEF are mutually equiangular. and, consequently, similar. Therefore, etc. BOOK III. _ 65 THEOREM XII. Triangles which have an angle in each equal, and the sides including them proportional, are similar. Let ABC and DEFbe two triangles having the angle G equal to the angle F, and AG:BG::DF: EF; then will the triangles be similar. For, apply the angle DFE to AGB, and the triangle DFE, will take the position GCH, and, from the proportion above, we shall have T b d e AO:BG::GG:HG; hence, GR is parallel to AB (Th. IX. C. 2), and the trian- gles OCH and ACB mutually equiangular, and therefore similar. But, GCH is equal to DFE; therefore, A CB and DFE are mutually equiangular, and similar. THEOREM XIII. Triangles which have their sides parallel, each to each, or per- pendicular, each to each, are similar. First. ~LetABC andDEF be two triangles having the side AB parallel to DE, A G parallel to DF, and GB parallel to FE; then will they be similar. For, sinceAC is parallel to DF and AB to DE, the angle A is equal to D (B. I. Th. V.) ; for a similar reason G is equal to F and B to E; hence, the triangles arc mutually equiangular, and, consequently, similar. Second. Let ABG and DEFbe two triangles having theit sides respectively perpendicular; then will they be similar, 66 GEOMETRY. For, produce the sides of DEF till they meet the sides of ABC. In the trapezium GEIC, the sum of the four angles equals four right angles (B. I. Th. XIX. C. 2), and since two of the angles are right angles, the sum of the angles C and GEI equals two right an- gles. But the sum of GEI and FED equals two right angles (B. I. Th. I.) ; hence, the angle FED equals the angle C. In the same way it may he shown that FDE equals B, and DFE equals A; hence, the two triangles are mutually equiangular, and, consequently, similar. Therefore, etc. THEOREM XIV. If, in a right-angled triangle, a line be drawn from the vertex of the right angle perpendicular to the hypothenuse ; 1. The two triangles thus formed will be similar to the given triangle and to each other. ' 2. Each side about the right angle will be a mean propor- tional between the hypothenuse and adjacent segment. 3. The perpendicular will be a mean proportional between th°, two segments of the hypothenuse. TietABC be a right-angled triangle, the right angle, and CD the perpendicular ; then, First. The triangles A CD and AB C have each a right angle, and the angle A common ; hence, the remaining angles are equal, and the triangles are similar (Th. X.). In the same manner, we show BCD and AB C equiangular and similar; and then ADC and BDC, being both similar to ABC, are similar to each other. BOOK III. 67 Second. The two triangles being similar to the given one, we have, AB: AC:: AC: AD, and also, AB:BC::BC: BD. Therefore, etc. Third. The two triangles being similar, we have, ' AD:DC::DC:DB, Therefore, etc. RELATION OF POLYGONS. THEOREM XV. Triangles which have an angle in each equal, are to each other as the products of the sides including those equal angles. Let ABC and DEF be two triangles having the angle F equal to the angle C; then will ABC : DEF ::ACXBC:DFXEF- For, place the angle F on its equal C, and the triangle DEF will take the place GCH; then draw-li?. Now, since the tri- angles ARC and QHC have their bases AC and GC in the same line A C, and vertices at H, they have the same altitude, and are to each other as their bases ; hence, AHC:GHC::AC:GC. Also, since AHC and ABC have their bases SC and BC in the same line, and vertices at the point A, they have the same altitude, and are as their bases ; hence, ABC:AHC::BC:HC; 68 - GEOMETRY. multiplying the corresponding terms of these two propor. tions together, and omitting the common factor AHC, we have, ABG : GHG ::AGxBG:GGxSO, or, ABG:DEF::AGXB0:DFXFH. Therefore, etc. THEOREM XVI. Similar triangles are to each other as the squares of their homologous sides. Let ABG and ABE be two similar triangles ; then will they be to each other as the squares of any two homolo- gous sides. Draw the alti- tudes AG and AF ; then, since the triangles are as the product of their bases and altitudes (Th. III. C. 1), we have, ABO : ADE: : BO X AG:DE X AF. But, by similar triangles, we have, BO:DE::AB:AD, and, AG:AF::AB:AD; hence, BO X AG: DE X AF ::AB*:AD*. Comparing this with the first proportion, we have, ABO:ADE::AB":AB\ F JB THEOREM XVII. Similar polygons may be divided into the same number of tri- angles, similar each to each, and similarly situated. Let AB ODE and FGSIKbe two sim ilar polygons, having the angle A equal to the angle F, B to G, OtoH, etc. ; then BOOK III. 69. can they be divided into the same number of similar tri- angles similarly situated. From tbe homologous angles A and F draw the diagonals AC, AD, and FH,F1. Since the poly- gons are similar, the tri- angles ABC and FGH have the angles B and G equal, and the sides about these an- gles proportional; they are, therefore, similar (Th. XII.). Since the triangles ABC and FGH are similar, the angle AGB equals FUG, and the sides AG and FH are propor- tional to BO and GH, and hence to CD and HI. If we take the equal angles A CB and FHG from the equal angles BCD and GHI, we have A CD equal to FHI; hence, the triangles ^ CD and .KHZ have an angle in each equal, and the sideu including these angles proportional ; they are, therefore, similar (Th. XII.). In a similar manner, it may be shown 'that ADE and FIK are similar. Therefore, etc. THEOREM XVIII. The perimeters of similar polygons are to each other as any two homologous sides) and the polygons are to each other as -the squares of those sides. lietABCDF and FGHIKbe two similar polygons; then will their perimeters be to each other as any two homologous sides,, and their areas be as the squares of those sides. First. Since the polygons are similar, we have* 70 GEOMETRY. AB.FG-.-.BG: GH: : CD : HI, etc. ; hence (B. II. Th. XII.), AB + BC + CD+ etc. : FG + GH+HI + etc. : :AB:FG; or, the perimeter of the first to the perimeter of the second as any side of the first to the homologous side'of the second. Second. Since the triangles are respectively similar, we have, ABG : FGH : :~AC* : FH*; and also, A CD : FH1 : : ~AC* : FH*; hence, we have, ABO : FGH ::AGD: FHI. In a similar manner, we find, AQD : FHI : : ADE : FIK. Hence (B. II. Th. XII.), the sum of the antecedents, ABG-{- ACD -j- ADE, is to the sum of the consequents, FGH-\- FHI -\- FIK, as any antecedent ABG is to its consequent - FGH; and, since ABG is to FGH as AB 2 to FG 3 , we have, ABCDE : FGHIK ::A&: FG 1 . Therefore, etc. Gor. The perimeters are to each other as any two homo- logous lines, and the polygons are as the squares of those lineB. THEOREM XIX. Regular polygons of the same number of sides are similar figures. Let ABGDEF and GHIKLM he two regular polygons of the same number of sides ; then will they be similar. j?or, the correspond- ing angles in each are equal (B. I. Th. XIX. C. 5), and the corresponding sides are proportional, since thoy BOOK III. 71 are equal; hence, the polygons are similar (D. 6). There fore, etc. Cor. Since regular polygons of the same number of sides are similar figures, their perimeters are proportional to any homologous lines, and their areas are as the squares of those lines. PRACTICAL EXAMPLES. 1. Required the perimeter and area of a square whose sides are each 20 inches. 2. Required the perimeter and area of a rectangle whose sidea are respectively 18 and 24 inches. 3. What is the area of a parallelogram whose base is 16 inches and altitude 12 inches ? 4. A man has a hoard in the form of a triangle ; what is its area if . the hase is 9 feet and the altitude 18 inches ? 5. A farmer has a field in the form of a trapezoid ; the two parallel sides are 40 and 60, rods, and the distance between them 32 rods ; re- quired its area. *6. Required the hypothenuse of a right-angle triangle, the two sides being 3 and 4 inches respectively. 7. The sides of a triangle are 18 and 21, and the base 24 ; what are the sides of a similar triangle whose base is 8 ? 8. A man had a lot in the form of a right-angle triangle ; the hypo- thenuse is 78 and one side 30 ; required the other side and the area. 9. A ladder 65 feet long is placed against a house, so that its foot is 25 feet from the house ; how high does it reach ? 10. A pole was broken 75 feet from the top, and fell so that the end struck 60 feet from the foot ; required the length of the pole. 11. A has a triangular piece of ground, the base of the triangle being * The numbers 3, 4, and 5 are the^emallest integers which can express the relation of the three sides of a right-angle triangle. It is evident that we may have an infinite number of right-angle triangles with their sides in this ratio. Thus, 6, 8, 10 ; '9-12, 15, etc. Another integral relation of sides' is 5, 12, 13. 72 GEOMETRY. 20 rods ; what is the base of a similarly-shaped lot containing 4 times.as much land ' Ans. 40 rods. 12. A man has a lot 40 rods long and 23 rods wide ; what are the dimensions of a. similar lot 9 times as large ? Ans. 120 ; 69. 13. A ladder, whose length is 91 feet, stands close against a building, how far must it be drawn out at the bottom that the top may be low- ered 7 feet? Ans. 35 feet. 14. A ladder 130 feet long, with its foot in the street, will reach on one side to a window 78 feet high, and on the other .to a window 50 feet high ; what is the width of the street ? Ans. 224 feet. 15. There is a rectangular field whose sides are 25 yards and 16 yards respectively ; what is the side of a square field of equal area ? Ans. 20 yards. 16. If it cost $328 to put a fence around a farm 50 rods long and 32 rods wide, how much less will it cost to enclose a square farm of equal area with the same kind of fence ? Ans. $8. 17. The gable ends of a house are each 48 feet wide, and the perpen- dicular height of the ridge above the eaves is 10 feet ; how many feet of boards will it take to board up both gables ? Ans. 480. 18. A man has a field in the form of a rectangle which contains 40 acres ; what are its dimensions if the length is twice the breadth ? Ans. Length, 113.136 rods; width, 56.568 rods. 19. A cemetery containing 60 acres is laid out in such a manner that its length is equal to three times its width ; required the dimensions of the cemetery. Ans. Length, 169.704 rods; width, 56.568 rods. 20. A general wishing to draw up his corps in the form of a square, found by the first trial he had 100 men over ; he then increased the side of the square by 2 men,, and found he lacked 136 men to complete the square ; how many men had he in the corps 1 Ans. 3464. 21. A man has a square yard containing ^ of an acre ; he makes a gravel walk around it which occupies £J of the whole yard ; what is the width of the walk ? Ans. 4 feet 1£ inches 22. In a triangle the two sides are 13 and 15, respectively, and the perpendicular from the vertex of the angle which they form to the op posite side, 12 ; required the third side. Ans. 14. BOOK III. 73 EXERCISES FOR ORIGINAL THOUGHT. 1. Two squares are to each other as the squares of their diagonals. 2. Two similar parallelograms are to each other as the squares of their diagonals 3. Prove that the diagonals of a rectangle are equal to each other. 4. Prove that the greater diagonal of a parallelogram is opposite the greater angle. 5. Show where a line from the vertex of a triangle must he drawn to divide the triangle into two equal parts. 6. Prove that the ratio of the side of a square to its diagonal is as 1 to the square root of 2. 7. The straight line joining the middle points of the oblique sides of a trapezoid will he parallel to the other sides, and equal to half their sum. 8. The four lines joining the middle points of the adjacent sides of a quadrilateral form a parallelogram. 9. The lines drawn from the vertices of the three angleB of an equi- lateral triangle, perpendicular to the opposite sides of the triangle, will intersect each other in the same point. 10. The line which bisects the vertical angle of a triangle divides the base into two parts which are proportional to the adjacent sides. 11. If a lin« be drawn parallel to the. base of a triangle, and lines be drawn from the vertex of the triangle to the base, these lines will divide the base and parallel proportionally. 12. Triangles which have an angle in each equal, are to each other &» the rectangles of the sides including those angles. BOOK IV. OF THE CIRCLE. DEFINITIONS. 1. ACiRCLEisa plane bounded by a curve line, eveiy point of which is equally distant from a point within, called the centre. 2. The Circumference is the bound- ing line of a circle. An Arc is any a[ part of the circumference; as, BD. 3. The Badius is a straight line drawn from the centre to any point of the circumferenc e ; thus, CD is a radius. 4. The Diameter is a straight line passing through the centre and terminating at both extremities in the cir- cumference ; as, AB. 5. A Chord is a straight line joining the extremities of an arc ; thus, BD is a chord. 6. A Segment is a portion of the circle included between an arc and its chord ; as, DBE. 7. A Sector is a portion of the circle included by an arc and the radii drawn to its extremities; as, DCBE. 8. ATANGENTisa straight line which touches the eh\ cumference in one point; thus, AB is a tangent. The point E is called the point of tangency. 74 BOOK IV- 75 9. A Secant is a straight line which cuts the circum- ference in two points ; thus, CD is a secant. 10. An Inscribed Angle is an angle whose vertex is in the cir- cumference and whose sides are chords ; as, ABO in the next figure. 11. An Inscribed Polygon is a polygon whose sides are chords, the vertices of the angles being in the cir- cumference; as, ABCDEF. 12. A Polygon is circumscribed about a circle when all of its sides are tangents to the circumference. The circle is at the same time inscribed in a polygon. AXIOMS. 1. The radii, and also the diameters, of a circle, or of equal circles, are equal. 2. Every diameter is double the radius, or is equal to the sum of two radii. 3. A straight line can cut a circumference in only two points. Analysis. — This book treats of the nature of the circle, the measure- ment of angles, the finding of the circumference, the measurement of the area of a circle, and the relation of the circumferences, and also »f the areas of circles. The method of treatment in finding the cir- iumference and area, and also their relations, is to regard the circle is a polygon of an infinite number of sides, and derive the principles from those of polygons. By a simplification of the subject, we embrace in one book what is usually given in two. 76 GEOMETEY NATURE OF THE CIRCLE. THEOEEM I. The diameter of a circle is greater than any other chord. Let AB be any chord; then will it be less than any diameter. For, from the point A draw the dia- meter AD, and draw also the radius CB. Then, in the triangle ACB, the sum of the sides A C and CB is greater than AB (B. I. A. 10. C). But A C + CB equals AD (Ax. 2) ; hence, AD is greater than AB. Therefore, etc; THEOEEM II. In the same circle or equal circles, equal angles at the centre intercept equal arcs on the circumference. In the equal circles ABC and DEF let the angle AOC equal DOF; then will the arc A C be equal to the arc DF. For, apply the circle ABC to the circle DEF so that the angle AOC shall coincide with the angle DOF. Then, since OC=OF and OA = 07), the point C will fall on F and the point A will fall on D, and the arc A C will coincide with the arc DF, since every point of each arc is equally distant from the centre of the circle. Therefore, etc. BOOK IV. 77 Cor. Conversely. — In the same circle or equal circles, equal arcs subtend equal angles at the centre. For, if we apply the equal arcs AC and DF, placing the point C on F, they will coincide, and the point A will fall on D; hence, the line OC will coincide with OF and OA with CD, and the angle AOC will be equal to DOF. THEOREM III. Any radius which is perpendicular to a chord bisects the chord and also the arc subtended by the chord. Let AB be the chord, and CD the radius perpendicular to it; then will AD'=DB and AE = EB.^ First. Draw the radii -CA and CB ; then the angle A CD equals DCB (B. I. Th. X. C. 1), and the triangles A CD and DCB are equal (B. I. Th. VI.) ; hence, the side AD equals DB. Second. Since the triangles A CD and DCB are equal, the angle ACE equals ECB ; hence, the arc AE equals the arc EB (Th. II. C). THEOREM IV. Through three points not in the same straight line a circumference may be made to pass. Let A, B, and C be any three points not in the same straight line; then may a circumference be described through them. Draw AB and BC, and at E and D, the middle points of AB and BC, draw perpen- diculars, and unite the points E and D. Now r since OED + ODE is less than two right angles, the perpendiculars will meet 7* 78 GEOMETRY. in some point, as (B. I. Th. IV. C. 3). Draw OA, OB, and OC; then OA = OB (B. I. Th. XIV.), and, for the same reason, OB = OC; hence, a circumference described from as a centre will pass through the three points A, B, and C. Cor. It may also be readily shown that but one circum- ference can be made to pass through three points. THEOREM V. If a straight line is perpendicular to a radius at its extremity, it will be tangent to the circle at that point. Let the straight line AB be perpendicular to the radius CD at D ; then will it be tangent to the circle at the point D. For, take any point of AB, as E, and draw the line CE. Now, CE is greater than CD (B. I. Th. XIV.); conse- quently, the point E will be without the circle, and hence the line AB touches the circumference in only one point : it is therefore tangent to it at the point D (D. 8). Therefore, etc. Cor. Conversely. — A tangent to the circle is perpendicular to the radius drawn to the 'point of contact. For any line, as CE, is greater than CF, or its equal CD ; hence, CD, being the shortest line from C to the tangent, is perpendicular to the tangent at D (B. I. Th. XIV.). Therefore, etc. THEOREM VI. Two parallel lines intercept equal arcs on the circumference. " There may be three cases : first, when both lines are secants ; second, when one is a secant and the other a tangent ; third, when both are tangents. BOOK IV. 79 First. Let AB and CD be two lines cutting the circle ; , then will the arcs MN and PQ be equal. For, draw the radius OR per- pendicular to the chord NQ; it will be perpendicular to MP (B. I. Th. III. C), and will bisect the arcs NRQ and MRP at the point JT(Th. III.) ; hence, NR equals RQ and MR equals RP; and, therefore, MR-NH=PR— QR, or MN equals PQ. Therefore, etc. Second. If one of the lines, as C'U, is a tangent. Then the radius OR, drawn to the point of contact, R, is perpen- dicular to the tangent CD 1 (Th. V.), and consequently to its parallel AB. Since OR is perpendicular to the chord MP, it bisects its arc MRP (Th. III.) ; hence, arc MR equals arc PR. Third. If both lines, as CD 1 and A'B', are tangents. Draw any secant, as AB, parallel to A'B' ; it will be parallel to C'U (B. I. Th. IV. C. 2). By the second case we have arc MK= arc PK, and arc MR= arc PR; adding, we have MR+ MK= PR+ PK, or arc RMK= arc RPK. Cor. 1. In the case of parallel tangents it is evident that each arc is a semi-circumference. Cor. 2. The straight line joining the points of contact of two parallel tangents is a diameter. Scholium. Regarding a tangent as a secant whose two points of intersection coincide, the demonstration of the first case of the theorem may be regarded as including the other two cases. 80 GEOMETRY. MEASUREMENT OF ANGLES. THEOEEM VII. In the same circle or in equal circles, two angles at the centre have the same ratio as their intercepted ares. Let ACB and DC'E be two angles at the centre" of equal circles, and AB and DE their intercepted arcs ; then will ACB: DC'E: : AB : DE. First. Suppose some com- mon unit is contained 5 times in the arc AB and 3 times in the arc DE; then arc AB : arc DE : : 5 : 3. Draw radii to the several points of division of the arcs ; the angles thus formed will he equal, since their arcs are equal (Th. II. C.) ; hence the angle ACB will consist of 5 equal parts and the angle DG'E of 3 such equal parts ; therefore angle A CB : angle DC'E : : 5 : 3. Comparing the two proportions, we have angle A CB : angle DC'E : : arc AB : arc DE. Second. Now this is true whatever the size of the unit of measure ; hence it is true when the unit of measure becomes indefinitely or infinitely small, as it must when the two arcs are incommensurable. Therefore, any two angles at the centre of the same or equal circles are to each other as their intercepted^ ares. BOOK IV. 81 THEOREM VIII. An angle having its vertex at the centre of a circle is measured by the are intercepted between its sides. Let A OB be an angle at the centre of the circle A CB, and AB its intercepted arc ; then will AB be the measure of the angle A OB. For, let B OD be the unit of measure of the angle A OB, and the arc BD be the unit of measure of the arc BA ; then, by Theorem VII., we have AOB-.DOB: : AB : DB, AOB = AB ° r ' DOB~ DB' Now, A OB divided by DOB equals the number of units in the angle A OB, and AB divided by DB equals the number of units in the arc AB; hence the number of units in the angle is equal to the number of units in the arc ; therefore the arc may be used as the measure of the angle. Scholium 1. This theorem is usually expressed thus: An angle at the centre is measured by its intercepted are. The statement is, however, rather conventional, " measured by " meaning " having the same numerical measure." Both angle and arc have the same numerical measure; hence the arc may be assumed as the measure of the angle. Scholium 2. It would seem more natural to measure an angle by a quantity of the same kind, and for this purpose the right angle would naturally be taken as the unit of measure. It has been found more convenient, however, to- use the arc of a circle as the measure of an angle, and for this purpose the circumference has been divided into degrees, minutes, and seconds, as before explained. 82 GEOMETRY. THEOREM IX. An angle having its vertex at the circwnference of a circle is measured, by half the arc intercepted between its sides. There may be three cases ; first, when the centre of the circle is on one of the sides of the angle ; second, when it is within the angle ; third, when it is without the angle. First. Let ABC be the angle, having its vertex at B, and be the centre of the circle; then will ABC be measured by one-half of A C. For, draw the radius AO ; then the exterior angle A OC is equal to the sum of the opposite interior angles ABO and OAB (B. I. Th. XIII. C. 5). But, the triangle A OB being isosceles, the angles A and B are equal ; and, consequently, the angle A OC is double the angle ABC. But AOC, being at the centre, is measured by the arc A C (Th. VIII.) ; hence, the angle ABC is measured by one-half of the arc AC. Second. Let ABC be the angle, and the eentre of the circle; then will ABC be measured by one-half of ADC. For, draw .the diameter BD ; then, from what we have just shown, the angle ABB is measured by one-half of AD. and the angle DBC by one-half of DC; hence, their sum, or the angle ABC, is measured by one-half of the sum of AD and DC, or one- half of ADC. Third. Let ABC be the angle, and the centre being without the angle; then will ABC be measured by one-half of -AG BOOK IV. 83 For, draw the diameter BD ; then, ABD is measured by one-half of AD, and GBD is measured by one-half of CD; hence, ABC, their difference, is measured by one-half of AD minus CD, or one-half of AC. Therefore, etc. Cor. 1. All the angles ABC, ADC, inscribed in a semicircle are right angles, being measured by one-half of the semi-circumference AEC (Th. IX.). Cor. 2. All the angles ABC, ADC, etc., inscribed in a segment greater than a semicircle are less than right angles, being measured by less than one-half of a semi-circumference. Any angle AEC inscribed in less than a semicircle is greater than a right angle, being measured by more than one-half of a semi-circumference. Cor. 3. All the angles inscribed in the same segment are equal, being measured by one-half of the same arc. Scholium. A right angle is measured by one-half a semi- circumference, or a quadrant. THEOREM X. The angle formed by a tangent and a chord is measured by half the are intercepted between its sides. Let AB be a tangent to the circle at C, and CD a chord meeting the tangent at C ; then will the angle A CD be meas^ ured by one-half the arc CED. 84 GEOMETEY. For, draw the diameter CE. The angle ACE is a right angle, and is measured by half the semi-circumference CFE (Th. IX. S.) ; the angle ECD is measured by half the arc ED (Th. IX.); hence, the angle ACD, which equals AGE + ECD, is measured by half the sum of the arcs CFE and ED, or by half the arc CFD. A Therefore, etc. THEOKEM XI. An angle formed by two chords which intersect is measured by half the sum of the intercepted arcs. Let AEC be an angle formed by the intersection of the chords AB and CD; then will it be measured by half the sum of A C and DB. For, draw DF parallel to AB; then the arc AF equals the arc DB (Th. VI.), and the angle FDC equals the angle AEC (B. I. Th. III.). Now, the angle FDC is measured by one- half the .arc FC (Th. VII.) ; hence, the angle AEC is measured by one-half of FC, or l(AC+AF), or i(AC+DB). Therefore, etc. THEOREM XII. The angle formed by two secants is measured by half the dif- ference of the intercepted arcs. Let the angle ABC he formed by the two secants AB and CB; then will it be measured by one-half the differ- ence of the arcs A C and ED. BOOK IV. 85 For, draw DF parallel to AB ; then the arc AF is equal to the arc ED, and the angle FDC equal to ABC. Now, the angle FDC is measured by one-half of the arc FC; heace, ABC is measured by one-half of FC; that is, by i(AC-AF) or i(AC-ED). THEOREM XIII. The angle formed by a secant and a tangent is measured by half the difference of the intercepted arcs. Let AB be a secant cutting the circle in E, and AC a tangent at the point D ; then will the angle BA C be measured by one-half of the difference of the arcs DB and DE. For, draw EF parallel to A C; then the angle FEB equals CAB, and the arc DE equals arc DF. Now, the angle FEB is measured by one-half of FB; hence CAB is measured by one-half of FB; butFB=DB-DF or DB - DE; therefore. CAB is measured by \(J)B — DE). THEOREM XIV. The angle formed by two tangents is measured by half the difference of the intercepted arcs. Let AB be a tangent at D, and AC a tangent at E; then will the angle BA C, be measured by- half the difference of the arcs DFE and DE. For, draw EF parallel to AB; then the angle FEC equals BAC, and the arc DE equals the arc DF. Now, the angle FEC is measured by half the 86 GEOMETRY. arc FE (Th. X.) ; hence BA C is measured by half the arc FE; but arc FE=DFE-DF, or DFE—DE; henceBAG is measured by i(DFE — DE). Therefore, etc. THE CIRCUMFERENCE AND AREA. THEOREM XV. The circumference of a circle may be circumscribed about a regular polygon, and it may also be inscribed within it. Let ABGD be a regular polygon ; then can the circum- ference of a circle be circumscribed about it. Through the three vertices A, B, and C, describe a circumference ; its centre will be in OK drawn perpendiculai to BG at its middle point K. The tri- A angle BOG being isoceles, the angles OBG and OCB are equal, which, being subtracted from the equal angles ABC and BCD, leave ABO and OCD equal; hence, the triangles OB A and OCB have two sides and an included angle respectively equal, and are equal (B. I. Th. VI.), and OD equals OA; hence, the circumference passing through A also passes through D; and in the same way it may be shown to pass through all the vertices. Second. Since the triangles A OB, BOG, etc. are all equal, their altitudes are equal ; hence, a circumference described from as a centre with the radius OK will touch all the chords at their: middle points, and, consequently, be in- scribed within the polygon. Therefore, etc. BOOK IV. 87 THEOREM XVI. The circumferences of circles are as their radii, and their areas are as the squares of their radii. Let C and be the centres of two circles whose radii are CA and OM; then ""'will their circumfer- ences be to each other as their radii, and their areas as the squares of their radii. Inscribe in the cir- cles regular polygons of the same number of sides. These polygons being similar figures, their perimeters are to each other as any two homologous, lines CA and OM, and their areas are as the squares of those lines (B. III. Th. XVIII. C); and this is true whatever -the number of sides; hence, it is true if the number of sides is infinite, and the , polygon becomes the circle. Hence, we have, circ. CA : circ. OM :: CA : OM; and, also, area CA : area OM : : HI* : OM\ Cor. 1. Since the radii of circles are to each other as- the diameters, we have the circumferences to each other as the diameters, and the areas as the squares of the dia- meters. Cor. 2. From this we see that the circumference of a circle is to its diameter as the circumference of another circle to its diameter ; hence, the ratio of the circumfer- ence to the diameter is a constant quantity. This con- stant ratio mathematicians represent by jt, the .Greek letter 88 GEOMETEY. p, called pi. Letting C represent the circumference and L Q the diameter we have jt = -= . Note. — This symbol ir is of great importance in mathematics : the pupil should be very careful to thoroughly understand its signification and use. THEOREM XVII. The circumference of a circle equals the diameter multi- plied by jr. Since the ratio of the circumference to the diameter is represented by jt, we have, Q — = tt; and, multiplying by D, we have, G=t:.D. Therefore, etc. Cor. Since the diameter is twice the radius, if we sub- stituted M for D, we will have, C=5rX 2iJ, or C=2nU. Hence, the circumference equals the radius multiplied by 2 jr. Remark. — The value of ir cannot be exactly expressed in numbers. The number generally used is 3.1416, which is sufficiently accurate for practical purposes. THEOREM XVIII. The area of a circle is equal to the circumference multiplied by one-half the radius. Let be the centre of a circle whose radius is OA, and circumference AB GD, etc.; then will its area be equal to circ. OAx? OA. BOOK IV. Inscribe in the circle a regular poly- gon ABOD, etc., and draw the radii OA, OB, etc., and the perpendicular OJE. The area of each triangle of the poly- gon is equal to its base multiplied by one-half its altitude, and since the alti- tudes are equal being radii of the inscribed circle, the area of the polygon is equal to the sum of the bases, or its peri- meter multiplied by one-half of OE. iN"ow, this is true whatever the number of sides ; hence, it is true when the number of sides'is infinite and the polygon becomes a circle. In this case the perimeter becomes the circumference, and the line E, the radius. Therefore, the area of a circle is equal to the circumference multiplied by one-half of the radius. Gor. The area of a circle is equal to the circumference multiplied by one-fourth of the diameter. THEOREM XIX. The area of a circle equals the square of the radius multi- plied by ic. Let G be the centre of a circle ; denote its radius CA by R, and its area by area GA; then from the previous theorem we have, area GA = circ. GAX h^> but, circ. CA = 2«R (Th. XVII. C.) ; hence, ' area GA = 2 it B X | -#, which, reduced, gives, area GA = n B 2 . Therefore, etc. 90 GEOMETEY. Cor. In a similar manner, we find that area CA = x \D\ or area CA = \-k U 1 . Scholium. The finding the exact length of the circum- ference of a circle is called the rectification of the circle. The finding of the area of a circle is called the quadra- ture of or squaring the circle. Both of these are celebrated problems, and can only be solved approximately, as may be shown by Calculus. It was stated in Theorem XVII. that the value of n is about 3.1416. This value is generally determined by find- ing a numerical expression for the area of a circle whose radius is unity, which area may be shown equal to the r?tio of the circumference to the diameter. The solution is given in the following proposition. THEOEEM XX. Problem. — To find the numerical value of jt, the ratio of the circumference to the diameter. The area of a circle equals tzT&; but when B = 1, the arsa of the circle equals it\ hence, we may find the value of 7t by finding the area of a circle whose radius is 1. As a circle is a polygon of an infinite number of sides, by con- structing successive similar inscribed and circumscribed polygons of double the number of sides, two may be found whose areas so nearly approach each other that either of them may be taken for the area of the circle. Let C be the centre of the circle, AB the side of an in- scribed, and EF of a circumscribed, polygon. Draw the chord AM, and the tangents AP and BQ; then AM will be the side of an inscribed, and PQ of a circumscribed poly- BOOK IV. 91 gon of double the number of sides. Draw CE, CP, CM and CF. Let P represent the area of the given circumscribed poly- gon ; p, the area of the given in- scribed polygon ; P', the area of a circumscribed polygon of dou- ble the number of sides ; and p', the area of an inscribed poly- gon of double the number of sides. Also, represent the tri- angles CEM, CAD, CPQ and CAM, which are respectively like parts of P, p, P and p', by T, t, T and f. 1. The triangle CAM is a mean proportional between CAD and CEM (B. III. Th. IX. C. 3), hence, T: H ::H :t; whence, P:p' ::p':p (B. II. Th. X.) ; therefore, p' = i/p X P. (1) 2. Because of a common altitude, CAM and CAD are to each other as CM to CD; and CEM to CPM as .EM" to PM; hence, t : t : : CM : CD, and, T:hT::EM:PM, by division, T— iTiiT:: EP-.PM, since EM— PM- EP. The triangles CAD and AEP are similar ; hence, AC : CD : : EP : AP, or, since AC= CM and XP = PJf, Cif: CD:: EP-.PM. Hence, from the first and third proportions, we have, (:t:: T—IT W; whence, p':p::2P—P P. (B. II. Th. X.) and p'+p:p::2P:F; (B. II. Th. VI.) whence. r 2pXP (2) p'+p 92 GEOMETRY. Now if' p and P are squares, the radius being 1, the area of P is 4; and the side of p is t/2 (B. III. Th. VI. C. 3) ; hence the area of p is 2 ; then, from (1), p' = i/^= 2.8284271, and, from (2), F = — ^— = 3.3137085 ; which are the areas of the inscribed and circumscribed octagons; and in the same manner we may find the areas of polygons of 16, 32, etc. sides. For 8192 sides, the area of the inscribed polygon is 3.1415923 -f , and of the circum- scribed polygon, 3.1415928 -f-, either of which may be taken for the area of the circle whose radius is 1 ; and, since we have shown this to be the value of w, we have n = 3.14159-t-. Scholium. The value of it is generally taken to be 3.1416. Note. — We invite special "attention to the method of treating the circum- ference and area of the circle, and also to the simple and concise method of ■ presenting the derivation of the value of ir, as given in the last proposition. PRACTICAL EXERCISES. 1. The radius of a circle is 6 inches ; what is its circumference ? 2. The diameter of a circle is 8 inches ; what is its area ? 3. The circumference of a circle is 50.2656 feet; required the radius. Ans. 8 feet. 4. The area of a circle is 490.875 square inches; required the dia- meter and circumference. Ans. Diameter, 25 ; circumference, 78.54: 5. The distance around a circular park is 180 rods ; required the area of the park. Ans. 16 A. 18.23 P. 6. What is the length of an arc of 75° on the circumference of a .circle whose radius is 5 feet ? Ans. 6.545 feet. 7. How many degrees in an arc 18 inches Ions', on a circumference Whose radius is 5 feet ? Ans. 17° IV 19". BOOK IV. 93 ' 8. A circle 20 feet in diameter is circumscribed by another- circle 30 feet in diameter; what is the area of the space included between them? 9. A has a circular garden whose diameter is 18 rods, and B has one whose area is 2 J times as great ; what is the diameter of B's garden ? Ans. 30 rods. 10. Find the side of a square inscribed in a circle whose diameter is 5 feet. Ans. 3.535 feet. 11. Within a circular park 160 rods in circumference is a circular lake-80 rods in circumference; required the width of the ring of land surrounding the lake. Ans. 12.732 rods. 12. Deborah has a circular garden and John a square one, and the distance around each is 120 rods ; which contains the most land, and how much? Ans. 245.95 square rods. 13. A man has a square garden and his wife a circular one, and each garden contains one acre; how much further around is one than the other? Ans. 5.756 rods. 14. The area of a circle is 344.16 ; if this circle be circumscribed by a square, required the area of the part between the circumference and the perimeter of the square. Ans. 85.84. 15. The area of a circle is 4 acres; required the side of the in- scribed square, and the area of the part of the circle between the cir- cumference and nerimeter of the square. Ans. 1 A. 1 R. 32 P. THEOREMS FOE ORIGINAL THOUGHT. 1. If two circumferences intersect, the distance between their cen- tres will be less than the sum of their radii and greater than the differ- ence. 2. If two circumferences intersect, the points of intersection will lie in a perpendicular to the line joining their centres, and at equal dis- tances from it. 3. In equal circles the greater arc has the greater chord, and, con- Tersely, the greater chord subtends the greater arc. 4. In equal circles, equal chords are equally distant from the centre, and the greater chord is nearer the centre. 5. If we inscribe a square in a circle, the radius is to the side of the inscribed square as 1 is to y/Z. 94 GEOMETEY. 6. If a regular hexagon be inscribed in a circle, each side will be equal to the radius of the circle. 7. The area of a triangle is equal to the perimeter multiplied by one- half the radius of the inscribed circle. 8. In any inscribed quadrilateral, the sum of the opposite angles is equal to two right angles. 9. When a quadrilateral circumscribes a circle, the sums of its oppo- site sides are equal. 10. When the radius of a circle is unity, its area and semi-circum- ference are numerically equal. PRACTICAL PROBLEMS IN GEOMETRY CAL CONSTRUCTION, INVOLVING THE PKINCIPLES OF BOOKS I., II., III., AND IV. The following problems are solved by the principles of tbe previous books. The solution of a few is given in full ; in others, the construction is given, and the reason for the solution indicated by referring to the theorem or theorems upon which it depends. The pupil will give the explanation in full. The object of these is to teach the pupil to draw accu- rately upon paper. They are of great use in drawing the notes of a survey, or in representing any geometrical figure upon paper. The pupils need two instruments, a rule and compasses; with these all the following problems may be readily solved PROBLEM I. To bisect a given straight line. Let AB be the given straight line. From A and B, as centres, with a radius greater than one-half of AB, describe arcs inter- x/ secting at E and F; draw the line EF; then will G be the middle point of AB. For, E and F are each equally distant from A and B; hence, EG bi- sects AB (B. I. Th. XIV. C. 3). t 95 96 GEOMETEY. PROBLEM II. From a given point without a straight line to draw a perpen- dicular to the line. Let AB be the given line, and G the given point. From G as the centre, with a radius suffi- ciently great, describe an arc cut- ting the line AB in the two points A and B; then from A and B as cen- tres, with a radius greater than one- half of AB, describe two arcs cut- ting each other in D, and draw GD; it will be the perpendicular required (B. I. Th. XIV. C. 3). 'V V A D -/* PROBLEM III. At a given point in a straight line to erect a perpendifiular-to that like. Let AB be the given line, and 6 the given point. Then, in the line AB take- the points A and B equally distant from G, and with A and B as centres, and a radius greater than one-half of AB, describe two arcs cut- ting each other at D ; draw DC; it will be the perpendicular required (B. I. Th. XIV. C. 3). PROBLEM IV. At a point on a given straight line to make an angle equal to a given angle. _ Let A be the given point, AB the given line, and EFG the given angle. From the point F as a centre, PEACTICAL PEOBLEMS. 97 with any radius FG, describe the arc EG. From A && & centre, with the same radius, describe the arc CB; then, with a radius equal to the chord EG, describe an arc from B as a centre, cutting the arc CB in D, and draw AD ; then will the angle DAB equal EFG (B. I. Th. IX.). PROBLEM V. To bisect a given arc, or a given angle. First. Let ADB be the given arc, and C its centre. Draw the chord AB, and from C draw CD per- pendicular to AB (P. II.); then will CD bisect AB(B. IY. Th. III.). Second. Let ACB be the given angle. Then, with C as a centre and any radius CA, describe the arc AB, and bisect this arc by the line CD, as in the previous case ; then will CD bisect ACB (B. IV. Th. III.). PROBLEM VI. Through a given point to draw a straight line parallel to a given straight line. Let A be the given point and CD the given line. From iasa centre, with a radius greater than the shortest dis- tance from. A to CD, describe an indefinite arc DE; from D as a (Jfi —^~ centre, with the same radius, de- \ __, " * \ scribe the arc AF; take DE equal -jgf 1 - — f B to AF, and draw AB; AB will be the parallel required. For, drawing AD, we have ADF = DAE (Prob. IV.) ; hence, AE and CD are parallel (B. I. Th. IV.). 98 GEOMETRY. PROBLEM VII. Two angles of a triangle being given, to find the third. Let M and N be the given angles. Draw the indefinite line AB; at any point, as C, construct the angle A CD equal to M, apd the angle DGE equal to N; then will EGB equaLthe third angle. PROBLEM VIII. Given two sides and the included angle of a triangle, to con- struct the triangle. Draw the indefinite line AD; take AB equal to one of the given sides; at A construct the ^ angle A equal to the given angle, and take A equal to the other given side; draw BG; then will ABC be the re- quired triangle (B. I. Th. VI.). PROBLEM IX. Given one side and two angles of a triangle, to construct the triangle. If the angles are not adjacent, find the third angle by P. VII. ; we then have two angles and the included side, and proceed thus : — Draw the indefinite line AD; take AB equal to the given side ; at A make the angle BA G equal to one of the an- gles; at B make the angle AB G equal the other angle; then produce A C and B C till they meet, and ABO will be the required triangle (B. I. Th. VII.). PRACTICAL PROBLEMS. 99 PROBLEM X. Given two adjacent sides of a parallelogram and the included angle, to construct the parallelogram. Draw the indefinite line AE, and upon it take AB equal to one of the sides. At A construct the angle BAB equal to the given angle, and take AD equal to the other given side. Draw DO parallel to AB, and B G parallel to AD; then will ABCDbe the parallelogram required (B. I. Th. XV. C. 3). PROBLEM XL To find the centre of a given circumference or arc. Take any three points, A, B, and G, on- the circumference or arc, and unite them by the lines AB and BG. Bisect these chords by the perpendiculars DO and BIO j then will their intersection be the centre of the circle (B. IV. Th. IV.). PROBLEM XII. Through a given point to draw a tangent to a given circle. First. Suppose the given point P to be in the circum- ference. Find G, the centre of the circle (P. XI.); draw the radius GP; and then through P draw the perpendicular DE; DE will be the tangent re- quired (B. IV. Th. V). Second. Suppose the given point P 100 GEOMETRY. to be without the circle. Join P and the centre of the circle ; bisect PG in D ; with Das a centre, and a ra- dius DO, describe the circumference intersecting the given circumference in A and B; draw PA or PB; then each of those will be the tangent required. For, since GAP is a semicircle, the angle GAP is a right angle (B. IV. Th. IX. C. 1); hence, AP is a tangent (B. IV. Th. V). PROBLEM XIII. To divide a given line into any number of equal parts. Let AB be the given line, and suppose we wish to divide it into any number, say 5 equal parts. Through A draw the indefinite line AE, making any angle with AB. Take AC of any convenient length, and apply it 5 times to AE; join B with the last point of the division; and through the other points of division draw lines parallel to EB; then will AB be divided into 5 equal parts. For, since DG and BE are parallel, we have (B. III. Th. IX.), AG : AE : : AD : AB. But AC is one-fifth part of AE; hence, AD is one-fifth part of AB. PROBLEM XIV. To divide a given line into parts proportional to given lines. Let AB be the given line, to be divided into parts pro- PRACTICAL PROBLEMS portional to the given lines P, Q, and E. A G, making any angle with AB. On AG lay off AG equal P, CE equal Q, EG equal JR; draw BG, and from the points G and E draw CD and EF .parallel to GB; then will AD; DF, and FB be proportional to AG, GE, and EG (B. III. Th. IX.). PROBLEM XV. To construct a mean proportional to two given lines. Let Pand Q be the two given lines. Draw an indefinite line, and on it lay off -ID equal to P, and DB equal to Q ; on AB as a diameter describe a semicircle, and draw D per- pendicular to AB; then, in the triangle AOB, will DO be a mean proportional to AD and D.B (B. III. Th. XIV.). PROBLEM XVI. To construct a square equal to a given triangle. Let ABC be the given triangle, AB its base, and OD its altitude. Find a mean proportional between CD and one-half of AB (Prob. XV.). Let FG be that mean proportional, and on it, as a side, construct the square FGHI; this will be the square required. For, by the construction, we have FG 2 = ^ AB X' GD, which equals the area of ABG. 9* 102 GEOMETKY. PROBLEM XVII. To inscribe a regular hexagon in a circle. Suppose the problem to be solved, and that ABCDEF is a regular hexagon; draw the radii " OB and OC. Now, the arc BC is one- sixth of a circumference, or 60° ; hence,' the angle BOG is 60°, and the other angles OBCand BOO equal 180° minus 60°, or 120°, and, OB being equal to OC, the angles OBC and BCO are equal; hence, each is equal to one-half of 120°, or 60°. Con- sequently, the triangle OBC is equiangular, and therefore equilateral; hence, the side BC is equal to the radius OB. Therefore, to inscribe a regular hexagon in a circle, w» apply the radius six times as a chord to the circumference. PROBLEMS FOE ORIGINAL THOUGHT. 1. Given the three sides of a triangle, to construct the triangle. <2. v Given two sides of a triangle, and the angle opposite one of them, to construct the triangle. 3. To inscribe a circle in a given triangle. 4. To inscribe a circle in a square, and a square in a circle. 5. To find the side of a square which shall be equal to the sum of two given squares. 6. To find the side of a square which shall be equal to the difference between two given squares. 7. To construct a rectangle equal in area to a given triangle. 8. To find a fourth, proportional to three given lines. 9. On a given line to construct a rectangle which shall be equal to a given rectangle. 10. To construct a square that shall be equal in area to a given paral- lelogram. BOOK V. PLANES AND THEIR ANGLES. DEFINITIONS. 1. APlane is a surface such that a straight line con. necting any two of its points will lie entirely in the surface. 2. A straight line is perpendicular to a plane when it is perpendicular to every line of the plane passing through its foot. The foot is the point where the line meets the plane. ileciprocally, the plane is also perpendicular to the line. 3. A straight line is parallel to a plane when it can- not meet the plane, however far both be produced. Eeciprocally, the plane is also parallel to the line. 4. Two planes are parallel when they cannot meet, however far both be produced. 5. "When two planes meet, they form a line, which is called their line of intersection. 6. ADiEDRALANGLEis the divergence of two planes. The line in which the planes intersect is called the edge of the angle; the planes are called the faces of the angle. A diedral angle is measured by the an- gle formed by two lines, one in each plane and perpendicular to the edge at the same point. Thus, the diedral angle in the margin is mea- sured by the angle ACB. 103 104 GEOMETEY. 7.. A Polyedral Angle is the divergence of three or more planes proceeding from a common point. The common point is called the vertex of the angle; the planes are its faces; the intersection of the planes, its edges., 8. A Triedral Angle is a polyedral angle of three faces. 9. Two planes are Perpendicular to each other when their diedral angle is a right angle. Anaiysis. — This Book treats of planes, the lines and angles formed by their intersection. It is not so valuable in itself as the other Books of Geometry, and much less interesting. Its object is to prepare for the Book which immediately follows it. THEOREM I. Through three points not in the same straight line, one plane can be passed, and but one. Let A, B, and C be the three points ; then can one plane be passed through them. For, join two of the points, as A and C, by the line AC. Pass a plane through AC, and turn it around AC until it con- tains the point B; it will then pass through the three points A, C, and B. If now the plane be turned about A C, it will no longer contain the point Bj hence, only this one plane can be passed through the three points. Therefore, etc. Cor. 1. Since only one plane can be passed through three points, three points are said to determine the posi- tion of a plane. Cor. 2. Two lines which are parallel or which intersect de- termine the position of a plane. BOOK V. 10 5 THEOREM II. If two planes cut one another, their common section is a straight line. Let the, two planes AB and CD cut one another in the points E and F ; then will their common section be a straight line. For, draw the line EF. uniting the two common points E and F of the planes. Now, this line, having two points in the plane AB, will lie wholly in the plane AB (B. I. Def.), and, having two points in the plane CD, it will lie wholly in the plane CD; hence, the line EF is common to both planes, and must therefore be in their common intersection. Therefore, etc. THEOREM III. If from a point without a plane lines be drawn to the plane, 1. The perpendicular is the shortest distance from the point to the plane ; 2. Oblique lines which meet the plane at equal distances from the foot of the perpendicular are equal ; 3. Of two oblique lines which meet the plane at unequal dis- tances from the foot of the perpendicular, the one which meets it at the greater distance is the longer. Let A be a point without the plane MN; let AB be a per- pendicular to the plane, and let A C, AD, and AE be oblique lines. First. AB will be shorter than any oblique line A C. For, through B draw the line BC; then in the triangle ABC, AB is less than A C (B. I. Th. XIV.). Seeond. Let A C and AD meet the plane at equal distances 106 GEOMETRY. from the point B; then A C will be equal to AD. For, draw BC and BB; then the right-angled triangles ABC and ABD will have BC equal to BD, and the side AB common ; hence, the tri- angles are equal, and AG equals AD. Third. Let AC and AE meet the plane so that the distance BE is greater than BC; then AE will be greater than AC. For, take BF equal to BC and draw AF; then AE>AF (B. I. Th. XIV) ; but AF=AC; hence, AE>AC. Cor. 1. Equal oblique lines drawn from a point to a plane meet the plane at equal distances from the foot of the per- pendicular; and of two unequal oblique lines, the greater meets the plane at the greater distance from the foot of the perpendicular. Cor. 2. The equal oblique lines meet the plane in the cir- cumference of a circle whose centre is B ; hence, to draw a perpendicular from a point A to a given plane MN, find any three points, C, D, and F, of the plane equally distant from A, then find the centre of the circumference passing through these points ; then AP will be the perpendicular required. THEOEEM IV. If a straight line is perpendicular to two straight lines of a plane at the point of their intersection, it is perpendicular to the plane of those lines. Let AP be perpendicular to PB and PC at the point P; theti will it be perpendicular to MN, the plane of those lines. For, let PD be any other straight line of the plane MN BOOK V. 107 drawn through P. Draw BC, cutting PB, PD, and PC in B, D, and C; produce AP making PA' = AP; and draw AB, AD, AG, A'B, A'D and A'G. Then, since BP and CP are perpendicular to A A' at its middle point, AB equals A'B, and A C equals A'C, and the tri- angles ABC and A'BC are equal (B. I. Th. IX.), and also AD equals A'D ; whence PD is perpendicular to AA' (B. I. Th. XIV. C. 3). Hence, AP is perpendicular to any line passing through its foot ; it is, therefore, perpendicular to the plane MN. Cor. Only one perpendicular can be erected to a plane from a point of the plane. THEOEEM V. If from the foot of a perpendicular to a plane a line is drawn at right angles to any line of the plane, and the point of intersection is joined with any point of the 'perpendicular, the last line will be perpendicular to the line of the plane. Let AP be a perpendicular to the plane MN, P its foot, BC the given line, and Aja.nj point of AP; draw PD perpendicular to BC, and join the points A and D; then will AD be perpendicular to BC. For, lay off BD equal to DC, and draw PB, PC, AB, and A C. Since PD M is perpendicular to BC, and DB equals DC, PB equals PC (B. I. Th. XIV.) ; hence, in the triangles APB and APC, AB equals A C. Therefore the line AD, having two points, A and D, equally distant from B and C, is perpendicular to BC (B. I. Th. XIV. C. 3). 108 GEOMETRY. Cor. The line BC is perpendicular to the plane of the tri- angle APD, because it is perpendicular to AD and PD at the point D (Th. IV.). THEOREM VI. Ij one of two parallels is perpendicular to a plane, the other is also perpendicular to the plane. Let AB and CD be two parallel lines, and let AB be per- pendicular to the plane MN; then will CD also be perpendicular to MN. For, pass a plane through the parallels cutting MN in BD ; draw AD, and in the plane MN draw EF perpendicular to BD at the point D. Then, EF is perpendicular to the plane A BD C (Th. V. C.) ; henee, the angle EDC is a right angle ; but CDB is a right angle, since CD is parallel to AB (B. I. Th. III. C.) ; hence, CD is perpendicular to the two lines BD and EF at their point of intersection ; it is, therefore, perpendicular to the plane MN (Th. IV.). Therefore, etc. Cor. 1. Conversely. ■-- Two lines which are perpendicular to the same plane are parallel. For, suppose the two lines AB and CD to be perpendicular to the plane MN; then, if they are not parallel, draw from the point D a line which is parallel to BA ; this line will be perpendicular to MN (Th. VI.) ; we shall then have two perpendiculars to the plane MN from the same point, which is impossible (Th. IV. C.) ; therefore, AB and CD are parallel. Cor. 2. Two lines parallel to a third line are parallel to each Hher. Let the two lines A and B be parallel to a third line ; pass a plane perpendicular to C,~it will be perpendicular BOOK V. 109 to both A and B (Th. VI.) ; hence, A and B, being perpen- dicular to the same plane, are parallel (Th. VI. C. 1). THEOKEM VII.- If two planes are perpendicular to the same straight line, they are parallel. Let the two planes MN and PQ be- perpendicular to the straight line ABj then will they be parallel. For, if they are not parallel, they will meet in some point 0. Prom draw the lines OA and OB; then, since OA lies in the plane MN, it will be perpendicular to AB at A (D. 2) ; and since OB lies in the plane PQ, it will be perpendicular to AB at B. Hence, we have two perpendiculars drawn from the same point to the same straight line, which -is impossible (B. I. Th. XIV. C. 1); consequently, the planes cannot meet, and are, therefore, parallel. THEOREM VIII. If a plane meet two parallel planes, the lines of intersection are parallel. Let the plane AG intersect the two parallel planes MN and PQ; then will AB and CD be parallel. For, if the lines AB and CD are not parallel, since they lie in the same plane, they will meet if sufficiently produced, and, consequently, the planes MN and PQ will meet; but the planes cannot meet, since they are parallel ; hence, the lines AB and CD cannot meet ; they are, there- fore, parallel. 110 GEOMETRY. ,/■ t-r D I' Kf Gor. Parallel lines included between parallel planes are equal. For, the opposite sides of the figure AG being parallel, it is a parallelogram, and hence AD equals BG. THEOREM IX. If a straight line is perpendicular to one of two parallel planes, it is perpendicular to the other also. Let MN and PQ be two parallel planes, and let the line AB be perpendicular to PQ; then will it also be perpendicular to the plane MN. For, pass any plane through AB; the intersections A C and BD will be paral- lel (Th. VIII.) ; since AB is perpendicular to PQ, it will be perpendicular to BD (D. 2), and since BD and A C are parallel, & a it will be perpendicular to A G (B. I. Th. III. C.) ; hence, BA, being perpendicular to any line of the plane MN passing through its foot, is perpendicular to the plane MN. Therefore, etc. THEOREM X. If two angles not in the same plane have their sides parallel and lying in the same direction, the angles will be, equal a,nd ' their planes parallel. Let BAG and DEF be two angles not in the same plane, having their sides respectively parallel e and lying in the same direction ; then will these angles be equal and their planes parallel. Take ED equal to AB, and EF equal to AG, and draw BG, DF, AE, BD, and GF. First. The angles BA G and DEF will be equal. /< D 1\ ■1 p N 1- B .1 BOOK V. HI For, sincere and EF are equal and parallel, the figure AGFE is a parallelogram (B. I. Th. XVII.), and AE and GF are equal and parallel. Since AB and ED are equal and parallel, ABBE is a parallelogram, and AE and BD are equal and parallel ; hence, BD and OF are equal and paral- lel (Th. VI. C. 2), and, consequently, D-Fis equal and parallel to B C. Hence, the triangles AB C and EDF have their cor- responding sides equal; they are, therefore, equal, and the angle DEF equals the angle BA G. Second. The planes are parallel. For, three lines which intersect determine the position - of a plane ; and since the three sides of the triangles aro respectively parallel, their planes must be parallel. Cor. If three straight lines not in the same plane are equal and parallel, the triangles formed by joining the extremities of these lines will be equal, and their planes parallel. This is readily proved ; let the pupil show it. . THEOREM XI. If two straight lines are cut by three parallel planes, they will be divided proportionally. Let the lines AB and GD be cut by the parallel planes MN, PQ, and BS, in the points A, E, ' s B, and G, G, D; then will [~^°~] AE : EB : : GG : GD. I f\ 1 / s l\ T Q For, draw the line AD, meeting the /~j V I 7 plane PQ in F; draw also A G, EF, FG, I s j~iTT I " and BD. Now, since the planes MN p — r \ i and PQ are parallel, EF is parallel to f~j Vj 7 ( BD (Th. VIII.) ; and since PQ and RS I L— _ ___J / are parallel, AG is parallel to FG. L / Hence (B. III. Th. IX.), we have, 112 GEOMETEY. AF:EB::AF: FD; and also, AF-.FD:: GG: GD. Hence, from the principles of proportion, we have, AE:EB::CG: GD. Therefore, etc. THEOREM XII. Hither angle of the three plane angles which form a triedral angle, is less than the sum of the other two. Let the triedral angle whose vertex is S be formed by the three plane angles ASG, ASB, and GSB; then will any one of these be less than the sum of the other two. If the angle considered is less than either of the other two, it is evidently less than their sum. Suppose, how- ever, the angle greater than either of the other two, and let ASB be that an- gle. In the plane ASB make the angle BSD equal to BSG, draw the line AB at pleasure, make SO equal to SD, and draw AG and BG. In the two triangles BSG and BSD, BS is common, CS equals DS, and the angle BSG equals BSD by construction ; hence, the triangles are equal, and BD equals BG. Now (B. I. A. 10, C), AD + DBp 126 GEOMETRY. edges which meet at the same vertex. Let the pupil show it ; that SB 1 = BC* + DC* + DR\ THEOREM VIII. The volume of a rectangular parallelopipedon is equal to the product of its base and altitude. lietABCB — H be a rectangular parallelopipedon; then will its volume be equal to its base ABGD multiplied by its altitude AB. Suppose AK to be a common unit of measure of the three sides AB, AD, and AB, and suppose it to be contained 4 times in AB, 3 times in AD, and 5 times in AB; then divide AB into 4 equal parts, AD into 3, and AB into 5 equal parts, and pass planes through the points of division parallel to the faces of the parallelopipedon. The parallelopipedon will thus be divided into equal cubes, oqual since their sides are equal and their angles are equal, all being right angles. Now, the number of these little cubes upon the base is equal to the number of surface units in the base, and the whole number of cubes in the parallelopipedon is equal to the number upon the base multiplied by the number of layers, and the number of layers is the same as the number of units in the- altitude ; hence, the number of cubic units in the parallelopipedon is equal to the base multiplied by the altitude. Now, this is evidently true whatever be the size of the linear unit; hence, it is true when the linear unit is exceedingly small, and, consequently, when it is infinitely small, as it -must be when the three sides are / / *£ft 1/ 1 / / / ti rr / rrtr / BOOK VI. 127 incommensurable. Therefore, the volume of a rectangular parallelopipedon is equal to the' product of its base and altitude. Cor. 1. It is evident that the number of cubic units upon the base is equal to the number of rows multiplied by the number in each row ; that is, the length of the base mul- tiplied by its breadth; hence, the volume of a rectangular parallelopipedon equals the product of its length, breadth, and altitude, or the product of its three dimensions. Cor. 2. Any two rectangular parallelopipedons are to each other as the products of their bases and altitudes, or as the products of their three dimensions. Cor. 3. "When their bases are equal, they are to eacb other as their altitudes; when their altitudes are equal, they are to each other as their bases. THEOEEM IX. The volume of any parallelopipedon is equal to the product of its base and altitude. Let ABCD—E be any parallelopipedon whose base is ABCD and altitude H; then will its volume be equal to the base ABCD multiplied by the altitude H. For, the parallelopipedon ABCD—E is equivalent to a rectangular parallelo- pipedon having the same altitude and an equivalent base (Th. V.) ; but the volume of such a rectangular parallelo- pipedon is equal to the product of its base and altitude (Th. VIII.) ; hence, the volume of the parallelopipedon ABCD — E is equal to the product of its base and altitude. Therefore, etc.- 128 GEOMETRY. THEOEEM X. The volume of any prism is equal to the product of its base and altitude. This prism is 1st. ~Let ABC — E be a triangular prism, half the parallel opiped on constructed on its edges AB, BC, and BF (Th. VI.). The volume of this parallelo- pipedon is equal to its base ABQD mul- tiplied by its altitude (Th. IX.) ; hence, the volume of the triangular prism ABC— E is equal to its base ABC, the half of ABCD, multiplied byits altitude. 2d. Let ABCDE — F be any prism. Divide it into tri- angular prisms by passing planes through any lateral edge BG; these prisms will have a common altitude, the altitude of the prism. The volume of any triangular prism,' ABE — F, is equal to the product of its base and altitude, as. just shown ; hence, the volume of the prism ABCDE—F, which is the sum of these triangular prisms, is equal to its base, which is the sum of the bases of the triangular prisms, multiplied by its altitude. Therefore, etc. Cor. 1. Prisms having equivalent bases and equal altitudes are equivalent. Cor. 2. Any two prisms are to each other as the products of their bases and altitudes. Cor. 3. Prisms having equal altitudes are to each other as their bases. Cor. 4. Prisms having equal bases are to each other as their, altitudes. BOOK VI. 129 THEOEEM XI. Similar triangular prisms are to each other as the cubes of their homologous edges. Let ABG—E and GBH—L be two similar triangular prisms ; then will they be to each other as the cube of any two homologous edges AB and GB. For, since the two prisms are similar, the faces con- taining the triedral angles B and B are respectively similar ; therefore, the prism GBH—D being applied to th p prism ABG—E will take the position GBJE—P. From D draw DM perpendicular to the base, and from K draw KN perpendicular to the base ; then the two triangles JDMB and KNB must be similar, since they are mutually equiangular. Now, since the bases are similar, we have (B. III. Th. XVL), base ABC: base GBR: : AB 1 : GB 2 ; and, since the triangles DMB and KNB are similar, and also the parallelograms AD and GK, we' have, DM: KN: : DB : KB : : AB : GB. Multiplying together the corresponding terms of the first and last couplets of these two proportions, we have, " base ABC X DM: base GBSX KN: -.AB 3 : GB 3 . But baseABGX DM is the volume of the prism ABG—E, and base GBB X KN is the volume of the prism GBH—L; hence, the prisms are to each other as AB 3 to G£ 3 . Therefore, etc. 130 GEOMETRY. Cor. 1. Any two similar prisms are to each other as the cubes of their homologous edges. For, since the prisms are similar, their bases are similar, and may, therefore, be divided into the same number of similar triangles, similarly situated (B. III. Th. XVII.); hence, each prism may be divided into the same number of similar triangular prisms. But these triangular prisma are to each other as the cubes of their homologous edges ; hence, the polygonal prisms 'which are respectively the sum of these triangular prisms must be to each other as the cubes of their homologous edges. Cor. 2. Similar prisms are to each other as the cubes of their altitudes, or as the cubes of any other homologous lines. THE PYRAMID. THEOEEM XII. The convex surface of a right pyramid is equal to the perime- ter of the base multiplied by one-half of the slant height. Let ABCDE — S be a right pyramid, and SS the slant height; then will the convex surface be equal to the perimeter AB -\-BC-\- CD -\- DE + EA multiplied by £ of SIT. Draw SO perpendicular to the base; then, from the definition of a right pyra- mid. O is the centre of the base ; conse- quently, the distances AO,BO, CO, etc. are all equal, and tharefore the edges SA, SB, SC, etc., are all equal (B. V. Th. III.) ; and, since ,the sides AB, BC, etc., are all equal, the triangles SAB, SBC, etc. are all equal, and BOOK VI. 131' their altitudes, which is the slant height of the pyramid, are equal. Now, the area of each triangle is equal to its base multi- plied by one-half of its altitude ; hence, the sum of the areas of these triangles, which is the convex surface of the pyramid, equals the sum of their bases into one-half of the slant height SH; that is, the convex surface of the pyramid equals (AB + BC+CD + DE + EA)Xh ss - Therefore, etc. THEOREM XIII. If a pyramid be cut by a plane parallel to the base; 1. The edges and altitude will be divided proportionally. - 2. The section will be a polygon similar to the base. Let the pyramid S— ABODE be cut by a plane GHIKL parallel to the base ; then will the edges SA, SB, SO, etc., with the altitude SO, be divided proportionally, and the section GHIKL will be similar to the base. First. Since the planes ABODE and GHIKL are parallel, the intersections AB and GH are parallel (B.V. Th.V-IIL); for the same reason, BO is parallel to HI, and BO to IIP. Hence, we have (B. III. Th.IX. C. 1), , SA:SG::SB:SH; and also, SB :SS: : SO: SI; and also, SB : SH : : SO : SP. Hence, the edges and altitude are divided proportion- ally. 132 GEOMETKY. Second. Since GH is parallel to AB, and HI to JBC, the angle GHI is equal to ABC (B. V. Th. X.) ; and, for the same reason, each angle of the polygon GHIKL is equal to the corresponding angle of the hase ; hence, the two polygons are mutually equiangular. Again, since GH is parallel to AB, we have, GH:AB::SH:SB; and, since HI is parallel to BC, we have, HI:BC::SH:SB. Hence, from equal ratios, we have, GH:AB::HI:BG. In the same manner, it may he shown that all the sides of the two polygons are proj)ortional; hence, the section GHIKL is similar to the base ABGDE (B. III. D. 6). THEOREM XIV. If two pyramids have the 'same altitude, and their bases in the same plane, the sections made by a plane parallel to their bases are to each other as their bases. Let S— ABCBE and S—MNO be two pyramids, having the same altitude, and their bases in the same plane; and let GHIKL and PQB, he sections made by a plane parallel to their bases; then will these sections be to each other as the bases. For, the polygons ABODE and GHIKL, being similar, are to each other as the squares of their sides AB and GH (B. III. Th. XVIII.) ; but BOOK VI. 133 AB:GH::SA:SG. Hence, ABODE : GHIKL : : #Z 2 : SG\ For a similar reason, MNO : PQB : : SM> : SP 1 - But (B. V. Th. XI.) we have, 8A:SG::SM:SP: Hence, AB ODE : GHIKL : : MNO : PQB. Therefore, etc. Cor. 1. If the bases are equal, any two sections parallel to the bases at equal distances from the vertices are equal. Cor. 2. Any two sections parallel to the base are propor- tional to the squares of their distances from the vertex. THEOEEM XV. Two triangular pyramids having equivalent bases and equal altitudes are equal in volume. Let S — ABC and S'—A'B'C be two triangular pyramids having equivalent' bases ABC and A'B'C and equal altitudes A T; then will these pyramids be equal in volume. For, place the bases of the pyramids in the same plane, divide the altitude, A T, into any number of equal parts, and through the points of division pass planes parallel to the plane of their bases, forming the sections DEF, D'E'F', etc., 12 134 GEOMETRY. and construct prisms in the two pyramids with these sections as upper bases. Now, the corresponding sections DEF, D'E'F', etc., are equivalent (Th. XIV.) ; hence, the corresponding prisms, having equivalent bases and equal altitudes, are equivalent (Th. X. C. 1). Now, this is true whatever the equal number of inscribed prisms ; hence, it is true when the number in each prism becomes indefinitely or infinitely great, in which case they will coincide respectively with the two pyramids ; therefore, the pyramids are equal in volume. Therefore, etc. THEOREM XVI. A triangular prism may be divided into three equal triangular pyramids. Let ABC — F be a triangular prism; then may it be divided into three equal triangular pyra- mids. Pass a plane through the edge AC and the point i?, cutting off the pyramid ABO — E; pass an- other plane through HE and the b point 0, cutting off the pyramid DEF—G; there will re« main a pyramid whose base may be regarded as ACD, having its vertex at E. Now, the two pyramids ABC — E and DEF — are equal in volume, since they have equal bases and equal altitudes (Th. XV.). Regarding the pyra- mid DEF — as having the base DCF and vertex &% E, it is equal in volume to the pyramid A CD — E, since their bases are equal, being halves of the parallelogram A CFD, and their altitudes are equal, since their bases are in the same plane and vertices at the same point. Hence, the BOOK VI. 135 three pyramids into which the prism is divided are all equal in volume. Therefore, etc. Cor. 1. A triangular pyramid is one'-third of a prism having an equal base and an equal altitude. Cor. 2. The volume of a triangular pyramid is one-third of the product of its base and altitude. ' THEOREM XVII. The volume of a pyramid is equal to one-third of the product of its base and altitude. Let & — ABCDE be a pyramid, and SO the altitude ; then will its volume be equal to ABCDE X ISO. Draw the diagonals A C and AD, and pass the planes SA C and SAD through these diagonals and the vertex S; the pyramid will then be divided into tri- angular pyramids, whose altitiides are equal, being the altitude of the pyra- mid. Now, the volume of each of these triangular pyramids is equal to its base by one-third of the altitude (Th. XVI. C. 2) ; hence, the volume of the pyramid S — ABCDE, which is the sum of these triangular pyra^ mids, is equal to the sum of their bases into one-third of the altitude ; that is, base ABCDE X i SO. Therefore, etc. Cor. 1. The volume of a pyramid is one-third of the volume of a prism having an equal base and an equal alti- tude. Cor. 2. Pyramids are to each other^ as the products of their bases and altitudes. Cor. 3. Pyramids having equal bases are to each other 136 GEOMETEY. as their altitudes ; pyramids having equal altitudes are to each other as their bases. Scholium. The volume of any polyedron may be found by dividing it into triangular pyramids, by passing planes through its vertices. THEOEEM XVIII. Similar pyramids are to each other as the cubes of their homo' logons edges. Let S— ABODE and S— FGHIK be two similar pyra- mids ; then will they be to each other as the cubes of any two homologous sides AB and FG. For, since the pyramids are similar, they may be so placed that their ho- mologous angles at the vertex will coincide. Then, since the faces SAB and SFG are similar, AB is parallel to FG; and since SBC and SGH are A j, similar, BO is parallel to GH; hence, the planes of the bases are parallel (B. Y. Th. X.). Draw SO perpendicular to the base AB ODE; it will also be perpendicular to the base FGHIK a,t some point, P; then (Th. XIII.), SO :SP:: SB. :SG::AB: FG; and, consequently, ISO : \ SP : : AB : FG. But, the bases of the pyramids being similar, we have (B. III. Th. XVIII.), base ABODE : base FGHIK: : AB* : FG\ Multiplying these two proportions, term by term, we have, base ABODE X\SO: base FGHIK X%SP: -.IB 3 : FG 3 . BOOK VI. 137. But, base ABODE X \ SO is "equal to the volume of the pyramid 8— ABODE, and base FGHIK X i SPin equal to the volume of the pyramid S— FGHIK ; hence, the two pyramids are to each other as the cubes of the homologous edges AB and FG-. Therefore, etc. Oor. Similar pyramids are to each other as the cubes of their altitudes, or as the cubes of any two homologous lines. FRUSTUM OP A PYRAMID. THEOREM XIX. The convex surface of a frustum of a right pyramid is equal to one-half of the sum of the perimeters of the upper and lower bases, multiplied by the slant height. Let ABODE— K be the frustum of a right pyramid, and NM its slant height ; then will its convex surface be equal to one-half of the sum of the perimeters of its two bases) multiplied by NM. The faces forming the convex surface are equal trapezoids; for the faces of the n a pyramid of which this frustum is a part are equal, and the faces of the pyramid cut off are equal; hence, the figures which remain are equal, and their upper and lower bases being parallel, they are equal trapezoids, and have a com- mon altitude NM, the slant height of the frustum. , Now, the area of each trapezoid, as ABGF, is equal to | (AB + FG) X NM (B. III. Th. IV.) ; hence, the area of the convex surface, which is the sum of all the trapezoids, is equal to one-half the sum of the perimeters of the upper and lower bases multiplied by the slant height. There- fore, etc. 12* 138 GEOMETEY. THEOREM XX. The volume of a frustum of a triangular pyramid is equal to the sum of the volumes of three pyramids, whose common altitude is the altitude of the frustum, and whose bases are the lower base of the frustum, the upper base of the frustum, and a mean proportional between the two bases. Let ABC — F be the frustum of a triangular pyramid. Through the points A, E, C, pass a plane cutting off the pyramid E — ABC. This pyramid has the altitude of the frustum, and for its base the lower base of the frustum. Through the points D, E, C, pass a plane cutting off the pyramid C—DEF This pyramid has the altitude of the frus- tum, and for its base the upper base of the frustum. The remaining part of the frustum is a pyramid whose base is ACD, with its vertex at E. Now, draw EG parallel to DA; draw also GD; then the pyramid E — A CD is equal to the pyramid G — A CD, since they have the same base and equal altitudes. But the pyramid G — ACD may be regarded as having A GC for its base, and its vertex at D; it will then have the altitude of the frus- tum. We will now show that its base AGO is a mean pro- portional between the two bases of the frustum. Draw GH parallel to BC ; then the triangles A GH and DEF, being similar to ABC, are similar to each other, and, hence, equiangular; and since AG equals DE, the triangle AGS equals DEF (B. I. Th. VII.). Now, AGC is a mean proportional between A GH and AB C (B. III. Th. IX. C. 3) ; hence, the base of the third pyramid is a mean propor- tional between the upper and lower bases. Therefore, etc. BOOK VI. 139 Cor. This proposition is true for the frustum of any pyra- mid. For, since any pyramid is equal to a triangular pyra> mid having an equal base and equal altitude, by cutting , the pyramids with a plane parallel to the base, and re- moving the upper part, it may be shown that the frustum of any pyramid is equal to the frustum of a triangular pyramid having equal bases and the same altitude; hence, if the proposition is true for triangular frustums, it is true for all frustums. REGULAR POLYEDRONS. A Regulab Polyedkon is one whose faces are all equal and regular polygons. There can be five, and only five, regular polyedrons, namely : 1. The Teteaedbon, or regular pyramid, a polyedron bounded by four equal equilateral triangles. 2. The Hexaedeon, or cube, a polyedron bounded by six equal squares. 3. The Octaedeon, a polyedron bounded by eight equal equilateral triangles.^ 4. The DoDECAEDEOif, a polyedron bounded by twelve equal regular pentagons. 5. The Icosaedeon, a polyedron bounded by twenty equal equilateral triangles. 1st. In the tetraedron the polyedral angle is formed of three equilateral triangles ; in the octaedron, of four such triangles ; in the icosaedron, of five triangles. The combina- tion of six such angles (each angle being f of a right angle) gives four right angles, or a plane, and hence no polyedral 140 GEOMETRY. angle ; and the combination of more than six will not form a convex angle; hence only three regular polyedrons can be formed of triangles. 2d. In the hexaedron the polyedral angle is formed of three squares. The combination of four squares gives a plane, and a greater number would not give a convex angle ; hence, but one regular polyedron can be formed of squares. 3d. In the dodecaedron the polyedral angle is formed of three regular pentagons. The combination of more than three such angles (each angle being f of a right angle) exceeds four right angles, and will not give a convex angle ; hence, but one regular polyedron can be formed of pentagons. 4th. Three or more angles of a regular hexagon (each angle being f of a right angle) exceeds a right angle, and cannot form a convex polyedral angle ; and the same is true of the heptagon, octagon, etc. Therefore, only the five regular polyedrons named above PRACTICAL EXAMPLES. 1. Required the convex surface of a right prism whose altitude is 14 inches and perimeter of the base 16 inches. Ans. 224 square inches. 2. Required the contents of a prism the area of whose base is 24 square feet and altitude 7 feet. Ans. 168 cubic feet. 3. .Required the convex surface of a right pentangular pyramid whose Blant height is 18 inches and each Ride of the base 6 inches. Ans. 270 square inches. 4. Required the volume of the frustum of a square pyramid, the sides ef whose bases are 8 and 6 inches, and whose altitude is 12 inches. Ans. 592 cubic inches. 5. Required the entire surface of a cube whose sides are each H inches. Ans. 726 square inches. BOOK VI. 141 6. A man wishes to make a cubical cistern whose contents are 373248 cubic inches ; how many feet of inch boards will line it? Arts. 180 square feet. 7. What is the side of a cube which contains as much as a yolume 20 feet 6 inches long, 10 feet 8 inches wide, and 6 feet. 9 inches high ? Ans. 11.4 feet. 8. What is the depth of a cubical cistern which shall contain 1600 gallons, each 231 cubic inches of water! Ans. 5.98 feet. 9. Required the dimensions of a cube whose surface shall be nu- merically equal to its contents. Ans. 6 units. 10. There are two similar prisms whose lengths are as 7 to 28 re- spectively ; required the relation of their contents. Ans. 1 : 64. 11. Required the contents of a pyramid whose altitude is -20 inches and whose base is a regular hexagon, each side being 6 inches. Ans. 623.5386 cubic inches. 12. If we pass a plane parallel to the base of the pyramid of the 11th problem, half-way between its vertex and base, required the convex surface and contents of the frustum. Ans. Vol. = 545.596 cubic inches. 13. A farmer wishes to know what must be the depth of a cubical box which shall contain 100 bushels of grain, each bushel 2150.42 cubic inches. Ans. 4.9 feet. THEOREMS FOR ORIGINAL THOUGHT. 1. Parallelopipedons having equal bases and equal altitudes are equal in volume. 2. The diagonals of a rectangular parallelopipedon are equal. 3. If a plane be passed through the opposite edges of a rectangular parallelopipedon, the triangular prisms formed are equal. 4. Two prisms having the same base are to each other as their alti- tudes. 5. Two similar pyramids are equal when the base and lateral edge of the one equal the base and lateral edge of the other. 6. The surfaces of similar polyedrons are to each other as the squares sf their homologous edges ^ BOOK VII. THE CYLINDER, THE CONE, AND THE SPHERE. 1. A Cylinder is a volume which may be generated by the revolution of a rectangle about one of its sides as an axis. Thus, if the rectangle ABCD be revolved around the side AB as an axis, it will generate the cylinder ^-r—^. in the margin. The line AB is called the axis; the surface described by CD is called the convex surface; the circle .BCis the lower base ; the circle AD is the upper base. It is evident that the circle described by the line EF perpendicular to the axis is equal to either base ; hence, if a cylinder be cut by a plane parallel to the base, the section will be a circle equal to the base. 2. A Cone is a volume which may be generated by the revolution of a right-angled triangle about one of its sides adjacent to the right angle. Thus, if the right-angled triangle SBA be revolved around SB as an axis, it will generate the cone ADE—S. The side SB is the axis of the cone ; the circle described by AB is the base ; the hypothenuse SA is the slant height; the surface generated by SA is the convex surface. it is evident that the circle described by any line MN< perpendicular to the 142 BOOK VII. 143 axis is a circle ; hence, the section of a cone by a plane parallel to the base is a circle. 3. A Frustum of a Cone is the part which remains after cutting off the top with a plane parallel to the base. Thus, ADC— G is the frustum of a cone; FB is its altitude; FA is its slant height. The frustum of a cone may be generated by the revolution of the trapezoid ABFE. 4. Similar Cylinders or Cones are those whose axes are proportional to the radii or the diameters of their bases. 5. A prism may be inscribed in a cylinder by inscribing similar polygons with their sides parallel m each base, and uniting the vertices of the angles with straight lines. The cylinder is then said to circumscribe - the prism. 6. A pyramid may be inscribed in a cone; and a frustum of a pyramid may be inscribed in the frustum of a cone. 7. ASpHEREisa volume bounded by a curved surface, every point of which is equally dis- tant from a point within, called the centre. The distance from the centre to the circumference is called the , radius. The diameter is a line pass- ing through the centre and limited at both extremities by the surface. 8. A Spherical Sector is a volume generated by the revolution of a sector of a circle about the diameter. Thus, the revolution of ACF will generate a spherical sector. 9. A Z o n e is a portion of the surface of a sphere in- 144 GEOMEi'KY. eluded between two parallel planes. The bounding lines of the zone are called its bases; the distance between the planes is its altitude. 10. A Spherical Segment is a portion of the sphere included between two parallel planes. 11. If a semi-circumference be divided into equal arcs, the chords of these arcs form half of the perimeter of an inscribed polygon. The half perimeter is called a regular semi-per- imeter. The figure bounded by the diameter of the semi-circle and the regular semi-perimeter is called a regular semi-polygon. The diameter is called the axis' of the se^ni-polygon. 12. The Cylinder, the Cone and the Sphere are the Three Eound Bodies of Geometry. Analysis. — This book treats of the cylinder, the cone, and the sphere. Its object is to find the convex surface and volume of each of these bodies, and also their relation to each other. The method of treatment consists in regarding these volumes as polyedrons of an infinite number of sides. Thus, the cylinder is re- garded as a right prism of an infinite -number of sides, the cone as a right pyramid, and the sphere as a polyedron having its centre at the centre of the sphere. BOOK VII. 145 CYLINDER, CONE, AND FRUSTUM. THEOREM I. The convex surface of a cylinder is equal to the circumference of its base multiplied by its altitude. Let ABDE be the base of a cylinder whose altitude is H; then will its convex surface be equal to circumference CA X S. For, inscribe in the cylinder a prism whose base is a regular polygon. Now, the convex surface of this prism will be equal to the perimeter of its -base multi- plied by its altitude (B. VI. Th. I.) ; and this is true whatever the number of sides ; hence, it is true when the number of sides is infinite. But when the number of sides is infinite, the convex surface of the prism becomes the convex surface of the cylinder, the perimeter of the base of the prism becomes the circum- ference of the base of the cylinder, and the altitudes being the same, therefore, the convex surface of the cylinder equals the circumference of its base multiplied by its alti- tude. Cor. 1. Since the circumference of the base is 2 nB, the expression for the convex surface of a cylinder is 2 nBxS. Cor. 2. The convex surfaces of cylinders which havs equal altitudes are to each other as the circumferences of their bases. 18 146 GEOMETRY. THEOREM II. The volume of a cylinder is equal to the area of its base multi- plied by the altitude. Let ABD — F be a cylinder, whose altitude is Sj then will its volume be equal to the area of its base multiplied by its altitude. For, inscribe in the cylinder a prism whose base is a regular polygon. Now, the volume of this prism is equal to its base multiplied by its altitude (B. YI. Th. IX.), and this is true whatever the number of sides, and therefore true when the number of sides is infinite. But when the number of sides is infinite, the prism coincides with the cylinder in every respect ; hence, the volume of the cylinder is equal to its base multiplied by its altitude. Therefore, etc. Cor. 1. Since the area of the base is xB*, the expression for the volume of a cylinder is %B? X S. Cor. 2. Cylinders are to each other, as the products of their bases and altitudes. Cylinders having equal' bases are to each other as their altitudes; cylinders having equal altitudes are to each other as their bases. Cor. 3. Similar cylinders are to each other as the cubes of their altitudes, or of the radii of the bases. Let the pupil prove it. THEOREM III. The convex surface of a cone is equal to the circumference of its base multiplied by one-half of the slant height. Let # — ABCD be a cone whose base is ABB and slant tyeight SA; then will its convex surface be equal to the BOOK VII. 147 circumference of its base multiplied by one-half of its slant height. For, inscribe . in the cone a right pyramid. The convex surface of this pyramid is equal to the perimeter of its base multiplied by one-half of the slant height (B. VI. Th. XII.); and this is true whatever the number of sides of the base ; hence, it is true when the number of sides is infinite. But when the number of sides is infinite, the pyramid coincides with the cone in every respect ; hence, the con- vex surface of the cone is equal to the circumference of its base multiplied by one-half of the slant height. Cor. 1. If S represents the slant height, the expression for the convex surface of a cone is 2 nB X iS, or -kR X S. THEOREM IV. The volume of a cone is equal to the base multiplied by one- third of the altitude. Let S — AJBCD be a cone whose base is ABQD and alti- tude SO; then will its volume be equal to its base multiplied by one-third of its altitude; For, inscribe in the cone a right pyramid. The volume of this pyramid is equal to the base ABGD multiplied by one-third of its altitude 80 (B. VI. Th. XVII.) ; and this is true whatever the number of sides of the base ; hence, it is true when the number of sides is infinite. But when the number of 148 GEOMETRY. sides of the base is infinite, the pyramid becomes tha cone; hence, the volume of a cone is equal to its base multiplied by one-third of its altitude. Therefore, etc. Cor. 1. The expression for the volume of a cone is wiJ 2 X { S, or, I *W X B.. Cor. 2. A cone is one-third of a cylinder having an equal base and altitude. Cor. 3. Cones are to each other as the products of their bases and altitudes ; cones having equal bases are to each other as their altitudes ; cones having equal altitudes are to each other as their bases. THEOREM V. The convex surface of a frustum of a cone is equal to one-half of the sum of the circumferences of the upper and lower bases multiplied by the slant height. Let ABBE — H be a frustum of a cone, C its altitude, FA its slant height; then will its convex surface be equal to one-half the sum of the circumferences of its two bases mul- tiplied by its slant height. For, inscribe within the frustum of a cone the frustum of a right pyramid. The convex surface of this frustum is equal to one-half the sum of the peri- meters of its bases multiplied by the slant height (B. YL Th. XIX.) ; and this is true whatever the number of lateral faces ; hence, it is true when the number of faces is infinite. But when the number of faces is infinite, the frustum of a pyramid becomes the frustum of a cone, the perimeters of its bases become the circumferences of the bases of the BOOK VII. 149 frustum of the cone, and the slant height of the frustum of a pyramid becomes the slant height of the frustum of a cone ; hence, the convex surface of the frustum of a cone equals one-half the sum of the circumferences of its bases multiplied by the slant height.- „ Gor. The expression for the convex surface of a frustum of a cone is £ (2 nB -\- 2 tcB') X S, where B and B' repre- sent the radii of the bases, and S the slant height. Scholium. Through L, the middle point of HE, draw LK parallel to EG, and HB and LS perpendicular to EG; now BS= SE (Bk. III. Th. IX.) ; OH-= CB, and KL = CB + BS (Bk. I. Th. XV. C. 2). But CB + BS=SE + OH; hence, KL = \ (CB + BS+ SE+ OH) or i (CE + OH). Multiplying this by 2n, we have, 2 t:KL = 1(2 izGE + 2 nOH); that is, circ. KL equals £ of the sum of the circumferences of the two bases ; hence, the convex surface of the frustum, of a cone, generated by the revolution of the line HE, is equal to the circumference of a circle generated by its middle point into the length of the line. THEOREM VI. The volume of the frustum of a cone is equal to the sum of the volume of three cones, having for a common altitude the alti- tude of the frustum, and for bases the two bases of the frustum and a mean proportional between them. Let ABDE—H be a frustum of a cone, OG its altitude; then will its volume be equal to the sum of the volumes of three cones whose common altitude is OG, and whose bases are the two bases and a mean proportional between them. 13* 150 GEOMETRY. f/y *\ rr / / / / a \ / / / / "^4 For, inscribe in the frustum the frustum of a right pyramid. The volume of this frustum is equal to the sum of the volumes of three pyramids having the common altitude of the frustum, and whose bases are the two bases of the frustum and a mean pro- portional between them (B. VI. Th. XX.) ; and this is true whatever the number of lateral faces, and, hence, true when the number of faces is infi^ nite. But when the number of lateral faces is infinite, the frustum of the pyramid becomes the frustum of a cone, and the three pyramids become cones; hence, the volume of the frustum of a cone equals the sum of the volumes of three cones, whose common altitude is the altitude of the frustum, and whose bases are the two bases of the frustum and a mean proportional between them. Cor. The expression for the volume of a frustum of a Vine is (nB? + nr 2 + tcR X r) X i H. THE SPHERE. THEOREM VII. Every section of a sphere made by a plane is a circle. Let C be the centre of a sphere whose radius is GA, and ADB any section made by a plane; then will this section be a circle. For, draw CO perpendicular to the section ABB, and draw the lines OD and OE to different points of the BOOK VII 151 curve ADB; draw also the radii CD and CE. Then, since the radii CD and CE are equal, the lines OD and OE must be equal (B. V. Th. III. C. 1); hence, the section ADB is a circle. Therefore, etc. * Cor. If the plane pass through the centre of the sphere, the radius of the section will be equal to the radius of the sphere. The section is then called a great circle. All other sections are called small circles. THEOKEM VIII. If a regular semirpolygon be revolved about its axis, the surface generated by the semisperimeter.urill be equal to the circumfer- ence of the inscribed circle multiplied by the axis. TjetABCDFF be a regular semi-polygon, AF the axis, ON the radius of the inscribed circle ; then will the surface generated by the revolution of the semi-polygon be equal to circ. ON X AF. For, from the extremities of any side, as BC, draw BGr and CH perpendicular to AF; fromiV", the middle point of BC, draw NM perpendicular to AF; draw also BL per- pendicular to CH. Now, the surface de- scribed by BC is equal to circ. MN X .BC (Th. V. S. ). But, since the triangles BCL and NOM are similar, we have, BC: BL or CH : : ON: NM : : circ. ON : circ. NM; hence, circ. NM X BC = circ. ON X CH; that is, the surface generated by BC is equal to the cir- cumference of the inscribed circle multiplied by the alti- tude CH; and the same may be shown for each of the other sides; hence, the surface described by the entire 152 GEOMETRY. semi-perimeter is equal to the circumference of the inscribed circle multiplied by the sum of AG, GR,Hl, etc., or the axis AF. Therefore, etc. Cor. The surface described by any portion of the peri- meter, as BCD, is equal to circ. ON X Gtl. THEOREM IX. The surface of a sphere is equal to the circumference of a great circle multiplied by the diameter. Let ABCDJEF be a semicircle, its centre, and AF its diameter; then will the surface of the A sphere generated by the revolution of the B ^^ semi-circumference about the diameter be /fa equal to circ. OA X AF. c f~~^- For, inscribe in the semi-circumference a regular semi-polygon. The surface de- X- scribed by the revolution of the polygon is \ equal to circ. OH X AF (Th. Yin.); and ^^ this is true whatever the number of sides ; hence, it. is true when the number of sides is infinite, in which case the volume becomes a sphere with the radius OA; hence, the surface of a sphere is equal to circ. OA X AF. Therefore, etc. Cor. 1. The surface of a sphere is equal to four of its great circles. For, sur. = circ. OA X 2 OA; but circ. OA = 2 kOA; hence, sur. = 2 nOA X 2 OA; which gives sur. = 4 nOA 2 ; but xOA 2 is the area of a great circle ; hence, 4 nOA 2 is the area of four great circles. Cor. 2. The expression for the surface of a sphere is 4 itR\ or 7rZ> 2 , in which B, is the radius and D the diameter. Cor. 3. The surfaces of spheres are to each other as the BOOK VII. 153 squares of their radii or diameters. For, sur. S = 4 tcB?, and sur. s == 4 tit 2 ; hence, S: s : : 4 ttJB 2 : 4 Ttr 2 , oriZ 2 : r 2 . Cor. 4. The surface of a zone is equal to the circumfe- rence of a great circle multiplied by its altitude. Cor. 5. Zones on the same sphere, or on equal spheres, are to each other as their altitudes. A zone is to the surface of a sphere as the altitude of the zone is to the diameter of the sphere. THEOREM X. The volume of a sphere is equal to its surface multiplied by one-third of its radius. For, conceive a regular polyedron to be inscribed in a sphere ; this polyedron may be conceived as consisting of pyramids having their vertices at the centre of the sphere, and for bases the taces of the polyedron. The volume of each of these pyramids is equal to its base multiplied by one-thin? of its altitude, and, their altitudes being equal, the volume of the polyedron will be equal to the sum of all their bases, which is the surface of the polyedron, multiplied by one-third of the common altitude. Now, the sphere may be regarded as a polyedron consisting of an infinite number of pyramids, hav- ing their vertices at the centre of the sphere and their bases at its surface, their altitudes being equal to the radius of the sphere ; hence, the volume of a sphere is equal to its surface multiplied by one-third of the radius. Cor. 1. If we represent the volume of a sphere by vol. S, and the surface by sur. S, we will have, vol. 8 = sur. SXiRj and since sur. S= 4 n/J 1 we have, vol. S=i kB 2 X iB; which, reduced, 154 GEOMETRY. gives, (1) vol. S — i itR'. But, B = £ B, or R* = £ B 3 , Hence, (2) vol. 8=1*1?. Cor. 2. Spheres are to each other as the cubes of tlnsir radii, or diameters. Cor. 3. The volume of a spherical sector or pyramid is equal to its base multiplied by one-third of the radius. For the sector or pyramid may be conceived as consist- ing of an infinite number of pyramids having their ver- tices at the centre of the sphere, and the volume of the sum of these will be the sum of their bases multiplied by one-third of the radius. Cor. 4. The volume of a spherical segment of one base and less than a hemisphere, as that gene- rated by A CB revolving about AF, is equal to the volume of the spherical sector AOC minus the volume of the cone formed by OCB. The volume of a spherical segment of one base and greater than a hemisphere, as AEB, is equal to the volume of the spheri- cal sector AOE plus the volume of the cone formed by EBO. The volume of a spherical segment of two bases, as that generated by BCED, is equal to the volume of the sector, formed by COE, plus the volume of the cones formed by OCB and OED. If the points C and E fall on the same side of the centre, the last cone must be subtracted. Ths measure is as follows : Segment BCED = zone CE X i OC + idffi 1 X i OB + «nE 2 X I OB. BOOK VII. 155 THEOREM XI. The surface of a sphere is to the entire surface of the, circum- scribed cylinder, including its bases, as 2 to 3; and their volumes are to each other in the same ratio. Let AE be a cylinder circumscribed about a Bphere whose centre is P; then, First. The surface of the sphere is to the entire surface of the cylinder as 2 is to 3. For, the surface of the cylinder equals circumference AO X OG (Th. I.) ; that is, the circumference of a great circle of the sphere multiplied by the diameter of the sphere ; but this is equal to the surface of a sphere (Th. IX.) ; hence, the surface of the cylinder equals the surface of the sphere ; but the surface of the sphere equals four great circles ; hence, the convex surface of the cylinder equals four great circles, and adding the two bases, we have the entire surface of the cylinder equal to six great circles ; hence, the surface of the sphere is to the surface *of the cylinder as 4 great circles is to 6 great circles, or as 4 to 6, or 2 to 3. Second. The volume of the sphere is to the volume of the cylinder as 2 is to 3. For, the volume of the sphere is | tt-B 3 (Th. X. C. I.), and the volume of the cylinder is ttJK 2 X GO (Th. II.), or xR* X 2 R = | t-R 3 ; hence, or, vol. 8. : vol. cyl. . : 4 tzR 3 : | wifr • : 4 : 6, or 2 Therefore, etc. 156 GEOMETRY. PRACTICAL EXAMPLES. 1. Required the convex surface and contents of a cylinder whost altitude is 16 inches, and diameter of the base 8 inches. Am. 402.12; 804.25. 2. Required the convex surface and volume of a cone whose altitude is 24 inches, and radius of the base 10 inches. Ana. 816.816; 2513.28. 3. Required the convex surface of the frustum of a cone whose alti- tude is 36 inches, the radius of the upper base 6 inches, and lower base 21 inches. Am. 3308.1048. 4. Required the volume of a frustum of a cone whose altitude is 9 feet, diameter of lower base 4 feet, and of upper base 2 feet. Am. 65.9736. 5. Required the surface and contents of a sphere whose diameter is 16 inches. Am. 804.2496 ; 2144.6656. 6. The surface of a sphere is 1809.5616 square inches; required its diameter and its volume. Am. D. = 24 inches. 7. The volume of a sphere is 113.0976 cubic inches; required its diameter and its surface. Am. D. = 6 inches. 8. Given the volume of a sphere 268.0832 cubic inches; required the altitude of the circumscribing cylinder. Am. 8 inches. 9. What is the surface of a zone of a single base whose altitude is 10 feet, the diameter of the sphere being 100 feet? Am. 3141.6 sq. ft. 10. Required the volume of a. spherical segment of one b«Se whose altitude is 2 feet, the diameter of the sphere being 8 feet. Am. 41.888 cubic feet. 11. Required the volume of a spherical segment whose greater dia- meter is 24 inches, less diameter 20 inches, and distance of bases 4 inches. Am. 1566.6112 cubic inches. THEOREMS TOR ORIGINAL THOUGHT. 1. Prove that two great circles of a sphere bisect each other. 2. Prove that every great circle divides the sphere into two equal parts. BOOK VII. 157 3. Prove that the centres of a small circle and the sphere are in a tine perpendicular to the small circle. 4. Prove that the radius of a small circle is less than the radius of the sphere. 5. Prove that circles whose planes are equidistant from the centre ire equal. 6. Prove that the intersection of two spheres is a circle. 7. Prove that the arc of a great circle may be made to pass through any two points on the surface of a sphere. 8. Prove that if a cone and sphere he inscribed in a cylinder, that these bodies are to each other as 1, 2, and 3. MISCELLANEOUS PROBLEMS. — PLANE FIGURES. 1. How many bricks 8 inches long and 4 inches wide will it take to pave a yard 20 feet by 16 feet? Ans. 1440. 2. How much will it cost to plaster a room whose length is 24 ft., width 18 ft., and height 12 ft., at 16 cts. a square yard? Arts. $25.60. 3. What is the difference in area between a rectangle 60 feet by 40 feet, and a square which has the same perimeter ? Ans. 100 sq. ft; 4. What is the diagonal of » square whose area is equal to the area of a rectangle 16 inches by 25 inches ? Ans. 28.28 inches. 5. The diagonal of a square is y/50 inches ; required the side of the square. Ans. 5 inches. 6. Required the diagonal of a room whose length is 48 feet, width 20 feet, and height 39 feet. Ans. 65 feet. 7. A vessel' sailed north 20 miles, then west 30 miles, then north 60 miles, then west 70 miles ; how far was it then from the point at which it started ? . A™- 128.06 miles. 8. The gable ends of a house are 48 ft. wide, and the ridge-pole is 10 ft. above the eaves ; required the length of the rafters. Ans. 26 ft. 9. Required the area of an isosceles triangle whose base is 20,feet, and each of its equal sides 15 feet. Ans. 111.803 square feet. 10. A flag-staff was broken, and fell, the broken part resting upon the upright, so that the end struck 48 feet from the foot ; the upright part measured 36 feet ; how long was the staff ? Ans. 96 feet. 14 158 GEOMETRY. 11. I wish to enclose a square rod in the form of an equilateral tri angle ; what must be the length of each side ? Ans. 25.076. 12. Given the area of a circle 19.635 square inches ; required the diameter and circumference. Ans. D. = 5 inches. 13. The equal sides of an equilateral triangle are each 16 feet ; what is the side of the inscribed square ? Am. 7A25. 14. I have a plank 12 feet long which contains 15 square feet ; what is the width of each end, if they are as 2 to 3 ? Ans. 12 in. ; 18 in. 15. If th,e minute-hand of a clock is 6 inches long, over how much space does it pass in 40 minutes ? Ans. 75.398 square inches. 16. What is the circumference of a circle whose diameter equals the diagonal of a square which contains 25 sq. rds. ? Ans. 22.211112. 17. What is the diameter of a wheel which makes 200 revolutions in a minute, when the cars are going 30 miles an hour ? Ans. 4£ -|- feet. 18. A horse is fastened in a meadow, by a halter 20 feet long, to the top of a post 6 feet high ; what is the area of the circle over which he can graze ? Ans. 127.06 square yards. 19. Required the area of a circle in which the number expressing its. area equals the number expressing its circumference. Ans. 12.5664. 20. The area of a circular park is 4 acres ; how long will it take to , drive round it at the rate of 6 miles an hour ? Ans. 2 min. 48 sec. 21. A circular garden containing 2 acres is bordered by a gravel walk of uniform width, which takes up \ of its area; required the width of the walk. Ans. 22.308 feet. 22. If the hour-hand of a clock is 4 inches long, and the minute- hand 6 inches, what is the difference of the surfaces over which they travel in an hour? Am. 108.91 square inches. MISCELLANEOUS PROBLEMS. — VOLUMES. l._ Required the surface, of a brick 8 inches long, 4 inches wide, and 2 inches thicks Ans. 112 square inches. 2. Required the entire surface of a right pyramid whose base is a square 4 in. long, and the slant height 12 inches. Ans. 112 sq. in. 3. Required the entire surface of a cylinder whose altitude is 16 in., the radius of the base being 6 inches. Ans. 829.3824 sq. in. BOOK VII. 159 4. Required the entire surface of a cone whose height is 16 feet, the radius of the base being 12 feet. Am. 1206.3744 sq. ft. 5. Required the surface and contents of a sphere inscribed in a cube whose edge is 20 inches ; and also the space between them. 6. The surface of a sphere is 6.305 square feet ; required its diameter and volume. Ans. Vol. 1.48868 cubic feet. 7. The volume of a sphere is 1.2411 cubic feet ; required the diameter •nd surface. Ana. D. 16 inches. 8. The convex surface of a cylinder whose altitude is 14 feet is 116.666 square feet; required the diameter of its base. Ans. 2.65 ft. 9. What is the volume of a cylinder whose height is 20 feet, and the circumference of the base is 20 feet also 1 Ans. 636.64 feet. 10. The volume of a cylinder is 15.708 cubic feet; what is the alti- tude, if the diameter of the base is 2 feet 1 Ans. 5 feet. 11. The convex surface of a cone is 141.372 square feet, and the dia- meter of the base 4.5 feet; required the slant height and altitude. ' Ans. 20 feet. 12. If a segment of 6 feet slant height be cut off of a cone whose slant height is 30 feet, the circumference of the base being 10 feet, what is the surface of the frustum ? Ans. 144 square feet. 13. The convex surface of a frustum is 376.992 square feet, the slant height 20 feet, and the diameter of the less end 4 feet; what is the diameter of the greater end ? Ans. 8 feet. 14. The volume of a cone is 8.83575 cubic feet, the altitude 15 feet; what is the diameter of the base ? Ans. 18 inches. 15. The volume of a frustum of a cone is 65.9736 cubic feet, the diameter of one end is 4 feet and of the other 2 feet; required the altitude. Ans. 9 feet. 16. Required the entire surface of the frustum of a cone whose height is 12 feet, the radius of the lower base being 9 feet and the upper base 4 feet. Ans. 266 jr. 17. Required the entire surface of the frustum of a pyramid whose bases are squares, the lower 9 feet, the upper 4 feet, on a side, the alti- tude being 12 feet. Ans. 415.68 sq. ft. 18. How far must a person ascend above the earth that he may see one-third of the surface ? Ans. 2 times the radius. BOOK VIII. SPHERICAL GEOMETRY. 1. Sphericjal Geometry has for its object the invest tigation-of the properties and relations of those portions of the surface of a sphere which are bounded by arcs of great circles. 2. A Spherical Angle is an angle included between the arcs of two great circles meeting at a point. The arcs are called sides, and the point at which they meet the vertex of the angle. The measure of a spherical angle is the same as that of the diedral angle included between the planes of its sides. Spheri- cal angles may be acute, right, or obtuse. 3. A Spherical Polygon is a portion of the surface of a sphere bounded by arcs of great circles. These arcs are called the sides of the polygon, and the points in which they meet the vertices. Each arc is supposed to be less than a semi- circumference. 4. A Spherical Triangle is a spherical polygon of three sides. Spherical triangles are classified in the same man- ner as plane triangles. 5. A Lune is a portion of the surface of a sphere bounded by two semi-circumferences of great circles. 8. A Spherical "Wedge is a portion of a sphere bounded oy a lune and the planes of its two sides. 7. A Spherical Pyramid is a portion of a sphere bounded by a spherical polygon and the circular sectors formed upon the sides of the polygon. The spherical polygon is called the base of the pyramid, and the centre of the sphere is called the vertex. 160 BOOK VIII. 161 8. A Pole of a Circle is a point on the surface of the sphere equally distant from all points of the circumference of the circle. 9. A Diagonal of a spherical polygon is an arc of a great circle joining the vertices of any two angles not consecutive. 10. The Supplement of an arc is what the arc lacks of Being a semi-circumference. x THEOEEM I. Any side of a spherical triangle is less than the sum of the other two. Let AB G be a spherical triangle, being the centre of the sphere; then will any side, as AB, be less than the sum of the sides A G and BG. For, draw the radii OA, OB, and OG, forming a triedral angle whose vertex is 0; then the plane angle A OB is less than the sum of the angles A OG and BOG (B. V. Th. XII.) ; hence the arc AB, which measures A OB (B. IV. Th. VIII.), is less than AG + BC, which measure AOC+BOG. Therefore, etc. THEOEEM II. Any side of a spherical polygon is less than the sum of the oiher 'Let ABODE be a spherical polygon; then will any side, as iE, be less than the sum of AB, BG, CD, and BE. For, draw the diagonals BE and CE, dividing the polygon ABODE into tri- a( angles. The arc AE is less than the sum of AB and EB, EB is less than the sum of BG and EC, and EC is less than the sum of ED and DO 14* 162 GEOMETKY. (Th. I.) ; hence AE is less than the sum of AB, BC, CD, and DE. Cor. The are of a great circle measures the shortest distance between two points on the surface of a sphere. For, if wS divide any arc of a small circle joining the two points into equal parts, and through their extremities pass arcs of a great circle, the arc of the great circle joining the twc given points will be less than the sum of these arcs (Th. II.). When the number of arcs becomes infinite, their sum is equal to the arc of the small circle. Therefore, etc. THEOKEM III. Tlie sum of the sides of a spherical polygon is less than the cir- cumference of a great circle. Let ABCDE be a spherical polygon, and the centre of the sphere ; then will the sum of its sides be less than the circumference of a great circle. / For, draw the radii OA, OB, OC, OD, and A OE, forming a polyedral angle whose vertex is \ 0; then the sum of the plane angles AOE, EOD, DOC, COB, and BOA is less than four right angles (B. V. Th. XIII.) ; hence the sum of the arcs which measure them is less than the circumference of a great circle, which is the measure of four right angles. Therefore, etc THEOKEM IV. If a diameter of a sphere be drawn perpendicular to the plane of any circle of the sphere, its extremities will be poles of that circle. Let CFD be any circle of a sphere, and AB a diameter of the sphere perpendicular to the plane of CFD ; then will A and B be the poles of the circle CFD. BOOK VIII. 163 The diameter AB, being perpendicular to the plan* of CFD, must pass through the centre E, since the diameter CD is a chord of the great circle ADBC, and must therefore be bisected by a diameter perpendicular to it (B. IV. Th. III.). If arcs of great cir- cles A C, AF, and AD be drawn from A to different points of the circumference CFD, the chords of those arcs will be equal (B. V. Th. III.) ; hence the arcs will be equal. But these arcs are the shortest lines that can be drawn from A to the points of the circumference (Th. II. Cor.) ; hence A, being equally distant from all points of the circumfer- ence, is a pole of the circle CFD (Def. 8). It may be proved in like manner that B is also a pole of the circle. Therefore, etc. Cor. 1. The poles of a great circle are at equal distances from the circumference ; and those of a small circle are at unequal dis- tances, the sum of the distances being equal to the semi-circumfer- ence of a great circle. For, let CHI be a great circle perpendicular to AB; then will the angles A OH, B OH, etc., be right angles, and the arcs AH, BH, etc., will be quadrants (B. V. Th. IX. C). The arc A C is less than a quadrant, and BC is greater than a quadrant, and their sum equals A CB. Cor. 2. If any point in the circumference of a great circle is joined with either pole by the arc of a great circle, the latter arc will be perpendicular to the circumference of the given circle. For, the line A being perpendicular to the plane CHI, any plane, as A OH, passed through it, will also be perpendicular to the plane CHI; hence the spherical angle AHC is a right angle, and the arc AH is perpendicular to the circle GHI. 164 GEOMETRY. Cor. 3. A point on the surface of a sphere at the distance of a quadrant from two points in the arc of a great circle, not at the extremities of a diameter, is a pole of the arc. For, since the arcs AG and AH are quadrants, the angles AOG and A OH are right angles, and the line OA is perpen- dicular to the straight lines G and OH; hence OA is a radius perpendicular to the plane GHI (B. V. Th. IV.), and the point A is therefore a pole of the arc HG. /Scholium. By means of poles we may with facility describe arcs of a circle on the surface of a sphere. For, revolving the arc A C around the pole A, the extremity C will describe the small circle CFD ; and by revolving the quadrant AG around the pole, the extremity G will describe the great circle 'GHI. THEOREM V. The angle formed by the intersection of two arcs of great circles is equal to the angle included between the tangents to these arcs at the point of intersection, and is measured by the arc of a great circle described from the vertex as a pole, and limited by the sides, produced if necessary. Let the angle BA G be formed by the intersection of the two arcs AB and A G; then it is equal to the angle HA G formed by the tangents AH and A G, and is measured by the arc ED of a great circle described from A as a pole. For, the tangent A G, drawn in the plane of the arc AC, is perpendicular to the radius AO; and the tangent AH, drawn in the plane of the arc. AB, is also perpen- dicular to the radius A 0; hence the angle BOOK VIII. 165 SAG is equal to the angle formed by the planes ABDF and A CEF (B. V. Def. 6), which is the angle formed by the arcs AB and A C. Now, if the arcs AD and AE are both quad- rants, the lines OD and OE are perpendicular to A 0, and the angle DOE is equal to the angle of the planes ABDF and A CEF; hence the arc DE, which is the measure of D OE, is also the measure of B A C. Cor. The opposite or vertical angles formed by two arcs of great circles intersecting each other are equal, and the sum of any two adjacent angles is equal to two right angles. Scholium,. The angles of spherical triangles are compared by means of the arcs of great circles. described from their vertices as poles and included between their sides. Thus a spherical angle can always be constructed equal to a given angle. THEOREM VI. If from the vertices of the angles of a spherical triangle, as poles, ares be described forming a spherical triangle, the vertices of the angles of the second triangle will be respectively poles of the sides of the first. From the vertices A, B, C as poles describe the arcs DE, EF, FD, forming the triangle EFD; then will the vertices D, E, F be respectively poles of the sides BC, AC, AB. For, since the point A is the pole of the arc EF, the distance AE is a quadrant ; and since the point C is the pole of the arc DE, the distance CE is a quadrant ; hence the point E is at a quadrant's distance from A and C, and therefore it is the pole of the arc AC (Th. IV. Cor. 3). In the same manner it may be shown that D is the pole of CB, and F the pole of AB. Therefore, etc. 166 GEOMETKY. Scholium. The triangle ABC may be described when DEF is given, as DEF is described when ABC is given. Triangles thus related are called polar triangles or supplemental triangles. Since great circles intersect each other in , , . , . e\- -.. d ,--- if two points, three other triangles may be > % y ■ formed by producing the arcs DE, FE '''-•{- \<'' zndFD; but the central triangle only is > i taken as a polar triangle, being the only \ / one in which the vertices A and D are on «* the same side of BC, the vertices B and E on the same side of AC, and the vertices Cand F on the same side of AB. THEOKEM VII. In two polar triangles, any angle of one triangle is measured by the supplement of the side lying opposite to it in the other. Let AB G and DEF be two polar triangles ; then will any angle of either triangle be measured by the supplement of the side lying opposite to it in the other. For, produce AB and A C, if necessary, till they meet EF in H and G. Since A is the pole of EF, the angle A is meas- -EL ured by the arc GH (Th. V.). But since E is the pole of AG, the arc EG is a quadrant ; and since F is the pole of AH, the arc FHia a quadrant, and the sum of the arcs EG and FH is a semi-circumference. But EG + FH = EF + GH; hence the arc GH, the measure of the angle A, is equal to a semi-circumference minus the arc EF. In the tame manner it may be proved that the measure of any other angle in either triangle is the supplement of the side lying opposite to it in the other. BOOK Vlir. 167 THEOREM VIII. The sum of the angles of a spherical triangle is less than six right angles and greater than two. For, any angle, being measured by the supplement of the side lying opposite to it hi -the polar triangle (Th. VII.), is less than two right angles ; hence the sum of the three angles is lesa than six right angles. Also, the measure of the sum of tho three angles is equal to three semi-circumferences minus the three sides of the polar triangle. But the three sides of a tri- angle are less than a circumference (Th. III.) ; hence the meas- ure of the sum of the three angles is greater than a semi-cir- cumference, and the sum of the angles is greater than two right angles.. Therefore, etc. Cor. 1. A spherical triangle may have two, or even three, right angles j'also two, or even three, obtuse angles. Cor. 2. If the triangle ABC has two right angles, it is called bi-rectangular. Since the arcs AB and A C are perpendicular to BC, they must both pass through the pole of BC; hence their point of intersection, A, is the pole, and the arcs AB and A C are quad- rants. If the angle A is also a right angle, the triangle is tri-reet- angular, the sides being quadrants. Four tri-rectangular tri- angles make up the surface of a hemisphere, and eight that of a sphere. Scholium. The sum of the three angles of a spherical triangle is not constant, like that of the angles of a plane triangle, but varies between two right angles and six without ever reaching either limit. Two angles, therefore, being given, do not serve to determine the third. The excess of the sum of the angles over two right angles is called the spherical excess, and taking .168 GEOMETBY. the right angle as the unit may be represented thus : A -f- B + C — 2 = spherical excess. THEOREM IX. Two spherical triangles on the same sphere or on equal spheres are equal — 1. When two sides and the included angle of the one are equal to two sides and the included angle of the other. 2. When two angles and the included side of the one are equal to two angles and the included side of the other. 3. When the three sides are respectively equal. The three cases of this theorem may be demonstrated, as in plane triangles, by applying one of the given triangles to the tther or to its symmetrical triangle. Scholium. The symmetrical triangle is formed thus : Let AB, BQ and AC be three arcs of great circles, from which either of the two triangles ABC, ABC may be formed. These two triangles, although all their parts are equal, are not capable of su- perposition, because in inverting one in order to bring the corresponding parts together the con- vex surfaces would be turned toward each other, angles are called symmetrical triangles. Cor. The circles passed through the vertices of two mutually equilateral triangles on the same sphere or on equal spheres are equal. For, the plane triangles formed by the chords of the sides of these spherical triangles must be equal ; hence, if the spherical triangles are applied 'to each other, the vertices of the spherical triangles will coincide, and the circles passing through the vertices are equal. BOOK VIII. 169 THEOEEM X. Two symmetrical spherical triangles are equal in area. Let ABO and DEF be two symmetrical triangles, jn which AB equals DF, A C equals DE, and CB a d equals EF.. Then will the area of the /f\ JV\ two triangles be equal. / \ / | \ For, let G be the pole of the small \^~t/ \\ J circle passing through the points A, B, B p and C, and IT the pole of the circle passing through D, E, and F; these circles will be equal (Th. IX., C). Join A, B, and C with G, and D, E, and F with 27, by arcs of great circles ; these arcs will all be equal, since -they measure the distances from the circumferences of equal circles to their poles. The triangles ACG and DEH, being isosceles and having equal sides, may be applied to each other, and are equal in area ; so also CB G is equal to EFH, and AB G to DFH. Hence A CG + CBG — ABG = DEE + EFH— DFH, or, reducing, ABG=: DEF. Therefore, .etc. Scholium. If the point G fall within the triangle A CB the point H will also fall within the triangle DEF, and the areas of the triangles will equal the sum of the three isosceles tri- angles. THEOEEM XL If two triangles on the same, or on equal spheres, are mutually equiangular, they are also mutually equilateral. Since the two given triangles are mutually equiangular, their polar triangles must be mutually equilateral (Th. VII.), and consequently mutually equiangular (Th. IX.). But if these polar triangles are mutually equiangular, the given triangles are mutually equilateral (Th. VII). 15 170 GJEOMETKY. Scholium. This proposition does not extend to plane triangles, for similar plane triangles are not necessarily mutually equi- lateral. But two spherical triangles on the same or equal spheres cannot be similar without being equal. r T a \ yK £ THEOEEM XII. The surface of a lune is to the surfaee of a sphere as the angle of the lune to four right angles, or as the are which measures that angle is to the circumference of a great circle. Let ABGDA be a lune on the surface of a spherej and BD the arc of a great circle whose poles A are A and G, the vertices of the angles of the lune ; then will the sur- face of the lune be to the surface of ■Bl* the sphere as the arc BD to the cir- cumference BDEG. For, if we divide the arc BD and tfce circumference BDEG into equal parts, BF being one of those parts, and* pass planes through the diameter AG and each of the points of division, the surface of the sphere will evidently be divided into equal lunes, of which the given lune will contain as many as there are parts in the arc-BD; hence, the lune ABGDA is to the whole sur- face of the sphere as the arc BD is to the circumference BDEG ; and the same may also be shown when the arc BD and the cir- cumference are incommensurable. But BD is the measure- of the angle of the lune, and the circumference is the measure of four right angles. Therefore, etc. Cor. 1. Lunes on the same sphere or on equal spheres are to each other as their angles. Ppr. 2. Taking the right angle as the unit of angles, and BOOK VIII. 171 denoting the angle of a lune by A, the area by L, and the surface of a tri-rectangular triangle by T, we have L:8T::A:4; whence, L — T X 2 A. Therefore the area of a lune is equal to the tri-rectangular 'riangle multiplied by twice the angle of the lune. Cor. 3. A spherical wedge bears the same relation to the entire sphere as the angle of the wedge to four right angles, as may be shown by a similar course of reasoning to that em- ployed in the theorem ; hence the volume of the wedge is equal to the lune which forms Us base, multiplied by one-third of the "adius. THEOEEM XIII. If two circumferences of great circles intersect on the surface of o. hemisphere, the sum of either two of the opposite triangles thus formed is equal to a lune whose angle is equal to that formed by the circles. Let the circumferences AEBF, CEDE intersect on the sur- face of a hemisphere; then will the •» sum of the opposite triangles A EG, S/f \\ DEB be equal to the lune whose / / \ \ / / \D \ angle is AEG. v /---'/" ~"V, \ For, since AEB and EBF are semi- \H^_ ^Tj circumferences, if we take away the \ \ / / common part EB we have AE equal \\< y'\/ to BF. In the same way, we find f CE equal to JDF and BD equal to A C; hence the two triangles AEC and BFD, having their sides equal, must be symmetrical, and therefore equal in area (Th. X.). But the sum of the tri- angles DEB and BFD is equal to the lune EDFBE, whose 172 GEOMETKY. angle is AEC; hence the sum of AEC and DEB equals th« lune whose angle is AEG. Therefore, etc. Scholium. It is evident that the two spherical pyramids which have the triangles A CE and BED for bases are together equal to the spherical wedge, whose angle is AEC. THEOEEM XIV. The area of a spherical triangle is equal to its spherieal excesi multiplied by the trvredangular triangle. Let ABC be a spherical triangle; then, representing the tri-rectangular triangle by T, the sur- face of the given triangle will be equal to (4 +B+ 0—2) X T. For, produce the sides until they meet the circumference of a great circle, drawn without the triangle, forming three sets of opposite tri- angles. By the last theorem the area of each of these sets is equal to the lune whose angle is the cor- responding angle of the triangle. Hence (Th. XII., Cor. 2), ADF + AHI = 2 A X T. BEI + BFG = 2B X T. CGH + CDE = 2 C X E But the sum of these six triangles exceeds the hemisphere, or 4 T, by twice the triangle ABC; hence, by adding the equation: and substituting in the first member its value, we have 4T+2ABC=2AX T + 2B X T + 2 C X T; reducing, ABC = (A + B + C— 2) X T. But A -\- B -\- C — 2 is the spherieal excess of the triangle (Th. VIII. Seh.), and T is the tri-rectangular triangle. There- fore, etc. BOOK VIII. 173 THEOEEM XV. The area of a spherical polygon is equal to its spherical excess multiplied by the tri-rectangular triangle. Let ABODE be a spherical polygon. If we draw the diag» aals A C and AD, the polygon will be divided ;nto as many triangles as there are sides, less two. Now, the area of each triangle is equal to the sum of its angles minus two right angles, multiplied by the tri-rectangular tri- angle ; and the area of the polygon, or the sum of all the triangles, is equal to the sum of all the angles of the triangles, or the sum of the angles of the polygon, dimin- ished by two right angles, taken as many times as the polygon has sides, less two, and the difference multiplied by the tri- rectangular triangle ; which is the spherical excess of the polygon multiplied by the tri-rectangular triangle. Therefore, etc. Cor. If we represent the sum of the angles by S, and the number of the sides by n, we shall have the area of a polygon = [S — 2 (n — 2)] X T; and re- ducing have area of a polygon = (S — 2 n + 4) X T. PRACTICAL EXAMPLES. L Find the area of a spherical triangle each of whose angles is 70°. Ans. \ 7r E 2 . 2. Find the area of a spherical polygon of six sides each of whose Migles is 150°. Ans. it E 2 . 3. Given the spherical triangle whose angles are respectively 80°, 90°, and 140°, to find the sides of its polar triangle. Ans. 100°; 90°; 40°. 4. If the sides of a triangle" are respectively 75°, 110°, and 130°, what «re the angles of its polar triangle ? Ans. 105° ; 70° ; 50°. 15* 174 GEOMETRY. 5. "What is the area of a bi-rectangular triangle whose vertical angla ' is 108° ? . " Ans. | ■k W. 6. Find the area of a spherical triangle whose angles are 60°, 90°, and 120°, the diameter of the sphere being 8. Arts. 8 t. 7. Find the area of a lune, its angle being 45°. Am. J ir R 2 . 8. Find the area of a lune, the angle being 54° and radius of the sphere being 5. Ans. 15 ir. 9. Find the volume of a spherical wedge, the angle of the lune being 72°. Aiis. Jg tr R s . 10. Find the volume of a spherical wedge, the angle of the lune being 36° and the diameter of the sphere 10. Ans. lGf t. 11. Find the angles of an equilateral spherical triangle whose area is equal to the surface of a great circle. Ans. 120°. 12. What must be the angles of an equilateral spherical triangle that its area may be equal to an equilateral spherical hexagon, each of whose angles is 130° ? Am. 80°. THEOREMS FOE ORIGINAL THOUGHT. 1. Prove that in an isosceles spherical triangle the angles opposite the equal sides are equal. 2. Prove that a spherical triangle having two equal angles is isopceles. 3. In any spherical triangle the greater side is opposite the greater angle, and conversely. 4. If from any point of a hemisphere two arcs of great circles are drawn perpendicular to its circumference, the' shorter of the two arcs is the shortest arc that can be drawn from the given point to the circum- ference. 5. Two oblique arcs drawn from the same point to points of the cir- cumference at equal distances from the foot of the perpendicular are equal. 6. Of two oblique arcs, that which meets the circumference at the greatest distance from the foot of the perpendicular is the longer. 7. Prove that the area of a spherical triangle, each of whose angle* is | it a right angle, is equal to the surface of a great circle. MENSURATION. MENSURATION OF LENGTHS AND SURFACES. 1. Mensuration is the science which treats of the measurement of geometrical magnitudes. 2. The Area of a figure is its quantity of surface; it is expressed by the number of times which it contains the unit of measure. 3. This Unit of Measure is a square whose side is some known length ; as, an inch, a foot, etc. 4. The unit of surface has generally the same name as the linear unit ; thus, if the linear unit is one foot, the sur- face unit is one square foot, etc. 5. Some superficial units have no corresponding linear unit of the same name ; as, the rood and acre. 6. To refresh the memory,, we give a few of the more important measures of surfaces. 1 rood = 40 perches, or square rods. 1 acre = 4 roods. 1 square mile = 640 acres. Also, 1 chain = 100 links = 4 rods. 10 chains = 1 furlong. 1 square chain — 100 X 100 = 10 s 000 square links. 1 acre = 10 square chains = 100,000 square links. 175 176 MENSURATION. THE TRIANGLE. 7. The area is found by the following rules : Eule 1. — Multiply the base by one-half of the altitude) or, Eule 2. — Take half the sum of the sides, subtract from it each side separately, multiply the half sum and these remain- ders together, and take the square root of the product. 1. What is the area of a triangular field whose base is 40 rods and altitude 16 rods ? Ans. 2 acres. 2. Bequired the area of a triangle whose sides are 20, 30, and 40 chains respectively. Ans. 29 A. 8 P. 3. A man has a triangular garden whose sides are 150, 200, and 250 feet respectively ; required the area. Ans. 1666.66 yards. THE QUADRILATERAL. 8. Parallelogram. — The area is found as follows : Eule. — Multiply the base by tht altitude. 1. What is the area of a parallelogram 9 feet long and 7 feet wide ? Ans. 63 square feet. 2. How many acres in a square field whose side is 70£ chains ? Ans. 497 A. 4 P. 3. A man has a lot in the form of a rhombus, whose length is 333 feet and altitude 33.35 feet; required its area. Ans. 1233.95 square yards. 9. Trapezoid. — The area is found as follows : Eule. — Multiply one-half of the sum of the parallel sides by the altitude. 1. Eequired the area of a trapezoid, one side being 192 inches and the other 96 inches, and altitude 12 feet. Ans. 144 square feet. GEOMETRY. 177- 2. What is the area of a plank 24 feet long, 18 inches wide at one end and 12 inches at the other ? Ans. 30 square feet. 3. A farmer has a field in the form of a trapezoid, whose parallel sides are 95 and 75 rods respectively, and the per- pendicular distance between them 65 rods; how much land in the field ? Ana. 34 A. 2 E. 5 P. 10. Teapezium. — The area is found as follows : Rule. — Divide the trapezium into two triangles by a diago- nal, find the area of each triangle, and take their sum. 1. What is the area of a trapezium whose diagonal is 290 inches, and the altitudes of the triangles, the diagonal being the base, are 60 and 80- inches respectively ? Ans. 140 square feet, 140 square inches. 2. Required the area of a trapezium the lengths of whose sides are respectively 40, 60, 50, and 70 chains, and the diagonal 80 chains. Ans. 289 A. 1 R. 24 P. POLYGONS OP ANY NUMBER OF SIDES. 11. Regular Polygons. — The area is found as follows: Rule. — Multiply half the perimeter by the perpendicular let fall from the centre on one of the sides. 1. What is the area of a regular hexagon whose side is 14.6 feet and perpendicular 12.64 feet? Ans. 61.5147 square yards. 2. Required the area of an octagon whose sides are 9.941 feet and its perpendicular 12 feet. Ans. 477.168 square feet. 12. The following table shows the areas of ten regular polygons when the side is 1 : — 178 MENSURATION. Triangle 0.4330127 Square 1.0000000 Pentagon 1.7204774 Hexagon 2.5980762 Heptagon 3.6339124 Octagon 4.8284271 Nonagon 6.1818242 Decagon 7.6942088 Undecagon 9.3656404 Dodecagon 11.1961524 Now, since the areas of similar polygons are to each other as the squares of their homologous sides, to find the area of a regular polygon we have the following Eule. — Square the side of the polygon, and multiply by the tabular area set opposite the polygon. 3. What is the area of a regular hexagon whose side is 5 inches long ? Ans. 64.9519 square inches. 4. Eequired the area of an octagon whose sides are each 3 feet 4 inches. Ans. 53.649 square feet. 13. Irregular Polygon. — The area is found as follows : Rule. — Draw diagonals dividing the polygon into triangles, find the area of these triangles, and take the sum. 1. In the irregular pentagon ABCDE, the diagonal AG is 24 inches, the diagonal AD is 18 inches, the altitude of the triangle ABC is 8 inches, of ACD is 10 inches, and of AED 6 inches ; required the area. Ans. 240 square feet. 2. In the irregular hexagon ABCDEF, the side AB is 268, BG 249, CD 310, DE 290, EF199, and AF 24S links, and the diagonals AC 459, CE 524, and AE 326 links; required the area. Ans. 1 A. 2 E. 22 P. 13 yd. 47 ft. THE CIRCLE. 14. The circumference is found by the following Eule. — Multiply the diameter by 3.1416. Note. — Hence, the diameter equals the circumference divided by 8.1416, or multiplied by .31831. GEOMETRY. 179 1. What is the circumference of a circle whose diameter is 50 inches ? Ans. 157.08 inches. 2. A man has a circular fish-pond 32 rods in diameter ; what is the distance around it? Ans. 100.5312 rods. 3. Eequired the diameter of a water-wheel whose cir- cumference is 78.54 feet. Ans. 25 feet. 4. A man has a garden in the form of a circle, the dia. meter being 45 rods ; what is the distance around it ? Ans. 141.372 rods. 15. The length of an arc, when its degrees and radiun are given, is found as follows : Eule. — Multiply the number of degrees by the decimal .01745, and the product by the radiui. 1. The degrees in an arc are 45, and the radius 10; what is the length of the arc ? Ans. 7.852. 2. What is the length of an arc of 32° 38' 42", the radius being 25 inches? Ans. 14.2414 inches. 16. When the chord and chord of the half arc are given. Eule. — From 8 times the chord of half the arc, subtract tht shord of the whole arc, and divide the remainder by 3. 1. The chord of an arc is 96 inches, and the chord of half the arc is 60 inches ; what is the length of the arc ? Ans. 128 inches. 2. The chord of an arc is 16 inches, and the diametei of the circle is 20 inches; what is the length of the arc ? Ans. 18.5178 inehes. 17. The area of A circle is found .as follows : Eule I. — Multiply the circumference by one-fourth of the diameter, or the square of. the radius by 3.1416. Eule II. — Multiply the square of the diameter by .7854, or the square of the circumference by .07958. (Let the pupil prove the last rule from the previous principles.) 180 MENSURATION. 1. What is the area of a circle whose diameter is 50 inches and circumference 157.08 inches? Ans. 1963^ square inches. 2. Eequired the area of a circle whose diameter is 18 inches. Ans. 254.4696 square inches. 3. "What is the area of a circular garden whose circum ference is 90 rods ? Ans. 644.598 square rods. 18. The area op a sector is found as follows : Eule. — I. Multiply the arc by one-half the radius; or, II. The sector is to the circle as the number of degrees in the sector is to 360°- 1. What is the area of a circular sector whose arc con- ' tains 18°, the diameter of the circle being 6 feet ? Ans. 1.4137 square feet. 2. Eequired the area of a sector, the chord of half the arc being 30 inches, and the radius 50 inches. Ans. 1523.45 square inches. 19. The area or A segment is found as follows : Eule. — Find the area of the sector having the same arc, and also the area of the triangle formed by the chord of the segment and the radii of the sector. If the segment is greater than a semicircle, add the two areas ; if less, subtract them. 1. Eequired the area of a segment whose height is 2 inches, and chord 20 inches. Ans. 26.864 square inches. 2. What is the area of a segment whose height is 18 " inches, the diameter df the circle being 50 inches ? Ans. 632 sq. in. 3. Eequired the area of a segment whose arc is 1S0°, and radius of circle 12 feet. Ans. 226.1952 20. The area op A circular ring is foand as follows: GEOMETRY. 181 Btjle. — Find the difference of the squares of the radii, and multiply it by 3.1416. Demonstration. — Let the figure represent two circles having a com. mon centre 0; then the difference between them will be a circular ring. The area of circle OA is ■kOA\ and of OB is nOB 1 ; the difference is nOA* — n-OB* = k ( OA* — OB*), which proves the rule. 1. What is the area of the circular ring when the diameters are 20 and 30 ? Ans. 392.70. 2. A circular park 400 feet in diameter has a carriage- way around it 24 feet wide; required the area of the carriage-way. Ans. 3149.9776 square yards. 21. The side of an inscribed square is found thus : Eule. — Multiply the diameter by .7071, or multiply the cir- cumference by .2251. 1. What is the side of a square that can he cut out of a circular board whose diameter is 14 inches ? Ans. 9.899 inches. 2. How large a square can be cut out of a circular board whose circumference is 400 inches ? Ans. 90.04 inches. THE ELLIPSE. 22. An Ellipse is a plane figure bounded by a curve, the sum of the distances from every point of which to two fixed points is equal to the line drawn through those points and terminated by the curve. The two points are called foci; the line through the foci is the transverse axis; a line perpendicular to this through the centre is the conjugate axis. 16 182 MENSURATION. 23. The area is found by the follow- ing Rule. — Multiply half of the two axes ■& (— -* together, and multiply that product by 8.1416. 1. "What is the area of an ellipse whose transverse axis) is 20 inches and conjugate axis 16 inches? Ans. 251.328. 2. Required the area of an elliptical mirror whose length is 6 feet and breadth 5 feet. Ans. 23.562 square feet. MENSURATION OF VOLUMES. 24. Mensuration or Volumes is the process of deter- mining their surface and contents. 25. The Contents of a volume is the number of times it contains a given unit of measure. 26. The Unit or Measure of a volume is a smal 1 cube whose dimensions are known. MEASURES OP VOLUMES. 1 cubic foot = 1728 cubic inches. 1 " yard = 27 CI feet. 1 " rod = 4492^ fc feet. 1 wine gallon = 231 « inches. 1 ale gallon = 282 11 inches. 1 bushel = 2150.42 tc inches. 1 cord = 128 CC feet. GEOMETRY. 183 THE PRISM. 27. The convex surface or a right prism is found thus: Eule. — Multiply the perimeter of the base by the altitude. To find the entire surface, we add the bases. 1. What is the convex surface of a triangular prism, the three sides of whose base are respectively 6, 7, and 8 inches, and the height 50 inches ? Ans. 1050 square inches. 2. "What is the entire surface of a cube, the length of each side being 16 inches ? Ans, 10| square feet. 3. What is the entire surface of the triangular prism given in the first problem? Ans. .1090.66 square inches. 28. The contents oe. a prism are found thus : Eule. — Multiply the area of the base by the altitude of the prism. 1. Eequired the contents of a cube whose sides are 30 inches. Ans. 15.625 cubic feet. 2. Eequired the contents of a square prism whose alti- tude is 27 feet, and the side of the base 4 feet ? Ans. 432 cubic feet. 3. Eequired the contents of a triangular prism whose altitude is 24 feet, the sides of the base being 3, 4, and 5 feet respectively. Ans. 144 cubic feet. THE PYRAMID. 29. The convex, surface of a right pyramid is found f.hus : Eule. — Multiply the perimeter of the base by one-half the slant height. 1. What is the convex surface of a triangular pyramid whose sides are 3, 4, and 5 feet, and slant hefght 20 feet? Ans. 120 square feet. 184 MENSURATION. 2. Eequired the convex surface of a pentangular pyra- mid whose sides are each 5 feet, and slant height 60 feet. Ans. 750 square feet. 30. The contents or A pyramid are found thus : Eule. — Multiply the base by one-third of the altitude. 1. Eequired the contents of a pyramid whose base is a hexagon, each side being 5 feet, and whose altitude is 20 feet. Ans. 433.013; 2. The pyramid of Cheops is 480 feet high, and the base is a square 763.4 feet on a side ; required its solid contents. Ans. 93244729| cubic feet. THE CYLINDER. 31. The convex surface and contents are found thus : Eule 1. — The surface equals the circumference of the base multiplied by the altitude. Eule 2. — The contents equal the area of the base multiplied by the altitude. 1. What is the convex surface of a cylinder 12 feet loDg and 6 feet in diameter? Ans. 226.1952 square feet. 2. Eequired the convex surface of a cylinder whose length is 20 feet and the diameter of the base 8 feet. Ans. 502.656 square feet. 3. A man has a log 12 feet long and about 6f feet in diameter ; required its contents. Ans. 418.88 cubic feet. 4. The "Winchester bushel is a cylinder containing 2150.42 cubic inches, its height being 8 inches; what is its dia- meter? Ans. 18£ inches. THE CONE. 32. The convex surface and contents are found thus : Eule 1. — The surface equals the circumference of the base into one-half of the slant height. GEOMETRY. 185 -Rule 2. — The contents equal the area of the base into one* third of the altitude. 1. Find the convex surface and contents of a cone, the diameter of the base being 6 ft. and altitude 4 ft. Ans. Sur. = 47.124. 2. Find the surface and contents of a cone whose slant neight is 26 in. and radius of the base 10 in. Ans. Yol. = 2513.28. THE FRUSTUM OF A PYRAMID AND CONE." 33. The convex surface is found by the following Eule. — Find the sum of the perimeters or circumferences of the two bases, and multiply it by one-half of the slant height. 1. Eequired the convex surface of the frustum of a square pyramid whose slant height is 24 ft., the side of the 'lower base 12 ft., and of the upper base 8 ft. Ans. 960 sq. ft. 2. Eequired the surface of a frustum of a cone whose slant height is 20 ft., the diameter of the lower base being 12 ft., and of the upper base 8 ft. Ans. 628.32 sq. ft. 34. The contents of a frustum are found as follows : Etji.e. — Find the sum of the two bases and the square root of their product, and multiply this sum by one-third of the alti- tude of the frustum. Note. — In a frustum of a cone the following formula giveB a shorter rule :— V= f (R 1 + J- 2 + R . r) X *■ 3 1. "What is the amount of timber in a log which mea- sures 40 feet in length, the radius of one base being 6 feet and of the other 3 feet 1 Ans. 2638.944 cubic feet. 2. Eequired the contents of the. frustum of a regular hexagonal pyramid, the side of the greater end being 3 feet, that of the less 2 feet, the height being 24 feet. Ans. 394.9075 cubic feet. 16* 186 MENSURATION. 3. A cask, consisting of two equal conic frustums joined at their larger ends, has its bung diameter 30 inches, and its head diameter 20 inches; how many gallon of wipe will it hold if 3£ feet long ? Ans. 90.44 gallons. THE SPHERE. 35. The surface op a sphere is found as follows : Eule. — Multiply the diameter by the circumference; or, Square the radius, and multiply it by 4 and 3.1416. 1. Eequired the surface of a sphere whose diameter is 17 inches. Ans. 6.305 square feet. 2. How many square miles on the surface of the earth, the diameter being about 7-912 miles ? Ans. 196,663,355 square miles. 36. The surface of a zone is found as follows : Eule. — Multiply the height of a zone by the circumference of a great circle of the sphere. 1. The diameter of a sphere is 25 feet, and the height of the zone 6 feet ; what is the surface of the zone ? Ans. 471.24 square feet. 2. Eequired the surface of the torrid zone, the diameter of the earth being 7912 miles. Ans. 78,419,272 square miles. Note. — This is to be solved after the pupil has completed Trigonometry. 37. The contents of a sphere are found as follows : Eule. — Multiply the surface by one-third of the radius ; or, Multiply the cube of the diameter by \ of 3.1416. 1. Eequired the contents of a sphere whose diameter is 17 inches. Ans. 2572.4468 cubic inches. 2. Eequired the contents of the planet Mars, the diameter being about 4500 miles. Ans. 47713050000. GEOMETRY. 187 38. The contents of a spherical segment of one base are found thus : Rule. — Add the square of the height to three times the square of the radius of the base; multiply this sum by the height, and the product by .5236; or, see Th. X. B. VII. Note. — For the volume of a segment of two bases, see B. VII. Th. X. C. 4. 1. Required the contents of the segment of a sphere whose height is 4 inches, and radius of the base 8 inches. Ans. 435.635 cubic inches. 2. Find the volume of either temperate zone, the dia- meter of the earth being 7912 miles. Ans. 54,919,403,678 cubic miles. Note. — The pupil will solve this after completing Trigonometry. CYLINDRICAL RINGS. 39. A cylindrical ring is formed by bending a cylinder until the two ends meet. We find its surface by the fol- lowing , Etjle. — To the thickness of the ring add the inner diameter; multiply this sum by the thickness of the ring, and the product by 9.8696. Note. — For contents, multiply the sum by the square of \ the thickness, instead of the thickness, the other part of the rule being the same as for surface. 1. The thickness of a cylindrical ring is 4 inches, and the inner diameter 18 inches ; what is the convex surface ? Ans. 868.52 square inches. 2. The thickness of a cylindrical ring is 2 inches, and the inner diameter 1 foot ; required its contents. Ans. 138.1744 cubic inches. 188 MENSURATION. \ \ ,/\ / a \z\ 40. The side of an inscribed cube is found thus : Eule. — Multiply the diameter by .57736, or the radius by 1.15472. E . Demonstration. — Let the cube in the mar- gin represent an inscribed cube ; then will AE be the diameter of the sphere. Let the diameter be denoted by D, and the radius by R. Now, AE* or &* = AC 1 + TLB 2 ; but AC = AB* +UC 2 ; hence, D* = AB* + BC 1 -f~ CE 2 , or, since the sides are equal, _D*= 3AB*, or, D = AB X^ = ^X * 1.73205, and, consequently, AB = D X y.rtW = z) X -57736, or .45= B X 1-16472. 1. Eequired the side of a cube that can be cut out of a Bphere whose diameter is 16 inches. Ans. 9.23776. 2. Eequired the volume of a cube inscribed in a sphere whose circumference is 18.849552 inches. Ans. 41.571219 cubic inches. 41. The volume of an irregular body is found thus -. Eule. — Immerse the body in a vessel of known dimensions, containing water; note the rise in the water, and calculate accordingly. 1. A stone immersed in a cylindrical vessel 10 inches in diameter, raised the water 5 inches ; required the volume of the stone. Ans. 392.70. cubic inches. 2. A man put a stone into a vessel 14 cubic feet in capa- city, and it then required 2-1 quarts of water to fill the vessel ; required the volume of the stone. Ans. 13.9164 cubic feet. GEOMETRY'. 1§9 MISCELLANEOUS PROBLEMS — PLANE FIGURES. 1. How many yards of paper that is 30 inches wide will it require to cover the wall of a room 15J feet long, 11J feet wide, and 7f feet high ? Ans. 55.2833 yards. 2. A ladder 130 feet long, with its foot in the street, will reach on one side to" a window 78 feet high, and on the other to a window 50 feet high ; what was the width of the street ? Ans. 224 feet. 3. The diameter of a circle is 4 feet; required the area of the inscribed equilateral triangle. Ans. 3^3 square feet. 4. From a plank 16 inches broad, 6 square ft. are to be sawed off ; at what distance from the end must the line be struck 1 Ans. 4J feet. 5. The ball on the top of a church is 6 feet in diameter ; what did the gilding of it cost, at 8 cents per square inch ? Ans. $1302.884. 6. The area of an equilateral triangle, whose base falls on the dia- meter and its vertex in the middle of the are of a semicircle, is 100 square feet ; what is the diameter of the semicircle ? Ans. 26.32148. 7. The cost of paving a semicircular plot of ground, at 20 cents a square foot, amounted to $20 ; required its diameter. Ans. 15.9576. 8. A gentleman has a garden 80 feet long and 60 feet wide ; what must be the width of a walk extending around the garden, which shall occupy one-half of the ground 1 Ans. 10 feet. 9. Required the perimeter of a regular dodecagon which shall con tain the same area as a circle whose circumference is 1000 feet. Ans. 1011.67 feet. 10. If a horse tied to a post in the centre of a field by a rope 1 chain 78 links can graze upon an acre, what length of rope would allow it to graze upon 5$ acres ? Ans. 4 chains 15£ links. 11. A has a circular garden which is 20 rods, and B has a circular garden whose area is 6J times as great ; what is the diameter of B's garden? Ans. 50 rods. 12. A has a circular garden, and B a square one ; the distance around each is 64 rods ; which contains the most land, and how much ? Ans. 69.948 square rods. . 1 3. Atherton has a circular garden and Fell has a square one, and 190 MENSURATION. they contain 4 acres ; how much farther around is one than the other? Ans. 11.512 rods. 14. Mr. Thompson has a square yard containing ^ of an acre ; he makes a gravel walk around it which occupies £J of the whole yard ; what is the width of the walk ? Arts. 4 feet 1 J inches. 15. A general, attempting to draw up his division in the form of a square, found he lacked 100 men to complete the square ; he then re- ceived a reinforcement of five companies of 100 men each, and found he could increase the side of the square by 3 men and have 1 man remaining ; how many men had he at first ? Arts. 4125 men. VOLUMES. 1. The volume of a sphere is 606.132 cubic feet; required its diar meter. Ans. 10.5 feet. 2. The edge of a cube is 6 feet ; what is the volume of a sphere that may be inscribed within it ? Ans. 113.0976 cubic feet. 3. I have a cistern in the form of the frustum of a cone, its top dia- meter being 12 feet, its bottom diameter 9 feet, and its depth 5 feet ; how many barrels of water will it contain? Ans. 103.515 barrels. 4. Bunker Hill Monument is 220 feet high, 30 feet square at the base, and 15 feet at the vertex ; what is its volume ? Ans. 115500 cubic ft. 5. Mr. Wilson has a pond which covers 100 acres, the average depth being 10 feet ; how many cubic feet of water does it contain 1 Ans. 43560000 cubic feet. 6. A man has a log of wood 20 ft. long, the larger end being 3 ft. in dia- meter, and the smaller 2 ft. ; required the contents of the largest square stick, 20 ft. long, that can be sawed out of it. Ans. 63J cubic feet. 7. A bushel measure is 18£ inches in diameter and 8 inches deep ; what should be the dimensions of a measure of similar form to contain 64 bushels ? Ans. Diameter, 74 inches ; depth, 32 inches. 8. Mr. Benson can dig a shaft 5 feet each way in one day ; how long will it take him to dig a shaft 20 feet each way ? Ans. 64 days. 9. A man has a square garden 100 feet long, and wishes to make a gravel walk half-way around it ; what will be the width of the walk if >t takes up one-half of the garden ? Ans. 29.289 feet. GEOMETRY. 191 10. A wishes to enclose his garden, which is 100 feet long and 80 feet wide, with a ditch 4 feet wide ; how deep must it be dug that the soil taken out may raise the surface 1 foot ? Ans. 5.319 feet. 11. A cubic foot of brass is to be drawn into a wire fa of an inch in diameter ; required the length of the wire, supposing there is no loss of metal in the process. Arte. 31.252 miles. 12. Mr. Bonnycastle mentions a globe whose volume and surface are represented by the same number ; what was the diameter of this globe ? Ans. 6. 13. Mr. Haswell requires the weight of an iron shell 4 inches in dia- meter, the thickness of the metal being 1 inch, estimating a cubic inch of iron at \ of a pound. Ans. 7.3304 pounds. 14. Bunker Hill Monument is 220 feet high, the lower base being 30 feet square, the upper 15 feet square ; through its centre runs a cylin- drical opening 15 feet in diameter at the bottom and 11 feet at the top ; how many cubic feet of material in the monument ? Ans. 86068.444 cubio feet. 15. A gentleman has a bowling-green 300 feet long and 200 feet broad, which he wishes to raise 1 foot higher by means of the earth that is to be taken from a ditch that is to go around it ; to what depth must the ditch be dug, supposing its breadth to be 8 feet ? Ans. 7 feet 3.21 inches. 16. A man having a garden 100 feet long and 80 feet broad, wishes to make a gravel walk half-way around it ; what will be the width of the walk if it takes up one-half of the garden ? Ans. 25.9688 feet. 17. Three persons having bought a sugar loaf, want to divide it equally among them by sections parallel to the base; what is the altitude of each person's share, supposing the loaf is a cone 20 inches high ? Ans. 13.867 upper part ; 3.604 middle; 2.528 lower. Suggestion. — Solve it by the principle of similar cones being to each other as the cubes of their altitudes. Note. — Several of these problems are from the old writers on Mensuration. For more methods and exercises, see Bonhycastle's and Haswell's works on Mensuration. ELEMENTS OF TRIGONOMETRY. INTRODUCTION. LOGARITHMS. 1. Logarithms are a. species of numbers used to abbreviate Multiplication, Division, Involution, and Evolution. 2. The logarithm of a number is the exponent denoting the jpower to which a fixed number must be raised in order to produce the first number. 3. This fixed number is called the base of the system. The base of the common system is 10. 4. Eaising 10 to different powers, we have, 10° = 1 ; hence, is the log of 1 ; 10!= 10 " 1 " 10; 10 2 = 100 " 2 " 1'00; 10 3 =1000 " 3 " 1000; etc. 5. From this we have the following principles: Prin. 1. The logarithm of a number between 1 and 10 is between and 1, and is, therefore, a decimal. Prin. 2. The logarithm of a number between 10 and 100 is between 1 and 2, and is, therefore, 1 and a decimal. Thus, it has been found that the log. of 76 is 1.880814. Prin. 3. The logarithm of a number between 100 and 1000 is between 2 and 3, and is, therefore, 2 and a decimal. Thus, the log. of 458 is 2.660865. 6. When the logarithm consists of an integer and a decimal, 16 1 2 TRIGONOMETRY. the integer is called the characteristic, and the decimal part the mantissa. Thus, in 2.660865 the 2 is the characteristic, and .660865 is the mantissa. PROPERTIES OF LOGARITHMS. Prist. 1. — The characteristic is always one less than the number qf in- tegral places in the number. For, from Art. 4, we see that the log. of 100 is 2, the log. of 1000 is 3, and of any number between 100 and 1000 it is 2 and a decimal ; hence, the characteristic is one less than the number of integral places. ' Pkin. 2. — The logarithm qf the base is 1, and the logarithm qf 1 is zero. For, since 10 1 = 10, the log. of 10 is 1 ; and since 10° = 1, the logarithm of 1 is 0. Pein. 3. — The characteristic of the logarithm of a decimal is negative, and is numerically one greater than the number qf ciphers between the decimal point and the first significant figure. For, if we raise the base, 10, to powers which give decimals, we will have, 10° = 1 ; hence, log 1 = ; 10- ^.l " log.l = — 1; 10T Z =.01 " log .01 = — 2; 10- 8 =.001 " log .001 = — 3; etc. etc. which proves the principle. Thus, the log. of .458 is 1.660865. Prin. 4. — The logarithm of the product of two numbers is equal to the sum of the logarithms of those numbers. For, let M and N be any two numbers, and m and n their loga- rithms ; then we shall have, according to the definition, 10»> = M, 10" = JV. Multiplying these equations, member by member, we have, 10 m +"=ilf XiV". Ifence, log (M X N) = m + n; or, = log M-\- log N. INTRODUCTION. 3 Erin. 5. — The logarithm of the quotient of two numbers equals the dif- ference of the logarithms of those numbers. For, from the definition, we have, lO™ = M, 10" = N. Dividing the first by the second, we have, Hence, log ( — 1 = m — n, or, = log M — log N. Prin. 6. — The logarithm of any power of a number is equal to the logarithm of the number multiplied by the exponent of the power. For, since 10">=Jf, if we raise both members to the nth power, we have, 10 mn = M n . Hence, log M" = mn, or, = log M X n. Prin. 7. — The logarithm of the root of any number is equal to the logarithm of the number divided by the index of the root. For, since 10 m = M, if we take the nth root of both members, we have, • Hence", log y/W= -, or, log M-i- n. Prin. 8. — The logarithm of the product of any number multiplied by 10 is equal to the logarithm of the number increased by 1. Suppose log M = m; then, by Prin. 4, log (MX 10) = log M+ log 10. But log 10 = 1; Hence, log {MX 10) = m + 1- Thus, log (76 X 10) = 1.880814 + 1 ; or, log 760 = 2.880814. Prin. 9. — -The logarithm of the quotient of any number divided by 10 is equal to the logarithm of the number diminished by 1. 4 TRIGONOMETRY. Suppose log M=m; then, by Prin. 5, log (M h- 10) = log M— log 10; from which log(Jf-i-'lO)=m — 1. Thus, log (458 -s- 10) =2.660865 — 1; or, log 45.8 = 1.660865. 7. The following examples will' illustrate Principles 1, 3, 8, and 9. log 234 is 2.369216, log 23.4 " 1.369216, log 2.34 " 0.369216, log .234 " L369216, log .0234" 2.369216. From this, we see that when we change the place of the de- cimal point we change the characteristic, but do not change the decimal part of the logarithm. The minus sign is written over the characteristic, showing that it only is negative. TABLE OF LOGARITHMS. 8. A Table op Logarithms is a table by means of which we can find the logarithms of numbers, or the numbers corresponding to given logarithms. 9. In the annexed table the entire logarithms of the numbers up to 100 are given. For numbers greater than 100 the mantissa alone is given ; the characteristic being found by Prin. 1. 10. The numbers are placed in the column on the left, headed N ; their logarithms are opposite, on the same line. The first two figures of the mantissa are found in the first column of loga- rithms. 11. The column headed D shows the average differences of the ten logarithms in the same horizontal line. This difference is found by subtracting the logarithm in column 4 from that in column 5, and is very nearly the mean or average difference. INTRODUCTION. 5 TO FIND THE LOGARITHM OF ANY NUMBER. 12. To find the logarithm of a number o/one or two figures. Look on the first page of the table, in the column headed N, and opposite the given number will be found its logarithm. Thus, the logarithm of 25 is 1.397940, 87 is 1.939519. 13. To find the logarithm, of a number of thkee figures. Look in the table for the given number; opposite this, in column headed 0, will be found the decimal part of the loga- rithm, to which we prefix the characteristic 2, Prin. 1. Thus, the logarithm of 325 is 2.511883, 876 is 2.942504. 14. To find the logarithm of a number of Form figures. Find the three left-hand figures in the column headed N, and opposite to these, in the column headed by the fourth figure, will be found four figures of the logarithm, to which two figures from the column headed are to be prefixed. The character- istic is 3, Prin. 1. Thus, the logarithm of 3456 is 3.538574, " " 7438 is 3.871456. 15. In some of the columns, small dots are found in the place of figures : these dots mean zeros, and should be written zeros. If the four figures of the logarithm fall where zeros occur, or if, in passing back from the four figures found to the zero column, any of these dots are passed over, the two figures to be prefixed must be taken from the line just below. Thus, the logarithm of 1738 is 3.240050, 2638 is 3.421275. 16. To find the logarithm of a number of more than tow. figures. Place a decimal point after the fourth figure from the left hand, thus changing the number into an integer and a decimal. Find the mantissa of the entire part by the method just given. Then 16* 6 - TRIGONOMETRY. from the column headed D take the corresponding tabular differ- ence, multiply it by the decimal part, and add the product to the mantissa already found ; the result will be the mantissa of the given number. The characteristic is determined by Prin. 1. If the decimal part of the product exceeds .5, we add 1 to the entire part ; if less than .5, it is omitted. EXAMPLES. 1. Find the logarithm of 234567. Solution. — The characteristic is 5, Prin. 1. Placing a decimal point after the fourth figure from the left, we have 2345.67. The decimal part of the logarithm of 2345 is .370143 ; the number in column D is 185 ; and 185 X -67 = 123.95, and since .95 exceeds .5, we have 124, which, added to .370143, gives .370267 ; hence, log 234567 = 5.370267. 2. Find the logarithm of 4567. Ans. 3.659631. 3. Find the logarithm of 3586. Ans. 3.554610. 4. Find the logarithm of 11806. Ans. 4.072102. 5. Find the logarithm of .4729. Ans. 1.674769. 6. Find the logarithm of 29.337. Ans. 1.467416. 17. To find the number corresponding to a given logarithm. 1. Find the two left-hand figures of the mantissa in the column headed 0, and the other four, if possible, in the same or some other column, on the sanu line ; then, in column N, opposite to these latter figures, will be found the three left-hand figures, and at the top of the page the other figure of the required number. 2. When the exact mantissa is not given in the table, take out the four figures corresponding to the next less mantissa in the table ; sub- tract this mantissa from the given one; divide the remainder, with ciphers annexed, by the number in column D, and annex the quotient to the four figures already found. 3. Make the number thus obtained correspond with the cha- racteristic of the given logarithm, by pointing off decimals oi annexing ciphers. INTRODUCTION. 7 EXAMPLES. 1. Find the number whose logarithm is 5.370267. Solution.— The mantissa of the given logarithm is . . .370267 The mantissa of the next less logarithm of the table is . .370143 and its corresponding number is 2345. ■ I Their difference is 124 The tabular difference is 185 The quotient is . 185)124.00(.67 Hence, the required number is . 234567. Note. — If the characteristic had been 2, the number would have been 234.567; if it had been 7, the number would have been 23456700; if it had been 2, the number .would have been .0234567, etc. 2. Find the number whose logarithm is 3.659631. ■Ans. 4567. 3. Find the number whose logarithm is 2.554610. Ans. 358.6. 4. Find the number whose logarithm is 1.072102. Ans. 11.806. 5. Find the number whose logarithm is 2.674769. Ans. .04729. 6. Find the number whose logarithm is 3.065463. Ans. .0011627. MULTIPLICATION BY LOGARITHMS. 18. From Prin. 4, for the multiplication of numbers by means of logarithms, we have the following Eule. — Find the logarithms of the factors, take their sum, and find the number corresponding to the result; this number will be the required product. Note. — The term sum is used in its algebraic sense. Hence, when any of the characteristics are negative, — the mantissa is always positive, — we take the difference between the sums of the positive and negative characteristics, and prefix to it the sign of the greater. If any thing is to be carried from the addition of the mantissas, it must be added to a positive characteristic, or subtracted from a negative one. 8 ' TRIGONOMETRY. EXAMPLES. 1. Multiply 35.16 by 8.15. Solution. log 35.16 = 1.546049 log 8.15 = 0.911158 2.457207 457125 Product, 286.554 152)82.00(.54 2. Find the product of .7856, 31.42. Ans. 24.6835, 3. Find the product of 31.42, 56.13, and 516.78. Ans. 911393.7. 4. Find the product of 31.462, .05673, and .006785. Ans. 01211168. 5. Product of .06517, 2.16725, .000317, and 42.1234 Ans. .001886. 6. Product of 2.3456, .00314, 123.789, .00078, and 67.105. Ans. .04772076. DIVISION BY LOGARITHMS. 19. From Prin. 5, t6 divide by means of logarithms, we have the following Rule. — Find the logarithms of the dividend and divisor, subtract the latter from the former, and find the number corresponding to the result ; this number will be the required quotient. Note. — The term subtract is here used in its algebraic sense ; hence, we must subtract according to the principles of algebra. 1. Divide 783.5 by 6.25. EXAMPLES. Solution. log 783.5 = 2.894039 log 6.25 = 0.795880 2.098159 o nA+.id»Ti+. V. >fi Sfi .097951 346)208(6 INTRODUCTION. 9 2. Divide 272.636 by 6.37. Ans. 42.8. 3. Divide 50.38218 by 67.8. Ans. .7431. 4. Divide 155 by .0625. Ans. 2480. ARITHMETICAL COMPLEMENT. 20. The operation of division when combined with multipli- cation is somewhat simplified by using the principle of the arith- metical complement. 21. The Arithmetical Complement of a logarithm is the result arising from subtracting the logarithm from 10. Thus, the arith- metical complement of the logarithm 5.623427 is 10 — 5.623427, or 4.376573. 22. The arithmetical complement may be written directly from the table, by subtracting each figure of the logarithm from 9, except the right-hand figure, which must be taken from 10. This is the same as subtracting the logarithm from 10. . 23. We will now prove that the difference between two logarithms is equal to the first logarithm, plus the arithmetical complement of the second, minus 10. Let a = the first logarithm, b = the second logarithm, and c = 10 — b = arith. comp. of b. The difference is a — b. But, — b = c — 10. Hence, a — b = a + c — 10, which proves the principle. 24. Hence, to divide by means of the arithmetical complement, we have the following Rule. — Add the arithmetical complement of the logarithm of the divisor to the logarithm of the dividend, subtract 10, and find the -number corre- sponding to the difference, this number will be the required quotient. EXAMPLES. 1. Divide 856.3 by 45.32. 10 TKIGONOMETK5T. Solution. log 856.3 2.932626 (a. o.) log 45.32 8.343710 Quotient, 18.8945 1.276336 2. Divide 0.3156 by 78.35. log 0.3156 . . 1.499137 (a. c.) log 78.35 . 8.105961 Quotient, .004028 £605098 3. Divide 3.7521 by 18.346. Ans. .204519. 4. Divide 483.72 by .30751. Ans. 1573.02. 5. Multiply 32.16 by 7.856, and divide the product by 45.327. Ans. 5.574. 6. Divide the product of 31.57 and 123.4 by the product of 316.2 and .0316. Ans. 389.8884. 7. Find by logarithms the first term of the proportion, x : 73.15 : : 48.16 : 3167. Ans. 1.11237. INVOLUTION BY LOGARITHMS. 25. From Prin. 6, to raise a number to any power, we have the following Kule. — Find the logarithm of the number, multiply it by the exponent of the power, and find the number corresponding to the result. EXAMPLES. 1. Find the 4th power of 45. Solution. log 45 = 1.653213 4 Power, 4100625 6.612852 2. Find the cube of 0.65. Ans. 0.2746. 3. Find the 6th power of 1.037. Ans. 1.243. 4. Find the 7th power of .4797. Ans. 0.005846. INTRODUCTION. 11 EVOLUTION BY LOGARITHMS. 26. From Prin. 7, to extract any root of a number, we have the following Rule. — I. Find the logarithm of the number, divide it by the index of the root, and find the number corresponding to the result. II. If the characteristic is negative and not divisible by the index of the root, add to it the smallest negative number that will make it divisible, prefixing the same number with a plus sign to the mantissa. EXAMPLES. 1. Find the square root of 576. Solution. log 576 = 2.760422 2.760422-^2=1.380211 Hence, the root is 24. 2. Find the fourth root of .325. Solution. log .325 = 1.511883 = 1 + 3.511883. Then (I + 3.511883) -s- 4 = 1.877971 Hence, the quotient is,. .75504. 3. Find the fifth root of .0625. Ans. .574348. 4. Find the cube root of 7. . Ans. 1.9129. 5. Find the fifth root of 5. Ans. 1.3797. 6. Find the tenth root of 8764.5. Ans. 2.479. CALCULATION OF LOGARITHMS. The pupil will by this time naturally inquire how these logarithms are calculated. This we have not room to explain here ; in fact, an explanation of the modern methods would be almost too difficult for the majority of pupils who study this book. Only a general idea can here be given. In computing logarithms, it is only necessary to calculate the loga- rithms of prime numbers, since the logarithms of composite numbers may be obtained by adding the logarithms of their prime factors. The logarithms of the prime numbers were first computed by com- 12 TRIGONOMETRY. paring the geometrical and arithmetical series, 1, 10, 100, etc., and 0, 1, 2, etc., and finding, geometrical and arithmetical means ; the arithmetical mean being the logarithm of the corresponding geome- trical mean. This method was exceedingly laborious, involving so many multiplications and extractions of roots. The method now generally used is that of series, by which the com- putations are much more easily made. The following formula is de- rived by algebraic reasoning. ■ log (1 + ,) = A (f _|+| 3 _|V|-etc.) In this the quantity A is called the modulus, which in the Napierian system is unity. The series, when A is one, put in a more convenient form, becomes, •etc. log. (. + 1) - log. , = 2 ( ir _L_ + w ± fW + gfarpijr From which, knowing the logarithm of any number, we readily find the logarithm of the next larger number. The pupil will be interested in finding logarithms by this formula. Begin with 2, in which 2 = 1. The logarithm found will be the Napierian logarithm, and this mul- tiplied by 0.434294 will give the common logarithm. PLANE TRIGONOMETRY. DEFINITIONS AND PRIMARY PRINCIPLES. 1. Plane Trigonometry is the science which treats of tha solution of plane triangles. 2. The Solution of a triangle is the operation of finding the unknown partsTvhen a sufficient number of the known parts are given. 3. In every triangle there are six parts ; three sides and three angles. These parts are so related that when three of the parts are given, one being a side, the other parts may be found. 4. An angle is measured, as we have previously seen, by the arc included between its sides, the centre of the circumference being at the vertex of the angle. 5. For measuring angles, as has already been explained, the circumference is divided into 360 equal parts, called degrees; each degree into 60 equal parts, called minutes, etc. 6. AQuADRANTis one-fourth of the circumference of a circle; hence, if two lines be drawn through the centre of a circle at right angles to each other, they will divide the circumference into four quadrants. Each quadrant con- tains 90°. 7. The Complement of an arc is 90° minus the arc ; thus, DC is the complement of BC ; also, the angle DOOis the comple- ment of BOO. 8. The Supplement of an arc is 180° minus the arc; thus, 17 13 14 PLANE TRIGONOMETRY. AE is the supplement of the arc BDE; also, the angle AOE is the supplement of the angle BOE. 9. In Trigonometry, instead of comparing the angles of tri- angles, or the arcs which measure them, we compare certain lines, called functions of the arcs. A function of a quantity is something depending upon the quantity for its value. These functions are the sine, cosine, tangent, cotangent, secant, and cosecant. 10. Thus, instead of reasoning with the angle ACB, or the arc AB, which measures it, we draw the per- pendicular AD, and use the lines AD and ■ CD. The line AD is called the sine of the arc or angle; the line CD is called the cosine of the arc or angle. 11. If we draw BE perpendicular to CB, meeting CA produced in E, the line BE is called the tangent of the angle, and the line - CE is called the secant. 12. In comparing the sides and angles, these lines, we say, are used instead of the i angles or the arcs. The necessity for such lines is evident, since we could not compare the sides, which are straight lines, with the angles, or the curve lines, which measure them; We will now represent these lines in the first and second quadrants. 13. The Sine of an arc is the per- pendicular let fall from one extremity -of the arc on the diameter which passes through the other extremity. Thus, CD is the sine of the arc AC. 14. The Cosine of an arc is the sine of its complement ; or it is the distance between the foot of the sine and the centre of the circle ; thus, CE or OD is the cosine of the arc A C. PLANE TRIGONOMETRY. 15 15. The Tangent ofan arc is a line which is perpendicular to the radius at one extremity of the arc, and limited by a line passing through the centre of the circle and the other extremity; thus, AT is the tangent of AC. 16. The Cotangent of an arc is equal to the tangent of the complement of the arc ; thus, BT' is the cotangent of AC. 17. The Secant of an arc is a line drawn from the centre of the circle through one extremity of the arc, and limited by a tangent at the other extremity ; thus, OT is the secant of AC. 18. The Cosecant of an arc is the secant of the complement of the arc; thus, OT' is the cosecant of AC. 19. The sine, cosine, tangent, cotangent, etc. of an arc are in- dicated as follows : sin A C; tan A C; sec A C; cos A C; cot A C; cosec A C. 20. Principles. — From the definitions now given, we can readily derive the following simple principles. 1. The sine of an arc equals the sine of its supplement, and also the cosine of an arc equals the cosine of its supplement. Dem.— Take the arc ABF; its sine is FG, its supplement is FH, and the sine of its supplement is FG. Hence, its sine equals the sine of its supplement. Jts cosine is GO, which is also the cosine of FH. Hence, etc. 2. The tangent and cotangent of an arc are respectively equal to the tangent and cotangent of the supplement of the arc. Dem.— The tangent of the arc ABF is AT'", and the tangent of its supplement FH is HT", and, by similar triangles, it may be shown that AT'" equals HT" ; therefore, etc. 3. The secant and cosecant of an arc are respectively equal to the secant and cosecant of the supplement of the arc. This may be demonstrated in a manner quite similar to those above. Let the pupil be required to show it. 4. If a equals any arc or angle, then we shall have, from the definitions, 16 PLANE TRIGONOMETRY sin a = cos (90° — a) tan a = cot (90° — a) sec a = cosec (90° — a) NATURAL SINES, COSINES, ETC. 21. The length of these trigonometrical lines may be expressed in numbers, differing, of course, as the radius of the circle is lai'ger or smaller. If the radius is regarded as unity, or 1, we have what are called natural sines, cosines, etc. The method of calculating these sines, cosines, etc. will be explained hereafter. The operation of multiplying and dividing by these natural sines being long and tedious, it has been found more convenient to use logarithmic sines, which we will now explain. TABLE OP LOGARITHMIC SINES. 22. A Logarithmic Sine, Cosine, Tangent, or Cotangent is' the logarithm of the sine, cosine, tangent, or cotangent of an arc of a circle whose radius is 10,000,000,000. 23. A Table of Logarithmic Sines is a table containing the logarithmic sine, cosine, tangent, and cotangent of arcs. 24. The table of logarithmic sines may be calculated from a table of natural sines, as will be explained hereafter. In the table, the degrees are given at the top and bottom of the page, and the minutes at the sides, in the column headed M. 25. The column headed D contains the increase or decrease for 1 second. This is found by subtracting the logarithmic sine, etc. of an arc from that next exceeding it by 1 minute, and dividing the difference by 60. 26. To find the logarithmic sines, cosines, etc. of arcs or angles. 1. When the arc is expressed in degrees, or in degrees and minutes. If the angle is less than 45°, look for the degrees at the top of the page, and for the minutes in the &/i!-hand column ; then, opposite to the minutes, on the same horizontal line, in the column headed PLANE TRIGONOMETRY. 17 Sine, will be found the logarithmic sine ; in that headed Cosine will be found the logarithmic cosine, etc. Thus, log sin 23° 35' log tan 23° 35' 9.602150 9.640027 If the angle exceeds 45°, look for the degrees at the bottom of the page, and for the minutes in the right-hand column ; then, oppo- site to the minutes, in the same horizontal line, in the column marked at the bottom Sine, will be found the logarithmic sine, etc. Thus, log cos 65° 24' 9.619386 log tan 65° 24' 10.339290 2. When the arc contains seconds. — Find the logarithmic sine, etc. as before; then multiply the corresponding number found in column D by the number of seconds, and add the product to the preceding logarithm for the sines or tangents, and subtract it for cosines or cotangents. "We subtract for cosine and cotangent, because the greater the arc the less the cosine or cotangent. In multiplying the tabular difference by the number of seconds, we observe the same rule for the decimal point as in logarithms. If the arc is greater tlmn 90°, we find the sine, cosine, etc. of its supplement. EXAMPLES. 1. Find the logarithmic sine of 36° 24' 42". log sin 36° 24', Tabular difference, No. of seconds, Product, log sin 36° 24' 42", 2. Find the logarithmic cosine of 64° 30' 30". 17* 2.85 42 119.70 to be added, 9.773361 120 9.773481 L8 PLANE TRIGONOMETRY. 4.41 30 log cos 64° 30', • Tabular difference, No. of seconds, Product, log cos 64° 30' 30", 3. Find the logarithmic tangent of 120° 15' 24". 9.633984 132.30 to be subtracted, 132 9.633852 The given arc, sqL ice, 4.84 36 24", thmic sine UTION. 180° 00' 00" 120 15 24 Supplement, log tan 59° 44', Tabular differer No. of seconds, 59 44 36 to be added, of 40° 40' 40". 10.233905 174.24 log tan 120° 15' Find the logari 10.334079 Ans. 9.814117. 5. Find the logarithmic cosine of 140° 30' 20". 'Ans. 9.887441. 6. Find the logarithmic tangent of 85° 25' 45". Ans. 11.097200. 7. Find the logarithmic cotangent of 144° 44' 28". Ana. 10.150603. 27. To find the arc corresponding to any logarithmic sine, cosine, tangent, or cotangent. 1. Look in the proper column of the table for the given loga- rithm ; if found there, and the name of the function be at the head of the column, take the degrees at the top, and the minutes on the left; but if the name of the function is at the fool of the column, take the degrees at the bottom, and the minutes on the right. t 2. If the given logarithm is not exactly given in the table, PLANE TRIGONOMETRY. 19 chen take the next less logarithm, subtract it from the given logarithm, and divide the remainder by the corresponding tabular difference ; the quotient will be seconds, which must be added to the degrees and minutes corresponding to the logarithm taken from the table, for sines and tangents, and subtracted for cosines and cotangents. EXAMPLES. 1. Find the arc whose logarithmic sine is 9.617033. SOLUTION. Given log sine, 9.617033 Next less in table, 9.616894 Tabular difference, 4.63) 139.00(30, to be added. Hence, the arc or angle is 24° 27' 30"- 2. Find the arc whose logarithmic cosine is 9.704682. SOLUTION. Given log cosine, 9.704682 Next less in table, 9.704610 Tabular difference, 3.58) 72.00(20, to be subtracted. Hence, the arc or angle is 59° 33' 40"- 3. Find the arc whose logarithmic sine is 9.438672. Ans. 15° 56' 14". 4. Find the arc whose logarithmic cosine is 9.634520. Ans. 64° 27' 47". 5. Find the arc whose logarithmic tangent is 10.753246. Ans. 79° 59' 24". 6. Find the arc whose logarithmic cotangent is 11.449852. Ans. 2° V 40"- 28. Having learned how to find logarithmic sines, cosines, etc., we will next demonstrate some theorems for the solution of tri- angles. 20 PLANE TRIGONOMETRY. THE THEOREMS OF TRIGONOMETRY. 29. The Theorems of Trigonometry express the relation between the sides and trigonometrical functions of the angles of triangles, 30. We give five theorems, the first three relating to triangles in general, the others to right-angled triangles. THEOREM I. 31. In any plane triangle, the sides are proportional to the sines of thi opposite angles. Let ABC be a plane triangle ; then will CB:C4::sin4:sin.B. For, with A as a centre, and a radius AE equal to BC, describe the arc EG, and draw the perpendicular EF. With B as a cen tre, and the equal radius BC, describe the arc CH, and draw the per- pendicular CD; then will CD be the sine of the angle i?, and EF be the sine of the angle A, to the same radius. Now, by similar triangles (B. III. Th. X.), AE : AC : : EF : CD. BvAAE equals CB, EF is sin A, and CD is sin B. Hence, BC : AC: :sin-4 : sin B. In a similar manner, it may be shown that ^lC:AB::sin.B::sin C. Therefore, etc. THEOREM II. 32. In any plane triangle, the sum of any two sides is to their difference an the tangent of half the sum of the opposite angles is to the tangent of half their difference. Let ABC be any plane angle ; then will BC + A C : BC — A C : : tan £ (A + B) : tan £ (A — B). PLANE TRIGONOMETRY For, produce AC to D, making CD equal to CB, and draw BD; take CE equal to AC, dx&vrAE, and produce it toF; then AD is the sum and BE the difference of the two sides A C and £C. The sum of the angles CAE and AEC equals the sum of CAB and C.RA, both sums being equal to 180° minus ACB (B. I. Th. XIII.); but the angle CAE equals AEC (B. I. Th. X.) ; hence, CAE or CAF is the half sum of CAB and CRA; also, BAF is, the Aa^ difference of the angles C4-B and ABC; since it equals the half sum CAE, subtracted from the greater angle CAB* The angle CDF equals CBD, since CB equals CD; also, C4.E. which equals AEC, is equal to the vertical angle FEB; hence, the third angles of the triangles, AFD and EFB, are equal, and, therefore, AFis perpendicular to BD; consequently, if then we regard AF as, the radius, FD will be the tangent of DAF, and FB will be the tangent of FAB. Now, by similar triangles, AD:EB::FD:FB; or, CB + AC-.CB — AC:: tan i (A + B): tan i(A — B). THEOREM III. 33.' In any plane triangle, if a line is drawn from the vertical angle per- pendicular to the base, then the whole base will be to the sum of the other two sides as the difference of those sides is to the difference of the segments of the base. Let ABC be a triangle, and CD perpendicular to the base ; then will AB:AC + BC::AC — BC-.AD — DB. * This principle is thus proven : — Let a and 6 be any two quantities ; then the half sum Js — - — , and the half difference is — - — ; and minus the half mm equals the half difference. — i— t and tk e half difference is — - — ; and a — = — ^— ; that ii, the greater 22 PLANE TRIGONOMETRY. For, from Th. VI. Book III., AC 2 = lD 2 +l)C : ', and ~BC 2 4= ~RD* + T)C 2 . Subtracting, Zc* — £C 2 = 'A& — ~BD\ Hence (B. III. Th. V. C. 2), {AC+ BC) X(iC- BO) = [AD+BD) X (AD— BD) • therefore, AD + DB: AC+BC : : AC—BC : AD—DB. Therefore, etc. THEOREM IV. 34. In any right-angled plane triangle, radius is to the sine of either angle as the hypothenuse is to the side opposite. Let C-4-Bbe a triangle right-angled at A, and denote the radius by It : then will M : sin C-.-.CB: AB. For, from the point O as a centre and any radius, as CE, describe the arc EF, and draw ED perpendicular to CA ; then will ED be the sine of the angle C. The two triangles CED and CAB are similar; hence, we have (B. III. Th. X.), CE : ED : : CB : BA, or, B : sin C : : CB : BA. Therefore, etc. Cor. It may also be shown that radius is to the cosine of either acute ingle as the hypothenuse is to the side adjacent. THEOREM V. 35. In any right-angled plane triangle, radius is to the tangent of either acute angle as the side adjacent is to the side opposite. Let CAB be a triangle right-angled at A; then will R : tan C : : CA : AB. For, with C as a centre and any radius CD, describe the aro PLANE TRIGONOMETRY. 23 DE, and draw DF perpendicular to CA; FD will be the tangent of the angle C. The triangles CDF and CAB are similar ; hence, CD : DF-.-.CA: AB, or, S : tan C : : CA : AB. Therefore, etc. Cor. It may also be shown that radius is to cotangent of either angle, as side opposite is to side adjacent. SOLUTION OF TRIANGLES. 36. The Solution, of a Triangle is the process of finding the anknown parts when a sufficient number of the parts are given. 37. There are six parts in a plane triangle, and three of these — one of the three being a side — must be given to find the other parts. 38. If the angles alone were given, it is clear that the sides could not be determined, since there could be an indefinite number of triangles having their angles respectively equal. 39. There are four cases, as follows : i 1. -When two angles and a side are given. 2. When two sides and an angle are given. 3. When two sides and the included angle are given. 4. When the three sides are given. CASE I. 40. Given two angles and one side, to find the remaining parts. Method. — We subtract the sum of the - given angles from 180° to find the third angle, and then find the sides by Theorem I. EXAMPLES. 1. In a triangle ABC, there are given the angle A — 32° 24', the angle B — 40° 32', and the side AB = 240 ; required the other parts. 24 PLANE TRIGONOMETRY. Solution. — Let AB C represent the triangle; then the sum of A and B = 72° 56', and C= 180° — 72° 56' = 107° 04'. Then, to find 4 C, we have, AC : AB:: sin B : sin C. Hence, 4C = ABX sin.B-=-sin C. From which .4 C is readily found by multi- plying 240 by the natural sine of B, and dividing by the natural sine of C. It is simpler, however, to use logarithms. To find AC, we add the log of AB and log sin B, and subtract log sin C, or add the arith. comp. of log sin C. a. c. log sin C (107° 04'), 0.019558 log sin B (40° 32'), 9.812840 log AB (240), 2.380211 log^C, 2.212609 . -.4(7=163.158 To find the side BC, we have, BC-.AB:: sin A : sin C: or, by logarithms, a. clog sin C (107° 04'), 0.019558 log sin A (32° 24'), 9.729024 iog AB (240), 2.380211 log -BC, 2.128793 . :BC = 134.522 2. In the triangle ABC, there are given the angle A = 27° 40', the angle C= 65° 45', and the side AB = 625, to find the other parts. . Am. B = 86° 35' ; BC = 318.29 ; AC = 684.266. CASE II. 41. Given two sides and an angle opposite one of them, to find the remaining parts. Method. — One of the required angles is found by Theorem I. The third angle is found by subtracting the sum of the two from 180° ; the third side is found by Case I. PLANE TRIGONOMETRY. 25 EXAMPLES. 1. In the triangle ABC, there are given AC = 200, CB=150, and the angle A = 44° 26', to find, the other parts. Solution. — Let ABC be a triangle in which c A = 44° 26', 4C = 200, and 50 = 150 ; then, to find the angle B, we have, sin .B : sin ;!:: .4 C:.BC, or, BC (150) a. c. 7.823009 : AC (200) ■ 2.301030 i: sin4 (44° 26 r ) 9.845147 : sinB ( ) 9.969186 .-. B = 68° 40' 16", or, 111° 19' 44" In this problem, if the side BC, opposite the given angle .4, Is shorter than>the other given side AC, the solution will be am- biguous; for two triangles, ACB and ACB', may be formed, each of which will satisfy the conditions of the problem. Hence, the angle B found above may be either ABC or B'. But these, it will . be seen, are supplements of each other; hence, in finding the angle corresponding to sin B, we take the angle or its supplement. In practice, there is often some circumstance to determine whether the angle is acute or obtuse. If the angle given is obtuse, the other angles must be acute, and there will be but one solu- tion. If the side BC is equal to or greater than AC, there will be but one triangle. In the given diagram above, the angle ABC= 111° 19' 44", and AB'C= 68° 40' 16"; hence, the angle ACB = C 2A° 13' 16", and the angle ACB' = 113° 6' 16". To find the side AB, we have, AB-.CB:: sin ACB : sin A; from which, by logarithms, we find AB = 88.085. To find the side AB', we have, AB'-.CB':: sin A CB' : sin A ; from which, by logarithms, we find AB' = 197.484. is 26 PLANE -TRIGONOMETRY. 2. In a triangle ABC there are given AB 45.96, BC 62.50, and the angle A 79° 21'; find the remaining parts. Ans. C = 46° W 38" ; B = 54° 22' 22" ; AC = 51.69. (There is no ambiguity, since the side _SC is greater than^C.) 3. In a. triangle ^JJCthere are given BC= 15.71, AC= 21.12. and the angle A = 27° 50' ; find the other parts. Ans. C= 113° 17' 13"; 5= 38° 52' 47"; AB= 30.906. or, C= 11° 2' 47"; -B= 141° 7' 13"; ^-B= 6.447. CASE III. 42. Given two sides and the included angle, to find the remaining parts. Method. — We find the sum of the two angles by subtracting the given angle from 180°, and divide this by 2 for the half sum. We then find the half difference, by Theorem II. Having found the half sum and half difference of the two angles, we find the greater angle by adding the half difference to the'half sum ; and the less by subtracting the half difference from the half sum. The third side is found by Theorem I. EXAMPLES. 1. In the triangle ABO, let BG= 680, AC= 460, and the in eluded angle 84° ; required the other parts. Solution. — Let ABO represent the triangle, .4C=460, BC= 680, and the angle C = 84°. Then, AC+ 50=460 + 680= 1140; BC—AC= 680 — 460 =220. A + B = 180° — 84° = 96°; hence, half sum = 48°. The half dif- ference we find by the following proportion. BO+AG 1140 ar. co. 6.943095 : BC—AO 220 . . 2.342423 : : tan J (A + B) 48° . . 10.045563 : tanj (A — B) 12° 5' 49" 9.331081 Hence, A = 60° 5' 49" ; and B = 35° 54' 11' The other side, found by Theorem I., equals 783.733. PLANE TRIGONOMETRY. 27 2. Given two sides of a plane triangle 240 and 360, and the included angle 68° 36' ; required the other parts. Ans. 72° 02' 26 ; 39° 21' 34"; 352.349. CASE IV. 43. Given the three sides of a plane triangle, to find the angles. Method. — Let fall a perpendicular upon the greater side from the angle opposite, dividing the triangle into two right-angled triangles. Find the difference of the segments of the base by- Theorem III. ; half this difference added to half the base gives the greater segment, and subtracted from half the base gives the less. We will then have two sides and the right angle of two right-angled triangles, from which we can find the acute angles /by Theorem I. EXAMPLES. 1. In a triangle ABC, given AB = 60, .4(7=50, and BC= 40, to find the angles. Solution. — Let ABC represent the tri- angle; then AB = m, AC— 50, BC = 40; then, by Th. III., AB : AC + BC: : AC— BC: AD — BD, or, 60: 90 :: 10 .AD — BD. hence, AD — BD= 90 X 10-4- 60 = 15; then, XD = i(60+15) = 37.5 and BD = i(60 — 15) =22.5 Then, in the triangle ACD, to find the angle ACD, a. o. AC (50) 8.301030 AD (37.5) : sin D (90°) sin A CD 48° 35' 25" 1.574031 10.000000 9.875061 28 PLANE TRIGONOMETRY. Then, in the triangle BCD, to find the angle BCD, ■ a. c. BC (40) 8.397940 : BD (22.5) 1.352183 ::sinD (90°) 10.000000 : sin BCD 34° 13' 44" 9.750123 ■ Hence, A = 90° — 48° 35' 25" = 41° 24' 35", and .B = 90° — 34° 13' 44" = 55° 46' 16", and C = 48° 35' 25" + 34° 13' 44" = 82° 49' 09". 2. In a plane triangle the sides are 1005, 1210, and 1368 ; re- quired the angles. Ana. 45° 22' 35"; 58° 58' 18"; 75° 39' 7". SOLUTION OF RIGHT-ANGLED TRIANGLES. 44. In the solution of right-angled triangles we have the four following cases: 1. When the hypothenuse and an acute angle are given. 2. When the hypothenuse and a side are given. 3. When one side and the angles are given. 4. When the two sides about the right angle are given. Method. — The first three cases are readily solved by Theorem ... ; remembering that the sine of 90° is radius, the log. sin. being 10. The fourth case may be solved by Theorem V. ; or we may find the hypothenuse by B. III. Th. VI., and then find the angles by Theorem I. These four cases may also be solved by Theorems IV. and V. ; but the method suggested above is preferred, since it is simpler and more easily remembered. EXAMPLES. 1. In a right-angled triangle, given the hypothenuse 475 and the angle at the base 36° 34' ; find the other parts. PLANE TRIGONOMETRY. 29 Solution. —Let CAB represent the triangle, BC being equal to 475 and the angle C = 36° 34' ; then, to find AB, we have, sin A 90° a. c. 0.000000 : sin C 36° 34' 9.775070 : : CB 475 2.676694 : AB 282.985 2.451764 The angle B = 90° — (36° 34') = 53° 26 ; then, by a similar proportion, we can find the side CA = 381.503. 2. Given the hypothenuse 45.36 and the angle at the base 45° 36' ; required the other parts. Ans. 3. Given the hypothenuse 396 and the base 218, to find the other parts. - Ans. 330.59; 33° 24' 05"; 56° 35' 55". 4. Given the two sides 58.75 and 74.58, to find the remaining parts. Ans. 94.94; 38° 13' 45"; 51° 46 / 15". PRACTICAL APPLICATIONS. HEIGHTS AND DISTANCES. 45. A Horizontal Plank is one which is parallel to the plane of the horizon. ''46. AVertical Plane is one which is perpendicular to a horizontal plane. 47. A Horizontal Line is any line in a horizontal plane. A vertical line is a line perpendicular to a horizontal plane. -" 48. A Horizontal Angle is an angle in a horizontal plane. 49. A Vertical AHGLiis ar* angle in a vertical plane. 50. An Angle op Elevation is a vertical angle having one 18* 30 PLANE TRIGONOMETRY. c V 4 side horizontal, and the inclined side above the horizontal side ; as BAD. 51. An Angle of Depression is a ver- tical angle having one side horizontal, and the inclined side under the horizontal side; as CDA. 52. Distances upon the ground are usually measured by a chain, called Gunter's Chain. Dr 66 feet long, and consists of 100 links chain is used, consisting of 50 links. 53. Angles are measured by various instruments. Horizontal angles are measured by an instrument called The Compass. Hori- zontal and vertical angles are both measured by the Theodolite, or, what is still better for general use, a Transit-Theodolite. This chain is 4 rods Sometimes a half CASE I. • 54. To determine the height of a vertical object standing upon a hori- zontal plane. Method. — Measure from the foot of the a object any convenient horizontal distance AB; at the point A take the angle of ele- vation BAC; then, in the triangle ABC we have a side and an acute angle ; hence, we can readily find the altitude. 1. From the foot of a tower I measure a horizontal line 120 feet, and at its extremity find the angle of elevation to be 48°. 36'; what was the height of the tower ? Ans. 136.113 feet. CASE II. 55. To find the distance of a vertical object whose height is known. Method. — Measure the angle of elevation to the top of the object, as before; we will then have a right-angled triangle in PLANE TRIGONOMETRY. 31 which we know the perpendicular and an acute angle ; hence, wa can "readily find the base. D ' C 1. I took the angle of elevation to the top of a flagstaff whose height I knew to be 160 feet, and found it to be 20°; how far was I from the staff? Ans. 439.60 feet. CASE III. 56. To find the distance of an inaccessible object.. Method. — Measure a horizontal base-line AB, and then take the angles formed by this line and lines from the object to the extremities of this base-line, as CAB and ABC; the distance .4 Cor BC can then be readily found. 1. I am on one side of a river, and wish to know the distance to a tree on the other side. I measure 300 yards by the side of the river, and find that' the two angles formed by this line and the lines from its extremities to the tree are 72° 40' and 45° 36'; required the distance from each extremity of the base-line to the tree. Ans. 243.362 yards ; 325.15 yards. CASE IV. 57. To find the distance between two objects separated by an impassable barrier. Method. — Select any convenient station, as C, and measure the distance from it to each of the objects A anrf-B, and the angle C included between these lines. We can then readily find the distance AB. 1. The distance between two trees can- riot be directly measured : I therefore take a third position from 32 PLANE TRIGONOMETRY. which each of the trees can be seen, and find the distances from it to the trees to be 300 and 250 yards, and the included angle 43° 16' ; required the distance between the trees. Ans. 208.02 yards. CASE V. 58. To find the height of a vertical object standing upon an inclined plane. Method. — Measure any convenient ' js^ distance AD on a line from the foot of the object, and at the point D mea- sure the angles of elevation, EDA and / / -^E .EZXB, to foot and top of the tower By means of the two triangles DEA and DEB, we can find the height of AB. 1. Wishing to determine the height of a tower situated upon a hill, I measured a distance down the slope of the hill 400 feet, and found the angles of elevation to the foot of the tower 42'' 28', and to the top of the tower 68° 42' ; required the height of the tower. Ans. 486.747. CASE VI. 59. To find the height of an inaccessible object above a horizontal plane. First Method. — Measure any con- venient horizontal line AB directly toward the object, and take the an- gles of elevation at A and B; we will then have conditions sufficient to find DC. 1. "Wishing to find the altitude of a hill, I measured the, angle of elevation at the bottom 60° 37', and 460 feet from the foot in a right line of the top of the hill and the point at the foot, and in the same horizontal plane as the foot, I measured the angle of elevation 36° 52'; required the height of the hill. Ans. 597.092. Second Method. — If it is not convenient to measure a horizontal base'. PLANE TRIGONOMETRY. 33 tine towards the object, w& measure any line AB, and also measure the hori- zontal angles BAD, ABD, and the angle of elevation DBC.\ Then, by means of the two triangles ABD and CBD, the height CD can be found. CASE VII. 60. To find the distance between two inaccessible objects when points can be found at which both objects can be seen. Method. — The method of measurement is indicated in the following problem. The method of solution we prefer leaving to the ingenuity of the pupil, that he may learn to think for himself. 1. "Wishing to know the horizontal dis- tance between a tree and house on the opposite side- of a river, I took the fol- lowing measurements : AB = 400 ; CAD = 56° 30', BAD = 42° 24' ; ABC= 44° 36', and DBC= 68° 50'. Eequired the distance CD. Ans. 747.913. CASE VIII. 61. To find the distance between two inaccessible objects when no points can be found from which both objects can be seen. Method. — The method is in- dicated in the following pro- blem and figure. This and the following case may be omitted with young pupils. 1. "Wishing to know the hori- zontal distance between two in- 34 PLANE TRIGONOMETRY. accessible objects when no point can be found from which both objects can be seen, two objects Cand D are taken, 600 feet apart, from the former of which A can be seen, from the latter -B.. From .Cwe measure the distance CF, not in the direction DC, equal to 600 feet, and from D a distance DE equal to 600 feet. We then measure the following angles : CFA = 80° 16', BED = 86° 25', ACF= 52° 24', BDE = 60° 24', ACD= 56° 36', BDO= 150° 30'. Required the distance AB. Ans. 1117.44 feet. CASE IX. 62. To find the distances from a given point to three objects whose dis- tances from each other are known. Method. — The method is indicated in the problem and figure. 1. I wish to locate three buoys, A, B, and C, in a harbor, so that the distance between A and B is 800 yards, between A and C 600 yards, between B and C 400 yards, and from a fixed point on shore, the angle. APC shall equal 33° 45', and BPC 22° 30' ; required the distances PA, PC, and PB. Ans. PA = 710.193 ; PC= 1042.522 ; PB = 934.291. Note. — This last problem is given by quite a number of authors, and seem? to ba general property. ANALYTICAL TRIGONOMETRY. 35 ANALYTICAL TRIGONOMETRY. 63. Analytical Trigonometry is that branch of Mathe- matics which treats of the properties and relations of trigono- metrical functions. 64. Trigonometry,' in its origin, was confined to triangles, the method of reasoning being geometrical. After the invention of - analysis, mathematicians began to apply it to trigonometry, and, in course of time, developed the general properties of trigono- metrical functions. This has enlarged the science and greatly increased its power as an instrument of investigation and dis- covery. DEFINITIONS. 63. A circumference consists of four quadrants. AB is the first quadrant; BG is the second quadrant, etc. 66. The origin of arcs is at A, all arcs being generally supposed to begin at A. 67. The extremity of an arc is where it ends. An aro is said to be in that quadrant where its exti-emity is situated. 68. The sine, cosine, tangent, cotangent, etc. of an arc have already been defined, and need not be repeated here. ■ The versed sine of an arc is the distance from the foot of the sine to the origin of the arc. The co-versed sine is the versed sine of the complement. The sines, cosines, etc. are called the circular functions of the arcs. 69. Fundamental formulas expressing the relation between the circular functions of any arc. 1. Let a represent the measuring arc of any angle. Draw the lines represented in the figure. Then, from the definitions/ 36 ANALYTICAL TRIGONOMETRY. AB =1, BE = tan a, CD = sin a, AE = sec a, AD = cos a, DB = ver sin a. In the right-angled triangle ADC, we have, CD 2 + AD 1 = AC 2 , or, by substitution, sin 2 a + cos 2 a = 1. (1) Hence, sin 2 a=l — cos 2 a; (2) cos 2 a = l — sin 2 a. (3) 2. From the figure, we also have, DB = AB — AD; that is, ver sin a = 1 — cos a. " (4) Since this is true for any value of a, it is true for 90° — a; hence, ver sin (90° — a) = 1 — cos (90° — a), or, co-ver sin a = 1 — sin a. (5) 3. Again, the triangles ADC and ABE being similar, EB : AB : : CD : ^LD, or, tan a : 1 : : sin a : cos a; , sin a hence, tan a = ■ (6) cos a v ' Substituting 90° — a for a, we have, ,„™ , sin (90° — a) tan (90° — a = ~ {, K ' cos (90 — a) cos a or, cot a = — — . f 7 ) sin a v ' 4. Again, multiplying equations (6) and (7), we have, tan a cot a = 1 ; (8) hence, tan a = — r— (9), and cot a = . (10) cot a v " tan a v ' 5. Again, from the same triangles, we have, AE : AB : : AC : AD, or, sec a : 1 : : 1 : cos a; hence, seea = • (11) ' cos a * ' Substituting 90° — a for a, sec(90°-a) = co8(9( ; o _ g) , or. cosec a = — — « (121 ANALYTICAL TRIGONOMETRY. 37 6. Again, from the triangle ABE, we have, sec 2 a = 1 + tan 2 a ; (13) hence, cosec 2 a = 1 + cot 2 a. (14) 70. These are the fundamental formulas of trigonometry, and should be committed to memory. We will collect thern, forming the following table : 1. Sin 2 a -\- cos 2 a = 2. Sin 2 a 3. Cos 2 a 4. Ver sin a 5. Co-ver sin a 6. Tan a 7. Cot a 8. Tan a cot a = 1 = 1 — cos 2 a = 1 — sin 2 a = 1 — cos ffi = 1 — sin a = sin a cos a cos a sin a 1 9. Tan o = 10. Cot a = 11. Sec a = 12. Co-sec a = 13. Sec 2 a = 14. Co-sec 2 a = cot a 1 tan a 1 cos a 1 sin a l + tan 2 a 1 -f- cot 2 a ALGEBRAIC SIGNS OF- THE CIRCULAR FUNCTIONS. 71. In analytical trigonometry, we regard the algebraic signs of the functions as well as their numerical value. The sign of a function is determined by the following principles. 1. All lines estimated upward from the horizontal diameter are positive; all lines estimated downward from it are negative. 2. All lines estimated from the vertical diameter towards the right are positive ; all lines estimated toward the left are negative. Thus, the sines NP and WP' are positive, while N"P" and N"'P'" are negative ; so also the cosines OP and OP'" are positive, while OP' and OP" are negative. 72. The simplest way to determine the algebraic signs of the different functions is to derive those of the sine and cosine from'the figure, and the others from the formulas. 18 38 ANALYTICAL TRIGONOMETRY. 1. The Sine is positive in the first and second quadrants, being measured above, and negative in the third and/ourtA quadrants. 2. The Cosine is positive in theirs* and fourth quadrants, and negative in the second and third quadrants. 3. The Tangent is positive in the first and third quadrants, and negative in the second and fourth. For, from formula (6), sin a tan a = > cos a and this is positive when sine and cosine have like signs, and negative when they have unlike signs. In the first quadrant, both sine and cosine are plus, in the third both are minus, in the second and fourth one is plus and the other minus ; hence, the tangent is positive in the first and third quadrants and nega' tive in the second and fourth. , 4. The Cotangent is positive in the first and third quadrants, and negative in the second and fourth; as is readily shown from the formula, cos a cot a = —. . sin a 5. The Secant is positive in the first ondfourth quadrants, and negative in the second and third. For, from formula (11), 1 sec a = ; cos a hence, the secant has the same sign as the cosine. 6. The Co-secant is positive in the first and second quadrants, and negative in the third and fourth, as may be shown from For. (12). Note. — Some of these may also be readily shown from the figure. In the seaant, when the distance is estimated toward the extremity of the arc, it is plus ; when from the extremity, minus. LIMITING VALUES OF THE CIRCULAR FUNCTIONS. 73. The limiting values of the circular functions are their values at the beginning and end of the different quadrants. These values are determined by the principle that the value of a variable quantity up to the limit is its value at the limit. ANALYTICAL TRIGONOMETRY. 39 Beginning at the origin, we see that the value of sin is 0, and the cos is the radius, or 1. As the arc increases, the sine increases and the cosine decreases, until at 90° the sine is 1 and the cosine 0. As the are increases from 90° to 180°, the sine decreases and cosine increases numerically (diminishes algebraically), until at 180° the sine is + and cosine — 1. In the same way we see that sin 270° = — 1, and cos 270° = — ; also, sin 360° =— 0, and co- sine 360° =1. Now, since, by formula (6), sin a cos a sin cos " cosO substituting for a, and, also, tan a = tanO : cot0 = if- 1 sin " 74. By a similar examination of the limiting values of all tho functions, we have the following table : TABLE II. Arc = Arc = 90° Arc = = 180° Arc = = 270° Arc = = 360° Bin = sin = 1 Bin = sin = — 1 sin = — cos = 1 cos =■ cos. — — 1 cos — — o cos = 1 v-sin = v-sm = 1 v-sin = 2 v-sin = 1 v-sin = o co-v-sin = 1 co-T-sm = co-v-sin = • 1 co-v-sin = 2 co-v-Bin = 1 tan = tan = OO tan = — tan = OO tan = _ o cot = 00 cot — cot = — OO cot = cot = CO sec = 1 see = OO sec = — 1 sec = OO sec = 1 cosec = 00 COB6C = 1 cosec = OO cosec = — 1 cosec = CO FUNCTIONS OF THE SUM OR DIFFERENCE OF AN ARC AND ANY NUMBER OF QUADRANTS. 75. The trigonometrical function of any arc formed by adding an arc to or subtracting it from any number of quadrants, may be expressed in functions of the arc which is added to or subtracted from. 1. Let a represent any arc less than 90°; then, from the defini- tions, we have, 4C ANALYTICAL TRIGONOMETRY. sin (90° — a) = cos a, cot (90° -a) = tan a, cos (90° — a) = sin a, sec (90° — a) = cosec a, tan (90° — a) — cot a, cosec (90° — a) = sec a. 2. Now, let a represent the arc -BJV', then will ABW =^90° + a. From the figure, Art. 71, we see that WM' = sin a, ilf'O =cosa, P'O = cos (90° + a), JV'P' = sin (90° + a). Hence, remembering that ABW, being in the second quadrant, its cosine is negative, we have, sin (90° + a) = cos a, and cos (90° + a) = — sin a. Substituting these values in the formulas for tan, cot, etc. found in Table L, we have, tan (90° + a) — — cot a, sec (90° + a) = — cosec a, cot (90° + a) = — tan a, cosec (90° -|- a) = sec a. 3. Again, let a represent the arc CW, then will ABW = 180 — a. From the figure, we have, _ZV" / P / = sin a, P'0= cos a, 2^' = sin (180 — a), P / 0= cos (180 — a). Hence, remembering that the cosine of ABW ending' in tl*e second quadrant is negative, we have, sin (180° — a) = sin a, and cos (180° — a) = — cos a. Substituting these values in the formulas for tan, cot, etc. in Table I., we have, tan (180° — a) = — tana, sec (180° — a) = — seca, cot (180° — a) = — cot a, cosec (180° — a) = cosec a. From the above, we see that the sine of an arc equals the sine of its tupplement, and the cosine of an arc equals minus the cosine of its sup- plement, etc. 76. In a similar manner, by deriving the values of the sines and cosines from the figure and making the substitutions in ths proper formulas, we may obtain the functions of 180°+ a, 270° — a, 270° + a, and 360° — a. All of these, with the above, are exhi' bited in the following table : ANALYTICAL TRIGONOMETRY. 41 Bin = COS: tan: sin = COS: tan: sin: COS: tan: TABLE III. Arc = 90° + a. cos a, cot = — tana, -sin a, sec = — cosec a, cos=- -cota, cosec = sec a. tan = Arc =180° — a. sin a, cot = — cot a, -cos a, sec = — sec a, -tan a, cosec = cosec a. Arc = 180° + a. - siu a, cot = cot a, - C9S a, sec = — sec a, tan a, cosec = — cosec a. Arc = 270°-* a. - cos a, cot = tan a, ■ sin a, sec = — cosec a, cot a, cosec = — sec a. sm = cos = tan: SID : cos = tan: Arc = 270° -fa -cos a, cot = — sin d, sec = -cot a, cosec = — tan a, cosec a,, sec a. Arc = 360° — a. -sin a, cot = — cot a, cos a, sec = sec a, -tana, cosec = — cosec a. 77. This table can easily be committed to memory, by observing that when the arc is connected with 180° or 360°, the functions in both columns have the same name; but when connected with 90° or 270°, the functions in the two columns have different names. 78. The principles of this table are of great value. By their means the functions of any arc may be expressed in functions of an arc lest than 90°. Thus, sin. 120° = sin ( 90° + 30°) = cos 30°, tan 243° = tan (180° + 63°) = tan 63°, cot 304° = cot (270° + 34°) = — tan 34°. 79. When the arc is greater than 360°, we may subtract 360° one or more times until we obtain an arc less than 360°; the remainder will have the same origin and extremity: hence, the cir- cular function of the remainder will be the same as of the given arc, and this remainder being less than 360°, its functions can be expressed in functions of an arc less than 90°. Hence, the functions of any arc can be expressed in functions of an arc less than 90°. 19* 42 ANALYTICAL TRIGONOMETRY. CIRCULAR FUNCTIONS OF NEGATIVE ARCS. 80. Suppose AB to be any arc, and AC, esti- mated from the origin downward, be numeri- cally «3qual to AB; then, if the arc AB be J denoted by a, the arc AC will be denoted by — a; and CD will be the sine, and OD the co- sine, of — a. Now, since BD = CD and OD is the cosine of both a and — a, we have, sin ( — a) = — sin a, and cos ( — a) = cos a. Substituting these in the formulas of Table I., we will have, ver sin ( — a) = ver sin a, cot ( — a) = — pot a, co-ver sin ( — a) =± 1 + sin a, sec ( — a) = sec a, tan ( — a) = — tan a, co-sec ( — a) = — co-sec a. 81. From what has now been presented, we see that the circular functions .of all arcs, whether positive or negative, may be ex- pressed in functions of arcs less than 90°; hence, in the tablet of sines, cosines, etc., we have only positive arcs and those less than 90°. RELATION OF THE SIDES AND FUNCTIONS OF RIGHT-ANGLED TRIANGLES. 82. Let ACB be a right-angled triangle, the right angle being at A. Represent the angles by A, B, C, and their opposite sides by a, b, c. - With a radius \CE= 1, describe the arc EF, and draw the perpendicular ED; then ED = sin C, and GD = cosC. Now, from the figure, we readily obtain, 1 : sir C ::a:c, and, also, 1 : cob C :: a:b; hence, sin C^~ a (1), cosC=- (2), or, c = asih C (3), b =acos C (4). ANALYTICAL TRIGONOMETRY. 43 Dividing (1) by (2) and then (2) by (1), we have, tan C = ■ (5), cotC = - (6), ' b c or, c = 6tan C(7), and J = ccot C (8). 83. These the pupil will commit to memory, and also translate into common language. The first, thus translated, is as follows : 1. The sine of either acute angle of a right-angled triangle is. equal to the opposite side divided by the hypothenuse. 84. General formulas relating to the sum and difference of arcs, double arcs, etc. 1. Let AB and BG be two arcs having the common radius OA or OC= 1 ; denote AB by b and BC by a. From G draw CD perpendicular to OA, and CN perpendicular to OB; from N draw NE perpendicular to OA, and NM parallel to OA. Then, CD = sin (a + b), CN=sma, ON = coua. Now, CD=CM+NE. In the triangle OEN, NE = ON sin B = cos a sin b; since CMN and NOE are similar, and the angle MCN= NOE= 5, CM = CN cos b = sin a cos b. Substituting these values in equation (1), we have, sin (a + b) = sin a cos b + cos a sin b. (A) ~ This formula expresses the value of the sine of the sum of two arcs in terms of the sine and cosine of the single arcs. It is enunciated as follows : The sine of the sum of two arcs or angles is equal to the sine of the first into the cosine of the second, plus the cosine of thefltst into the sine of the D E A 2. If in formula (A) we substitute — b for b, we have, sin (a — b) = sin a cos ( — b) + cos a sin ( — b) ; but (Art. 80) cos( — b) =cosi, and sin (— &)= — sin6; hence 1 , sin (a — 5) = sinacos6 — cosasinJ. (B) 44- ANALYTICAL TRIGONOMETRY. 3. If in formula (B) we substitute 90° — a for a, we have, sin (90°— a — b) =sin (90°— a) cosb — cos (90° — a) sini,- but, sin (90°— a — &) = sin(90°— (a + b))=00B{a + b), and, sin (90° : — a) = cos a, and cos (90 — a) = sin a; hence, cos (a + b ) = cos a cos & — sin a sin 6. (C) 4. Substituting — b for 6 in formula (C), we have, cos (a — b) = cos a cos ( — 6) — sin a sin ( — b), or, cos (a — b) = cos a cos b-\- sin a sin J. (D) 5. From Table I., For. (6), and formulas (A) and (C), we have, . sin (a + 6) sin a cos b + cos a sin b tan (a + 6) = -. — ttt= 1 : ; — v x ' cos(a-)-o) cos a cos 6 — sin a sin 6 Dividing both terms of the last member by cos a cos b, we have, sin a cos b cos a sin b , , . . cos a cos b cos a cos b tan (a + o) = ; : — ; . sin a sin 6 cos a cos b Cancelling common factors, and reducing, we have, tan a 4- tan b ,„ tan (a + 5) = 1 _ tanatan& . (E) 6. Substituting — 5 for b in formula (E), and reducing, we have, , ,. tan a — tan b ,„, tan( a -6) = 1 + tanatan& . (F) 7. Dividing formula (C) by (A), and reducing as in (5), we have, it , i\ cotacoti — 1 cot (a + 6) = — n~-, 1 — • (Cr) ^ ' i cot b + cot a v ' 8. Substituting — b for 6 in formula (Gr), and reducing, we have, cot a cot b 4- 1 ,„, cot ("-*)= cot*-.coL - ( H ) 85. Formulas tor double and half arcs. 1. Making a = b in formulas (A), (C), (E), and (Gr), we have, sin 2 a = 2 sin a cos a; (A') cos 2 a = cos 2 a — sin 2 a, ((7) ALYTICAL TRIGONOMETRY. 45 2 tan a [W) 1 — taira cot 2 a — 1 cot2a = — s — i — •. (G')' 2. If now in (C) we put 1 — sin 2 a for cos 2 a, and then 1 -^ cos 2 a for sin 2 a, we have, cos2 — q), (L) cos^> + cosg = 2cos£ C?> + g) cosij (p — q), (M) . cosq — cos^> = 2sin£ (.p + g) sin £ (^> — g). (N) 3. Now, dividing (K) by (L), sin p + sin q ^ sin £ (p + g) cos £ (ff — g) _ tanj (p+ q) ^ sharp — sin q cos £{p + q) sin J {p — q) tan £ (p — q)' ^ ' In a similar manner, we obtain sinp + sing 2sin£(p + g)cos£b-g) cosp + cosg 2 cos £ (p + g) cos i [p — q) * ^ *" v ^' sin y -sin ? = 2smj(^- g )cosj(p + ? ) = ta eos^>+cosg 2 cos i (p-f-q) cos £ (^ — q) * ^ 3 ' v ' sin p + sin q _ 2smj [p + q) cos j [p — q) = cos jjp — q ) sin(j» + g) 2sin£(p + g) cos£ Qo + g) cosi(p + g)' *• sinp— sing _ 2 sin £(jp — g) cos£ (p + q ) _ sin £ (p — q) sin (p + g) 2 sin i (j» + g) cos £ (p + q) sin i (_p + q)' * ' sin (p — q) _ 2sml(p — q)cosi{p — q) _ cosb{p — q) sins — sing 2sini(p — g)cos£(^? + g) cos \ [p + g)' * These formulas may be enunciated in propositions ; thus for- mula (P) gives, The sum of the sines of two arcs is to the difference of their sines as the tangent of one-half of the sum of the arcs is to the tangent of one-half of their difference. ANALYTICAL TRIGONOMETRY. 47 Comparing (8) and (U), we have, sin (p — q) sin p -\- sin q smp — sing* sin (p + q) ' Hence, the sine of the difference of two arcs is to the difference of their sines as the sum of the sines is to the sine of the sum. INTRODUCTION OF THE RADIUS. 87. In the preceding formulas, the radius, being unity, does not appear in any of the terms. When the radius is other than a unit, it should appear in these formulas, and we will now show how it may be introduced. Let a be an arc whose radius is 1, and a' 2> be an arc whose radius is R; then, by simi- lar triangles, sin a: sin a': : 1 : R; _^ „ . . sin a' *A E B hence, sina / = JcX sma; sma=— =5— ; and the same may be shown for the other circular functions. Therefore, any circular function whose radius is R is equal to the cir- cular function whose radius is 1, multiplied by R. Also, any circular function whose radius is 1 is equal to the circular function whose radius is R, divided by R. Now, if we substitute these in any of the formulas, we will find that R will be introduced in such a manner as to make the for- mulas homogeneous. Thus, For. 6, Tab. I., gives, sin n? tan a' R R sin a' — — = .; or, tana' = - r . R cos a' cos a' R Here, tan a' is a line, and R sin a' -h- cos a' is a surface divided by a line, which is also a line; hence, the formula is homogeneous. And since the same is generally true, therefore, we can introduce the radius in any formula by multiplying or dividing by R, so as to make the formula homogeneous. 48 ANALYTICAL TRIGONOMETRY. CALCULATION OF A TABLE OF NATURAL SINES. 88. The circumference of a circle whose diameter is 1 is 3.14159 . . . .; hence, when the radius ia 1, the semi-circumference is 3.14159 .....; and if we divide this by 10800, the number of minutes in 180°, the quotient,, .000290888 , will be the length of an arc of one minute. Now, this arc is so small that it does not differ materially from its sine ; hence, we may assume .000290888 as the sine of one minute. We then find the cosine of V by For. 3, Table I. Thus, cos V = y/\ — sin* V = .999999957 (1) To find the sine of other arcs, we take the formula under Art. 86, - putting it in the form, sin (a -f- °) = 2 sin a cos b — sin (a — b). Now, make b = 1', and then in succession, a equal to V, 2', 3', etc., and we have, sin 2' = 2 sin V cos V — sin = .0005817764 sin 3' = 2 sin 2' cos V — sin V = .0008726646 sin 4' = etc. We may thus obtain the sines of any number of degrees and minutes up to 45°, the corresponding cosines being obtained from equation (1). Then, since the sine of an arc equals the cosine of its complement, etc., the sines and cosines of arcs between 45° and 90° are immediately derived from those between 0° and 45°. The tangents are found by dividing the sines by the cosines; the cotangents are found by dividing the cosines by the sines, or by dividing 1 by the tangents. CALCULATION OF A TABLE OF LOGARITHMIC SINES. 89. A table of logarithmic sines is computed from a table of natural sines. The process is as follows : For the logarithmic sine, take the logarithm of the natural sine, and add 10. For, let sin a represent the natural sine, and let Sin a represent the sine to a radius of 10,000,000,000 ; then, Art. 87, Sin a = sin ay^M; ANALYTICAL TRIGONOMETRY. 49 taking logarithms, we have, log Sin a == log sin a -(- log R. But log R = log 10,000,000,000 = 10 Hence, log Sin a = log sin a -)- 10. In the same manner, we find the log cosine ; and in a similar manner, from the formulas of Table I., we can find all the other logarithmic cir- cular functions. THEOREMS AND PROBLEMS. We now present a few exercises for original thought. The first and third are derived from a diagram ; the 5th by For. 2. Art. 84 ; several which follow, by substituting values from Table L, obtaining an equation involving but one unknown quantity, which can then readily be found ; the others, by judicious substitutions and reductions 1. Prove that sin 60° = \ y 3, and cos 60° = \. 2. Prove that sin 30° = £, and cos 30° = \ i/3. 3. Prove that sin and cos of 45° equal J yl. 4. Prove that tan 45° = 1, and sec 45° = -j/2. t/3 — 1 r/3 + 1 5. Provesml5°,orsin(60°— 45°)=-^y- 7 2-,andcosl5° = J: -2-^— . 6. Prove tan 15° = 2 — yS, and cot 15° = 2 + yS. 7. If sin a cos a = \ j/3 find sin a and cos a. Ans. sin os = J y"& ; cos a = \. 8. If 3 sin a -\- 5 yS X cos a = 9, find sin a. Ans. sin a = \ or \. 9. If sin a (sin a — cos a) = ^, find sin a. Ans. sin a = -|. 10. If tan a = f , find sin a and cos a. Ans. sin a = £ ; cos a = J. - 11. If tan a -f- cot a = 2, find tan a. Ans. tan a = 1. 12. Prove that tan 2 a — sin 2 a = tan 2 a sin 2 , a. 13. Prove that sec 2 a cosec 2 a = sec 2 a + cosec 2 a. 4 14. Prove that sin (30° + a) + sin (30° — a) = cos a. 15. Prove that cos (60° + a) + cos (60° — a) = cos a. 16. If a + b + c = 180°, prove that tan a -\- tan J + tan c = tan a tan J tan c. 17. If a -f J + c = 90°, prove that cot a + cot b -\- cot c = cot a cot 5 cot c. Suggestion.— In 16th, tan (a + b) = tan (180° — 6), develop and simplify; and similarly in 17th. 20 A TABLE OF LOGARITHMS OF NUMBERS From 1 to 10,000. N. Log. N. Log. N. Log. N. Log. i o-oooooo 26 1-414973 5i 1-707570 76 1-880814 2 o-3oio3o 11 i-43i364 52 I -716003 77 1-886491 1-892085 3 o • 477 1"2 1 1 -447158 53 1-724276 78 4 o- 602060 V) i-4'>2398 54 1-732394 79 1-897627 5 0-698970 3o 1-477121 55 1 • 74o363 80 1 -90J090 1-908485 6 0-778151 3i 1-491362 56 1-748188 81 I 0-845098 32 1 -5o5i5o u 1-755875 82 1-913814 ■ 903090 33 i-5i85i4 1-763428 83 1-919078 9 ■ 954243 34 1 -53 1479 5 9 1-770852 84 1-924279 10 I -oooooo 35 1 ■ 544068 60 1 -7-78151 85 1 -929410 II i ; o4i393 36 1 • 5563o3 61 1 -78533o 86 1-934498 12 1-079181 1 - 1 1J943 U 1-568202 62 1-792392 87 1-939519 i3 1-579784 63 1-799341 88 1 -944483 U 1-146128 3 9 1 -591065 64 1-806181 89 1.949390 i5 1-176091 40 1 -602060 65 1-812913 90 1 -954243 16 1 -204120 41 1-612784 66 1-819544 9' 1 -959041 \l 1 > 23o44o 1-255273 42 1-623249 tl 1-826075 92 1-963788 43 1-633468 1-832509 93 1-968483 19 1-278754 44 1-643453 69 1-838840 94 1 -973128 20 1 -3oio3o -45 1 -6532 1 3 70 1-845098 9 5 1.977724 21 I-32221D 1-342423 46 1-662753 71 1 -85i258 96 1 -982271 22 47 1 -672098 72 i-85 7 333 u 1-986772 23 1-361728 48 1-681241 73 1-863323 1 -991226 24 I- 38021 1 49 1 -690196 74 1-869232 99 1 -995635 25 * 1.397940 5o 1 -698970 75 1-870061 100 2 - oooooo Eemabk. — In the following table, in the nine right- hand columns of each page, where the first or lead- ing figures change from 9's to O's, points or dots are introduced instead of the O's, to catch the eye^ and to indicate that from thence the two figures of the Log- arithm to be taken from the second column, stand in the next line below. 2 A TABLE OF LOGARITHMS 'PROM ] TO 10,000. N. 100 1 2 3 4 | 3 | 6 | 7 8 9 1). 000000 0434 0868 l3oi| 17341 2166 2598I 3029! 3461 38 9 i 432 101 4321 475i 5i8i 5609' 6o38J 6466' 6894I 7321 7748 8174 428 102 8600 9026 945i 0876! »3oo' »724 : Ii47! «5lo 1993 241 5 424 io3 012837 3259 368o 4100 4521 4940 536ol 5779 6197 6616 419 104 7033 745 1 7868' 8284 8700 9116 9532 9947 3252 3V64 1 4075 •36 1 •775 4896 416 Io5 021 189 i6o3 2016 2428 2841 4486 412 106 53o6 5715 6i25 6533 6o42 735o| 7-571 8164 8571 8978 408 108 9384 9789 3826 •195 *6oo 1004 14081 18121 2216 2619 3021 404 o3c(424 4227 4628 5029 543oi 583o 6?3o 6629 7026 4"0 109 7426 7825 822! 8620 90(7 9414 981 1 3362! 3755 •207 4U8 •602 •998 4932 883o 3 9 6 110 041 3q3 1787 21S2 2576 Xl 4540 3 9 3 38 9 1 ' 1 5323 5714 6io5 6495 7275! 7664 8o53 8442 113 921S 05307S 9606 3463 oyy3 »38o •766 1 1-53 i538i 1924 2309 2694 386 1 1 3 5 ->46 423o 461 3 4996 88o5 5378 5760 9i85i oo63 2 9 58j 3333 6142 6524 382 H4 6903 72R6 7666' 8046 8426 9942 •320 379 n5 060O9S 4458 1075 14J2 1825 2206 2582 3709 7443 4o83 376 n6 4«32 52o6 : 558o 5953 6326 6699 7°7 ' 78i5 3 7 2 "7 8180 8557 8928, 9298 2617' 2985 9668 3352 ••38 •407 •776 ii45 i5i4 36 9 nS 071882 225o 3 7 i8 4o85 445 1 4816 5i82 366 119 5547 5 VA 9543 3i44 6276 6640 7004 7368 773 1 8094 8457 8819 363 120 079181 9904 3oo3 •266 •626 •987 i347 1707 2067 2426 36o 121 082780 386 1 4219 4576 4934 5291 5647 9198 6004 357 122 636o i 6716 7071 7426 7781 8i36 8490 8845 9552 3071 355 i:3 0905 093422 •258 •611 • 9 63 i3i5 1667 2018 2370 2721 35i 124 3772 4122 4471 4820 5169 55i8 5866 62i5 6562 349 346 125 6910 100371 7257 7604 ; 9 5i 8298 8644 8990 2434 9335 9681 3i 19 ••26 126 0715 1059 i4o3 1747 2091 2777 3462 343 III 38o4 4U6 4487 4828 5i6g 8565 55io 585i 6191 653 1 6871 340 7210 7549 7888 8227 8903 9241 9 5 79 9916 3275 •253 338 129 110590 0926 1263 1 599 i 9 34 2270 26o5 2940 3609 335 i3o 1 13943 4277 46u 4944 6278 56u 5943 6276 9 586 6608 6940 333 i3i 7271 7603 ;g34 8265 85 9 5 8926 9256 9915 3i 9 8 6456 •245 33o~ |32 120574 0903 I23l i56o 1888 2216 2544 2871 3525 328 i33 3852 4178 45o4 483o 5i56 548! 58o6 6i3i 6781 325 134 7io5 7429 o655 7753 8076 8399 8722 9045 9 368 9690 ••12 323 i35 i3o334 0977 1298 1619 5$ 2260 258o 2900 3219 64o3 321 1 36 3539 3858 4ni 4496 4814 545 1 5769 6086 3i8 III 6721 0879 !43oi5 7037 7354 7671 7987 83o3 8618 8 9 34 9249 9D64 3i5 •194 •5o8 •822 n36 U5o 1763 2076 2389 2702 3i4 139 3327 6438 363g 6748 9835 3951 4263 4574 4885 5196 55o7 58 18 3n 140 146128 7058 7367 7676 7 9 85 8294 86o3 8911 309 141 9219 152288 9 52 7 •142 •449 • 7 56 38i5 io63 1370 1676 1982 307 142 2594 2900 32o5 35io 4120 4424 4728 5o32 3o5 143 5336 6640 5o43 6246 6549 6852 7154 745 7 •77 5 9 8061 3o3 144 8362 8664 8965 9266 9567 9868 •168 •469 •769 ,3758 1068 3oi 145 i6i368 1667 1967 2266 2564 2863 3i6i 3460 4o55 299 146 4353 465o 4947 5244 5541 5838 6i34 643o 6726 7022 297 147 7317 76i3 7908 0848 82o3 8497 U34 8792 9086 9 38o 967* 9968 2895 295 148 170262 o555 1141 1726 20.19 23 1 1 26o3 293 149 3i86 3478 3769 4060 43 5 1 4641 4o32 5222 55i2 58o2 2^9 i5o 176091 638 1 6670 6959 7248 7536 7825 8n3 8401 8689 1 558 i5i 8977 9264 9552 9839 •126 •4i3 •699! »985 3553, 383 9 1272 287 285 I 52 181844 2120 4973 78o3 241 5 2700 29H5 3270 4123 4407 153 4691 5259 55421 5825 6108 6391. 6674 6 9 56 7239 -283 154 7521 8084 8366! 8647 8928 92091 9490 2010 2289 9771 ^••5i 281 i55 190332 0612 0892 1171 i45i 1730 2567 2846 279 278 156 3i25 34o3 368 1 3959! 4237 45i4 4792 5069 5346 5623 i58 58991 6176 8607 8o32 201397] 1670 6453 6729 7005 7281 7556 7832 8107 8382 276 9206 9481! 9755 ••29 •3o3 •577 •85o 1 124 274 159 1943' 2216' 2488 2761 3o33' 33o5 3577 3848 272 N. 1 . 2 | 3 i 4 | 5 | 6 | 7 I 8 9 D. A TABLE OF LOGARITHMS FROM 1 TO' 10,000. N. 1, i 2 " 3' . i -5; 6 7 8 J 9 D.| 160 204120 4391 4663 4g34 5204 5475 5746 6016 6286J 6556 371 161 6826 1 7096 96 1 5 9783 7365 •7634 7904J 8173 •586 ! »853 8441 8710 8979I 9347 1654 1921 269 162 ••5 1 •3i9 112! 1 388 267 266 163 212188, 2454 2720 2986 3252 35i8 3783 4049 43 14 4579 164 4844 5109 5373 5638 5go2 6166 643o 6694 6o57 9 585 7221 264 i65 748| ; 7747 8010 8273 8536 8798 9060 9 323 9846 263 166 220108 0370 o63i 0892 n53 Ui4 l6 7 5 1036 4533 2196 2456 261 i6 7 ; 2716 2976; 3236 34g6 3755 4oi5 4274 4792 5o5i 259 258 168 53o 9 5568 5826i 6084 6342 6600 6858, 71 1 5 7372 7630 169 78871 8144 84oo 8657 8913 9170 9426! 9682 gg38 »ig3 256 170 230449 0704 0960 35o4 1 2 1 5 I47<>| 1724 1979J 2234 24881 2742 254 •7« 2996. 325o 37D7 401 1 1 4264 4517 477° 5o23 5276 253 172 5028 5 7 8i 6o33 6285- 6537 6789 7041 7292 7544' 7795 252 i 7 3 8046 8297 8548i 8799! 9049 1 9299! 955o 9800 ••5o # 3oo 25o '74 240549 0799 1 048 3286, 3534 1297 3782 1 546 1795 2044 2293 2541 2790 249 l 7 5 3o38 4o3o 4277 4525 4772 6019 6266 248 176 55i3 5759' 6006 6252 6499 6745 6991 Vl 1 7482, 7728 246 >77 ' 7973 8219' 8464 8709 8o54 1395 9198 i638 9443 9687 9932 '176 -245 178 25o42o 0664 0908 3338 ii5i 1881 2125 2368 2610 243 IE 2853 3096 358o 3822 4064 43o6 4548 4790 5o3i 242 255273 55i4 5 7 55 5996 83g8 6237 6477 6718 6n58 9355 7198 7439 241 181 7679 7918 81 58 8637 8877 9116 9594 g833 23g 238 182 26007 1 o3io o548 0787 1025 1263 i5oi 1739 1976 4346 2214 i83 245 1 2688 2925 3i62 3399 3636 3873 4109 4582 23 7 184 4818 5o54 5290 552,5 5761 5996 6232 6467 6702 6937 235 i85 7172 7406 7641 7875 81 10 8344 8378 8812 9046 9279 234 186 90i3 9746 9980 •2l3 •446 •679 •912 H44 i3 77 i6og 233 188 271842 2074 438 9 2J06 2538 2770 5o8i 3ooi 3233 3464 3696 3927 232 41 58 4620 485o 53u 5542 5772 6002 6232 23o 189 6462 6692 6921 7i5i 73So 7609 7838 8067 8296 8525 229 228 190 278754 8982 •9211 9439 9667 9896 •123 •35i •378 •806 191 28io33 1261 1488 1715 1942 2169 23g6 2622 2849 3075 227 192 ~ 33oi 3527 3753 3979 42o5 443i 4656 4882 5107 5332 226 193 555 7 5782 6007 6232 6456 6681 6905 7i3o 7354 7 5 7 8 225 194 7802 8026 8249 8473 8696 8926 9143 g366 o58g 9812 223 195 290035 0257 0480 0702 0925 1 147 i36g i5gi i8i3 2o34 222 196 2256 2478 2699 292a 3i4i 3363 3584 38o4 4025 4246 221 ■\u 4466 4687 4907 5i 27 ?5347 5567 5787 6007 6226 6446 220 6665 6884 7104 7323 7542 7761 7979 8198 8416 8635 219 2l8 199 8853 9071 9289 9507 9725 9943 •161 •378 •5g5 •8i3 200 3oio3o 1247 1464 1681 1898 4009 2114 233 r 2547 2764 2980 217 201 3196 3412 3628 .3844 ' 4275 4491 4706 4g2i 5i36 2l6 202 535i 5566 5 7 8i 5oq6 62 1 1 6425 663g 6854 7068 7282 2l5 303 7496 7710 9843 7924 8i37 835i 8564 8778 8991 g204 9417 2l3 204 963o ••56 •268 •481 •6 9 3 •906 1118 i33o 1 542 212 2o5 3in54 1966 2177 4289 2389 2600 28 1.2 3o23 3234 3445 3656 211 206 386 7 4078 4499 47<° 4920 5i3o 5340 555 1 5760 210 207 5970 6180 63 9 o 65g( 8689 6809 7018 7227 7436 7646 7854 209 208 208 8o63 8272 8481 8898 9106 93i4 9 522 9730 9938 1 20 9 320146 o354 o562 0769 0977 1 184 i3oi • 3458 1D90 180D 2012 207 ; 210 322219 2426 2633 283? 3o46 3252 3665 3871 4077 206 1. ( 1 211 4282 4488 4694 4899 695c 5io5 53 10 55i6 5721 5926 6i3i 205 212 6336 6541 6745 7i55 735g 7563 7767 7972 8176 204 113 838o 8583 8787 8991 9194 9398 9601 9805 •••£ •211 203 314 33o4i4 061" 0819 1022 1225 1427 i63o 1 832 2o34 2236 202 2l5 2438 2640 2842 3o44 3246 3447 3649 5658 385o 4o5i 4253 203 216 4454 4655 4856 5o57 5257 5458 . 5859 7 858 6o5g 8o58 6260 201 217 1 218 ' "»9 6460 6660 6860 706c 7260 7459 7659 820- 200 8456 340444 8656 C642 8855 0841 go54 Io3$ 9253 1237 945 1 1435 g65c 1632 9849 i83o ••47 2028 •246 2225 9 igo I98 N. ! | 1 1 2 J 3 ! A | 5 1 6 1 7 8 D. 20* i A TABLE OF LOGARITHMS FROM ] TO 10,000. N. 1 ' 3 4 5 6 7 8 9 D. 320 342423 2620 2817 3oi4 3212 3409 36o6 38o2 3999 4196 61 5 7 197 221 4392 4589 4785 4981 5i 7 8 5374 5570 5766 0962 196 222 6353 6549 6744 6939 7i35 733o 7525 7720 7915 81 10 i 9 5 223 83o5 85oo 8694 o636 8889 9083 9278 9472 9666 9860 ••54 '9-i 224 350248 0442 0829 1023 1216 1410 i6o3 1796 1989 i 9 3 225 2i83 2375 2568 2761 2o54 3i47 5o68 333 9 3532 3724 3916 5834 i 9 3 226 4108 43oi 4493 4685 4876 5260 5452 5643 192 127 328 6026 6217 6408 6599 6790 6981 7172 7363 7554 7744 .191 7 9 35 8l2D 83i6 85o6 8696 8886 9076 9266 9456 9646 190 229 9 835 ••25 •2l5 •404 •5o3 •783 •972 J 161 i35o 1 539 it lio 361728 1917 2io5 2294 2482 2671 2859 3o48 3236 3424 23l 36i2 38oo 3 9 88 5862 4176 .4363 455i 4739 4926 5u3 53oi 188 232 5488 56 7 5 6049 7915 6236 6423 6610 6796 6 9 83 8845 7169 ft 233 7356 7542 7729 8101 8287 •i43 8473 865 9 •5i3 9o3o 234 9216 9401 9 58 7 9772 9958 •328 •698 •883 i85 235 371068 1253 U37 1622 1806 '99i 383i 2175 236o 2544 2728 184 236 2912 3oo6 49J2 3280 3464 3647 401 5 4198 4382 4565 184 23t 238 4748 5n5 5298 5481 5664 5846 6029 6212 63g4 i83 65 7 7 83 9 8 6759 6942 7124 8943 73o6 7488 7670 9487 7862 8o34 8216 182 239 858o 8761 0073 9124 9306 9668 9849 ••3o 181 240 3802 1 1 0392 0754 0934 Hi5 1296 1476 1656 1837 3636 181 241 2017 2197 2377 2557 2737 2917 3o 97 3277 3456 180 242 38i5 3995 5 7 85 4174 5964 4353 4533 4712 4891 5070 5249 5428 % 243 56o6 6142 6321 6499 6677 6856 l£i 7212 8989 244 7 3 9° 7568 7746 7 ? 23 9698 8101 8279 8456 8634 i 7 8 245 9166 9343 9D20 9 8 7 5 ••5 1 •228 •4o5 •582 • 7 5 9 177 246 390935 1112 1288 1464 1641 1817 1993 2169 2345 2521 176. 248 2697 4452 2873 3o48 3224 34oo 35 7 5 3?5i 3926 4101 4277 176 4627 4802 4977 5i52 5326 55oi 56 7 6 585o 6025 i 7 5 249 6199 6374 6548 6722 6896 8634 7071 8808 7245 8981 7419 7592 7766 95ol 174 25o 397940 8114 8287 8461 9154 9328 i 7 3 25l 9614 9847 ••20 •192 •365 •538 •711 •883 Io56 1228 i 7 3 2D2 401401 i5 7 3 1745 1917 3635 2089 2261 2433 26o5 2777 2949 172 253 3 1 2 1 3292 3464 3807 3978 4149 4320 4492 4663 I7 1 254 4834 5oo5 5i 7 6 6881 5346 55i7 5688 5858 6029 6199 6370 171 255 6540 Bijio 7o5i 8749 7221 8918 73m 756i 7731 7901 8070 9764 !S 256 8240 8410 85 79 9087 9 25 7 9426 9&,5 25t 258 9933 ' *102 •271 •44o •609 229J •773 2461 •946 1114 1283 I45i IS' 41 1620 I78B 1956 2124 2629 43o5 2796 2964 3i32 259 33oo 3467 3635 38o3 3970 4i3 7 58o8 4472 463o 63o8 4806 167 260 414973 5i4o 5307 5474 5641 5974 7638 6141 6474 167 261 6641 6807 6973 •45 1 t3p6 8964 7472 7804 7970 8(35 166 262 83oi 8467 8633 9129 9 2 9 5 9460 9625 9791 i65 '..63 9956 •121 •286 •616 •781 •945 2090 mo 1278 U39 i65 264 421604 1788 iq33 3$ 2261 2426 2754 2918 3o82 164 265 3246 3410 35 7 4 3901 5534 4o65 4228 4392 4555 4718 164 266 4882 5o45 5208 53 7 i 6697 586o 6023 6186 6340 79 7 3 9591 i63 267 '268 65n 6674 6836 •6999 8621 7161 8 7 83 7324 8944 •55g 7486 7648 7811 162 8i35 8297 845a 9I06 9268 9429 162 269 9752 43 1 364 9914 ••7D i685 •236 •3 9 8 •720 •881 1042 1203 161 270 l523 1846 345o 2007 2167 2328 2488 2649 2809 161 2 7I 2969 3i3o 3290 4888 36io 3770 3930 5526 4090 4249 4409 160 272 4669 6i63 4729 5o48 5207 6798 8384 536 7 5685 5844 6004 1 59 273 6322 6481 6640 6957 8542 7116 72-5 7433 8859; 9<"7 7592 m 274 7751 9 333 7909 8067 9648 8226 8701 9173 275 9491 9806 9964 1 538 •122 •279 •437 »5o4 •752 2323 1 58 276 440909 1066 1224 i38i 1695 i852 2009 2166 i5 7 277 ?78 2480 2637 2793 2g5o 3io6 3263 3419 3576 3 7 32 3889 1 5 7 ' 4045 4201 4357 4Di3 4669 4825 4981 5i3 7 5293 5449 7003 1 56 »79 56o4 5760 I 5gi5 2 6071 3 6226 6382 6537 6092 6848 1 55 D, \N. 4 1 5 6 7 8 9 A TABLE OP LOGARITHMS FROM ! ro 10,000. 5 N. 1 " . I | 3 4 5 | 6 1 7 8 9 8552 D. 1 55 380 447i58 8706 73i3 8861 7468 7623 7778 7933 8088 8242 8397 281 9013 9170 9324 9478 9d33 9787 9941 ••95 1 633 1 54 282 450249 04 ^3 o557 071 1 o865 1018 1172 1326 1479 1 54 283 1786 1940 2093 2247 2400 2553 2706 2859 3oi2: 3 1 65 153 284 33i8 k 34 7 i 3624 3 777 3930 4082 4235 438 7 4540 4692 153 285 4848 '4997 5i5o 53o2 5454 56o6 5758 5910 6062 6214 152 286 "6366 65i8 6670 6821 6973 7125 8638 7276 7428 8940 7 5 79 77 3i l52 28 1 288 7882 8o33 8184 8336 8487 8789 9091 9242 i5i 9392 9543 9694 9845 9995 •146 •296 •447 1948 •597 2098 •748 i5i 289 460898 1048 1 198 i348 1499 1649 '799 2248 no 290 462398 2548 2697 2847 2 997 3i46 3296 3445 35 9 4 3744 i5o 291 38 9 3 5383 4042 4191 568o 434o 4490 463o 6126 4788 4936 5o85 5234 149 292 5532 5829 5 977 6274 6423 6571 6719 \% 293 6868 7016 8495 7164' 7312 8643 8790 746o 7608 77 56 7904 8o52 8200 294 8347 8 9 38 9085 9233 938o 9527 «998 9675 148 295 9822 9969 1438 •116! »263 •410 •55 7 •704 •85 r 1 U5 "47 296 47 1 292 2756 i585 1732 1878 2025 2171 23i8 2464 2610 146 297 298 2oo3 4362 3o4o! 3ro5| 33.41 45o8 4653 4799 5962! 61071 6232 3487 3633 3779 3925 538i 4071 146 4216 4944 6397 5090 5235 5526 146 299 5671 58i6 6542 6687 6832 6976 145 3oo 477121 8566 7266 871 1 7411 8855 7555i 7700 8999 1 9143 0438 o582 7844 7989 8i33 8278 8422 145 3ol 9287 943 1 9 5 7 5 97'9 9 863 144 302 480007 oiSi 0294 0725 0869 1012 n56 1299 2731 144 3o3 1443 1586 1729 1872 2016 2159 2302 2445 2588 143 3o4 2874 3oi6 3i5o 4585 33o2 3445 3587 3730 3872 4oi5 4i57 143 3o5 43oo 4442 47 2 7 4669 5on 5i53 5295 5437 5579 142 3o6 5721 5863 6oo5 6147 6289 643o 65 7 2 6714 6855 6997 142 307 7i38 855i 7280 7421 7 563 7794 7845 7986 8127 8269 8410 141 3o8 8692 8833 8974 9114 9255' 9396 9537 9°77 9818 141 309 9958 491362 ••99 •23g •38o •520 •66 1 1 «8oi •941 2341 1081 1222 140 3io l502 1642 1782 1922 3319 2062' 2201 2481 2621 140 3n 2760 2900 3o4o 3179 3458 35g7 3 7 3 7 3876 4oi5 13, 3l2 4r55 4294 4433 4572 471 1 485o 4989 5i28 5267 5406 1 3 9 3i3 5544 5683 5822 5960 6099 6238 63 7 6 65i5 6653 6791 i3 9 3i4 6930 83n 7068 8448 7206 7344 7483 8862 7621 •8999 77 59 7897 8o35 8i 7 3 i38 3i5 8586 8724 9137 9275 9412 955o 138 3i6 9687 9824 9962 ••99 •236 •374 •oil •648 2017* •783 •922 '37 3i8 001059 1 196 1 333 1470 1607 1744 1S80 2 1 54 2291 3655 \u 2427 2564 2700 2837 2973 4335 3 109 3246 3382 35i8 3 19 5odi5o 3927 4o63 4199 555 7 4471 4607 4743 4878 5oi4 1 36 320 5286 5421 56 9 3 5828 5964 6099 6234 6370 136 321 65o5 6640 6776 6911 7046 7181 73i6 745 1 7586 7721 135 322 7856 799' 9-"7 8126 8260 83g5 853o 8664 8799 8934 9068 i35 323 9203 9471 960& 9740 9874 •••9 •143 •277 •411 1 34 324 5io545 0679 o8i3 0947 1081 I2l5 1 349 1482 1616 1750 134 355 i883 2017 2l5l 2284 2418 255i 2684 2818 2951 3o84 i33 326 32i8 335i 3484 36i7 3700 3883 4016 4149 4282 44i4 133 327 4548 4681 48i3 4946 5079 52 1 1 5344 5476 5609 574i 133 328 58 7 4 6006 6139 6271 64o3 6535 6668 6800 6932 7064 132 3io 7196 7328 7460 7592 8909 7724 7855 7987 81 19 825i 8382 132 33o 5i85i4 8646 8777 9040 9171 93o3 9434 9 566 9697 i3i 33 1 9828 ogSg ••90 •221 •353 •48.' •6i5 •745 •876 1007 i3i 332 521138, 1269 1 1460 i53o 1661 1792 1922 2t>53 2i83 23i4 r3i 333 2444! 2575 2705 2835 2966 3096 3226 3356 3486 36i6 i3o 334 3746| 3876 4006 4 1 36 4266 4396 4526 4656 4785 4915' l3o 335 5o45 5 1 74 53o4 5434 5563 56 9 3 5822 5g5i 6081 6210' 129 336 6339 6460 65q8 6727 6856 6 9 85 ,7114 7243 7372 tSoi 129 8788 I2g 337 763o 7709' 78881 8016 8i45 8274 8402 853 1 8660 338 8917 9045 91741 93o2 o328! o456| o584 943o 9559 9687 9815 9943 ••72 ia8 33 9 530200 0712 0840 oo68| 1 096 1223 1 3 5 1 ' 128 " N. I 2 f 3 4 5 6 1 8 9 1 rs. 6 A TABLE OF LOGARITHMS FROM ] TO 10,000. N. I 2 3 4 5 6 7 | 8 9 D. 34o 531479 2734 1607 1734 1862 J99P 3'264 2117 2245 2372I 25oo 2627 128 341 2882 3009 3i36 3391 35.8 3645 1 3772 3899 127 m 4026 41 53 4280 4407 4534 4661 booi 4914 5o4i 5167 .'2 343 5294 6558 7819 5421 5547 56 7 4 58oo 5927 6180' 63o6 6432 344 345 6685 7945 68u 8071 6 9 3 7 8197 7063 8322 8448 73i5 85 7 4 7441 1 7567 8699' 8825 3$ 126 126 346 9076 9202 9 32 7 9432 o83o 9703 9829 9934 ••79 •204 125 347 348 640329 0455 o58o 0705 0955 1080 1203 i33o 1454 125 1579 1704 1829 1953 2078 2203 2327 2452, 2576 2701 125 349 2823 2930 3074 3199 3323 3447 3571 36g6 38so 4936, 5o6o 3944 124 330 544068 4192 543 1 43i6 4440 4564 4688 4812 5i83 124 331 5307 5555 56 7 8 5802 6925 ■6049 6172' 6296 6419 124 332 6543 6666 6789 6913 7036 8267 7i5 9 838 9 7282 85i2 74o5, 7629 8635,; 8758 7652 8881 123 353 7775 7898 8021 8144 123 354 goo3 9126 9249 0473 9 3 7 i 9494 9616 9739 9861 | 9984 •106 123 355 550228 o35i 0595 ° 7 ^ 1938 0840 0962 1084 1206 1328 122 356 i45o 1072 1694 1816 2060 2181 23o3 2425 2547 122 35t 358 2668 2790 2911 3o33 3i55 3276 4489 33 9 8 35i9 3640 3762 121 3883 4004 4126 4247 4368 4610 473i 4852 4973 6182 121 35 9 5094 521 5 5336 5457 55 7 8 6785 5699 6903 5820 5940 6061 121 36o 5563o3 6423 6544 6664 7026 7146 7267 738 7 858 9 120 36i 7507 8709 7627 8829 7748 8948 7868 7988 8108 8228 8349 8469 120 36a 9068 9188 93o8 9428 9548 9667 9787 120 363 9907 ••26 •146 •265 •385 •5o4 •624 •743 •863 •982 119 364 56noi 1221 i34o 1459 1578 1698 1817 1 936 2o55 2174 II9 365 2293 3481 2412 253i 265o 2769 2887 3oo6 3i25 3244 3362 119 366 36oo 3 7 i8 3837 3953 4074 5237 4192 43n 4429 4548 JB 361 368 4666 4784 4903 5021 5i3g 5376 5494 56 1 2 6730 .5848 5 9 66 6084 6202 6320 6437 6555 6673 679 r 6909 :i8 36g •370 7026 568202 7144 83i9 7262 8436 8554 7497 8671 7614 8788 7732 8 9 o5 7849 9023 7967 9140 8084 9257 118 117 3 7 i 9374 9491 9608 9725 9842 9959 ••76 •193 1 35 9 •309 •426 117 3 ^ 570543 0660 0776 0893 IOIO 1 1 26 1243 1476 l5o2 2765 "7 3 7 3 1709 2872 i825 1942 2038 2174 2291 3452 2407 3568 2523 2639 116 3 si 2988 3io4 3220 3336 3684 38oo 3 9 i5 116 Vi 4o3i 4i 47 4263 4379 5534 4494 565o 4610 4726 588o 4841 4957 5072 116 376 5i88 53o3 5419 5 7 65 5996 6111 6226 n5 m 6341 6457 6372 6687 6802 6917 7o32 7147 82 9 5 7262 8410 7377 8525 ii5 j! 4 ? 2 7607 8754 7722 8868 7836 8983 795 1 8066 8181 n5 379 863 9 9°97 9212 9326 9441 9 555 9669 114 38o 579784 580925 9898 1039 ••12 •126 •241 •355 •469 •583 •607 1 836 •811 114 38i u53 1267 i38i 1495 263 1 1608 1722 1960 114 382 2063 2177 2291 2404 25i8 2745 2858 2972 3o85 114 383 3 J?9 433 1 33i2 3426 3539 3652 3765 3870 3992, 4io5 4218 1.3 384 4444 4557 4670 4783 4896 j 5009 60241 6137 5122 1 5235 5348 n3 385 546i -5574 5686 5799 5912 625o 6362 6476 n3 386 658 7 6700 7823 8944 6812 6925 7037 7-149! 7 262 8272 8384 7374 1 7486 8496 8608 75 9 o 8720 ■9838 112 387 77ii 8832 7 9 35 8047 8160 112 388 9056 9167 9279 9 3 9' 95o3 96i5 9726 112 389 9950 ••61 •173 1287 •284 •396 •5o7 •619 •730 »842 1843 i 9 55 • 9 53 112 390 591065 1176 2288 l3 99 i5io 1621 1732 2843 2066 in 391 2177 2399 25io 2621 2732 2954 1 3o64 3i 7 5 111 3ol 3286 33 97 35o8 36i8 3729 3840 3950 4834: 4945; 5o55 4061 1 4171 4282 111 393 4393i 45o3 4614 4724 5i65 5276 ■5386 110 3 9 4 5496 1 56o6 0717 5827 5937. .6047 j 6157 6267 6377 6487 no 393 3g6 6597 6707 nt<)5\ 7805 8701 , 8900 9883| 9992 6009731 1082 6817 79'4 6927 8024 7037, 71461 7236 8i34 8243, 8353 7366, 7476 7586 8462 8572 8681 no no III 9009 9"9 9228, 9337 9446 •3io »428 »537 9556 9665 9774 •646 *755| «864 I734 ! i843! i 9 5i 109 •101 •210 109 399 1 191 I2Q9 1408 1517 1625 109 K. ll » ! 3 ! 4 i 5 '| 6 7 ! 8 | 9 B. A TABLE OF LOGARITHMS FROM 1 TO 10,000. N. | 1 | 2 3 4 | 5 6 | 7 | 8 9 1 D. 400 602060J 2169' 2277 3i44! 3253. 336i 2386 2494 26o3 27111 2819' 2928! 3o36 108 401 3469 3577: 3686' 3794 4658' 4766' 4874 3902 4oiO| 41 18, 108 402 42261 4334' 4442 455o 4982J 5089' 5197! 108 4o3 53o5 54i3 5521. 5628 3736' 5844! 5g5 1 6o5g 6i66i 6274' 108 7 i33i 7241! 7348, 10.7 82o5; 83 1 2 ' S419! 107 404 638i 6489 6096 6704 6811 6919 7026 40D 7455 t562 7669 8633; 8740 9701. 9808 7777 7884 8 9 54 7991 8098 .406 8526 8847 9061 9167 9274 g38l | 9488I 107 407 9 5 94 9914 ••21 •128 •234 •341 •447 •334i 107 408 610660 07671 0873 0979 1086 1 192 1298 i4o5 i5ii 1617 106 409 1723 1829' 1936 2042 2148 2234 236o 2466 2572 2678 106 410 612784 2890! 2996 3 102 3207 33i3 3419 4475 3525 363o 3736 106 411 3842 3947! 4033 4l5g 52i3 4264 4370 458 1 4686 4792 106 412 4897 5oo3 5 108 5319 5424 5529 5634 5740 5845 io5 4i3 59^0 6o55i 6160 6265 6370 6476 658 1 6686 6790 68g5 103 414 7000 7io5 7210 8 1 53 825 7 73i5 8362 7420 7525 7629 8676 7734 8780 783 9 7943 lo5 41 5 8048 8466 85 7 i 8884 8989 io5 416 9093 9198 9302 9406 90 1 1 9615 97'9 9824 9928 ••32 104 418 620106 0240 0344 0448 o552 0656 0760 0864 0968 1072 104 1.76 12S0 1384 1488 1592 i6o5 27J2 '799 2835 1903 2007 2110 104 419 2214 23i8 2421 5525 2628 2939 3 9 73 3o42 3i46 104 420 623249 3353 3456 3559 3663 3 7 66 386g 4076 4179 io3 421 4282 4385 4488 4591 4695 4798 4goi 5oo4 5 107 5210 io3 422 53i2 54i5 55i8 5621 5724 5827 5929 6o32 6i35 6238 io3 423 6340 6443 6546 6648 6751 6853 6956 7o58 8082 7161 8i85 7263 io3 424 7366 838g 7468 7571 85 9 3 7673 8693 7775 8797 j8 7 8 8900 7980 8287 93o8 102 425 8491 9002 9104 9206 102 426 9410 9512 9613 9715 98.7 9919 ••21 •123 •224 •326 102 428 630428 o53o o63i 0733 o835 0936 io38 1139 2153 1 241 1342 102 1444 1 545 1647 1748 1849 1951 2052 2255 2356 101 429 2457 633468 2559 2660 2761 2862 2963 3064 3i65 3266 -3367 101 43o 3569 3670 3771 38 7 2 3973 4074 4n5 5i82 4276 4376 100 43 1 4477 45 7 8 4679 4779 5785 4880 4981 5o8i 5283 5383 100 432 5484 5584 5683 5886 5 9 86 6087 6187 6287 6388 100 433 6488 6588 6688 6789 6889 6989 7089 8090 9088 7189 8190 9188 7290 8290 9287 7390 838g 93»7 lco 434 435 7490 8489 8589 7690 8689 779° 8789 8888 7990 8988 99 99 436 94S6 9 586 9686 9783 9 S85 99 8 4 ••84 •i83 •283 •38a 99 43t 438 6404S1 o58i 06S0 0779 0879 0978 1077 "77 1276 1375 99 1474 i573 1672 ■771 1871 1970 2069 2168 2267 2366 99 43g 2465 2563 2662 2761 2860 2959 3o58 3i56 3255 3354 99 44o 643453 355i 365o 3749 3847 3g46 4044 4i43 4242 434o 9 o 44 1 4439 4537 4636 4734 4832 493i 5029 5127 5226 5324 98 442 5422 5521 56 1 9 6717 58i5 5qi 3 6894 601 1 61 10 6208 63o6 ■ 9 2 443 6404 65o2 6600 6698 6796 6992 7089 7187 7285 9 « 444 7 .383 836o 7481 8458 7579 7676 7774 7872 8848 7969 8067 8i65 8262 98 445 8553 8653 8750 8943 9043 914a 9237 97 446 9 335 9432 953o 9627 9724 9821 9?'9 0890 ••16 •n3 •210 97 447 65o3o8 0403 0502 0599 0696 0793 0987 1084 1181 97 448 1278 i375 1472 1 569 1666 1762 1839 1936 2o53 2i5o 97 449 45o 2246 2343 2440 2536 2633 273o 2826 2923 3888 3oig 3i:6 9 l 9 2 , 653213 3309 4273 3403 3 302 35 9 8 3695 3791 4734 3984 4080 45i 4177 436 9 4465 4562 4658 485o 4946 5o42 96 ' 432 5i38 5235 533 1 5427 5523 5619 5 7 i5 58io 5go6 6864 6002 96 453 6098 70D6 6194 6290 6386 6482 6577 66 7 3 6769 6960 96 454 7162 7247 7343 7438 83g3 7534 7629 8584 7720 8679 78201 701b 87741 8870 96 455 801 1 8107 8202 8298 9230 •201 8488 95 456 457 8 9 65 9916 9060 ••11 9i55 °io6 9346 •296 9441 •3oi 9 536 •486 963i •58i 9726 9821 •676] 0771 9 l 9 l 458 66o865 0960 io55 n5o 1245 l33g 1434 1 S29 10231 I7lf 95 409 i8i3 1907 .2002; 2096I 2191I 2286' 238o 2473 2369 266; 95 N. I '2 | 3 i 4 1 5 | 6 i 7 | 8 j 9 | D. 8 A TABLE OP LOGARITHMS FROM ] TO 10,000. N. 1 2 3 4 1 5 j 6 | 7 j 8 9 D. 460 662758 2852 2947 3o4i 3i35i 323o| 3324! 34i8 4078' 4172? 4266! 4360 35i2 3607 94 461 3701 3795 4736 388g 3783 4454 4548 94 462 4642 483 4)24 5362 5oi8j 5u2 3206 5299 5393 633 1 5487 94 463 558 1 56 7 5 5769 5956' 6o5o 6l43 623^ 6424 94 464 465 65i8 7453 8386 6612 7546 670C 7640 85 7 2 b M 6892 7826 8759 6986 8852 80IJ 7173 8106 7266 8199 7360 8293 94 9^ 466 8479 8665 8945 9 o38 9i3i 9224 93 467 468 9 3ij 9410 95o3 9596 9689 9782 9 8 7 5 9967 ••60 •i53 9f J70246 o33 9 043i o524 061-; i543 0710 1636 0802 0,895 0988 1080 93 469 1173 1265 1358 I45i I728 1821 iqi3 2005 9 3 470 672098 2190 2283 2375 2467 256o 2652 2744 2836 2929 -385o 92 471 3o2I 3n3 32o5 3297 42i8 3390 3482 3574 3666 3758 92 472 3942 4861 4o34 4126 43io 4402 4494 4586 4677 4769 92 473 4q53 5o45 5i37 5228 5320 5412 55o3 55 9 5 568 7 92 474 5 77 8 6694 5870 6 7 85 5o62 bo53 6145 6236 6328 6419 7333 8245 65u 6602 92 475 6876 7789 8700 6968 7039 7 1 5i 8o63 7242 7424 8336 75i6 8427 91 476 itu 7698 8609 788, 8791 m 8i54 9> 477 478 8973 9882 9064 9 i55 9246 9337 9' 9428 9 5l 9 9610 9700 9791 9973 ••63 •i54 •245 9' 479 68o336 0426 o5i7 0607 i5i3 0698 0789 0879 0970 1874 1060 ii5i 9" 480 681241 1332 1422 i6o3 1693 1784 1964 2867 2055 90 481 SI45 2235 2326 2416 25o6 2596 2686 2777 2957 90 482 3047 3i37 3227 33i7 3407 3497 358 7 36 77 3767 4666 385 7 90 483 3 9 47 4o37 4127 4217 43o7 4396 4486 4576 4?56 5652 90 484 4845 4935 5o25 5ii4 5204 5294 6189 7083 5383 5473 5563 P 485 6742 583 1 5921 68i5 6010 6100 6279 6368 6458 6547 486 6636 6726 6904 6994 7172 8064 7261 81 53 735 1 8242 7440 833 1 a 9 487 488 7629 8420 7618 85oo 7707 85o8 7796 8687 7886 8776 I97 5 8865 £ 9 8o53 9042 9i3i 9220 o 9 489 9309 9 3n8 0280 9486 9 5 7 5 9664 9753 9841 9930 ••19 090D •107 "W93 1877 %> 490 690196 1 08 1 o3 7 3 0462 o55o 0639 0728 0816 89 491 1170 1258 1347 1435 1 524 1612 1700 1789 88 492 1965 2o53 2142 2230 23i8 2406 2494 2583 2671 2759 88 493 1847 2935 38i5 3o23 3 1 11 3199 3287 3375 3463 355i 363 9 88 494 3727 3903 3991 4078 4166 4254 4342 443 45i7 88 495 46o5 4693 4781 4868 4g56 5o44 5i3i 5219 53o7 53g4 -88 496 548 2 556 9 5657 5744. 5832 5919 6007 6094 6182 6269 a 7 497 498 6356 6444 653 1 6618 6706 6 79 3 6880 6968 7o55 7142 80 14 ? 7 7229 7317 8188 7404 8275 8362 75 7 8 8449 7660 8535 775-2- 8622 783 9 8709 7926 £ 7 499 8101 8796 8883 I 1 5oo 698970 9057 9144 9231 9317 9404 9491 9 5 7 8 9664 9 75i a 7 5oi 9838 9924 ••II ••98 •184 •271 •358 •444 •53 1 •617 ?7 502 700704 0790 0877 0963 io5o Ii36 1222 1 309 1395 1482 86 5o3 i568 16J4 1741 1827 lgl3 i?99 2086 2172J 2258 2344 86 5o4 243 1 25i7 26o3 2689 2 77 5 2861 2947 3o33 3i ig 32o5 86 5o5 32gi 4i5i 3377 3463 3549 3635 3721 3807 38o3 3979 4o65 86 . 5o6 4=36 4322 4408 4494 53 5o 4579 4665 4751 [ 4837 4922 86 507 5o8 5oo8 5094 5179 6o35 5265 5436 5522 5607! 5693 5 77 8 86 5S64 5o4q 68o3 6120 6206 6291 63 7 6 6462, 6547 6632 85 509. 6718 6888 6974 7o5g 7144 7229 8081 73i5| 7400 8166! 825i 7485 85 5io 707570 7655 7740 8591 7826 8676 791 1 8761 TP 6 8846 8336 85 5u 8421 85o6 8g3l 9015 9100 9185 85 5l2 • 9270 9355 9440 9D24 .9609 9694 9779 0625 9863 j 9948 ••33 85 5i3 710117 0202 0287 0371 0456 0540 0710' 0794 1 554; 1W9 0879 1 7 23 85 5U 0963 1807 1048 Il32 1217 >3oi 1 385 1470 84 5 1 5 1892 2734 1076 2060 2144 2229 23 13 2397 2481 2566 84 5i6 265o 2818 2902 2986 3070 3i54 3238 3323 3407 84 5, 1 5i8 3491 3575 365g 3742 3826 3910 3g94 4833 4078 4162 4246 84 433o 44i4 4497 458 1 4665 4749 4916 5ooo 5o84 84 5l9 5167 525i 5335 54i8 55o2 5586 566 9 5^53 5836 5920 84 W. I 2 3 4 | 5 6 7 1 8 I 9 j A TABLE OF LOGARITHMS FROM 1 TO 10,000. N. 530 521 522 5j3 bJ4 525 526 521 528 529 '53o ,53i 532 533 534 "535 536 53 7 538 53 9 54o 541 542 543 544 545 546 54t 548 549 55o 55i 502 553 554 555 556 557 558 55g 56o 56i . 562 563 564 565 566 56 7 568 56 9 570 5 7 i 572 5 7 3 574 575 576 ill J>79 N. 716003, 6087 6170 683S, 6921 j 7004 7671 7754' 7837 85o2l 8585 1 8668 9 33 4, 720159 0986 1811 2634 3456 724276 6095 5912 6727 7541 8354 9i65 9974 730782 1 58 9 732394 3197 3999 4800 5599 6397 7 ig3 I^ 1 8781 9072 74o363 -Il52 i 9 3 ? 2720 35io 4293 5075 5855 6634 7412 -48188 8963 70o5o8 1271 204! 2816 3583 4348 5i 1 2 755875 6636 $5 8912 9668 760422 1176 1928 2679 94Ui 0242 •1068 l8 9 3 2716 3538 4358 6176 5993 6809 7623 8435 9246 ••55 o863 1669 2474 6254! 633} 7088, 7171 9497 o323 n5i " 97 8 2798 3620 4440 5258 6073 6890 7704 85i6 9327 •i36 0944 1750 2555 3278| 3358 4160 4960 4 S 9 4880 6679 6476 7272 8067 8860 9651 0442 1230 2018 2804 3588 4371 5i53 5 9 33 6712 I' ■ 8266 9040 9814 0586 i356 2125 2893 366o 4425 5189 SgSl 6712 7472 823o 8988 9743 0498 I25l 2oo3 2754 792c 875 1 9580 1233 2o58 2881 3702 8oo3 8834 9 663 0490 i3i6 2140 2963 3i84 4.6221 4604 5340 5422 5 7 59 6556 7352 8146 8 9 39 973" 0521 i3o9 2096 2882 3667 4449 5231 601 1 6790 9118 989 6663 1433 2202 2970 3736 45ol 5265 6027 6788 7548 83o6 9063 9811 057. 1326 2078 2829 6i56 6972 ll 9 n 9408 •217 1024 1 83o 2635 3438 4240 5o4o 5838 6635 743i 8225 9018 9810 0600 1388 2175 2961 3 7 45 4528 53o9 6089 '6868 7645 8421 s# 0740 i5io 2279 3o47 38i3 45 7 8 5341 6io3 6864 7624 8382 9i3 9 9894 0649 1402 2i53 2904! 6238 7053 7866 8678 9481 •29) no5 191 1 271 5 35i8 4320 5l20 5 9 i8 6715 7311 8.3o5 909 067& 1467 2254 3o3q 3823 4606 5387 6167 6945 7722 8498 nil 0817 1 587 2356 3i23 3889 4654 54i7 6180 6940 7700 8458 9214 9970 0724 1477 22;8 2978 6421 7204 8086 8917 9745 0673 i3g8 2222 3043 3866 4685 55o3 6320 7i34 7' 8759 9570 •378 1 186 1991 2796 35 9 8 4400 5200 5998 6795 7590 8384 9177 9968 0757 1546 2332 3n8 3902 4684 5465 6245 7023 7800 85 7 6 935o •i23. 089 1664 2433 3200 3966 4730 5494 6256 7016 7775 8533 9290 ••45 •0799 1 552 23o3 3o53 65o4 7338 8169 9000 9828 o655 1481 23o5 3127 3948 476] 5585 6401 7216 8029 8841 9651 •45o 1266 2072 2876 3679 4480 5279 6078 6874 7670 8463 9256 ••47 o836 1624 241 1 3i 9 6 3g8o 4762 5543 6323 7101 7878 8653 9427 •200 0971 1741 25o9 3277 4042 4807 5570 6332 7092 7801 8609 9 366 •121 0875 1627 2378 3i28 9 I 6588 7421 8253 9 o83 99" o 7 38 1 563 2387 3209 4o3o 4849 5667 6483 7297 81 10 8922 97 32 •540 1347 2 1 52 2g56 3 7 59 456o 5359 61 57 6 9 54 774< 854: 9 335 S126 0915 !7o3 2489 32 7 5 4058 4840 562 6401 7'7' 79 5: 8731 9604 •277 1048 isr 2586 3353 4119 4883 5646 6408 7168 7927 8685 9441 •196 0900 1702 2453 32o3 D. 6671! 6 7 54! 83 75o4' 7587I 83 8336! 8419; 83 9160, 9248 9994 0821 1646 2469 3291 4112 '77 0903 1728 2552 3374 4194 493i| 5oi3 5748 583o 65641 6646 7 3 79 8191 9003 9813 •621 1428 2233 3o37 3839 4640 5439 6237 7o3. 7829 8622 94U •2o5 0994 1782 2568 3353 4i36 5699 6479 7256 8o33 8808 g582 •354 1 1 25 1895 2663 343o 4195 4960 6722 6484 7244 8oo3 8761 9 51 7 •272 1025 1778 2529 3278 460 8273 9084 9893 •702 i5o8 23i3 3117 3919 4720 55i9 63i7 7ii3 7908 8701 9493 •284 1073 i860 2647 343 1 42i5 4997 3777 6556 7334 8110 9659 •43 1 1202 1972 2740 35o6 4272 5o36 5799 656o 7320 8079 8836 9 5 9 2 •347 1:01 1 853 2604 3353| 75 10 A TABLE OP LOGARITHMS FROM 1 TO 10,000. N. THo" OI! 3 -| 4 5 6 | 7 8 9 D. 763428 35o3 3578 36531 3727 38o2 3877! 3 9 52i 4027 4101 75 58i 4176 4261 1 4326| 44oo 4475 455o 4624 46 99 ' 477/ 4848 75 5S2 4923 4998 50721 5i4- 5221 52 9 6! 5370! 5445j 552c 55 9 4 75 583 566 9 64i3 5743 58i8 58 9 2 6636 5 9 66 6041 6110! 6igo 6264 6338 74 584 6487 6562 6710 6 7 85 685 9 6 9 33[ 700' 7082 74 585 7i56 723o 73o4 8120 7453 8104 8o3< 7527 8268 7601 8342 7675; 7749 8416! 8490 91 56j 9230 7823 74 586 7898 8638 7972 8712 8046 856; 74, 58 7 8786 8860 9 ooE 9082 9 3oc 74 588 93?7 9 45i 9 525 9599 o336 9073 9746 9820 9894: 9 9 6S ••42 74 58 9 7701 13 oi8 9 0263 0410 0484 o55] 1293 o63i 0705 0778 74 590 770852 9 20 "999 1734 1073 1 146 1220 1367 1440 i5i4 74 591 1387 1661 1808 1881 i 9 55 2028 2102 217J 2248 73 5g2 2322 23 9 5 2468 2542 26i5 2688 2762 2835 2 9 o8 2 9 8l 73 5 9 3 3o55 3i28 3201 3274 3348 3421 3494 3567 3640 37i3 73 ^i 3786 386o 3 9 33 4006 4079 4i52 4225 42 9 8 4371 4444 73 5 9 5 45i7 4590 4663 4736 48o 9 4882 4 9 55 5o28 5ioo 5n3 73 5 9 6 52/,6 5319 53 9 2 5465 5538 56io 5683 5 7 56 582 9 5 9 02 73 III 5 97 4 6047 6120 6 I9 3 6260 6338 641 1 6483 6556 6629 73 6701 6774 6846 6 9 i 9 6 99 2 7064 7'37 720 9 7282 8006 7354 ' 73 5 99 7427 778151 74 99 7572 8296 7644 8368 77H 8441 7789 85i3 7862 8585 7 9 34 8658 8079 72 POO 8224 8 7 3o 8802 72 601 8874 8047 9019 9 S 9 I 9 i63 9 236 9 3o8 9 38o 9452 9 524 72 602 9 5 9 6 9 66 9 974i 9 8i3 9 885 99 5 7 "2 9 •101 •173 •245 72 6o3 780317 o38 9 0461 o533 o6o5 0677 i3go °74 9 0821 o8 9 3 o 9 65 72 604 1037 II0 9 1181 1253 1324 1468 1 54o 1612 1684 72 6o5 1755 1827 i8 99 1931 2688 2042 2114 2186 2258 2329 2401 72 606 2473 3i8 9 2544 2616 27 5g 3476 4189 283 1 2902 36i8 2 97 4 368o 44o3 3o46 3i 17 72 607 3260 3332 34o3 3546 3 7 6i 3832 7' 608 3 9 o4 3 9 75 4046 4i 18 4261 4332 4475 4546 7' 609 4617 468 9 4760 483 1 "4g02 4 9 74 5686 5o45 5n6 5187 5259 7i 610 78533o 54oi 5472 6i83 5543 56i5 5 7 5 7 6828 58 99 5970 6680 7« 611 6041 6112 6254 6325 63 9 6 6467 6538 6609 7i 612 6751 6822 68 9 3 6 9 64 7o35 7106 788^ 85 9 3 7248 7319 8098 71 6i3 7460 8168 7?3 1 823 9 7602 M 7744 845 1 78i5 8522 7 9 56 8663 8027 7« 014 83io 8734 8804 7' 6i5 8875 9 58i 8946 9016 9 o8 7 9 'Jl 9 228 9299 9369 9 44o 9 5io 7i 616 9 65i 9722 9792 9 863 9933 •••4 "7,4 •144 •2l5 70 6, l 618 790285 o356 0426 04 9 6 0567 0637 0707 o 7 |8 1480 0848 0918 70 0988 1059 1 1 29 1199 I26 9 1340 1410 i55o 1620 70 6*9 1691 1 761 i83i 1901 1071 2672 2041 2111 2181 2252 2322 7" 620 792392 2462 2532 2602 2742 2812 2882 2 9 52 3022 70 621 3o 9 2 3i62 323 1 33oi 33 7 i 3441 35u 358i 365r 3721 70 622 3790! 386o 3o3o 4027 4000 4070 4767 4139 420 9 4279 4349 5o45 44l8 70 623 4488 4558 4697 53 9 3 4836 4906 56o2 4976 5u5 70 624 5i85 5254 5324 5463 5532 5672 5741 58n 70 625 588o 5 9 4 9 6019 6 7 i3 6088 6i58 6227 62 9 7 6366 6436 65o5 °9 626 65 7 4 6644 6782 6852 6021 7614 6990 7060 7I2 9 7198 69 627 7268, 7337 7406 8098 7475 8167 8858 7545 8236 7683 83 7 4 7752 7821 78 9 o 69 628 7 9 6o| 8029 865i 8720 83o5 8443, 85 1 3 8582 69 629 8789 8 9 27 8 99 6 9065 9 i34' 9203 9 3 72 69 63o 799341 | 9400 O3002 9 | 0008 9478 9547 9616 9 685 9754 98231 9802 99° ' 69 63 1 0167 0236 o3o5 0373 0442 o5 n J o58o 0648 69 632 0717 O786 0854 0923 j 0992 1 061 1 1 29 n 9 8 1266 ■ 335 69 633 1404 1472 1 541 1609 1 1678 1747 i8j5 1884 I 9 52 2568 2637 2021 69 634 2089 2 1 58 2226 2295 2363 2432 25oo 2705 69 635 2774 2842 2910 35 9 4 29791 3o47 3n6 3 184 3252 3321 338o 68 636 3407 3525 3662 3730 3 79 8 386 7 4548 3o35 4&16 4oo3 407-1 68 637 638 4i3 9 4208 4276 4344! 4412 4480 46851 4 7 53 5365! 5433 68 4821 4889 4o57 563 7 5o25 5o 9 3 5i6i 5220 5 9 o8 52 9 7 68 63 9 55oi, 556 9 | 5705J 5773 584i 5 97 6 6o44| 6112 68 N. i 1 | 2 3 j 4 | 5 6 7 8 | 9 D A TADLE OF LOGARITHMS FROM 1 TO 10,000. 11 N. T40H 1 2 3 1 4 5 6 7 8 | 9 D. 806180 6248 63 16 6384 6431 6519 6587 6655 6723J 6790 68 641 6858 6926 6994 7061 7129 7197 7264 7332 7400 7467 68 642 7535 7603! 7670 8279 8346 7738 84>4 7806 8481 78 7 3 8549 7941 8616 8008 8076 8143 68 643 8211 8684 8751 8818 67 644 8886| 8o53 9021 9088 9 1 56. 9223 9290 9 358 9425 9492 F 645 9360' 9627 9694 9762 9829 9896 9964 ••3j ••98 •i65 67 646 8ios33, o3oo 0367 0434 o5oi 0569 o636 0703 0770 0837 i5o8 67 647 0904I 0971 iD75i 1642 1039 1 1 06 1 173 1240 1307 1374 1441 67 64S 1709 1776. i843 1910 ■977 2044 21 1 1 2178 67 649 2245! 23l2 2379 2445 25 1 2 ?5 79 2646 2713 2780 2847 67 65o 8l2gl3i 2980 3047 3 1 14 3i8i 3247 33i4 338 1 3448 35i4 &7 65i 3 58 1 1 3648 3714 3781 3848 39U 3 9 8i 4048 4114 4181 67 6J2 4248! 43 1 4 438 1 4447 45i4 458i 4647 47U 4780 ■4847 b J. 653 49 1 3 4o8o 5o46 5u3 f/75 5843 5246 53 1 2 5378 5445 55n 66 654 5578 5644 5711 5-777 5910 6573 5976 6042 . 6109 6i 7 5 66 655 6241 63o8 63 7 4 644o 65o6 663 9 670s 6 77 . 6838 66 656 6904 6970 7036 7102 7169, V o 3 l 73oi 8028 7433 '8094 7499 66 607 7365 8226 7631 8292 8961 8338 7764 8424 783o 7896 8'556 7962 8622 8160 66 658 8490 8688 8754 8820 66 65g 8885 9017 9083 9149 9215 9281 9346 9412 9478 66 660 8i9544 9610 9676 974i 9807 9873 ■9939 0595 1231 •••4 ••70 •i36 66 661 820201 0267 o333 0399 10O0 0464 o53o 0661 0727 0792 66 662 o858 0924 0989 1120 1 186 l3i7 1382 1448 66 663 i5i4 1 579 2233 1645 1710 I77 5 1841 I906 1972 2037 2103 65 664 2168 2299 2364 243o 2495 2360 2626 2691 2756 65' 665 2&22 -2887 2932 3oi8 3o83 ~3i48 32i3 3279 3344 3409 65 666 3474 3539 36o5 3670 3 7 35 38oo 3865 3930 3996 4061 65 667 668 4126 4191 4256 432i 4386 445 1 45i6 438i 4646 47 1 1 65 4776 4841 4906 4971 5o36 5ioi 5x66 523 1 5296 536i 65 669 5426 549 1 5556 5621 5686 575i 58i5 588o 5 9 45 65 9 3 6010 65 670 826075 6140 6204 6269 6334 6399 6464 6528 6658 65 671 6723 6787 6852 6917 6981 7046 7111 T75 7240 73o5 65 672 673 7 36g 8oi5 7434 8080 7499 8144 7363 8209 7628 8273 7692 8338 77^7 8402 7821 8467 7886 853 1 7961 85 9 5 65 64 674 8660 8724 8789 8853 8918 9361 8982 9046 9111 91^ 9^9 64 675 93o4 9 368 9442 9497 •U9 9625 9690 9754 9818 9882 64 676 9947 830089 ••11 ••75 •204 •268 •332 •396 •460 •525 64 %l o653 0717 i358 0781 o845 0909 i55o 0973 io3- 1 102 1 166 64 I23o 1294 2373 1422 •i486 1614 1678 1742 1806 64 679. 1870 1998 2637 2062 2126 2189 2828 2253 23 17 238i 2445 64 680 83 2309 2700 2764 2892 2956 302C 3i«S3 " 64 681 3 1 47 3211 3275 3338 3402 3466 353o 35o3 365- . 3721 64 682 3784 3848 3gl2 4548 3975 4039 4io3 4166 423c 429. 4357 64 683 4421 4484 461 1 4673 4739 4802 ' 4866 4925 5564 4993 64 684 5o56 5 120 5i8'3 5247 53 10 5373 5437' 55oc 5627 63 685 5691 6324 5754 58i7 588 1 5944 6007 607 1 | 6i34 619- 6261 63 686 6387 645i 65i4 6077 6641 6704 1 6767 683c 6894 63 687 688 8219 ' 7020 7o83 7146 7210 7273 7336 7J99 7462 ; 75a5 7967 8o3o! 8093 81 56 63 7652 8282 77i5 7778 7841 8471 7904 8334 63 689 8345 8408 85g7 866o| 8723 8786 63 690 838849 8912 8975 9 o38 9101 9164 9227 9289 1 9352' 94t5 63 691 9470 9341! 9604 9667 9729 9792 9855 9918 9981 » # 43 63 692 840106 O169' 0232 0294 o357 0420 0482 0345| 0608 0671 63 693 694 0733 ,35 9 1980 2609 0790! o85c 1422! 1485 0921 1 547 0984 1610 1046 1672 1 109 1735 1 172 1234 1297 I797 i860' IQ22 2422! 2484 23,47 63 63 1 693 2047I 2110 2172 2235 2297 236o 62 696 26721 2734 2796 2869' 2921 2 9 83 3046I 3io8 3170 62 697 698 32331 329s 1 3357 3420 3482 3544 36o6 3669I 3j3i. J79J 62 3855 3qi8! 3q8o 4042 4so4 4166 -4229' 4291 1 4J53 44i5 6a 699 4477 4339 | 4601 4664' 4726 4788 4850-4912 4974 5o36 62 1 2 3 | 4 | 5 6 | 7 U8 | 9 1 D. 12 A TABLE OF LOGARITHMS FROM I TO 10,000. «. I | 2 3 | 4 5 6 | 7 I 8 9 D. 700 845098 5l6o' 5222 5284 5346 5408 5470 5532 1 5594 5656 62 701 5718 5780' 5842 5904 5966 60281 6090 6131 62i3 6275 62 702 6337 6399 6461 6323 6585: 6646] 6708 6770 6832 6894 62 703 6o55 7017 7079 7141 7202 7264 7326 7388 8004 8620 7449 75ii| 62 8128 6z 8743 62 704 7o5 88o5 7634 8231 7696 83i2 7738 7819, 83-74 8435 8989 9031 7881 9497 It 8066 8682 706 8866 8928 91 1 2 9174 9788 9235 9297 9358! 61 707 708 85?o3? 9481 9042 9604 9665 9726 9849 9911 m 61 0095 oi56; 0217 0279 o34o 0401 0462 0324 6i 709 0646 0707 0769 o83o 0891 0932 1364 1014 1075 n36 1:97 61 710 85i258 1320 i38i 1442 i5o3 i625 1686 1747 2358 1809 6i 7" l8 l° 2480 19.3 1 2D4I 1992 2o53 2 1 14 2175 2236 2297 2419 61 712 2602 2663' 2724 2785 2846 2907 35i6 It* 3o2o 61 7.3 3090 3i5o 3211 3272, 3333 33 9 4 3455 4i85 3637 61 Vi 36g8 3759 3820 3881 3941 4349 4002 4o63 4124 4245 61 7 .5 43o6 4367 4428 4488 4610 4670 473i 4792 4852 61 716 4oi3 5519 4974 5o34 5095 5i56 52i6 5277 5337 53 9 8 5459 61 717 718 558o 564o 6701 5761 5822 5882 5943 6548 6oo3 6064 61 6124 6i85 6245 63o6 6366 6427 6487 6608 6668 6o- 719 6729 6789 73 9 3 685o 6910 7 5i3 6070 7374 7o3i 7091 702 7212 7272 60 720 857332 7453 7634 7694 8357 8958 78i5 8417 9018 •7875 &t77 60 721 It 9 ,38 7995 8o56 8116 8176 ■ 8236 8297 60 722 85 9 7 9198 865 7 8718 8778 8838 8898 9078 60 723 9258 9318 9379 9439 9499 $8 9619 •218 9679 60 724 8blht 9799 0398 9 85 5 9918 9978 ••38 ••98 •278 60 725 0458 0318 0378 0637 0697 0757 0817 0877 60 726 0937 0996 io56 1116 u 7 6 1236 1293 i355 Ui5 U75 60 727 728 1 534 1394 1634 1714 i 77 3 1 833 i8 9 3 2489 1932 2349 2012 2072 60 2l3l 2191 2787 225l 23 10 2370 243o 2608 2668 60 729 2728 863323 2847 2906 2966 356i 3o25 3o83 3i44 3204 3263 60 73o 3382 3442 3301 3620 368o 3 7 3o 4333 3 799 3858 5, 731 3917 3977 4o36 4096 4i55 4214 42 -i 4392 4452 5 9 732 4DII 4570 463o 4689 4748 4808 4867 4926 55i 9 4985 5o45 59 733 5io4 5i63 5222 5282 5341 5400 5459 5578 5637 5 9 734 56 9 6 5755 58i4 5874 5g33 6324 5992 6583 6o5i 6110 6169 62,8 5 9 735 6287 6878 6346 64o5 6463 6642 6701 .6760 6819 5 9 736 6 § 37 8174 7055 7114 7173 7232 7880 8468 ''735o 7409 £9 $" 7467 8o56 7526 8n5 7644 7703 8233 8292 7762 835o 7821 8409 » 3 ° 8327 9 5 9 739 8644 8703 8762 88211 8870 9408, 9466 8o38 8997 9036 9ii4 9173 5 9 740 ' 869232 9290 9349 9935 9525 9384 9642 9701 9760 59 741 9818 9877 9994 "53 •111 • 170 •228 •287 •345 5g og3o| 58 742 870404 0462 0321 0379 o63£ 0696 0755 o8i3 0872 743 098c 1047 1 106 U64 1223 1 281 1 339 1920 i3o8 1456 13l5 58 744 i5 7 3 i63i 1690 1748 1806 1 865 1981 2040 2098 2681 58 745 2i 56 22 1 5 2273 2855 233 1 2389 2448 23o6 2364 2622 58 746 2739 2797 2913 2972 3o3o 3o88 3i46 3204 3262 58 74 Z 748 332 1 i 3379 3437 3495J 3553 36u| 3669 2727 3785 3844 58 3 9 02 3o6o; 4018 4076, 4i34 4192 4230 43o8 4366 4424 58 749 4482 4540! 4598 4656' 47U 4772 483o 4888 4945 5324 5oo3 58 75o 875061 5iio' 5177 5698 5756 5235; 5293 535 1 j 5409 5466 5582 58 7 5i 5640 58i3| 5871 5929 5987 6o45 6102 6160 58 lit 6218 6276! 6333 639^ 6449' 65°7 6564 6622 6680 6737 58 753 6793 6853 6910 6968J 7026 70S3, 7141 7199 7256 7314 58 754 7371 7429' 7487 8oo4| 8062 7644J 76021 7659 1 7717 8119 1 8177! 8234-1 8292 8349 7832 7889 8464 58 755 7947 8322 8407 57 756 8079' 8637 8694 8i52 8809 8866 9325 9383 9440 8924 8981 9o3q 57 $ 9096. 9153, 921 1 9268 9497 9555 9612 57 9669 9726 9784 9841 9898 9936 »»i3 ••70 •127 •i85 57 7 5 9 880242 0299 o356, o4i3; 0471 0028 o585 0642 0699 0756 57 N. 1 I | 2 j 3 4 |- 5 | 6 7 8 9 r>. TABLE OP LOGARITHMS FROM 1 TO 10,000 13 N. 760' 761 762 763 764 763 766 1 b l 768 769 770 77' 772 773 .774 775 776 777 778 779 780 V£ l 782 783 784 785 786 787 788 789 790 79' 792 7 9 3 794 7 9 5 796 797 798 799 800 801 802 8o3 804 8o5 806 807 808 809 810 811 812 8i3 814 8i5 816 Sl l 818 819 • N. 880814 1 385 io55 2325 3093 3661 4229 479S 536i 5926 886491 7034 7617 8179 8741 9S02 9862 890421 0980 i53t 892095 ?65 1 3207 3762 43 16 4870 5423 5g75 6526 7077 S97627 8176 8725 9273 9821 900367 0913 U58 2003 2547 903090 3633 4n4 4716 5256 5796 6335 6874 74' 7949 0871 1442 2012! 2061 358 1 1 203i 3i5o| 3207 3718, 3775 42851 4342 4852 4909 54i8 5o83 6547 7111 7674 8236 87. 93: 9918 io35 i5o3 2 1 DO 2707 3262 3817 4371 4 9 25 5478 6o3o 658i 7i32 7682 823i 8780 9328 9 8 7 5 0422 0968 I3l3 2057 2601 3i44 3687 4229 477° 53io 585o 6389 6927 7465 0928' 0985 1499I '556 2126 269a 3264 3832 4399 496a 553i 6096 6660 7223 B r 8909 9470 ••3o 0689 1147 i7o5 2262 5474 6039 6604 7167 773o 8292 8853 94U 9974 o533 1091 1649 2206 2762 33 " 3873 4427 49S0 5533 6o85 6636 7187 7737 8286 8835 9 383 9930 0476 1022 1 56 7 2112 2655 3199 3 7 4i 4283 4824 5364 5904 6443 698 1 7019 4 3 9021 9556 9IOO9I 0624 n58 1690 2222 -' 2753 3a84 8002 1 8o56 853g] 8592 9074 9128 9610 9663 0144 0197 0678 0731 1211 1 264 1743 1797 227D 2J28 2806 285g 33371 3390 3373 3928 4482 5o36 5588 6140 6692 7242 lit 8890 9437 9g85 o53i 1077 1622 2166 2710 ■ 3253 3 7g 5 4337 4878 5418 5 9 58 6497 7 o35 75 7 3 8110 8646 9181 97 16 025i 078: i3i7 i85o 238i 2913 3443 1042 i6i3 2183 27P2 3321 3888 4455 30.22 5587 6i52 6716 7280 7842 8404 8n65 9626 ••86 0645 1203 1760 2317 2873 3429 3984 4538 509 1 5644 6195 6747 7297 7847 83 9 6 89. 94 ••39 o586 ii3i 1676 2221 2764 3307 3849 4391 4932 5472 6012 655i 7089 7626 8i63 8699 9233 9770 o3o4 o838 1371 1903 2435 2066 3496 1099 1670 2,240 2809 33 77 3g43 4512 5078 5644 6209 6p3 7 336 8460 9021 9582 •141 0700 I25g 1816 23 7 3 2929 3484 4039 45 9 3 5U6 5699 625 6802 7352 7902 845 1 8999 g547 ••g4 0640 1 186 , 7 3. 227D 2818 336 3904 4445 4986 5326 6066 6604 7143 7680 8217 8753 u56 1727 2297 2866 3434 4002 4569 5i3d 5700 6265 6829 7392 Itl 9"77 9 038 •'97 0756 i3i4 1872 24:9 2980 3d 40 4094 4648. 5201 57D4 63o6 6807 7407 79 5 .7 85o6 905 9602 •140 069D 1240 i 7 85 2320 I2i3 1271 I784] l84I 2354 ! 241 1 2923. 2980 3491 3D48 40D9 41 15 4625 4682 5192 57D7 6321 6885 7449 801 1 8273 9134 9694 •233 0812 i3 7 o 1928 2484 3o4o 35o5 4i5o 470. 525 7 58og 636i 6912 7462 8012 856i 9109 9 656 •2o3 0741 129 1840 2384 9 "l328 D. 28731 2927 3416 3470 3968 1 4012 4499: 4553 5o4o! 0094 558o. 5634 6119! 6173 6658| 6712 7196I 7250 7734, 7787 8270I 832 88oti 8860 9289] 93421 9396 9823; 9877J 9930 o358 0891 1424 1936 2488 3019 3549 5248 58i3 6378 6942 73o5 8067 8629 9190 9730 •3oi 086 1421 1983 2340 3096 36di 42o5 4759 53l2 5864 6416 6967 I, 1 8067 86i5 9164 WW •258 0804 1 349 1894 2438 2981 3324 4066 460 5i* 5688 6227 6766 73o4 f 8378 89U 9449 998 o5i 041 1, 0464 1 0944 0998 io5i 1477] ' 53 °! ,58 4 2009' 2o63 2341 3072 3602 2594 3i25 3655 2468 3o37 36o5 4172 Hoi 5870 6434 6998 7561 8n3 8685 .9246 9806 •365 0924 1482 2039 2593 3i5] 3706 4261 4614 5367 5920 6471 7022 7572 8122 8670 9218 9766 •3l2 0859 1404 1948 2492 3o36 3578 4120 4661 5202 5742 6281 6820 7358 7895 #43 1 8967 9303 ••37 0571 1 104 1637 2169 2700 323i 2116 2647 3178 3708 3761 5i 57 5 , T « 7 l 1 ll 56 56 56 56 56 56 56 56 56 56 56 56 56 55 55 55 55 55 55 55 55 55 55 55 55 55 55 54 54 54 54 54 54 54 54 54- 54 54 54 54 54 54 53 53 53 53 53 53 53 53 D- 14 A TABLE OF LOGARITHMS FROM 1 TO 10,000. N. 82Q . | 2 j 3 | 4 | 5 6 j 7 8 9 D. 9i38i4 3867J 3920 3973 4026, 4079 4i3a| 4184 42371 4290 53 821 4343 4396 4449! 4302 4555 4608 4660! 471.3 4766; 4819 '3 822 ,4872 4925 49771 5o3o 5o83' 5i36 6189' 5241 5294 5347 53 823 5400 5453 55o5| 5558 56n! 5664 57161 5769 5822 5875 53 824 5927 5980 6o33 6o85 61 38 6191 6243 6296 6349 64° ' 53 823 6434 65o7 655c, 6612 6664 67 1 7 6770 6822 68731 6927 53 826 6980 7033 708: 7i38 7190 7243 7295 7348 7400 1 7453 53 8 n 828 > 7D06 8o3o 7D08 7611 8o83 8i35 7663 8188 7716 7768 7820 78 7 3 .8397 7925 7978 845o! 85o2 52 8240 8293 8345 52 829 8555 8607 865c 9i3o 918J 8712 8764 8816 8869 8921 89735 9026 52 83o 919078 9235 9287, 9340 9 3 9 2 9444 9496 j 9549 52 83 1 0601 926*123 9653 9706 9738 98 1 o, 9862 9914 9967 ••19 "71 52 832 0176, 0226 0280 o332' o384 ■0436 0489 o54i OD93 52 833 o645 0697! 0749 1218J 1270 0801 o853, 0906 0908 1010 1062 1114 52 834 1166 1322 1374! 1426 1478 l53o i58a 1634 52 835 1686 I738j 1790 1842 1894 1946 1998 2o5o 2102 21 54 52 836 2206 2258, 23 [0 2362 2414 2466 23 18 2570 2622 2674 52 83t 838 272D 2777 2829 2881 2933 2985 3o37 3o8g 3 1 40 3192 52 3244 32g6 ! 3348 3399 345 1 35o3 3555 3607 3658 3710 52 839 3;62 38i4' 3865 3917 3969 4021 4072 4124 4176 4228 52 8jo 924279 433i, 4383 4434 4486 4538 4589 ■464i 4693 4744 52 841 4796 4848 4S09 49)1 5oo3 5o54 5 1 06 5i57 5209 6261 52 842 53i2 5364 54i 5 5467 55i8 5570 1 5621 5673 5723, 5776 52 8 ',3 5328 5S79 593 1 5982 6o34 6o85j 6i37; 6188 6240! 6201 5! 844 6342 6394 6445 6497 6548 6600! 665 1 j 6702 6 7 54 68o5 5i 845 6357 6908 6959 7422' 7473 701 1 7062 71 14 7i65, 7216 7268 73i9 5i 846 73 7 o 7524 8o3; 7576, 7627 8088 8140 7678, 7 7 3o 91911 8242 8703J 8754 7781 8293 7832 8345 5i 847 848 7883 7, r. •;,/-,, 5i 8396 8447 8498 8549 8601 8652 88o5 885 7 5i 849 8908 8959 9010 9061 9112 9163 9.2 1 5| 9266 9317 9 368 5i 85o 929419 9470 9521 9572 ••83 9623 9674 •i34 °i85 9725j 9776 •236, 0287 9827 9879 •38 9 5i 85i 99 3o 9981 »">32 •338 5! 852 900440 0491 0542 0592 0643 0694 0745, 0796 0847 0898 5i 853 0949 1000 io5i 1102 1 1 53 1204 1254 1 i3o5 1356 1407 5i 854 1458 1 609 i56o 1610 1661 1712 I763i 1814 1 865 1915 5i 855 1966 2017 2068 2118 2169 2220 227I 2jB2 2372 2423 5i 856 2474 2524 2575 2626 2677 2727 27781 282g 2S79 2930 5i 807 858 2981 3o3i : 3o'-i2 3i33 3i83 3234 3285 3335 3386 3437 5i Mil 35381 3589 363 9 3690 3740 379' 3841 38 9 2 3 9 43 5i 8J9 3993 4044 4094 4i45 4195 4246 4296 4347 4397 4448 5i 860 934498 4049' 4599 465o 4700 475 1 4801 4852 4902 4953 5o 861 5oo3 5o54 5 1 04 5 1 54 52o5 5255 53 06 5356 54o6 5437 5o 862 5507 5558, 56o8 5658 5709 5759 5809 586o 5910 6960 5o 863 601 1 6061 ' 61 1 1 6162 6212 6262 63i3j 6363 64i3 6463 5o 864 65 14 6564! 66U 6665 6715, 6765 68i5 6865 6916 6966 5o 865 7016 7066' 7117 7568. 7618 8069 1 81 19 7167 7217 7267 7317 7367 74i8 7468 5o 866 7518 8019 7668 8169 77181 7769 7819 7869 7919 7969 5o 867 868 8219' 8269 8320 8370 8420; 8470 5o 8520 8570, 8620 8670 8720J 8770 8820 8870 8920 8970 5o 869 9020 9070! 9120 9170 9220 9270 9320 9369 9419 9918 9460 5o 870 939519 9569 1 9619 9669 9719 1 9769 9819 9869 9968 5o 871 940018 0068 0110 0168 0218; 0267 o3i7 0)67 0417 0467 5o 872 o5i6 o566 0616 0666 07i6i 0760 081 5 o865 0915 0964 5o 873 1014 1064! mj 1 [63 I2i3| 1263 l3i3 1 362 1412 1462 5o 874 i5i i i56i| 161 1 , 1660 1710! 1760 1809 1839 1909 1958 5o 87 a 200S, 20381 2107 2157 2653 2207I 2256 23o6 2355 2403 2455 5o 876 25o4J 2554 26o3 2702: 2762 2801 285 1 2901 2o5o 5o 87? 879 3oooj 3040: 3oq9 3148 3198' 3247 3297 ■ 3346 33 9 6 3445 5 9 34g5| 3544, 35o3 3643 3989 4o38 4oH8| 4i3-> 36o2 3742 4186 4236 3 7 oi 428a 3841 4335 38 9 o 4384 3939 4433 5 9 If. | 1 j 2' . 3 |-4 | 5 i 7 8 9 D. A TABLE OF LOGARITHMS FUOM 1 TO 10,000. 15 N. I a 3 1 4 | 5 | 6 | 7 8 9 D. 880 944483 4532 458 1 463 1 1 4680! 4729I 4779! 4828: 4877J 4927 49 881 4976 5o25 D074 5i24l 5i73i 5222, 5272; 532i' 5370: 54iQ 49 882 5469 55i8 5567 56i6 5665 1 '5 7 i5j 5764 58i3 6108; 6157! 6207 6256: 63o5 6600! 6649' 6698! 6747! 6796 5862 5912 49 883 5961 6010 6059 6354 64o3 49 884 6452 65oi 655i 6845 6894 49 885 6943 6992 7483 7041 7090J 7140, 7189J 7238 7287 7336 : 7385 49 886 7434 7532 8022 758i 763oj 7679, 7728 7777 7826 7875 49 887 888 7924 7973 8070' 81 19 1 8168 8217 8266, 83 1 5 8364 49 84i3 8462 85 n 856o; 8609 8657 8706 8 7 55 8804 8853 49 889 8902 949J90 8931 8999 9048; -9097 9146 9 rn5 9 683 9244 1 9292 g34i 49 890 9439 9488 9536 9583 9634 973 1 9780 9829 49 891 9S78 9926 9975 ••24 ••73 •121 • 170 •219 •267 •3 16 49 892 9Do365 0414 0462 o5u o56o 0608 06D7 0706 0754 o8o3 49 89J o85i 0900 0949 0997 1483 1046 1095 1143 it 92 1240 1289 1773 49 894 1338 1386 i43o 1532 1 58o 1629 1677 1726 4o 895 1823 1872 1920 1969 2017 2066' 21 14 2i63 2211 2260 48 896 23o8 2356 24o5 2453 25o2 255o 2599 2647 2696 2744 48 ! 9 2 2792 2841 28S9 lo38 2986 3o34 3o83 3i3i 3i8o 3228 48 898 3276 3323 3373 342 1 3470 35i8 3566 36 1 5 3663 3711 48 899 3760 3808 3856 3905 3 9 53 4001 4049 4098 4146 4194 48 900 954243 4291 4339 438 7 4435 4484 4532 458o 4628 4677 5i58 48 901 4725 4773 4821 4S69 4918 4966 5oi4 6062 5iio 48 902 5207 5255 53o3 535i 5399 58So 5447 5928 5495 5543 5592 5640 48 903 5688 5736 5 7 84 5832 5976 6024 6072 6120 48 904 6168 6216 6265 63i3 636i 6409 6457 65o5 6553 6601 48 905 6649 6697 6745 6793 6840 6SS8 6 9 36 6984 7032 7080 48 906 7128 7176 7224 7272 7320 7368 7416 7464 7512 7559 8o33 48 ■907 .. 908 7607 8086 7655 7703 8181 775i 7799 7847 8325 7894 7942 8421 7990 48 8i34 82*9 8277 8373 8468 85i6 - 48 9"9 8564 8612 865g 8707 8 7 55 88o3 885o 8898 8946 8994 48 910 959041 9089 9 l3 7 9 i85 9232 9280 9328 9 3 7 5 9423 94T 48. 9 u 95i8 9 566 9614 9661 97°9 97 5 7 9804 Q 852 9900 9947 48 912 9995 ••42 " a qo •i38 •180 •233 •280 •328 •376 •423 . 48 913 96047 1 o5i8 o566 o6i3 o66t 0709 0756 0804 0831 0899 48 914 0946 0994 1041 1089 1 563 "n36 1 184 1 23 1 1279 1753 i326 1374 47 9i5 1421 1469 1943 i5i6 1611 i658 1706 1801 1848 47 916 i8 9 5 1990 2o38 2o85. 2l32 21S0 2227 2275 2322 47 917 918 2 l b 9 2417 2464 25ll 255g 2606 2653 2701 2748 2795 Al \ 284J 2890 2937 2985 3o32 3079 3i26 3i74 3221 3268 47 919 33i6 3363 34io 3457 3 304 3552 3599 3646 36 9 3 3741 47 920 963788 3835 3882 3929 3977 4024 4071 4118 4i65 4212 47 921 4260 4307 4354 4401 4448 4495 4542 4590 4637 4634 47 922 473i 4778 4825 4872 4919 4966 5oi3 5o6i 5io8 5i55 47 923 5202 5249 5296 5343 5390 5S6o 543 7 6484 553 1 55 7 8 5623 47 924 5672 5719 5 7 66 58i3 5907 5954 6001 6048 6095 4,7 923 6l42 6189 6236 6283 6329 63 7 6 6423 6470 65i 7 6564 47 926 66l I 6658 6705 6752 6799 6845 6892 6939 6986 7o33 47 927 7080 7127 7173 7220 7267 73i4 736i 7408 7454 75oi 47 .928 7548 7595 7642 8109 7688 8i56 P 3 2 8203 7782 7829 7875 7922 ,83 9 o 7969 47 9 2 9 8016 8062 8249 8296 8343 8436 47 9J0 968483 853o 85 7 6 8623 8670 8716 8 7 63 8810 8836 8903 9369 47 931 8 9 5o 8996 9043 9090 9i36 9i83 9229 9276 9 323 47 932 9416 9463 9009 9336 9602 9649 9695 9742 9789 9 S35 47 933 9882 9928 9973 ••21 ••68 •114 •161 •207 •254 •3oo 47 934 970347 o3g3 0440 0486 o533 0379 0626 0672 0719 0765 46 9 35 0S12 0808 0904 1369 0951 0997 1044 1090 u3 7 n83 1229 46 936 1276 1322 I4i5 1461 i5o8 1534 1601 1647 i6g3 2137 46 III 1740 ' 17S6 i832 1879 I 9 2 S 1 971 201!: 2064 :iio 46 2203 2249 2295 2342 2388 2434 248t 2527 2373 26'9 46 9 3 9 2666 2712 2738 2804 285i 2897 294J 2989 3o35i 3o82 46 K. • 1 2 3 4 5 1 6 7 8 | 9 D. 21 ■■ 6 A TABLE OF LOGAltlTHMS FROM 1 TO 10,000. N. 1 2 3 4 | 5 6 7 8 9 D. 940 973128 3i74 3220 3266 33i3| 3359 34o5 345 1 3497 3o5o 3543 46 94i 35oo 4o5i 3636 3682 3728 3774I 3820 3866 3oi3 4374 4oo5 46 942 4.097 4558 4U3 4189 4235| 4281 4327 4788 4420 4466 46 943 45i2 4604 465o 4696 4742 4834 4880 4926 5386 46 944 4972 5oi8 5064 5iio 5n6 5202 5248 5294 5753 5340 46 945 5432 5478 5524 5570 56i6 5662 5707 5799 5845 46 946 5891 635o 6854 5983 6029 6075 6121 6167 6625 6212 6258 6304 46 947 948 6442 6488 6533 6579 6671 6717 6 7 63 46 6808 6900 6946 6992 7037 7o83 7129 7175 7220 46. 949 7266 7 3l2 7358 74o3 7449 7495 7541 7586 8043 7632 8089 7678 8i35 46 9_5o 977724 81 Si 7769 8226 7 8i5 8272 7861 7906 7952 7998 46 931 83i 7 8363, 8409 8454 85oo 8546 85 9 i 46 952 863t 9093 8683 8728 8774 8819 1 8865 927D 9321 8911 8 9 56 9002 9047 46 9 53 9i38 9184 9230 9366 9412 9457 95o3 46 9 54 9548 9394 9639 9 685 97 3 °' 9776 9821 9867 99 ! 2 9953 46 9 55 980003 0049 o5o3 0094 0140 oi85 o23i 0276 0730 0322 0367 0412 45 9 56 0458 o549 0594 0640! o6S5 O776 0821 0867 45 lU 0912 1 366 0957 1 oo 3 1048 1093: 1 1 39 1184 I229 1275 1320 45 1411 1456 i5oi . i547 1692 1637 i6S3! 1728 i 77 3 45 9 5 9 1819 1864 1909 1954 2000, 2045 2090 2i35 2181 2226 45 960 982271 23i6 2362 2407 2402 1 2497 2543, 2588 2633 2678 45 961 2723 2769 2814! 2839 2904 2949 2994 3 040 3o85 3i3o 45 962 3i75 3220 3265i 33io 3716 3762 4167! 4212 3356 34oi 3446 3491 3536 358i 45 9 63 3626 36 7 i 3807 3852 38 97 3o42 4J92 3987 4o32 45 964 4077 4122 4257 4302 4347 4437 4482 45 9 65 4527 4572 4617 4662 4707 4752 4797 4842 4887 4932 45 966 4977 3022 5067 5lI2 5i5 7 56o6 5202 5247 5292 5337 5 7 86 5382 45 967 968 5426 5471 55i6 556i 565 1 56 9 6 574. 583o 45 58 7 5 5920 636 9 5965 6010 6o55 6100 6144 6189 6234 6279 45 969 6324 64i3 6458 65o3 6548 65 9 3 6637 6682 6727 7175 45 , 97° .986772 6817 6861 6906 7353 6951 7 3 9 8 6996 7040 7o85 7i3o 45 1 97' 7219 7264 7 3o 9 7443 7488 7532 7577 8024 8470 7622 8068 85i4 45 97? 973 7666 8u3 VI 1 8i5 7 77^6 8202 7800 8247 7845 8291 87J7 83^6 lt\ lilt 43 45 974 855o 9003 8604 8648 8693 9i38 8782 8826 8871 8916 9361 8960 45 97 5 9049 9094 9 53o gi83 9227 9272 93i6 94o5 45 976 g45o 9404 993o o3b3 9 583 9628 9672 97'7 9761 9S06 985o 44 977 978 9895 9983 ••28 ••72 •117 •161 •206 •25o •294 07J8 44 990339 0428 0472 o5i6 o56i o6o5 o65o 0694 1137 44 979 o 7 83 0827 0871 0916 1309 0960 1004 1049 1093 i536 1 182 44 980 991226 1270 i3i5 i4o3 1448 1492 io35 2377 i58o 1625 44 981 1669 1713 1758 1802 1846 1890 2333 '979 2023 2067 44 '2? 21 11 2i56 2200 2244 2288 2421 2465 25og 44 983 2554 25o8 3o39 2642 2686 2730 2774 2819 2863 2907 2q5i 3J92 3833 44 984 2995 3436 3o83 3127 3568 3172 ' 32i6 326o 33o4 3348 44 '^ 3480 3524 36i3 365 7 3701 3745 3 7 8 9 44 986 3877 3921 436 1 3965 4009 4o53 4097 4537 4Ui 4i85 4229 4273 44 ? 43i7 44o5 4449 4493 458 1 4625 4669 5io8 47'3 44 5io6 995635 4801 4845 4889 4933 53 7 2 4977 5021 5o65 5i52 44 989 5240 5284 5328 5416 5460 55o4 5547 5 9 86 55of 6o3o 44 991 K79 5723 5767 58n 5854 58 9 8 6337 5 9 42 638o 44 991 6074 6„ 7 6161 6205 6249 6293 6 7 3i 6424 6468 44 992 65i2 6555 65o 9 6993, 7037 743o 7474 6643 6687 '6774 6818 6862 6906 7343 44 99 3 6949 7386 7080 7124 7168 7212 7255 7299 7736 8172 44 994 7517 7 56i 76o5 8041 7648 7692 8129 7779 8216 44 99? 7823 8259 86o5 91J1 7867! 7910 83o3, 8347 8390 7998 8434 8o85 44 996 8477 8521 8564 8608 8652 44 997 8 7 3 9 ' 8782 8826 8869 8 9 i3 8o56 9392 9000 ■9043 9087 44 998 9174' 9218 9261 93oo| 9348 9435 9479 0522 44 999 N. 9565 9609 9652 ' 9696 _ 3~ 9739 i 9783 9826 9870 _99i3 8 9957 43 I 2 5 6 7 9 ! D„ A TABLE oir LOGAKITHMIC SINES AND TANGENTS FOB EVERY DEGREE AND MINUTE OF THE QUADEANT. REMARK. The minutes in the left-hand column of each page, increasing downwards, belong to the de- grees at the top ; and those increasing upwards, in the right-hand column, belong to the degrees below. 18 (0 DEGREES.) A TABU OF IOGARITHMIO M. Sine 0' 000000 ]>. Cosine D. Tang. 1). Cptang. 1 ' 10- 000000 ■ onoooo Infinite. 60 I 6-463726 5017.17 000000 • 00 6-463726 5017 S3 7 i3 536274 235244 tl a 764736^ 2934 85 000000 • 00 764706 . 2934 3 940847 2082 3i 000000 ■ 00 940847 2082 3i o59i53 57 4 7065786. i6i5 u 000000 • 00 7.060786 i6i5 .'7 !2-o342i4 56 5 162696 1319 000000 • 00 162696 1319 69 837304 758122 55 6 241877 in5 75 9.999999 .0. 24187.8 HID i 54 54 I 308824 3668i6 966 852 53 54 999999 999999 • 01 •0! 3o8825 366817 852 691 175 633 1 83 53 52 9 - 417968 762 63 999999 •01 417970 762 63 582o3o' 5i 10 463725 689 88 999998 ■01 . 463727 689 88 536273! 5o 12-494880; 49 407091: 40 ii 7-5otyi8 629 81 9-999998 •01 7-5o5i20 629 81 12 542906 579 36 999997 •01 542909 5 79 33 i3 577668 536 41 999997 •01 577672 536 42 422328 s U 6og853 499 38 999996 '01 609857 499 3o 3ooi43 i5 639816 467 438 14 999996 •01 639820 467 438 13 36oi8o 45 16 667845 81 999995 ■01 667849 82 332i5i 44 12 694173 4i3 72 99999 s ■01 694179 4i3 73 3o582i 43 718997 391 35 999994 •01 719004 3gi 36 280997: 42 19 742477 3 7 i 27 999993 ■01 742484 3 7 i 28 257516! 41 20 764754 353 i5 999993 •01 764761 35i 36 235239! 40 21 7 -785 9 43 806146 336 7 2 9-999992 •01 7-785951 8061 55 336 73 12 •214049! 39 22' 321 75 999991 •01 321 76 I93845J 38 23 82545i 3o8 o5 99999° •01 820460 3o8 06 I74540I 37 i56o56] 36 24 843934 •295 283 u 999989 •02 843944 295 283 49 25 861662 999988 •02 861674 90 i38326i 35 26 8786951 273 17 999988 •02 878708 2 7 3 18 121292 34 -3 890085 263 23 999987 •02 895099 263 25 1 0490 1 33 910879 .253 $ 999986 •02 910894 926134 254 01 089106 073866 32 29 9261 19 . 245 999985 •02 245 40 3i 3o 940842 237 33 999983 ■02 94o858 23 7 35 069142 3o 3i 7-955082 229 80 9-999982 •02 7'955ioo 229 81 12-044900 29 32 968870 982233 222 73 ■ 9999 81 ■02 968889 982253 222 75 o3 1 1 1 1 28 33 216 08 999980 •02 216 10 017747 2 34 995198 209 20J 81 999979 •02 995219 209 203 83 004781 .35, 8-007787 90 999977 ■02 8-007809 020045 n n-992101 979955 2D 36 020021 198 3i 999976 ■02 198 24 u 031919 043601 i 9 3 02 999975 ■02 o3io45 043027 1 93 o5 968055 23 188 01 999973 •02 188 o3 956473 22 3 9 054781 1 83 25 999972 ■02 054809 o65Ko6 i«3 27 945191 21 40 065776 178 72 99997' ■02 178 74 934194 20 41 8-076500 086965 174 41 9-999969 ■02 8-07653i 174 44 11-923469 9>3oo3 3 42 170 166 3i 9999°° ■02 086997 170 34 43 097183 3 9 999966 •02 097217 166 42 , 902783 n 44 107167 1 16926 162 65 999964 •o3 107202 162 68 fe 7 2 7 883o37 16 45 1 5 9 08 999963 ■ o3 116963 126310 1 5 9 10 i5 46 126471 i55 66 999961 ■o3 155 68 873490 14 % i358io 1 52 38 999; 5o ■o3 i3585i 1 52 41 864149 i3 144953 149 24 999958 •o3 144996 149 27 855oo4 12 i 9 153907 146- 22 999956 • o3 1539:12 146 27 846048 11 5o 162681 143 33 999954 • o3 1627:17 8-171328 143 36 837273 11 828672 10 5i 8-171280 140 54 9-999952 ■o3 140 67 1 52 179713 i3 7 86 99995o • o3 179763 i88o36 137-90 135-32 820237 53 187985 135 29 999948 • o3 81 1964 I 54 196102 132 80 999946 • o3 196156 132-84 8o3844 55 204070 l3o 41 999944 • o3 204126 i3o-44 7o58 7 4 5 56 2ii8o5 219581 128 10 999942 • 04 21 1953 128-14 788047 4 n 125 8 7 999940 • 04 219641 125-90 78o35o 3 227134 123 72 999938 ■ 04 227195 123-76 121-68 772803 765379 2 5 9 234557 121 64 999936 ■04 234621 1 6o 24i855 1 1 9 • 63 999934 • 04 241921 119-67 758079 ( Cosine D. Sine 89° Cotang. D. - Tang. M. SINES AND TANGENTS. (1 DEQREE.) l'b M. Sine i D. \ Cosine IX. | Tang. | D. Cotang. 1 3-24i855 119-63 9-999934 •04 8-241921 119-67 11-758079 60 i 249033 117-68 999932 .04! 249102 117-72 760898 11 3 256094 u5-8o 999929 ■04j 256i65 HD-84 743835 3 263042 n3-g8 999927 ■04 263n5 114-02 736885 iz 4 269881 112-21 999925 -04, 269906 112-20 730044 5 2766I4I IIO-5o 999922 •04 1 276691 UO-54 723309 55 6 283243 io8-83 999920 ■04 283323 108-87 716677 54 I 289773 107-21 999918 ■o4j 289866 107-26 710144 53 290207 io5-65 999910 •.04' 296292 105.70 703708 697366 52 9 302046. 104- i3 999913 •04 302634 io4- 18 5i 10 308794 102-66 999910 -04) 3o8884 102-70 691 1 16 5o ii 8-3i49o4 101 - fj 9-999907 •04 8-3i5o46 101-26 11-684954 678878 ■672886 % 12 321027 90-82 98-47 999905 •04 32112 2 99.87 13 327016 999902 .04 327114 98 -5i 47 U 332924 97-14 999899 ■o5 333o25 97-19 666975 46 i5 338753 g5-86 999897 -o5 338856 95.90 661 144 45- 16 344504 94-60 999894 • o5 344610 94-65 655390 44 \l 35oi8i 9 3 -38 999891 ■o5 350289 355895 36i43o 9 3-43 6497 1 ! 43 355783 92-19 91 -o3 89-90 88- 80 999888 ■o5 92-24 644 1 o5 42 ■9 36i3i5 999885 -o5 91-08 638570 41 20 366777 999882 •o5 3'668 9 5 88* ■ $5 633io5 40 21 8-372171 9-999879 •o5 8-372292 11-627708 622378 ll 22 377499 382762 87-72 999876 ■o5 377622 382889 87-77 23 86-67 . 999873 • o5 86-72 617111 37 24 38796a 39J101 85-64 999870 •o5 388oo2 3932J4 .85-70 611908 36 25 84-64 999867 ■o5 84-70 606766 35 26 398179 83-66 999864 -o5 3 9 83i5 83-71 601685 34 2 403199 82-71 999861 -o5 4o3338 82-76 81-82 596662 33 408161 80 -ll 999858 •o5 4o83o4 691696 5867B7 32 2 9 4i3o68 999854 •o5 4i32i3 80-91 3i 3o 417919 79-96 999851 -06 418068 80 -02 58-1 9 32 3o ' 3i 8-422717 ]n 9.999848 • 06 8-422869 79-14 n-577i3f 3 32 427462 999844 .06 427618 78.30 572382 33 432i56 77-40 999841 •06 4323 i5 77-45 56 7 685 2 7 34 4368oo 76-57 999838 •06 436n62 44i56o 76-63 563o38 26 35 44i394 73-77 999834 .06 75-83 558440 25 36- 445941 74-99 999831 ■06 4461 10 7 5. o5 553850 549387 24 ll 45o44o 74-22 999827 ■06 45o6i3 74-28 23 454893 73.46 999823 .06 455070 459481 73-52 544o3o 540619 22 3 9 459301 463665 72-73 999820 ■06 72-79 21 4o 72-00 999816 • 06 463849 72-06 536i5i 20 41 8-467985 71-29 9-999812 ■ 06 8-468172 71-35 n-53i828 \l 42 472263 70-60 999809 999805 ■ 06 472454 .70-66 527546 43 476498 480693 69-91 ■ 06 476693 480892 69-98 523307 519108 'I 44 69-24 999801 .06 69-31 68-65 l6 45 484848 68 -5g 999797 .07 485o5o 5i4o5o 5io83o i5 46 488963 67.94 67-31 66-69 66- 08 999793 .07 489170 68-01 14 47 493040 999790 .07 49J 2 Do 67-38 506750 i3 48 497078 5oio8o 999786 .07 497293 66-76 502707 12 49 999782 ■ 07 501298 66-i5 498702 11 5o 5o5o45 65-48 999778 ■07 5o5267 65-55 494733 10 5i 8-508974 512867 516726 64-89 9-999774 .07 8 - 509200 64-96 11-490800 9 52 64-3i 999769 .07 513098 64-39 486902 8 53 63-75 999765 .07 5 1 696 1 63-82 483o39 7 54 52o55i 63-19 999761 ■07 620790 63-26 479210 475414 6 55 524343 62-64 999757 •°7 524586 62-72 5 56 528102 62 -u 999753 •°7 528349 62-18 47i65i 4 -ll 53i828 61 -58 999748 •07 532o8o 6i-65 467920 3 535523 61 -06 999744 .07 535779 6i-i3 464221 2 5 9 539186 6o-55 999740 ■ 07 539447 60-62 46o553 1 6o 542819 60 -04 9997 35 Sine < .07 88° 543o84 60-12 456916 I | OOSJQO Cotang. D. Tang : 20 (2 DEGREES.) A TABLE OF LOGARITHMIC M. Sine D. Cosine ] D. Tang. D. Cotang. | o f i-5428i9 60-04 9-999735 -07 8- 543o84 60-12 11-4569161 60 453309! So 44973 2 1 58 446i83| Si 442664I 56 . i 546422 59.55 999731 .07 546691 59-62 2 3 549995 553 oiq 5g-o6 58-58 999726 999722 •07 •08 550268 553817 557336 59-14 58-66 4 557054 58-u 999717 .08 58- 19 57-73, 5 56o54o 5 7 -65 9997 1 3 .08 560828 439172, 55 43 5709 ' 54 6 563999 567431 57-19 999708 ■08 564291 \vv I 56-74 9997°4 999699 ■08 567727 56-82 432273 428863 Oi 670836 ■56-3o .08 5 7 1 1 3 7 56-38 52 9 574214 55.87 999694 999689 •08 574020 55- g5 420480 5i ID 577566 8-580892 55-44 .08 577877 8- 581208 55-52 422123 5o II 55-02 9-999685 .08 55-10 11-418792 4i5486 % 12 584193 54- 60 999680 •08 5845 U 54-68 i3 587469 54-19 999675 •08 587795 591031 54-27 4l22o5 47 - 14 59072 1 53-79 999670 .08 53-87 408949! 46 i5 593948 53- 3 9 999665 .08 5 9 4283 53-47 53- 08 . 4067 1 jl 45 16 597152 53-00 999660 ■08 597492 402508 44 \l 6oo33a 52-6i 999655 •08 600611 52-70 399323 43 603485 60662,) 52-23 ■ ggyuSo .08 6o383o 606978 52-32 396161 42 '9 5i-86 9996^5 -og 5i -g4 5i-58 5l-2I 3o3o22 41 2q 21 609734 8.612823 51-49 5l-I2 99g640| -og 9-999635 -og 610094 8-613189 389906 n-38681 1 40 22 6i58qi 618937 5o-7& 999629 •og 616262 5o-85 383738 23 5o-4i 999624 • 09 6i93i3 5o-5o 380687 17 H 621962 5o-o6 999619 .09 622343 5o-i5 377657 374648 36 25 624965 49-72 999614 -09 623352 49-81 35 26 627948 49-38 999608 -og 628340 49-47 49 -i3 371660 34 u 63ogii 49-04 48-71 48 -3g 99g6o3 ■ 09 63i3o8 368692 33 633854 - 99g5g7 -og 634256 48-80 365744 362816 32 29 636776 639680 9995g2 -og 637184 48-48 3i 3o 48-06 999586 -og 64ooo3 8 •642982 645853 48-16 359907 11-357018 3o 3i 8-642563 47-75 9-999581 •09 47-84 2I 32 645428 47-43 999 5 7 5 •09 47-53 354U7 33- 648274 47-U 999570 .09 648704 65i537 47-22 351296 27 34 65iio2 46-82 999564 .09 46-91 46-61 348463 26 35 65391 1 46-52 999558 • 10 654352 345648 25 36 n 656702 659475 662230 46-22 45-92 999553 999547 ■10 ■ 10 66714c 65g92i 46-3i 46-02 ,34285i 340072 24 23 45-63 99g54i • 10 662689 665433 45-73 3373 1 1 22 3 9 664968 45-35 ggg535 • 10 45-44 334567 21 40 667689 . 8-67o3o3 673080 45- 06 9gg52g ■ 10 668160 45-26 33i84o 20 41 44-79 9-999324 • 10 8-670870 44-88 n-32gi3o 326437 \l 42 44-5t 9gg5i8 • 10 673563 44-6i 43 676751 44-24 99g5i2 • 10 676239 44.34 323761 17 44 678405 681043 43-97 99g5o6 .-10 678qo< 44-17 321 100 16 45 43-70 99g5oo ■ 10 681644 43- 80 3 1 8456 i5 46 683665 43-44 999493 ■ 10 68417! 686784 43-54 3i5828 14 % 686272 43- 18 999487 • 10 43-28 3i32i6 i3 688863 42-92 99948i • 10 68g38i 43-o3 3 1 06 19 12 49 691438 42-67 999475 •IC 69196- 694321; 42-77 42-52 3o8o3- 11 5o 693998 8-696043 42-42 999469 9-99g46c ■15 305471 10 5i 42-17 ■II 8-697081 42-28 11-302910 3oo383 8 5s 699073 701589 41-92 41-68 999456 ■II 6gg6i- 42 -o3 53 99945o • II 702 13< 41-70 4i-55 297861 I 54 704090 41-44 ggg443 -II 70464c 1 ' 295354 55 706577 41-21 999437 -II 70714c 41-32 292860 5 56 709049 40-97 99943i •II 7096 1 1 4i- 08 290382 287917 4 u 711507 40-74 99942/ • 11 71208; 40-85 3 ' 7i3a52 716383 40-31 999418 • 11 71453/ 40-62' 285465 2 59 40-29 9994 1 1 • 11 71697; 7ig3gf 4o-4o 283028 1 60 718800 4o 06 999404 •II 40-17 28060/ Cosine D. Sine 87 1 *! Cotang. D. Tang. M. SINES AND TANGENTS (3 DEGREES.) 21 M. Sine D. Cosine D. Tang. D. Cotang. { o 8-718800 4o- 06 9-999404 -11 8-719396 4o 17 11-280604 60 , > 721204 39-84 999398 • 11 721806 ?9 9 5 278194' So ) 2 723595 39*62 . 999391 999384 ■11 724204 3g 74 275796 58 3 725972 728337 " 39-41 -11 726588 39 52 273412! 57. 4 3l-o? 999378 •11 728959 73i3i7 39 3o 271041I 56 5 73o688 999371 •11 39 09 268683! 55 6 733027 38-77 999364 • 12 733663 38 89 266337] 54 I 735354 38-57 999357 •12 735996 38 68 264004! 53 737667 38-36 999350 •12 738317 38 48 26l683 52 9 73.9969 38-i6 999343 •12 740626 38 27 259374 5i 234754 40 21 8-766675 35-88 9-999257 ■12 8-767417 769578 36 00 n-232583, 3o 23o422J 38 22 768828 35.70 999250 • i3 35 83 23 770970 35-53 999242 •i3 771727 35 65 2282731 37 24 773ioi . 35-35 999235 •i3 773866 35 48 226134 36 25 775223 35.i8 999227 •i3 775995 35 3i 224oo5 35 26 777333 35-oi 999220 ■i3 778114 35 14 221886 34 ■ 27 779434 34-84 999212 •i3 780222 34 V, 219778 33 28 78i524 34-67 999205 •i3 782320 34 2 1 7680 32 29 ~7836o5 34-5i 999197 999189 •i3 784408 34 64 215592 3i 3o 785675 34-3i -i3 786486 34 i 1 2i35i4 3o 3i 8-787736 34-i8 9-999181 ■i3 8-788554 34 3i 11-211446 29 32 » 34-02 999 '74 •i3 790613 34 i5 209387 207338 28 33 33-86 999166 ■i3 792662 33 8 27 34- 793859 33-70 999158 -i3 794701 33 205299 26 35 795881 33-54 999150 -i3 796731 33 68 203269 25 36 797894 33- 3 9 33-23 999142 ■i3 798752 800763 33 52 201248 24 12 799897 801892 999134 •i3 33 37 199237 23 33- 08 999126 • i3 802765 33 22 197235 22 3 9 803876 32-g3 9991 18 -i3 8o4758 33 °7 195242 21 40 8o5852 32-78 999110 ■i3 806742 32 9? 193258 20 41 8-807819 32-63' 9-999102 • i3 8-808717 32 t 11-191283 '9 42 809777 _32-49 999094 •14 8io683 32 1893171 18 187359 17 ' 43 811726 32-34 999086 •14 81 2641 32 48 44 8i366 7 32-IO 999077 ■14 814589 32 33 189411 16 ' 45 815599 32-65 999069 •14 816529 32 19 1 8347 1 15 ; 46 817522 3: -91 999061 •14 818461 32 OD 181539 14 ' % 819436 3r-77 999053 •14 820384 3i 9' 179616 i3 ; 821343 3i-63 999044 •14 82229S 3i B- 177702 12 49 823240 3i-49 31.35 999036 •14 824205 3i 175795 273897 11-172008 11 * 5.6 825i3o 999027 •14 826103 3i 5o 10 5i 8-827011 3l-22 9-999019 •14 8-827992 3i 36 I 52 828884 3i-o8 999010 •14 829874 3i 23 170126 53 830749 3o-g5 3o-82 999002 998993 •14 83i748 3i 10 168252 n 54 832607 •14 8336i3 3o 96 166387 6 55 834456 3o.6g 998984 •14 835471 3o 83 i645»o 5 56 836297 838i3o 3o-56 998976 •14 837321 3o 70 162679 4 % 3o-43 998967 • i5 839163 3o 57 160837 3 839956 3o-3o 998958 -i5 840998 3o 45 159002 2 ■ 59 841774 843585 30-17 998950 ■ i5 842825 3o 32 157175 1 60 3o-oo 998941 • i5 844644 30-19 155356 Cosine D Sine 36° Cotang. D. Tang. M. _ !2 (4 DEGREES .) A TABLE Or LOGARITHMIC M. Sine | D. | Cosine n. Tang. D. Cotang. | 3,843585 3o-o5 9-998941 •i5 8-844644 3o-i9 11 -155356 60 i 845387 29-92 998932 ■ i5 846455 3o-o7 153545 & l 847183 29-00 998923 ■i5 848260 29«o5 29-82 151740 3 848971 29-67 998914 •i5 830057 149943 148154 n 4 85o75i 29-55 998905 • i5 85i846 29-70 5 852525 29-43 998896 998887 • i5 853628 29-58 146372 55 6 854291 29-31 ■i5 855403 29-46 144597 54 I 856o49 29-19 998878 •i5 867171 858932 29-35 142829 141068 53 857801 29-07 998869 •i5 29-23 52 9 859546 28-96 28-84 998860 -i5 860686 29-11 i3g3i4 5i 10 861283 998801 •i5 862433 29-00 28-88 137567 5o II 8-863014 28-73 9-998841 • i5, 8-864173 11 -135827 % 12 864738 28-61 998832 ■i5, 865906 28-77 28-66 134094 i3 866455 28 -5o 998823 •16 86 7 632 132368 % 14 868i65 28 -3o 28-28 998813 .16 86 9 35i 23-54 130649 i5 869868 ' 998804 ■16 871064 28-43 128936 45 16 871565 28-17 28-06 998795 •16 872770 28-32 127230 44 \l ,873255 998785 ■16 874469 28-21 1 2553 1 43 874938 876616 27-95 998776 ■16 876162 28-11 123838 42 19 27-86 998766 ■16 877849 28.00- I22l5l 4i 2l< 878285 27-73 998757 ■16 879529 27.89 1 2047 1 40 21 8-879949 881607 27-63 9-998747 ■16 8-881202 27.79 II 1 1 8708 ll 22 27-52 998738 ■16 882869 27.68 i i 71J1 23 883258 27-42 998728 •16 88453o 27.58 1 1 5470 ll 24 834oo3 886542 27-3i 998718 ■16 886 1 85 27-47 u38i5 25 2.7-21 998708 ■16 887833 27-37 112167 35 26 888174 27-11 998699 ■16 889476 27-27. no524 34 U 889801 27-00 998689 •16 891112 27-17 108888 33 891421 26; 00 998679 •16 892742 27-07 107268 32 2 9 893o35 26-80 998669 •17 894366 -26-97 26-87 io5634 3i 3o 894643 26-70 998659 ■17 896984 8-897596 104016 3o 3i 8-896246 26-60 9-998649 ■17 26-77 11-102404 29 32 807842 26-5i 998639 •17 899203 26-67 100797 28 33 899432 26-41 998629 •17 900803 26-58 099197 27 34 901017 a6-3i 998619 •'7 902398 903987 906070 26-48 097602 26 35 902596 26-22 998609 •■7 26-38 096013 25 36 904169 26-12 998599 ■■" 26-29 094430 24 ll 905736 26 -o3 998589 •17 907147 908719 910285 26-20 092853 23 907297 908853 25-g3 998678 •17 26-10 091281 089715 0881 54 22 3 9 25-84 9 9 8568 ■n 26-01 21 4o 9 r 0404 25-76 998558 ■17 91 1846 25.92 25-83 20 41 8-911949 913488 25-66 9-998548 •17, 8-913401 11-086599 \i 42 25-56 998537 •'7 914951 25-74 085049 o835o5 43 915022 25-47 998527 •17 916495 918034 25-65 \l 44 9i^55o 25-38 998516 ■18 25-56 081966 45 918073 ' 25-29 998506 •18 919568 25-47 o8o432 i5 46 919091 25-20 998495 998485 •18 921096 25-38 078904 077381 14 8 921103 25-12 •18 922611; 25 -3o i3 922610 25-o3 99S474 ■18 924136 25-21 075864 12 49 9241 1 2 24-9* 998464 .18 926649 25-12 07435i 11 ■5o 925609 24-86 998453 •18 927166 25 -o3 072844 10 5i 8-927100 24-77 9 •99 8 442 ■18 8- 9 28658 24-95 24-86 11-071342 o 52 9 28587 93oofS 24-69 998431 ■18 93oi 55 069845 53 24- 60 998421 •18 93i64" 24-78 068353 I 54 93i 544 24-52 998410 •18 933 i3^ 24-70 066866 55 933oi5 24-43 998399 998388 -18 934616 24-61 065384 5 56 934481 24-35 •18 93609: 9 3 7 565 24-53 063907 4 .3 935o42 937398 938850 24.27 998377 .18 24-45 062435 3 24-19 998366 ■18 939032 24.37 060968 069606 068048 2 59 24-11 998355 ■18 940494 941962 24-3o 1 6o 940296 ?4>o3 998344 .18 24-21 " Cosine D. Sins 85 c Cotang. D. Tang. M. 8INES AND TANGENTS (5 DEGREES.) 2) TT-.I Sine J D. Cosine j D. Tang. E • 21 Cotang. | - o £.940296 24- o3 9.998344 ■ 19 8-941952 24 n-o58o48' 6a I 94H38 23o4 23 §7 99H333 • 19 943404 24 i3 056596! ~5o o55i48' 58 2 g43 i 74 998322 -19 944852 24 o5 3 944606 23-79 998311 • 19 946295 947734 23 97 003705 57 4 946034 23-71 23-63 998300 • 19 23 90 032266 56 5 947K6 998289 • 19 949168 - 13 82 o5o832 55 a> 948874 950287 951696 23-55 998277 ■ 19 950597 23 -A 049463 54 7 23-48 998266 • 19 952021 • 23 66 047979 53 8 23-4o 998255 ■ 19 953441 23 60 046559 52 9 953ioo 23-32 998243 ■ 19 9 54856 23 5i o45 1 44' 5 1 10 954499 23-20 998232 ■'9 956267 23 44 043733 5o ii 8-9558 9 4 957284 958670 23-17 9.998220 ■19 8-957674 23 37 11 -042326' 49 040925* 48 12 23- 10 998209 •19 909075 23 23 i3 23-02 998197 998186 ■ 19 960473 23 039D27. 47 U 960062 22-95 22-88 •19 961866 23 14 o3oi34' 46 i5 961429 998174 •'9 963255 23 °7 036745; 45 16 962801 22-8o 998163 .19 J364639 23 00 o3536i 44 \l 964170 22-73 99S 1 5 1 ■19 966019 22 t o33 9 8i 43 965534 22-66 998139 998128 -20 967394 968766 22 032606 42 >9 966893 22-59 -20 22 79 o3i234' 4i 20 968249 22-52 9981 16 •20 970133 22 7< 029867 40 2! 8-969600 22-44 9-998104 ■20 8-071496 972855 22 65 Ii-0285o4! 3a 027145. 38 22 970947 22-38 998092 ■ 998080 ■ 20 22 t 1 23 972289 22-3l • 20 974209 22 5i 020791 37 24 973623 22-24 998068 • 20 97556o 22 44 024440 36 25 974962 22-17 998056 •20 976906 22 37 023094 35 021702 34 26 976293 22-10 998044 •20 978248 22 3o 23 977619 978941 22 o3 998032 .20 97 9 586 98092 1 22 23 020414! 33 21-97 998020 •20 22 '7 0190791 32 2 9 980259 9 8i5 7 3 8-982883 21-90 998008 -20 982201 22 10 - 017749: 3i 01 6423 1 3o 3o 21-83 997996 • 20 • 983577 22 04 3i 21-77 9-997985 •20 8-984899 21 97 ii-ciSioii 20 oi3 7 83! 28 32 984189 21-70 997972 •20 986217 21 11 33 983491 986789 988083 21-63 997959 ■20 987532 988842 21, oi2468i 27 34 21-57 997947 • 20 21 78 oin58| 26 35 21-50 997935 ■21 990 ! 49 21 71 ooo85 I i 25 008549! 24 36 989374 21-44 997922 •21 99I45I 21 65 Si 990660 21-38 997910 -21 992750 2i 58 0072501 23 991943 2I-3l 997897 •21 994045 21 52 005955| 22 3 9 993222 21-25 997885 • 21 995337 21 46 oo4663i 21 4o 994497 8-995768 21-19 997872 • 21 ■996624 21 40 0033761 20 41 21-12 9-997860 •2! 8-997908 21 34 11-002092 19 000812! 10 42 997036 998299 2i-o6 997847 -21 999188 21 27 43 21-00 997835 •21 g. OO046O 21 21 30-999535' 17 44 999560 20-94 20- 87 997822 ■21 OOI738 - 21 i5 998262' 16 45 9.000816 ■997809 -21 003007 21 ol 996993; i5 46 002069 20-82 997797 997784 -21 004272 21 995728! 14 % oo33i8 20-76 •21 oo5534 1 20 9- 1 9944661 i3 004563 20--"> 997771 •21 006792 20 u 9932081 12 49 oo58o5 20-6/t 997758 •21 008047 009298 20 991953 11 56 007044 9-008278 20-58 997745 -21 20 80 990702 10 5i 20-52 9-997732 •21 9-010046 20 74 10-989454; 9 988210 8 52 009510 20-46 9977 '9 •21 011790 20 68 53 010737 20-40 997106 997693 997680 •21 oi3o3i 20 62 986969 7 54 011962' 20-34 ■22 014268 20 56 985732 6 55 oi3i82 20-20 20-23 •22 oi55o2 20 5i 984498 5 56 014400 997667 ■22 016732 20 45 983268 4 u oi56i3 20-17 997654 ■22 017950 019183 20 40 982041 3 016824 20-12 997641 ■22 20 33 980817 2 5 9 oi8o3i 20- 06 997628 ■22 ,020403 20 28 978380 6o 019235 20-00 997614! ■22 021620 - — : 20-23 1 L Cosine . d: Sine !84° Cotang. 1 D. 22 24 (6 DEGREES.) A TABLE OV LOGARITHMIC M. I Sine D. 1 Cosine D. Tang. D. Cotang. 0-978380 977166 60 'q-oiq'235 20-00 9-997614 ■22 9-021620 20-23 i 020435 i 9 -o5 19-89 997601 ■22 022834 20-17 2 02l632 997388 •22 024044 20-11 975956 3 022825 19-84 997574 •22 02D25l 20- 06 974749 973545 tl 4 024016 19-78 997561 -22 026455 20-00 56 55 5 025203 19-73 997547 ■22 027655 028852 I9-95 972345 6 i 026386 19-67 997534 •23 \ 9 ai 971148 54* 2 027567 028744 19-62. 997520 •23 o3o<>46 969954 53 19-57 997507 ■23 o3 1 237 19.79 968163 5a 9 029918 19-5i 997493 997480 •23 032425 19-74 967575 5i 10 031089 19-47 •23 033609 19-69 96639 1 5o II 9-o32257 19-41 9-997466 •23 9- o3479 1 035909, 19.64 10-965209 3 12 o3342i i 9 -36 997452 •23 19-58 96403 1 i3 034582 19-30 997439 ■23 037144 i 9 -53 962856 %'. 14 035741 036896 19-25 997425 •23 q383i6 19-48 961684 i5 19-20 99741 1 •23 039485 19-43 9605 1 5 -45 16 o38o48 I9-I5 997383 •23 o4o65i ig-38 969349 958187 44 11 039197 19-10 •23 04i8i3 19-33 43 18 64o342 ig-o5 18-99 997369 997355 •23 042973 19-28 957027 42 '9 041485 •23 o44i3o 19-23 955870 4i 20 042625 18-94 18-89 997341 •23 045284 19-18 954716 40 21 9*043762 044895 9.997327 •24 9-046434 19-13 10*953566 31 22 18-84 9973 1 3 •24 047582 048727 049869 o5ioo8 19-08 952418 23 046026 18.79 18-75 697299 .24 19 -o3 18-98 961273 95oi3i 37 24 047i54 048279 997285 • 24 36 35 25 18-70 997271 •24 18-93 18-89 948992 947856 26' 049400 18-65 997257 •24 032144 34 11 o5o5ig o5i635 18-60 997242 ■24 053277 18-84 946723 33 18-55 997228 ■24 054407 18.79. 945693 32 29 052749 o^385o 9-054966 18 -5o 997214 ■24 055535 18-74 944465 3i 3o 18-45 99T99 9.997185 •24 o56659 18-70 943341 3o 3i 18-41 ■24 9-057781 058900 i8-65 10-942219 3 32 056671 18-36 997170 997166 • 24 18-69 18.55 941 100 33 057172 058271 i8-3i •24 060016 939984 938870 2 I 34* 18*27 997 141 •24 061 i3o i8-5i 26 35 059367 18-22 997 I2 7 •24 062240 ' 18-46 937760 25 36 060460 18-17 997112 ■24 063348 18-42 936652 3 n - 06,1 55 1 i8-i3 997008 99708J •24 064453 18-37 935547 062639 18-08 ■25 065556 i8-33 934444 22 39 063724 064806 18-04 997066 •25 066655 18-28 933345 21 40 17-99 997052 -25 067752 9- 068846 18-24 932248 20 41 9-o65885 17-94 9.997039 ■25 18-19 10.931154 w 42- 066962 ' n-jo 17-86 997024 •25 069938 i8-i5 930062 43 o68o36 997009 ■25 071027 072113 iS-IO 928973 927887 17 Ai 069107 17-8, 996994 ■25 18-06 16 45 070176 17-77 996979 ■25 073197 074278 18-02 92680.: i5 46 071242 17-72 996964 •25 '7-97 925722 14 % 072306 17-68 996949 •25 075356 17-93 17. §9 924644 i3 073366 17-63 996934 •25 076432 923568 12 49 074424 17.59 996919 •25 07t5o£ 078576 17-84 922495 I] 5o 075480 i7-5o 996904 9.996889 •25 17-80 921424 10 5i 9-076533 i7-5o ■25 9-079644 17-76 10.920356 \ 52 077583 078631 17.46 99687; 996868 •25 080710 17.72 919290 918227 53 17-42 ■25 of-:833 17-67 I 54 079676 080719 17-38 996843 ■25 17-63 9JJ167 ' 55 17-33 996826 ■25 o838gi I^ 91610c 9i5o53 5 56 081759 17-29 17-25 996812 • 26 084947 4 57 082797 o8383a 9967971 .26| 086000 17 -5i 914000 3 58 17-21' 996782! -26! 087050 17-47 912950 2 5 9 084864 17-17 i 7 -ii 996766 -26 088098 17-43 911- J2 I [ 66 085894 996751] -26! 089144 17-38 oio856| 1_ Conine D. Sine l83°i Cotang. 1 D. Tang. |m. 8INM8 AND TANGENTS. (7 DEGREES.) 2fi Jt. o Sine D. Cosine D. Tang. D. Co tang. 1 9-085894 17- 13 9-996751 ■ 26 9-089144 17-38 10-910856 60 I 086922 17-09 996735 ■26 09018- • 7-34 9008 iC 5 9 2 ' 087947 088970 17-04 996720 •26 1 09122s i7-3o 908775 58 3 17-00 996704 •26 092266 17.27 907734 57 4 089990 16-96 996688 •26 09330s 17-22 90669s 5b 5 091008 16-92 996673 •26 094336 17-19 17-13 oo566/ 55 6 092024 16-88 996607 ■26 09536- 90463; 54 2 093037 16-84 996641 •26 09639! 17- ii 90360! 53 094047 16-80 996625 ■26 097422 17-07 90257! 52 9 095o56 16-76 996610 ■26 098446 I7*o3 901554 5i 10 096062 16.73 996694 ■26 099468 16-99 900S3; 5o II 9- 097065 09,8066 16.68 9*996578 •27 9.100487 16-95 10-89951; t 12 16-65 996562 •27 I0l5o! 16-91 16-87 898496 897481 i3 099065 16-61 996546 •27 I025lC 47 '.4 100062 16-67 996530 ■27 io3532 16-84 896468 46 i5 ioio56 i6-53 996514 •27 104542 16-80 8 9 5458 45 16 102048 16-49 .996498 ■27 io555o 16-76 894450 44 \\l io3o37 i6-45 996482 ■27 Io6556 16-72 893444 43 104025" 16-41 996465 •27 107559 16-69 16-65 892441 42 J '9 ioSoio 16-38 996449 996433 ■27 io856o 891440 41 20 106992 16-34 ■27 109559 16-61 800441 40 21 9' 106973 i6-3o 9-996417 •27 9-iio556 16-58 io- 889444 888449 3 9 22 107951 16-27 996400 ■27 1 1 1 55i i6-54 38 23 108927 16-23 996384 •27 1 12543 16 -5o 887467 37 24 1 0990 1 16-19 996368 ■27 1 13533 16-46 - 886467 36 25 1 10873 16-16 996351 •27 1 1452 1 16-43 885479! 35 8844931 34, 26 1 1 1842 16-12 996335 • 27 n55o7 i6-3 9 3 I 1 2809 16-08 996318 :ll 116491 16-36 883509! 33 1 13774 i6-o5 996302 1 17472 1 18452 16-32 88252o| 32 39 1U737 1 1 56n8 16-01 996285 • 28 16-29 16-25 88i548i, 3i 3o i5-97 996269 • 28 ■ 1 1 94^9 880671 1 3o 3i 9-116656 15-94 9.996252 .28 9 • 1 20404 16-22 10-879596! 29 8786231 28 32 117613 - i5-9o 996235 • 28 121377 16-18 33 1 18567 i5-o 7 996219 ■ 28 122348 i6-i5 877652! 27" 34 119519 15-83 996202 -28 I233I7 16-n 876683; 26 35 120469' i5-8b 99&I85 ■ 28 124284 16-07 875716, 25 36 121417 i5- 7 6 J996168 •28 125249 i6'-o4 874751 1 24 u 122362 i5- 7 3 996151 • 28 12620 16-01 873789' 23 872828, 22 i233o6 15-69 996134 • 28 ' 127172 I28i3o 1-5-97 3 9 124248 15-66 9961 17 •28 15-94 87 1 870 21 40 125187 15-62 996100 ■28 1 29087 i5-gi 870913 20 4i 9-126125 i5-59 9.996083 • 29 9-i3oo4i i5-»7 10-869959 1 869006 IB 868o56' 17 867107 16 . 42 127060 15-56 996066 ■ 2 9 j 3,0994 15-84 43 . 127993 I23q25 15-52 996049 •29 131944 . i328 9 3 i3383 9 i5-8i i 44 i5-49 i5-45 996032 ' •29 15.77 45 1 29854 996016 ■ 29 15-74 866161 i5 46 130781 15-42 99599S •29 134784 I5-7I i5-6 7 8652i6 14 48 131706 i5-3 9 15-35 995980 •29 535726 864274 i3 I32WO 995963 •29 136667 15-64 863333 12 49 l3355i 15-32 995946 •29 137605 138542 i5-6i 8623951 11 86U58 10 56 134470 ■ 5-29 991928 • 2 9 15-58 5i 9-I35337 15-25 9-995911 995894 ■29 9-139476 15-55 io-86o524 8 52 i363o3 15-22 ■29 140409 i5-5i 8595gi 85866o 53 i3t2i6 i5- 19 995876 •29 1 41 34o i5-48 7 54 i33i2'-i i5-i6 995859 ■ 2 9i 142269 i5-45 857731 856804 6 55 139037 1 5- 1 2 996841 •29! 143196 i5-42 5 56 139944 i5-09 995823 •29 I44I2I 15-39 855879 4 11 140850 i5-ob 995806 •29 I45o44; 15-35 854966; 3 141754 i5.o3 995-788 • 29 I45g66 15-32 854o34 ■ 2 5 9 142655 15-00 996771 ■29 146885 I5.20 853u5 I ;.™_ 143555 14-96 995753I •2 9 | l47So3| 15-26 862197 |, Cosine J D. Sine i82°l Cotang. 1 x>. Tang. M. | 26 TIT (8 DEGREES.) A TABLE OF LOGARITHMIC "Sine o !y D. 20 21 22 23 21 25 26 11 3 9 o 3i 32 33 31 35 36 ll 39 4o H it a 44 45 46 % i 9 5o 5i 52 53 54 55 56 ll I 43555 144453 145349 146213 147'36 148026 1 48915 149802 1 5o686 i5i 369 1 5245 1 l5333o 1 54208 i55o83 155957 1 5683o 157700 i5856o 159435 i6o3oi 161164 9-162025 162885 163.713 164600 i65l54 166307 167159 168008 168856 169702 170047 171389 172230 173070 173908 171714 175578 176411 177242 178072 •178900 179726 i8o55i i8[37l 182196 i83oi6 183831 1 8465 1 185466 186280 • 187092 187903 188712 189519 190325 191 i3o 191933 192734 193534 19433a Cosine D. I Tang. Oos'me 14-9° 14-93 14-90 14-87 U-84 14-81 14-78 14-75 U-72 14-69 U-66 U-63 14-60 U-57 14-54 i4-5i 14-48 14-45 14-42 14-39 U-36 14-33 i4-3o 14-27 1 1-24 U-22 14-19 14-16 U-i3 14- 10 14-07 l4-o5 14-02 13-99 13-96 i3-9l i3-gi 13-88 13-86 13-83 i3-8o i3-77 i3-7l 13-12 i3-6g i3-66 13-61 i3-6i i3-59 13-56 13-53 l3-5i 13-48 13-46 13-43 13-41 13-38 13-36 13-33 i3-3o i3-28, D. , Coteng. 9.9,5753 995735 995717 $& 995664 oo5646 995628 - 9956 1 995591 995573 9-995555 995537 995519 99 55oi 995482 995464 995446 995427 995409 905390 9-995372 995300 995331 9953i6 995297 995278 995260 9952I1 995222 995203 9.995184 995165 995146 99 5i27 995108 995089 995070 995001 095o32 99^013 9.99I993 994974 99 1 9 5d 994935 99 19 l6 994896 991877 99 l857 991838 99IS18 9-991798 994779 9947 5 9 99 n3 9 991719 991700 991680 994660 99 l6lo 99I620 3o ■3o •3o ■3o -3o -3o ■3o •3o ■3o •3o •3o ■ 3o -3o -3o ■3i -3i •3i •3i •3i -3i ■ 3i • 3i ■ 3i ■ 3i •3i -3i -3i -3i *-32 -32 •32 •32 •32 •32 • 32 ■ 32 ■32 •32 ■32 •32 • 32 -32 .32! ■32 •32 • 33 • 33 ■ 33 • 33 •33 ■ 33 .33 • 33 • 33 ■33 • 33 .33 .33 • 33 • 33 • 33 ■1 I7803 148718 149632 i5o544 i5i454 1 52363 153269 i5li74 155077 155978 156877 •157775 1 586 7 i5 9 565 160457 161 347 162236 i63i23 163774 •166654 167532 168409 169 170157 171029 171899 172767 173634 174499 .175362 176224 177084 177942 178799 179655 180308 i8i36o 1 822 1 1 i83o59 (■183907 184752 185597] 186439 1 187280 18979! 190629 191462 •19229I 193121 I 9 3 9 '53 101780 195606 196430 197253 198074 198894 I997'3j i5-26 15-23 15-20 15.17 i5-i4 i5-ii i5-o8 i5-o5 I5'02 14-99 14-96 14-93 14-90 14-87 U-81 U-8i i4-7 9 14-76 U-73 14-70 14-67 14-64 il-6i U-58 U-55 14-53 i4-5o 14-47 U-44 14-42 14-39 14-36 14-33 i4-3i 14-28 14-25 14-23 14-20 14-17 14- 15 U-I2 14.09 11-07 14-04 1402 13-99 i3-g6 i3-g3 i3-oi i3-8g 13-86 13-84 i3-8i 13-79 13-76 i3-74 i3- 7 i i3-6g 13-66 13-64 i3-bi 10-8521Q7 851282 85o368 849456 848546 847637 846731 845826 844923 844022 843i23 I0'842225 841329 840433 83 9 543 838653 837764 836877 835992 835io8 834226 10-833346 832468 83 1 59 1 830716 829843 82897 828101 827233 826366 8255oi 10-824638 823776 822916 822058 821201 820345 819492 818640 817789 8169I1 10-816093 8i52l8 8i44o3 8i356i 812720 81 1880 811042 810206 809.37 8o8538 0-807706 806876 806047 8o5220 804394 803570 802747 801926 801 106 800287 6c ir oo 55 54 53 52 5i 5o % 47 46 45 44 43 42 41 4o 3 9 38 37 36 35 34 33 32 3i 3o \% 27 26 25 2-1 23 22 21 20 D. S ,ii e I HI ! Cotang- Tang. I K. SINKS AND TANGENTS. (9 DEGREES.) 27 M. Sine D. Cosine D.| Tang. | D. | Cotang. 60 9-I94332 13-28 9.994620 • 33 9-199713, i3-6i' 10-800287 i 196129 195925 13-26 994600 • 33 200520 20i345| i3-5o 799471 3 3 i3-23 994580 • 33 i3-56 798655 3 196719 13-21 994560 • 34 202159: 13-54 797841 57 4 19J5h 198302 i3-i8 994540 ■34 20297 1 1 i3-52 797020 796218 56 I 5 13-16 994519 •34 203782I i3-49 55 6 199091 13-13 , • 994499 • 34 204692 13-47 795408 54 I 199879 i3-ii 994479 • 34 2o54oo i3-45 794600 53 200666 i3-o8 994456 994438 • 34 v ' 206207 20701J 13-42 793793 52 9 201431 i3-o6 •34 i3-4o 792987 5i 10 202234 i3-o4 994418 • 34 207817 9.208619 13-38 792183 5o n 9-203017 i3-oi 9.994397 ■34 13-35 io-79i38i % 12 203797 " 12-99 994377 • 34 209420 13-33 790580 789780 788982 13 204577 12-96 994357 •34 210220 i3-3i 47 14 2o5354 12-94, 994336 •34 211018 i3-28 46 15 2o6i3i 12-92 12-89 9943i6 • 34 2ii8i5 i3-26 788 1 85 45 16 206906 994295 •34 212611 13-24 787389 7865,5 44 \l 207679 208452 12-87 994274 • 35 •• 2i34o5 13-21 43 12-85 994254 •35 214198 214909 i3- ig 785802 42 "9 209222 J2-82 994233 ■35 '?"Z ■78501 1 41 20 209992 I2-8o 9942 1 2 • 35 216780 i3-i5 784220 40 21 9-210760' 12-78 9-994191 •35 9-216568 13-12 10.78343,2 39 22* 211626 12-75 994171 •35 217356 218142 i3-io 782644 38 23 2 1 220I 2i3o55 12-73 ' 994160 ■35 ]3-o8 781858 37 U 12-71 994129 994108 •35 218926 i3-o5 781074 36 25 2i38i8 12-68 • 35 219710 13-03 780290 35 26 214579 215338 12-66 994087 •35 220492 i3-oi 779508 778728 34 2 12-64 994066 •35 221272 12-99 33 216097 216854 I2-6I 994045 ■35 222002 12-97 777948 32 2 9 12-59 994024 ■35 222830 12-94 777179 3< 36 217609 9-218363 12-57 994003 •35 2236o6 12-92 776394 3o 3i 12-55 9-993981 ■35 9-224382 12-90 10-775618 3 32 219116 12-53 993960 •35 225i56 12-88 774844 33 219868 1:2 -50 99 3 9 3 9 993918 •35 225929 12-86 774071 27 34 220618 12-48 •35 226700 12-84 7733oo 26 35 22l367 222115 12-46 993896 ■36 227471 228239 12-8l 772529 25 36 12-44 993875 ■ 36 12-79 771761 24 ll 222861 12-42 993854 ■ 36 229007 12-77 770993 23 2236o6 12-39 993832 •36 229773 12-75 770227 22 3 9 224349 12-37 99381 1 • 36 23oo39 12-73 769461 768698 10-767935 21 4o 225092 9-225833 12-35 993789 • 36 23i3o2 12-71 20 41 12-33 9-993768 •36 9-232065 12-69 \l 42 226573 I2-3I 993746 ■36 232826 12-67 12-65 767174 43 22?3i 1 12-28 993725 ■36 233586 766414 \l 44 228048 12-26 993703 ■ 36 234345 12-62 7 65655 45 228784 12-24 993681 ■ 36 235io3 I2-6o 764897 i5 46 229518 12-22 993660 •36 235859 12-58 764141 14 % 230252 12-20 993638 ^36 -2366i4 12-56 763386 i3 230984 12-18 993616 • 36 237368 238120 12-54 762632 12 49 23l7l4 I2-l6 993594 •37 12-52 761880 11 5o 232444 12-14 993572 ■3 7 238872 12 -5o 761 12S 10 5 t 9-233172 12-12 9-99355o •37 9.239622 12-48 10-760376 I 52 233899 234625 12-09 993528 'V 240371 12-46 759629 758882 53 12-07 9935o6 ■37 241118 12-44- I 54 235349 23607J 12-05 993484 •37 241865 12-42 758i35 55 I2o3 993462 •37 242610 12-40 757390 5 56 ' 236795 12-01 993440 •?7 243354 12-38 756646 4 u 2375i5 11-99 993418 •37 244097 244839 12-36 75590; 3 238235 n-97 993396 • 3 7 12-34 755i6i 2 5o 238o53 239670 1195 993374 •3 7 245579 12-32 '754421 1 66 11-93 99335i •37 246319 12-30 . 75368i b Cosine D. Sine 80° Co tans- D. Tang. il-J r— 22 * 28 (10 DEGREES.) A TABLE OF LOGARITHMIC M. Bine D. Cosine D. Tang. D. Cotang. 10-753687 «l 9-239670 240386 I.. 9 3 9-99335i •*l 9-246319 12 -3o i \\Z 993329 -3 7 247057 12-28 752943 n 2 241 101 993307 ■? 7 247794 12-26 752206 3 241814 II.87 993285 •37 24853o 12-24 751470 750736 57 4 242526 11 -85 993262 •37 249264 12-22 56 5 243237 H-83 993240 :ll 24999 s 25o-j3o 12-20 750002 55 6 243947 11. 81 993217 I2-I8 749270 54 I 244.656 H-79 993195 • 38 25i46i 12-17 748539, 53 245363 W.]l 993172 ■ 38 252191 I2-l5 747809 5a 9 246069 24677^5 993149 ■38 252920 I2-I3 747080 5i 10 n-73 993127 • 38 253648 12-11 746352 5o ii q- 247478 248181 11-71 9-993104 •38 9-254374 12 09 10-745626 49 12 11-69 993081 •38 255ioo 12-07 744900' 48 -i3 248883 11-67 993059 ■38 255824 12 o5 744176 743453 47 14 249583 u-65 993o36 •38 256547 1203 46 o 2502L2 n-63 9930 1 3 •38 257269 12-01 742731 45 16 250980 n-6i 992990 ■38 257990 258710 12-00 742010 44 17 251677 , 2J237J n-5g 992967 •38 II.98 7412901 43 i3 n-58 992044 •38 259429 II.96 740571 42 '9 253067 u-56 992921 • 38 260146 n-94 739854 41 20 253761 n-54 992898 ■ 38 26o863 11-92 739i3 7 40 21 9-254453 n-52 9-992875 •38 9-261578 11 -90 10-738422 39 22 255i44 11 5o 9928D2 •38 262292 11-89 737708 38 23 255S34 n-48 992829 • 3g 263oo5 11.87 736995 ll 24 256523 n-46 992806 •39 263717 264428 n-85 736283 23 257211 n-44 9927S3 -3 9 n-83 735572 35 26 257898 258583 11-42 992759 -3 9 2 65i38 11-81 734862 34 11 U-4I 992736 -3 9 265847 Il:?8 734153 33 25 9 268 ii-3 9 992713 -3 9 266555 733445 32 ? 25 99 5i 1. -3 7 992690 •39 267261 n.76 732739 732033 3i 3o 26o633 n-35 992666 •3g 267967 9-268671 n-74 3o 3i 9-261314 n-33 0-99^043 -3 9 11-72 io-73i32o 730623 3 32 261994 u-3i 992619 -3 9 269375 11-70 33 262673 263351 n-3o 992596 ■39 270077 11-69 729923 27 34 11-28 992572 •39 270779 11.67. II-OJ 7202_2l| 26 728321! 25 35 264027 26470J 11-26 992549 •39 271479 36 11-24 992320 •39 272178 n-64 727822! 24 ll 265377 11-22 9925oI -3g 272876 11-62 727124 23 266o5 1 11-20 992478 •40 273573 11 -6o 726427 22 3 9 266723 11-19 992454 ■40 274269 n-58 72573l 21 4o 267395 9.268065 WM 992430 •40 274964 n-5 7 725o36 20 41 9-992406 •40 9-275658 11-55 10-724342 IS 42 268734 11 - 13 9923S2 •40 27635i n-53 723649 43 269402 1 1 - 1 1 992359 •40 2-7043 n-5i 722957 17 4> 270069 270735 11-10 992333 •40 277734 278424 n-5o 722266 16 45 11-08 9923l 1 • 40 11,48 721576 720887 i5 46 27:400 nc6 992287 992263 • 4o 279113 n-47 14 % 272064 n-o5 • 40 279801 280488 u-45 720199 i3 272726 11 -o3 992239 •40 n-43 719612 12 i 9 273388 11-01 992214 •40 281174 1 1 -4i 718826 11 5o 274049 9 274708 275367 10.99 10-98 992190 •40 28i858 ii-4o 718142 10" 5i 9-992166 ■40 9-282542 n-38 10 717458 I 5: 10-96 992142 ■40 283225 n-36 716775 53 276024 •10-94 992117 •41 283907 184588 1 1 -35 716093 7 54 276681 10-92 992093 •41 n-33 715412 6 55 277337 IO-QI 992069 •41 285268 ii-3i 714732 5 56 277991 278644 IO-8 9 992044 •41 385947 286624 n-3o 7i4o53 4 5 7 IO-87 992020 ■41 11-28 713376 3 5B 279297 279948 280599 CoBJr.s 10-86 99I996 ■41 287301 II-26 7 1 2693 3 !5 1084 991971 ■41 287977 11-23 7 1 202 j 1 60 10-82 991947 Siiio ■41 793 388652 Cotimg." n-23 7II348 a Tnug. ». 8IKES AND TANGENTS (11 DEGUEES. ) ■'M. Sine D. 1 Cosine | D. 1 Tang. D. Cotang. 9 ■ 280599 10-82 9-991917 -4i 9-288652 11-23 10-711348 I 281248 10-81 991922 ■41 289326 11-22 710674 2 3 281897 10-79 991897 ■41 289999 11-20 710001 282544 10.77 991873 -4i 290671 11-18 709329 4 5 6 283190 283836 10-76 991S48I -4i 291342 11-17 708658 10-74 991823I -4i 2920K ii-i5 707987 284480 10-72 991799 -4i 292682 11-14 707318 I 285i24 10-71 991774] -42 293350 II -12 7o665o 285766 10-69 991749 -42 29 10 1 7 II-II 705983 7o53 16 9 286408 10-67 991724, -42 29 ',684 11-09 10 287048 10-66 991699 ■42 29534c 9-29601^ 11-07 704651 ii 9-287687 10-64 9-99167! ■42 11 -06 10-703987 703323 12 288326 10-63 991649 ■42 296677 u-o4 i3 288964 10-61 991624 •42 297339 n-o3 702661 14 * 289600 io-5n 991599 •42 291001 11-01 701999 i5 16 2Q0236 io-58 991674 •42 2g%62 I 1 -00 701338 .290870 io-56 991549 •42 299322 10-98 700678 \l 291504 10-54 991524 ■42 299980 10-96 700020 292137 292768 10-53 99149? ■42 - 3oo638 io-t;5 699362 ig IO-?I 991473 ■42 3oi2o5 301901 10-93 698705 20 293399 I0-5o 991448 ■42 10-92 698049 :o -697393 696739 21 9-294029 294658 10-48 9-991422 ■42 9-302607 16-90 22 10-46 991397 ■42 3o326i 10-89 23i 295286 / io-45 991372 ■43 " 3o3ni4 jo- 87 696086 24 295qi3 296039 10-43 991346 ■43 3o4»7 3o52i8 10-86 695433 25 10-42 991321 ■43 10-84 694782 26 297164 10-40 991295 •43 3o586 9 10-83 694i3r 11 297788 10-39 991270 ■43 3o65iq io-8i 6 9 348i 298412 10-37 991244 ■43 307168 10-80 692832 I 9 299034 10-36 991218 ■43 3078 1 5 3o8463 10-78 692185 3o 3i 299655 10-34 991 193 ■4? 10-77 691537 9-300276 10-32 9-991167 ■43 9-309109 10-75 10-690891 32 300895 io-3i 991 141 ■43 309754 10-74 600246 ' 33 3oi5i4 I0-2O 991 1 i5 ■43 3 1 0398 10-73 689602 34 302132 10-28 991090 •43 3uo42 10-71 688958 6883 i5 35 302748 10-26 991064 •43 3n685 10-70 36 3o3364 10-25 99io38 •43 3i2327 10.68 687673 12 - 3o3o79 10-23 991012 • 43 312967 10-67 687033 ■304093 10-22 990986 •43 3i36o8 10-65 6863 9 2 3 9 3o5207 10-20 990960 ■43 • 3 14247 10-64 685 7 53 40 3o58i9 10-19 990934 ■44 3 14885 16-62 685u5 ' 41 9"3o643o 10-17 9 • 990908 •44 9-3i5523 10-61 10-684477 42 307041 10-10 990882 ■44 3i6i5q 316795 3 17430 Io-6o 683841 43 307650 308259 10-14 99oS55 •44 10-58 683205 44 io-i3 990829 990803 •44 10-57 682570 45 308867 IO-II •44 318064 10-55 681936 46 309474 3 1 0080 10-10 990777 •44 318697 10-54 68i3o3 2 10-08 990750 •44 319329 io-53 680671 3 io685 10-07 990724 ■44 319061 320092 io-5i 68oo3o 679408 678778 i 9 311289 3 1 1893 io-o5 990697 •44 io-5o 5o 10-04 99067 1 •44 321222 10-48 5i 9-3 12495 10 -o3 9-990644 ■44 9-32i85i 10-47 10-678149 52 313097 313698 10-01 990618 •44 322479 10-45 677521 53 10-00 990591 ■44 323 106 10-44 676894 54 314297 1 9-98 990565 -44 990538 .44 99o5ii| -45 323733 10-43 676267 55 314897 9'97 324358 io-4i 675642 56 31549D 9-96 32jqS3 10-40 675017 57 316092 9-94 990485! -45 3256o-7 10-39 674393 673769 58 316689 9-93 990458] -45 32623! io-37 5 9 317284 991 99043 1 : -45 3268^3 10-36 673147 60 317879 9-90 990404 -45 327475 io-35 672525 Cosine D. Sine 78° Cotang. L>. Tang. 29 1 60 5o Mr. ' 30 (12 DEGREES.) A TABLE OF LOGARITHMIC M. i Sine D. Cosine .| D. 1 Tung-. D. Cotang . 1 9-317879 3i8473 9.90 9-88 9-990404 -45 9-32747 i 10-35 10672526 60 i 990378 1 -45 32S095 io-33 671906! 5o 671285 58 2 319066 9-87 99035 -45 32871 ) 10-32 3 3 19638 9:86 990324 -45 329334 io-3o 670666 57 4 320249 9.84 990207 -4! 32995. 33o5tc 10-20 67004- 56 5 320840 9-83 99027c -4; 10 28 66943c 66881 3 55 6 32i43o 9-82 99024; •4! 3311ft- ios6 54 I 322019 9-80 99021' •4' 33i8oC 10-25 66819- 66 7 58s 53 322607 9-79 99018? •4c 33241? 10-24 52 1 9 323ro4 9-77 990161 ■45 333o3^ 10-23 666967 666354 5i 1 10 323780 9-76 990 1 3^ •45 33364C 10-21 So • ii 9-324366 9.75 9-99010- ■46 9-334255 10-20 10-665741 % 12 32495o 9- 7 3 990079 •46 334871 lo- 19 665 12c i3 325034 9-72 990652 •46 335482 10-17 6645i( s 14 3261 17 9-70 • 990025 989997 ■46 33609c 10- 16 66390- 663 298 662689 i3 326700 5.69 ■46 336702 1 • 1 5 45 16 327281 9. 6ft 989970 ■46 3373 1 1 io-i3 44 \l 327862 9-66 989942 •46 337919 338527 10-12 662081 43 328442 9-65 989915 •46 10-11 66i473 4» >9 32902! 9.64 989887 ■46 33gi33 10-10 660867 41 20 329599 9-62 989860 ■46 339735 10-08 660261 40 21 9-330176 9-61 9-989832 •46 9-34o344 10-07 10-659656 18 :2 33oi53 o- 60 989804 •46 340948 io-o6 65oo52 23 33i3:o 33190J 9-58 989777 ■46 341552 10-04 658448 37- 2i 9 -5 7 989749 ■47 342155 io-o3 657845 36 ' 2J 332478 9-56 989721 •47 342757 343358 10-02 657243 35 . 26 333o5i 9-54 989693 '•47 10-00 656642 34 3 333624 9-53 989665 ■47 343o58 344558 9'99 656o42 33 334195 9-52 989637 ■47 9-98 655442 32 ?9 334766 9-5o 989609 •47 345i57 9-97 654843 3i 3o 33533j 9-335906 9.49 989582 ■47 345 7 55 •9-96 654245 3o 3i 9.48 9-989553 ■47 9-346353 994 10-653647 29 32 336475 9.46 989525 •47 346949 347545 9-93 653o5i .28 33 337043 9-45 989497 •47 9-92 652455 27 34 33i6io 9-44 989469 •47 348141 9-91 65 1 859 65i265 26 35. 338176 9-43 989441 •47 348735 9-90 25 36 338742 9-41 9 8 9 4i3 ■47 349J29 9-88 660671 24 u 339306 9-4o 9 8 9 384 ■47 349922 9- §7 9-86 ■ 660078 23 339871 9-3g 9 8 g 356 •47 35o5i4 649486 648894 22 3 9 340434 9-37 989328 •47 35no6 9-85 21 40 340996 9 -34i 558 9-36 989300 •47 35i6o7 9-83 6483o3 20 41 9-35 9-989271 •47 9-352287 352876 9-82 10-647713 !o 42 342119 9-34 989243 •47 9-81 647124 43 342679 9-32 989214 •47 353465 9-80 646535 \l 44 3432J9 9-3i 989186 •47 354033 9-79 645947 645360 45 343797 344355 9-3o 989157 989128 •47 354640 9'77 ■i5 46 9-29 •48 355227 9-76 644773 14 2 344912 9-27 989100 •48 3558i3 9-75 644187 i3 345469 9-26 989071 •48 3563o8 356982 357566 9-74 643602 12 £> 346024 9-25 989042 •48 9-73 643oi8 11 5o 346579 9-24 989014 9-988985 •48 9-71 642434 10 5i j-347134 9 22 -48 9-358i49 9-70 io-64i85i ? 52 347687 348240 9.. 21 9 88 9 56 ■48 35873i o-6o 641269 53 9-20 988927 988898 •48 35931 3 9.6ft 640687 7 54 348792 9-19 ■48 35 9 8g3 9-67 640107 5 55 349343 9.17 9.16 988869 •48 360474 o-66 639526 638947 638368 5 56 349893 988840 •48 36io53 9-65 i n 350443 9- 15 98881 1 •49 36i632 9-63 3 350092 35 1 540 9-14 988782 ■49 362210 9-62 637790 1 5 9 9- 13 988753 ■49 362787 9.61 637213 1 6o 352088 9-n 988724! •49' 363364 9.60 . 636636 Coaini: | T>. Sine J JO Coianp;. ! D. Tang. I M. SIXES AND TANGENTS (13 DEGREES ) 3} I'm. Sine r>. Cosine D. T49 Tang. D. Cotang. ■ 9-352o88 9-n 9-988724 9-363364 -9.60 I0-63663C 60 I 352635 9-10 988695 • 49 36394a 36451 5 9- 5a 9-58 636o6c 5 9 2 353i8i 9.09 988666 .49 635485 58 3 .353726 9-08 9 88636 ■49 365ooa 9.57 634910 634336 57 4 354271 9-07 988607 •49 365664 9-55 56 ..5 354*i5 9-o5 9 885 7 8 •49 366237 9-54 633763 55 6 355358 9-04 988548 •49 3668io 9-53 633190 54 I 355901 9-o3 988519 ■49 367382 9-52 632618 53 356443 9-02 988489 .49 36 79 53 9-5i 63204" 52 9 356984 O-OI 988460 •49 368024 9-5o 631476 5i 10 35732: 8-99 988430 •49 369094 9-49 n 48 63ooo6 io-63o337 5o- ii 9- 358o64 8- 98 9.988401 ■49 9.369663 % 12 3586o3 8-97 988371 ■49 370232 9.46 629768 i3 3D9141 8-96 988342 •49 370799 9-45 629201 628633 47 14 359678 8-g5 9 883 1 2 .50 371367 9-44 46 l5 36o2i5 8-93 988282 .50 371933 9-43 628067 45 16 360752 8-92 988252 .50 372499 9-42 627501 U \l 361287 8-91 988223 .50 373o64 9-4r 626o36 626371 43 361822 h; 988193 -50 373629 940 42 '9 362356 988163 -50 374193 Hi 625807 41 20 362889 8-88 988i33 • 50 374716 626244 40 21 9-363422 8-87 9.988103 .50 9.370319 9- 3 7 10-624681 ll 22 363 9 54 8-85 988073 •50 373881 9-35 6241 19 623558 23 364485 8-84 988043 •5o 376442 9-34 37 24 25 365cn6 365546 8-83 8-82 988013 987983 -50 •50 377003 377563 9-33 9-32 622997 6224.37 621878 36 35 26 366075 8- 81 987953 •50 378122 9-3i 34 ll 366604 8-8o 987922 -50 378681 9-3o 621319 33 367131 8-79 987892 .50 379239 9-29 620761 32 ?9 367659 368i85 8-77 987862 •50 379797 .38o354 9-28 620203 3i 3o 8-76 987832 •51 9-27 9-26 619646 3o 3i 9-368711 8-75 9.987801 ■51 9.380910 10-619090 6i8534 29 32 369236 8-74 987771 •51 38i466 9-25 28 33 369761 8-73 987740 •5i 382020 9-24 617980 ll 34 370285 8-72 987710 ■51 382575 9-23 617425 35 370808 8-71 987679 ■51 383129 9-22 616871 25 36 37i33o 8-70 987649 •51 383682 9-21 6i63i8 24 ll 371852 869 987618 ■51 384234 9-20 61 5 7 66 23 372373 8.67 987588 •5i 384786 9-io 610214 22 39 372894 8-66 987557 • 51 385337 385888 9-i8 614663 21 4o 373414 8-65 987526 ■5i 9-17 614112 20 4i 9.373933 8-64 9-987496 •51 9-386438 9-i5 io-6i3562 s 42 - 374452 8-63 987465 •51 ,386987 387M6 388o84 9-14 6i3oi3 43 374970 375487 376003 8-62 937434 ! ■51 9- 13 612464 \l 44 8-6i 987403 ■ 52 9- 12 611916 611J69 45 8-6o 987372, •52 388631 9-n i5 46 3 7 65io 8-5 9 98^341 •52 389118 9-10 610822 14 47 48 377035 8-58 987310 •52 389724 9.09 610276 i3 377549 378063 8-57 8-56 987279 987248, ■52 • 52 390270 390815 9-08 9-07 _ 609730 '609183 12 11 5o 378577 8-54 987217 •52 391360 9.06 608640 IC 5i 9-379089 8-53 9-987186 •52 9*391903 9-o5 10-608097 Q 52 379601 8-52 987155. •52 392447 9.04 607533 8 53 3Son3 8-5i 1 987124 ■52 392989 39353i 9-o3 60701 1 606469 7 54 380624 8-5o 987092. ■52 9-02 6 55 38n34 8-40 987061 •52 394073 9-01 605927 5 56 38i643 8-48 987030I . 986998; •52 394614 9 00 8.99 6o5386 4 ll 382152 8-47 •52 395i54 604846 3 382661 8-46 986967, 986936 ' ■52 395694 8-98 604306 2 , ?9 383 168 8-45 • 5a| . 3cp&!33 8-07 603767 1 00 383675 8-44 j -,986904 •52J 396771 8-96 6o322g| Cosine D. BSpe 76° 1 Cotaiig. D. Tanj2 ll.^ 82 (14 DEGREES.) A TABLE OP LOGARITHMIC M. Bine D. Cosine j D- Tsui£. D. Cotnng. 9-3836-5 8-44 9-986904 •52 9-396771 8-96 10-603229 60 I 384ib2 *8 43 986873 •53 397309 8- 9 6 602691 602134 u 2 384687 8 42 986841 •53 397846 8- 9 5 3 385ig2 8 41 986809 •53 3 9 8383 8-94 601617 % 4 3856 9 7 8 40 986778 ■53 398919 399455 8- 9 3 601081 56 5 386201 8 \l 986746 •53 8-92 6oo545 55 6 386704 8 986714 ■53 399990 4oo524 8-91 600010 54 I 387207 8 37 986683 ■53 8-90 8-89 8-88 599476 53 387709 388210 8 36 986651 ■53 4oio58 598942 52 9 8 35 986619 •53 40 1 591 598409 597876 5i 10 3887 1 1 8 34 ■ 986587 •53 402 1 24 8-87 5o II 9-389211 8 33 9-9%555 ■53 9-402656 8-86 10-597344 % 12 3897 1 j 8 32 9 86523 •53 4o3i87 403718 -8-85 596813 ■3 390210 8 3i 986491 986459 •53 8-84 596282 % 14 390708 8 3o •53 404249 404778 8-83 695751 i5 391206 8 28 , 86427 ■53 8-82 595222 45 16 391703 8 27 986395 •53 4o53o8 8-8i 594692 44 ;; 392199 392693 8 26 9 86363 ■54 4o5836 8-8o 564164 43 8 25 98633i •54 4o6364 8-70 8-78 5 9 3636 42 "9 3g3iqi 8 24 % 986299 ■54 406892 593108 41 20 3g3685 8 23 986266 ■54 407419 9-407945 408471 8-77 592581 40 21 9-394170 394673 8 22 9-986234 ■54 8-76 10-592055 3o 22 8 21 9%202 •54 8-75 591529 59100J 38 23 3o5i66 8 20 986169 •54 408997 409521 8-74 37 24 3 9 5658 8 19 986137 ■54 %'H 590479 589955 36 25 396150 8 18 9% 1 04 9%072 ■54 410045 8-73 35 26 396641 8 17 • 54 410569 8-72 58o43 1 34 3 397132 8 \l 986039 ■ 54 41 1092 8.71 588908 33 397621 3981 1 1 8 986007 ■54 4n6i5 8-70 588385 32 2 9 8 i5 983974 • 54 4i2i3t 412658 8-69 58 7 863 3i 3o 39S600 8 14 9S5942 •54 8-68 58t342 3o 3i 9-399088 8 13 9-9S5909 985876 • 55 9-4i3i79 8-67 10-586821 It 32 399575 8 12 • 55 413699 8-66 5863oi 33 400062 8 11 " 985843 .55 414219 8-65 585 7 8i 11 34 400549 4oio35 8 10 9 858i 1 • 55 414738 8-64 585262 35 8 09 985778 •55 4i5257 8-64 584743 25 36 40 1 520 8 08 985745 • 55 415775 8-63 584225 24 u 40200D 8 07 985712 • 55 416293 8-62 583707 23 402489 8 06 985679 • 55 416810 8-61 583 1 90 22 3 9 402972 8 o5 9 85646 • 55 417326 8-6o 582674 21 40 403455 8 04 980613 ■ 55 417842 9-418358 8-5 9 8-58 582i58 20 41 9-4o3938 8 o3 9-985580 • 55 io-58i642 \l 42 404420 8 02 985547 ■ 55 418873 8- 5 7 581127 43 404901 8 01 985014 ■55 419387 8-56 58o6i3 \l 44 4o5382 8 00 985480 •55 419901 8-55 580099 45 4o5862 7 3 935447 •55 420415 8-55 579585 i5 46 4o634i 7 985414 • 56 420927 8-54 579073 578560 14 % 406820 7 97 98538o •56 421440 8-,53 13 407299 7 96 ■ 985347 -56 421962 8-52 578048 12 & 407777 7 9 3 9853 1 4 ■56 422463 8-5i 577537 11 5o 408254 7 94 985280 • 56 422974 8-5o 577026 10 5i 9 408731 7 94 9-985247 985213 • 56 9-423484 8.40 10-576516 I 53 409207 7 9 3 •56 423993 4245o3 8-48 576007 53 409682 7 92 985i8o ■56 8 48 575497 574989 1 54 410157 7 9 1 985146 ■56 425ou 8-47 8-46 6 55 4io632 7 90 gS5n3 •56 425519 574481 5 56 411106 7 89 985079 985045 •56 426027 8-45 573973 4 §2 411579 7 88 ■56 426534 8- 44 573466 3 412052 7 87 98501 1 ■56 427041 8-43 572959 572453 2 5, 412524 7 86 984978 ■56 427647 428o52 8-43 1 60 412996 7 85 984944 56 8-42 5719481 _- Oosine D. Sine IT 5° Cotang. I). "fiii^n m. SINES AND TANOENTS. (15 DEGREES. ) 9? k Sine D. I Cosine [ D. Tang. D. Cotang 9-412996 7-85 9-984944] •57 9-428032 8 42 10-571948 60 I 413467 V 84 984910 984876 .37 428557 8 41 571443 18 2. 4i3938 7 83 'V 429062 8 40 570938 3 414408 7 83 984842 - •57 429366 8 39 570434 ll 4 414878 7 82 984808 'V 430070 '8 38 569930 5 416347 4i58i5 7 81 984774 I 7 43o573 8 38 569427 55 6 7 80. 984740 •57 431075 8 ll 568925 54 I 416283 7 71 , 084706 'V 43i577 8" 568423 53 416751 7 984672 9846J7 ' 98460J ■57 432079 43258o 8 35 567921 52 9 417217 7 77 •37 8 34 567420 5i 10 417684 7 76 ■57 433o8o 8 33 566920 5o It 9'4ioi5o 7 75 9.984569 ■37 9-433586 8 32 10-566420 % 12 4i86i5 7 74 984530 •37 434o8o 8 32 565920 i3 419079 7 73 984500 i 7 434579 435078 8 3i 565421 s-. 14 419544 7 73 984466 :U 8 3o 564922 i5 420007 7 7^ 084432 435576 8 29 564424 45 16 420470 7 71 984397 ■58 436073 8 28 563927 44 !3 42oq33 42i3o5 7 70 984363 ■58 436570 8 28 56343o 43 7 & 984328 ■58 437067 437563 8 ll 562933 42 '9 421837 4223i8 7 984294 ■58 8 562437 41 20 7 67 984259 ■58 438o59 8 25 561941 40 21 9-422778 7 67 9-984224 • 58 9.438554 8 24 io-56i446 ll 22 423238 7 66 9«4i9? •58 439048 8 23 560952 23 42%97 7 65 984155 ■58 439543 8 23 56o457 ll 24 424106 7 64 984120 • 58 44oo36 8 22 559964 25 4246i5 7 63 984085 •58 440529 8 21 559471 558978 558486 35 26 426073 7 62 984050 •58 441022 8 20 3-C 3 42553o 7 61 984015 • 58 44i5i4 8 '9 33 420987 7 60 9 83 9 8i • 58 442006 8 19 557994 557Do3 .32 29 426443 7 60 983946 ■58 442497 442988 8 iJ 3l 3o 426899 9-427334 7 3 98391 1 ■58 8 17 557012 io- 556521 3o 3i 7 9-983875 • 58 9-443479 .8 16 ll 32 427809 428263 7 57 983840 I 9 443968 8 16 556o32 33 7 56 9 838o5 I 9 444458 8 i5 555542 21 34 428717 7 55 983770 9 83 7 35 .59 444947 - 8 14 555o53 26 ,35 429170 7 54 I 9 445435 8 i3 554565 25 36 429623 7 53 • 983700 9 83664 I 9 446923 8 12 554077 553589 24 33 43oo75 7 52 I 9 44641 1 8 12 23 43o527 430978 7 52 983629 I 9 446898 8 11 553io2 22 3 9 7 5i 9 835 9 4 I 9 447384 8 10 562616 21 40 '431429 7 5o 9 83558 I 9 447870 8 09 552i3o 20 41 9-431879 7 ■49 9.983523 ■ 5 9 9-448356 8 09 io-55i644 18 42 432329 7 •49 983487 P 448841 8 08 55u59 43 432778 7 .48 983452 I 9 449326 8 07 550674 17 44 433226 7 :% 983416 I 9 449S10 8 06 550190 16 45 433675 7 9 8338i -5 9 430294 8 06 549706 i5 46 434122 7 ■45 983345 I 9 400777 8 o5 540223 14 % 434569 7 •44 983309 • 5 9 461260 8 04 548740 13 435oio 7 .44 9 832 7 3 •60 45i743 8 o3 648267 547776 12 49 435462 7 •43 9H3238 .60 452225 8 62 11 5c 435oo8 9-436353 436798 7 ■42 983202 •60 452706 8 02 547294 10 5i 7 41 9-983166 • 60 9-453187 453668 8 01 io-5468i3 8 52 7 ■40 983 i3o • 60 8 00 546332 , 53 437242 7 •40 983094 983o58 ■60 454148 7 99 545852 7 54 43 7686 438129 438572 7 •39 • 60 454628 7 3 545372 6 55 7 ■ 38 983022 • 60 455i07 7 544893 5 56 7 ■37 982986 • 6o 455586 7 97 5444i4 4 % 439014 439456 7 ■36 982950 •60 456064 7 9 6 543936 ,3 7 • 36 982914 982878 ■ 60 456542 7 t 543458 2 ss 439897 44o338 7 -35 ■60 457019 457496 7 9 5 542981 542604 _ TangT 1 7 •34 982841 ■ 60 7-9* M. Cosine D. Sine 74° Cotang. ■ J D. u (16 DEGREES.) A TABLE OF LOGARITHMIC M. Sine I D. Cosine I). Tung. D- Coltmg. 9-44o338| 7-34 9-982842 -6o 9-457496 7-94 Io-54?5o4 60 I 440778I 7-33 982805 -60 , 457973 7- 9 3 542027 5 9 2 441218 7-32 982769 982733 ■ 61 458449 458925 7- 9 3 54i55i 58 3 441658 7-3i • 61 7.92 541075 57 4 442096; 7 - 3 1 982696 • bi 459400 7-91 . 540600 56 5 442535 7'3o 982660 • 61 459875 7-90 540125 55 6 442973 ]:% 982624 ■61 46o349 7.90 ?:8 53 9 65i 54 'I 443410 982587 ■61 460823 530177 53o7o3 53 443847 7-27 982551 •61 461297 52 i 9 444284 7-27 982514 •61 461770 7.88 53823o 5i 10 444720 7-26 982477 •61 462242 7-87 537758 5o n 9'445i55 7-25 0-982441 •61 9-462714 7.86 10-537286 49 12 445590 7-24 982404 •61 463 1 86 7-85 5368i4 48 13 446025 7-23 982367 •61 463658 7-85 536342 47 U 44645o 446893 7-23 982331 •61 464129 7.84 5358 7 i 46 i5 7-22 982294 982257 •61 464599 7-83 5354oi 45 16 447326 7-21 •61 465069 7-83 534931 44 \l 447759 448191 7-20 982220 •62 46553o 466008 7.82 53446i 43 7-20 982 i83- •62 7.81 533992 533524 42 '9 448623 7- 19 982146 ■62 466476 7.80 41 20 449054 7- 18 982109 ■62 466945 7-80 533o55 4o 21 9-449485 7-ij 9-982672 ■62 9-467413 7-79 io-53258 7 IS 22 449915 45o345 7.10 982035 ■62 467880 7-78 532120 23 7. .6 981998 •62 468347 7-78 53i653 ll U 450775 7 -i5 981961 • 62 468814 7-77 53n86 25 45 1 204 7-U 981924 981886 ■62 469280 7-76 530730 35 26 45i632 7. .3 ■62 469746 7.75 530254 34 27 452o6o 7-13 981849 •62 4702 1 1 7-75 - 529789 33 28 452488 7-12 981812 •62 470676 7-74 529324 32 I 9 ' 452915 7-n 981774 ■62 471141 7-73 52885 9 3i 3o- 453342 7-10 981737 ■62 471605 7.73 5283o5 10-527932 3o 3i 9-453768 7-10 9-981699 ■63 9-472068 7.72 3 32 454194 7.09 7-08 981662 •63 472532 7-71 527468 33 454619 981625 •63 472995 473457 7.71 527005 27 34 455o44 7-07 '981587 ■63 7-70 '526543 26 35 455469 455893 7-07 981549 ■63 473919 7-69 526081 25 36 7-06 981512 •63 47438i 7.69 5256iq 24 jiz 4563 1 6 7-o5 981474 •63 474842 r bl 5a5i58 23 '456739 7-04 981436 •63 4753o3 7-67 524697 5242J7 22 1 39 457162. 7-04 981399 •63 475763 7*7 2C 40 45J584 9- 458oo6 7-o3 981361 ■63 476223 7-66 523777 20 41 7-02 9-98i323 •63 9-476683 7-65 io-52.33i7 3 42 458427 458848 7-01 .'981285 •63 477142 7-65 522858 43 7-01 981247 •63 477601 7-64 522399 n 44 459268 7-00 981209 ■63 478059 7-63 521941 16 45 459688 6.90 981 171 ■63 478517 7-63 521483 i5 46 460108 6.9I 981 i33 •64 478975 7-62 521025 14 2 460527 460946 -461J64 6-98 981095 98i'o57 ■64 479432 7-61 520568 i3 6-97 6-96 •64 479889 480346 7.61 5201 11 12 49 981019 .64 7-60 519655 11 5o 461782 6- 9 5 980981 •64 480801 7-69 10-518743 10 5i 9-462199 6- 9 5 9-980942 • 64 9-481257 ]il 8 52 462616 6-94 980904 •64 481712 518288 53 463o32 6-o3 980866 ■64 482167 7-5 7 5i 7 833 7 54 463448 6- 9 3 980827 -64 482621 7-57 517379 516925 6 55 463864 6-92 980789 •64 483075 7-56 5 56 464279 6-91 980750 -64 483529 7-55 5 i 647 1 4 u 464694 6-90 980712 -64 483982 7-55 5i6oi8 3 465 1 08 6-90 .980673 ■64 484435 7-54 5i5565 a & 465522 6.89 6-88 980635 •64 484887 7-53 5i5u3 1 60 463935 980596 •64 485339 t-53 5i466i a . Oosiue D. Sine ■ '3° Cotang. tt , Tang. mT SINKS AND TANGENTS. (17 DEGREES.' 3a f5T o i Sine D. Cosine D. -64 Tang. : 9 -485339 D. Cotang. 1 10-014661 9-465o35 466348 6-88 9-980596 980558 7-55 60 11 I 6-88 ■64 485791 7-52 514209 2 466761 6-87 980519 •65 486242 7 .5. 5i3758 3 467173 6-86 980480 ■ 65 -, 486693 7-5i 5 1 33o7 5o 4 467585 6-85 980442 • 65 487143 7 00 512857 467996 468407 6-85 980403 • 65 487593 488043 7-49 512407 55 6 6-84 980364 -65 7.4a 7.48 51195-7 5ii5o8 54 53 52 5i 5o 2 468817 6-83 980325 ■65 488492 469227 6-83 980286 • 65 488941 7-47 5no59 9 469637 6-82 980247 980208 ■65 489390 489838 7-47 5io6io 10 470046 . 6-8i • 65 7.46 5ioi62 ii , 9-470455 6-8o 9-980169 ■ 65 9-490286 7.46 10*509714 49 12 470863 6-8o 980130 ■ 65 490733 7.45 609267 48 13 471271 6-79 980091 • 65 491180 7-44 5o882o 47 U 471679 6-78 980002 •65 491627 7.44 5o8373 46 45 i5 472086 6-78 980012 • 65 492073 7-43 507927 16 472492 6-77 979973 •65 492519 7-43 507481 44 43 15 472898 6-76 979934 979895 97 9 855 ■66 492965 7-42 5o7o35 473304 6-76 ■ 66 493410 7-41 506590 42 '9 473710 6-75 ■66 493854 7-40 5o6i46 41 20 4741 1 5 6-74 979816 ■ 66 494299 7.40 5o570i 40 39 38 21 9-474510 474923 475327 6-74 9-979776 .66 9-494743 7-40 Io-5o5257 22 6-73 979737 • 66 490186 7-3g 504814 23 6-72 979608 ■ 66 4g563o 7-38 504370 ll 35 24 475730 6-72 ■ 66 496973 • 7-37 503927 25 476i33 6-71 979618 ■ 66 4965 1 5 7-37 5o3485 26 476536 6-70 6-69 979579 ■ 66 496957 7-36 5o3o43 34 33 32 3i 3o a 476o38 979539 ■ 66 497399 7-36 5o26oi 477340 6-69 6-68 979^99 979459 ■ 66 497841 7-35 5o2i5o ?9 477741 478142 ■ 66 498282 7-34 501718 3o 6-67 979420 ■ 66 498722 7-34 501278 3i 9-478542 6-67 9-979380 ■ 66 9-499163 7-33 io-5oo837 2I 32 478942 479342 6-66 979340 • 66 499603 7-33 5oo3g-7 499908 499019 33 6-65 979300 .67 5ooo42 7.32 % 34 479741 480140 6-65 979260 -67 5oo48i 7-3i 35 6-64 979220 •67 500920 5oi359 7-3i 499080 2D 36 48o539 6-63 979180 •67 7-3o 498641 24 23' 22 12 486-937 48i334 6-63 6-62 979140 979 1 00 .67 .67 501797 5o2235 7-3o 7-29 498203 497765 3 9 481731 6-6i 979059 •67 502672 7.28 497328 21 40 482128 6-6i 979019 9-978979 • 67 5o3l09 7-28 496801 10-496404 20 41 9-482525 6-6o .67 9 -5o3546 7-27 \% 42 482921 4833 1 6 6-59 978935 ■ 67 ■ 503982 7 " 2 I 496018 ••43 6-5 9 6-58 97889^ 978858 •67 5o44i8 7.26 495582 17 16 15 44 483712 .67 5o4854 7 . 2 5 495l46 45 484107 6-57 978817 .67 505289 7-25 49471 1 46 4845oi 6-57 978777 .67 5x>5724 7-24 494276 14 i3 % 484895 6-56 978736 ■67 5o6i5o 506590 7-24 493841 485289 6-55 978696 m 7-23 493407 12 49 485682 6-55 978655 • 68 507027 ■ 7-22 492973 492040 11 5o 486075 6-54 978615 ■ 68 507460 7-?2 10 5i 9-486467 6-53 9-9785-74 • 68 9-507893 5o8326 7-2! 10-492107 % 52 486860 6-53 , 97853: • 68 7-21 491674 53 487251 6-52 97849.3 978452 •68 508759 7-20 491 241 I 5 54 487643 488o34 6-5i ■•68 509191 7-19 49080c 55 6-5i 97841 1 • 68 509622 7-18 7-18 49037* 489946 4890 1 5 56 488424 488814 6-5o 6-5o 97837c 97832c ■ 68 -68 5ioo54 5 1 o485 4 3 48920^ 489093 489982 6-49 6-48 -6-48 97828* ■97824-, .97820c ■68 ■ 68 ■68 5iooi6 5n346 011776 ■7.17 7-16 7-16 489084 4«8654 488224 2 1 Cosine D. Sine IT2° CoUmg. ' ll 1 Tang- _M. 36 (18 DEGREES.) A TABLE OF LOGARITHMIC 1 m i| M. Sine D. Cosine i 1>- Tang. D. Cotauft. 9-489982 49037 i 6-48 9-918206! -68 9-511776 7 16 10-488224 60 6 48 978165 68 512206 7 16 487794 11 n i 490739 6 40 -978124; 68 512635 7 i5 487365 3 491 i47 491535 6 978083; 69 5 1 3064 7 14 486o36 4 6 46 978042! 69 5 13493 7 14 486607 5 491922 492308 6 45 978001 1 69 5i3o2i 514349 7 i3 486079 55 6' 6 44 977959 69 7 i3 48565i 54 3 492695 6 44 977918 977077 69 514777 7 12 485223 53 493081 6 43 69 516204 7 12 484796 484369 483943 52 9 493466 6 42 977835 69 5i563i 7 11 5i 10 49385i 6 42 977794 9.977752 69 5 1 6057 7 10 5o ii 9 '494236 6 41 69 9.516484 7 10 io-4835i6 49 12 494621 6 41 9777" 69 516910 5i7335 7 09 483090 48 i3 495oo5 6 40 977669 977628 69 7 00 482666 47 U 495388 6 3 9 69 517761 . 5i8i85 7 482239 46 i5 495772 6 ll 977586 69 7 08 48i8i5 45 16 496154 6 977544 70 5i86i 7 07 481390 44 ■7 496537 6 37 9775o3 70 519034 7 06 480966 480042 43 18 496919 '4973o 1 6 37, 977461 7° 5 1 9458 7 06 42 '9 6 36 977419 70 519882 7 o5 480118 4i 20 . 497682 6 36 977 3 77 70 52o3o5 7 o5 479695 40 21 9-498064 6 35 9-977335 70 9.520728 7 04 10-470272 4-18849 3 9 22 498444 6 34 977293 70 521 I 5 T 7 o3 38 l3 498825 6 34 977201 70 021573 7 o3 478427 37 14 499204 6 33 977209 70 521995 7 o3 478006 36 i5 499584 6 32 977167 977125 70 622417 7 02 477583 35 16 499963 6 32 70 522838 7 02 477162 34 s 5oo342 6 3! 977083 70 52325 Q 7 01 476741 33 500721 6 3i 977041 70 523686 7 01 476320 32 ! 9 501099 6 3o 976999 976957 7° 524100 7 00 476900 3i lo 501476 6 29 70 52452o 6 99 475480 3o Ii 9-5oi854 6 3 9-976914 976872 976830 70 9-524939 52535q 525778 6 3 10-475061 20 12 502231 6 71 6 474641 !3 502607 6 28 7 1 6 98 4742'22 27 U 502984 6 27 976787 976745 T 526197 6 97 4738o3 26 \5 5o336o 6 26 7> 5266i5 6 9 Z 96 473385 25 16 5o3735 6 26 976702 71 527033 6 472967 472649 24 ii 5o4no 6 25 976660 71 52745i 6 t 23 5o4485 6 25 976617 71 527868 528285 6 9 5 472132 22 i? 504860 6 24 976574 7 1 6 9 5 471716 21 to 5o5234 6 23 976532 7 1 528702 6 94 471298 20 ii 9-5o56o8 6 23 9-976489 7> 9-529119 52 9 535 6 9 3 10-470881 lo (2 5o5o8i 5o6354 6 22 976446 7' 6 9 3 470465 10 43 6 22 976404 71 529950 53o366 6 9 3 47oo5o 'I 44 606727 6 21 976361 '/' 6 92 - 469634 16 45 507099 6 20 6 7 63i8 T 530781 6 9' 469219 468804 i5 46 507471 6 20 976275 7' 531196 6 9' 14 % 607843 5o82i4 6 '9 9762J2 72 53i6u 6 90 46838o 467970 467661 i3 6 976189 976146 72 532025 6 90 12 49 5o8585 6 l8 72 532439 532853 6 §9 11 5o 5o8o56 9.509.326 6 18 976103 72 6 §8 467147 10 5i 6 17 9.976060 72 9-533266 6 10-466734 52 509696 6 16 976017 72 533679 6 88 466321 53 5ioo65 6 16 975974 72 534092 6 |7 465908 7 54 5 1 o434 6 i5 975o3o 72 534304 6 oo 466496 465o84 6 55 5io8o3 6 i5 975887 72 534916 535328 6 5 56 511172 6 14 975844 72 6 86 464672 4 u 5u54o 6 i3 975800 72 535739 6 85 464261 3 511907 6 i3 975757 72 536 1 5o 6 S5 46385o 2 5 9 5i2275 6 12 975714 72 53656i 6 84 46343o 463028 1 66 5i:642 6 12 975670 72 536972 6 84 r Cosine D. Bine 710 Cotang. D. Tang. M. BINES AND TANGENTS. (19 DEGRESS.) 37 M. Sine D. Cosine D. Tang. D. Cotang. 1 9.512642 6-12 9.975670 ■73 9.536972 537382 6-84 10-463028 60 i 5i3oog 5i33p 6- 1 1 975627 •73 6-83 462618 5 9 2 6-U 975583 ■73 537792 538202 6-83 462208 58 3 5i374i 6-io 975539 •73 -6-82 461798 461389 h 4 514107 6-09 975496 973452 ■73 5386i 1 6-82 56 5 514472 6-09 ■73 539020 6-8i 460980 460671 55 6 5i4837 6-08 975408 ■73 539429 6-8i 54 I 5l5202 6-o8 9 7 5365 •73 539837 540245 6-8o 460163 53 5i5566 6-07 975321 •73 6-8o /i59755 52 9 5i593o 6-07 ' 6-06 975277 975233 ■73 540653 6-79 45q347 5i IO 5 1 6294 9.516667 517020 ■73 54 1 06 1 6-70 458939 10 -458532 5o II 6-o5 9.975189 •73 9-541468 6-78 % 12 6-o5 9l5i45 •73 541875 542281 6-78 458125 i3 517382 6-o4 975101 •73 6-77 457719 47 14 517745 518107 518468 6-o4 975o57 •73 542688 6-77 4573i2 46 i5 6-o3 975oi3 ■73 543094 6-76 456906 4565oi 45 16 6-o3 974969 •74 543499 6-76 44 \l 518829 6-02. 974925 ■74 543900 5443io 6-75 406095 43 519190 5i955i 6-oi 974880 •74 6-75 4556oo 42 i 9 6-oi 974836 •74 5447i5 6-74 455285 41 20 519911 6-oo 97479 2 •74 545119 6-74 45488i 4o 21 9.520271 52o63i 6.oo 9'-974748 •74 9.545524 b -l\ 10-454476 38 22 5-99 ) 9747^3 •74 545928 6-73 454072 23 .520990 5-99 974609 •74 54633 1 6-72 45366n 453265 ll * 24 521349 5-98 974614 •74 546735 6-72 25 521707 5- 9 8 974570 •74 547i3S 6-71 452862 35 26 522066 5-97 974D25 ■74 547540 6-71 452460 34 11 522424 5-96 974481 ■74 547943 548345 6-70 452057 33 622781 5- 9 6 974436 ■74 6-70 45 i 655 32 20 523i38 5- 9 5 974391 ■74 548747 6-69 45 1 253 3i 3o 5234o5 9.523832 524208 5- 9 5 974347 ■75 549 1 49 6-69 45o85i 3o 3i 5-94 9-974302 ■75 9 ■ 549550 6-68 io«45o45o 18 32 5- 9 4 ' - 974 2 57 •75 549o5 1 55o352 6-68 45ao4o 449648 33 524564 5- 9 3 974212 •75 6-67 27 34 35 524920 52J275 5- 9 3 5-92 974167 974122 •75 •75 550752 55n52 6-67 6-66 449248 448848 26 25 36 52563o 5-91 974077 •75 55 1 552 6-66 448448 24 12 525o84 52633o 526693 5-91 5-90 974032 973987 ■75 ■75 55io52 55235i 6-65 6-65 448048 4*47649 23 22 3 9 5.90 5-8 9 973942 ■75 552750 6-65 44725o 21 40 527046 973897 ■75 553 1 49 9-553548 553o46 554344 6-64 446851 20 42 43 9.527400 527753 528io5 5-8 9 5-88 5-88 9-973852 973807 973761 ■75 ■75 •75 6-64 6-63 6-63 IO-446452 446o54 445656 !8 '1 44 528458 5-87 973716 •76 554741 6-62 445259 16 45 528810 5-8 7 973671 •76 555 1 39 6-62 444861 i5 46 529161 5295i3 529864 5-86 973625 •76 555536 6-61 444464 14 % 5-86 5-85 973580 973535 ■76 .76 555o33 55632c 556721 6-6i 6-6o . 444067 443671 i3 12 40 53o2i5 5-85 973489 .76 6-6o 443275 11 5o 53o565 5-84 973444 ■76 557121 6-59 442870 10 5i 9. 53o9i5 531265 5.84 9-973398 •76 9.557517 6-59 IO-442483 8 52 5-83 97 3352 .76 557913 5583o8 6-5o 6-58 442087 53 53i6i4 5.82 973307 .76 441692 54 53io63 532312 5-82 • 973261 .76 ■ 558702 6-58 441298 55 5-8i 9732i5 -76 M9097 6-57 440903 5 56, 532661 5.8i 973169 .76 559491 55 9 885 6-57 440009 4401 15 4 3 5? 533009 533357 533704 534o52 . 5- 80 973124. .76 6-56 58 60 5. So 5.78 973078 973o32 972986 .76 ■77 •77 66027c 56067' 56io66 6-56 6-55 6-55 439721 43o327 438934 2 1 Cosine ]>. Sine T0° Cotang. D. Tang. M. 38 (20 DEGREES.) A TAB1E OF LOGARITHMIC M. Sine D. 12 i3 U yl5 16 19 20 21 22 23 24 25 26 ?9 3o 3i 3a .33 .34 35 36 §3 3 9 40 •n 42 43 44 45 46 % £ 5i 52 53 54 55 56 33 2S )• 534032 534399 034745 535og2 535437 ' 578853 5i3 966292 .86 6i256i 6 00 43 18 579162 5-i3 966240 .86 6 1 292 1 6 00 3870791 42 '9 579470 5-i3 966188 .86 6i328i 5 99 386719I 41 20 579777 5-12 966 1 36 .86 6i364i 5 9? 38635g| 40 21 ^•58oo85 5-12 9-966085 .87 9.614000 5 98 ro-386ooo ?? 22 580392 5-ii 966033 •87 6143D9 5 9 £ 385641 38 ~ 23 580690 58ioo5 5- 11 963981 ■87 614718 5 98 385282 iz 24 5-u 968928 -87 610077 5 97 384923 384565 25 58i3i2 5-io 965876 •87 6i5435 5 97 35 26 58i6i8 5-io 965824 •87 616793 616101 5 97 384207 34 s 581924 5-09 965772 •87 5 96 383849 33 582229 5-09 965720 .87 616509 5 t 383491 383i33 32 29 58253d 5.09 96 5668 •87 616867 5 96 3i 3o 582840 5-o8 9656i5 •87 617224 5 9 3 3S2776 3o 3i 9-583i45 5-o8 9-965563 .87 9-617582 5 ^ 10-382418 3 32 583449 5-07 9655i 1 .87 . 617939 618295 5 9 5 382061 33 583754 5.07 5-o6 9 65458 •87 5 94 381706 11 34 584o58 965406 .87 618662 5 94 38i348 35 58436i 5-o6 .965353 .88 619008 5 94 380992 38o636 25 36 584665 5-o6 9653oi .88 619364 5 9 3 24 32 584968 5-o5 965248 .88 619721 5 93 380279 23 585272 5-o5 965:95 .88 620076 620432 5 9 3 379924 379668 22 -3 9 5855 7 4 5-o4 965i43 .88 5 92 21 40 585877 5-o4 965090 9-965037 .88 620787 5 9? 379213 20 41 9-586179 586482 5-o3 .88 9-621142 5 92 10-378858 "18 42 5-o3 964984 .88 621497 5 9' 378603 43 586783 5-o3 964931 .88 621802 5 9' 3 7 8 U8 '7 44 587085 5-02_ 964879 964826 .88 622207 5 90 377793 377439 377085 16 45 58 7 386 5-02 .88 622661 5 90 i5 46 587.688 5-oi 964773 .88 622916 5 90 14 % 587989 588289 5-oi 964719 .88 623269 623623 5 89 376731 i3 5-01 964666 .89 5 ^ 376377 12 49 588590 5-oo 964613 .89 623976 5 89 376024 11 5o 5888go 5-oo 964560 .89 62433o 5 88 375670 10 5i 9-589190 589489 4-99 9-964507 .89! 9-624683 5 88 10-375317 3 52 4-99 964454 .89! 625o36 5 88 374964 53 589789 4-99 964400 .89 625388 5 87 ■374612 7 54 590088 4.98 964347 ■ 8 9 626741 5 87 374259 6 55 590387 4 . 9 8 . 964294 .89 626093 • 5 SZ 373907 5 56 590686 4-97 964240 -8q 626445 5 373555 4 u 590984 ' 4-97 964187 .89 626797 5 86 373203 3 591282 4-97 4-96 964133 •89 627149 5 86 37285.1 2 59 59i58o 964080 .89 627001 5 85 372499 372148 1 60 591878 4.96 964026 ■8gl 627852 5 85 M. Cosine D. Sine G7°l Ootang. D. Tang. BINES AND TANGENTS. (23 DEGREES.] 41 '&. Sine 13. Cosine | D. Tang. D. Cotang. 60 0-591878 4.96 9 • 964026 S 9 9-627802 5 85 10-372148 I 592176 4 9 5 963972 89 628203 5 85 371797 31 1 592473 4 95 9639 1 9 89 628554 ' 5 85 371446 3 592770 4 95 963863 90 628905 5 84 371095 p 4 593067 593363 4 94 9b38n 90 629255 5 84 370745 370394 56 5 4 94 963757 90 629606 5 83 55 6 593659 593900 4 93 963704 90 629956 5 83 370044 54 3 4 93 . 963630 9c 63o3o6 5 83 369694 53 59420 1 4 ,3 * 9635961 90 6'3o6S6 5 83 369344 52 9 594547 4 9 2 963542 90 63ioo5 . 5 82 368996 5i 10 594842 4 9 : 963488 9 c .63i355 5 82 368645 5o u q.590137 4 9 1 9-963434 90 9-631704 5 82 10-368296 % 12 595432 4 9 1 963379 90 632053 • 5 81 367947 i3 595727 4 91 963323 90 632401 5 81 367399 47 U 596021 4 90 963271 90 63275o 5 81 - 367230 46 i5 5963i5 4 s 963217 963 1 63 90 633098 5 80 366902. 45 16 596609 4 90 633447 5 80 366653 44 \l 69690.3 4 89 963 1 08 9' 633796 5 80 366203 43 597196 4 89 963054 9' 634U3 5 79 365857 42 '9 597490 597783 g. 59807 5 4 88 962999 962945 9i 634490 634838 5 79 3655io 41 20 4 88 9" 5 I 365 162 40 21 4 87 9-962890 9i 9-635i85 5 10O64815 % 22 5 9 3368 4 87 962836 9 1 635532 5 i 364468 23 698660 4 87 '962781 9 1 635879 5 78 364i 21 37 24. 598952 4 86 962727 9 1 636226 5 77 363774 36 25 599244 4 86 962672 9 1 6365 7 2 5 77 363428 35 26 599536 4 85 962617 9 1 636919 5 77 363o8i 34 3 599827 600118 4 85 962562 9' 637265 5 77 362735 33 4 85 962508 9' 637611 5 76 362389 32 29 600409 4 84 962453 9 1 63to56 5 76 362044 3i 3o 600700 4 84 962398 9 2 638302 5 76 361698 3o 3i 9.600990 4 84 9-962343 92 9-638647 5 75 io-36i353 3 32 601280 4 83 962288 92 63S992 5 75 361008 33 69-1 570 4 83 962233 92 63*9337 5 7 5 36o663 27 34 601860 4 82 / 962178 -92 639682 5 74 36o3i8 26 35 602 1 5o 4 82 962 1 23 92 640027 5 74 359973 25 36 602439 4 82 962067 92 640371 ,5 74 359629 24 12 602720 4 81 962012 92 640716 5 73 350284 23 603017 4 81 961957 92 641060 5 73 358940 22 3 9 6o33o5 4 81 961902 92 641404 5 73 338396 21 40 603D94 • 9 .6o3882 4 80 961846 92 641747 5 72 358253 20 41 4 80 9-961791 92 9-642091 642434 5 72 10-357909 35 7 566 8 4r 604170 4 79 961735 92 5 72 43 6o4457 604745 4 79 961680 92 64.2777 5 72 357223 \l 44 4 79 961624 9 3 643 1 20 ' 5 71 35688o 45 6o5o32 4 78 961569 93 643463 5 71 356537 i5 46 6o53r9 4 78 g6i5i3 9 3 6438o6 5 7' 356194 14 % 6o56oo 4 78 961458 93 644148 5 70 355832 i3 605892 4 77 961402 93 644490 644832 5 7° 3555 10 12 49 606179 4 77 961346 9 3 5 70 355i68 11 56 606465 4 7° 961290 9-961235 9 3 645174 5 69 354826 10 5i 9.6067.51 v .6070.36 4 76 9 3 9 -6455 16 5 69 10-354484 9 5i 4 7.6 961179 961 123 9 3 645857 5 69 354U3 8 53 607322 4 75 9 3 646199 5 69 3538oi 7 54 607607 4 75 961067 9 3 6465,40 5 68 35346o 6 55 607892 4 74 961 01 1 9 3 646881 -5 68 353iio 352778 5 56 608177 4 74 960955 9 3 647222 5 68 i ; 5% 60846 f 4 74 960899 9 3 647562 5 67 352438 i 608745 4 73 960843! 94 647903 648243 5 67 352097 1 59 ^ 609029 609313 4 73 960786' 94 5 67 351767 1 66 4 73 960730, 9i 648583 5-66 35j4i7 , . Cosine I ). .Sine Ac 6 C Cotang. D. Tung. M. 42 (24 DEGREES J A TABLE OF LOGARITHMIC Sine 1 1>. Cosine 1 «. 1 Tang. - .94 9-648583 1 !>• 5-66 Cotang. io-35i4i- 60 9-60931^ 4-73 9-960730 i 60959" 4-72 960674' -94 64892J 5-66 35ip77 It 2 6098S0 4-72 9606 it ■94 649263 5-66 33073- 3 610164 4-72 960361 •94 649602 5-66 35o3of 35oo5f 57 4 61044- 4-71 96050' ■ 94 649942 5-65 56 5 610729 4-71 960448 .94 65o2Si 5-65 349719 55 6 61 101; 4-70 960392 -94 65o62o 5-65 34938o 54 I 61 1294 4-70 96o335 •9-1 630959 5-64 349041 53 611576 4-70 960279 .94 65i2o7 65 1 636 5-64 348703 348364 52 9 6n858 4.69 960222 ■94 5-64 5! 10 612140 4.69 960163 ■94 651974 5-63 348026 5q 11 9-612421 4.69 9-960109 . 9 5 9-652312 5-63 10-347688 49 12 612702 4-68 96003; . 9 5 65265o 5-63 34i35o 48 i3 612983 4-68 939995 93993^ ■95 652o88 653326 5-63 347012 % U 6i3264 4-67 •95 5-62 346674 i5 6i3545 4-67 939883 ■ 9 5 653663 5-62 346337 45 16 6i3825 4-67 4-66 93982!: • 9 5 654ooo 5-62 346000 44 17 6i4io5 939768 •gS 634337 5-6i 345663 43 18 6i4385 4-66 9397 1 1 ■95 654674 5-6i 345326 42 '9 6 1 4665 4-66 95054 ■95 655on 5-6i 344989 41 20 61494-! 4-65 939596 .95 655348 5-6i 344652 40 21 9-613223 4-65 9-959539 • 9 5 9-655684 5-6o io-3443i6 3 9 22 6i."5o2 4-65 959482 .95 656o2o 5-6o 343980 38 23 615781 4-64 939425 .95 656356 5-6a 343644 ll 24 616060 4-64 939368 • 9 5 656692 5.59 3433o8 25 616338 4-64 939310 •96 657028 5-5 9 342972 35 26 616616 4-63 939253 .96 657364 5-5 9 342636 34 s 616894 4-63 959195 95913s .96 ' 657699 5-5 9 5-58 3423oi 33 617172 4-62 .96 658o34 341966 32 ?9 617400 4-62 959081 .96 65836 9 5-58 34i63i 3i 3o 617727 4-62 939023 .96 658704 5-58 341296 3o 3i 9.618004 4-61 9-958963 .96 9"659o3o 639373 5-58 10-340961 3 3; 6182^1 4-6i 938908 95885o .96 5-57 340627 33 6 1 8558 4-6i .96 659708 5-57 340292 339968 27 34 6i8834 - 4-6o 958792 .96 660042 5.57 26 35 619110 4-6o 938734 .96 660376 5-5 7 5.56 339624 25 36 619386 4-'o 938677 .96 660710 339290 338957 24 12 619662 4- 5g 938619 .96 661043 5-56 23 619938 4-59 958561 .96 661377 5-56 338623 22 3 9 620213 4-5o- 9385o3 •97 661710 5-55 . 3382O0 21 40 620488 4-58 958445 ■97 662043 5-55 337907 20 4i 9-620763 4-58 9-938387 ■97 9-662376 5-55 10-337624 10 42 62io38 4-57 938329 •07 662709 5-54 337291 336958 l8 43 62i3i3 4-57 958271I .97 663o42 5-54 n 44 621587 4-37 4-56 95821 3 -o7 6633 7 5 5-54 336625 16 '45 621861 958 1 54 ■97 663707 5-54 336293 i5 46 622i35 4-56 958096 •97 664039 5-53 335961 1 14 % 62^409 4-56 958o38 •97 664371 5-53 335629] l3 622682 4-55 937979 •97 664703 5-53 335297 12 P 6229561 4-35 623229 4 '-^ 957921 ■97 665o35 v 5-53 334965 11 5o 957863 •97 665366 5-52 334634 10 5i 9-6235o2 4-54 9-957804 •97 9 -6656 9 7 5-52 io-3343o3 2 52 623774 4-54 957746 .98 666029 5-52 333971 53 624047 4-54 937687 .98 66636o 5-5i 333640 I 54 624319 4-53 957628 ■98 66669I 5-5i 333309 55 624591 4-3J '957570 ■98 667021 5-5i ' 332979 . 332643 5 56 624863 4-33 95751 1 .98 667352 5-5i 4 tl 625i35 4-52 937452 .98 667682 5-5o 3323i8 3 625406 4-52 957393 957335 .98 66801.3 5-5o 331987 2 ■ 5, 625677 625948 4-52 .98 668343 5-5o 33 1657 1 6o 4-5i 957276 •98 668672 5-5o 33i328 Cosine Sine ea° Uotiuitf. D. ' .JP»fc_J M. SIN'ES V,*D TANGENTS. (25 DEGREES.' 43 It. Sine p. Cosine | D. Tan ff . D. Cotang. 9-625948 4 5l 0-957276 -98 9-668673 5-5o Io-33i327 60 I 626219 4 5l 937217 957158, .98 669002 5 49 330998 n a 626490 4 5i .98 669332 5 49 33o668 3 626760 4 5o 957099 .98 669661 5 49 33o33 9 p 4 627030 4 5o 957040 .98 669991 670320 5 48 330009 56 5 627300 4 5o 936981 • 98 5 48 329680 55 • 6 627570 4 49 936921 9 56862 •99 670649 5 48 329351 54 8 627840 628109 4 49 •99 670977 671306 5 48 329023 53 4 49 9 568o3 •99 5 47 328694 52 9 628378 4 48 956744 956684 ■99 671634 5 47 328366 5i 10 628647 9-628916 4 48 ■99 671963 5 47 328037 5o ii 4 47 n-956625 ■99 9-672291 5 4 I ,0-327709 49 12 629185 4 47 9 56566 ■99 672619 5 46 327381 48 i3 629453 4 a. 9565o6 •99 672947 5 46 32io53 326726 326398 47 14 629721 4 956447 ■99 673274 5 46 46 i5 629989 4 46' 936387 ■99 673602 5 46 45 16 630237 4 46 956327 936268 ■99 673929 5 45 326071 44 >7 63o524 4 46 ■99 674257 5 45 325743 43 18 630792 4 45 956208 •00 6 7 4584 5 45 3254i6 42 '9 63 1009 4 45 956148 •00 674910 5 44 325090 41 20 63i326 4 45 956089 •00 675237 5 44 324763 40 21 9-63i5q3 63i85 9 632125 4 44 g- 956029 •00 9.675564 5 44 ,o.324436 It 22 4 44 955969 •00 675890 5 44 324110 23 4 44 955909 955849 •00 676216 5 43 323784 37 24 6323o2 632658 4 43 •00 676543 5 43 323457 36" 25 4 43 955789 -00 676869 5 43 323i3i 322806 35 26 632923 4 43 955-729 •00 677194 5 43 34 2 633189 4 42 955669 •00 677520 5 42 322480 33 633454 4 42 955609 • 00 677846 678171 5 42 322)54 32 29 633719 4 42 955548. ■00 5 42 321829 3i 3o 633984 4 41 955488 •00 678496 5 42 32i5o4 3o 3i 9-634249 4 41 0-955428, ■01 9.678821 5 4i ,0-321179 29 32 6345 14 4 40 9 55368 ■01 679146 5 41 320854 28 33 634778 4 40 955307 1 ■01 679471 5 41 32o52q 320203 27 34 635o42 4 40 955247 •01 679795 6S0120 5 41 26 35 6353o6 4 3 9 955186 •01 5 40 319880 25 36 635570 4 3 9 955126 ■01 680444 5 40 .319536 24 ■ Ii 635834 4 3 9 955o65 • 01 680768 5 40 319232 23 '636097 4 38 o55oo5 ■ 01 681092 5 40 318908 3 1 8584 22 3 9 63636o 4 38 954944 ■01 681416 5 3 9 ,21 4o 636623 4 38 954883 • 01 681740 5 3 9 318260 20 41 9-636886 4 37 9-954823 • 01 q. 682o63 5 3 9 I0.3I7937 IO 42 637148 4 37 954762 • 01 682387 5 ll 317613 IS 43 637411 4 37 954701 ■ 01 682710 5 3n 2 9 17 44 63 7 6 7 3 4 37 954640 • 01 683o33 5 38 3 1 6967 16 45 637935 4 36 954579 •c: 683356 5 38 316644 i5 46 638197 638458 4 36 954518 • 02 683679 5 38 ,3i632i 14 47 4 36 954457 •02 684001 5 37 3 1 3999 i3 48 638720 4 35 934396 954335 ■02 684324 5 37 -3 1 2676 12 49 638981 4 35 ■02 684646 5 37 3i5354 11 5o 5i 639242 9 -639303 4 4 35 34 954274 9-954213 •02 ■02 684968 0-685290 5 5 37 36 3 1 5o32 lo-3i47i° 10 I 52 639764 4 34 954i52 •02 685612 5 36 3U388 53 640024 4 34 954090 ■02 685934 5 36 314066 54 640284 4 33 954029 953968 •02 686255 5 36 3 1 3745 55 640544 4 33 ■02 686577 5 35 3 1 3423 5 56 640804 4 33 953906 ■02 • 686898 5 35 3i3i02 4 .57 641064 4 32 953845 •02 687219 5 35 312781 3 58 64i324 4 32 953783 •02 687540 5 35 3 1 2460 2 5 9 64 1 584 4 32 933722 1 ■03 687861 5 34 3 1 2 1 39 3n8i8 1 60 641842 4-3i 953660 ■o3 688182 5-34 Cosine D. Sine 1 !4° Cotanfr. D. Tang. M. 44 (2G DEGREES.) A TABLE OF LOGARITHMIC M. a Sine D. Cosine D. i-o3 Tang. I). Cotruig. L- 9 -64 1842 4-3i 9-953660 9-688182 5-34 io-3ii8i8| 60 i 642101 4-3i 953599 i-o3 6885o2 5 ■34 311498 5g 2 642360 4-3i 953537 95347D i-o3 688823 5 34 311177 58 3 642618 4-3o i-o3 689143 5 •33 3 1 0857 57 4 642877 4-3o 9534i3 i-o3 68 9 463 5 ■33 3 1 o537 56 5 643i 35 4-3o 953352 i-o3 689783 5 •33 310217 55 6 643393 4-3o 953290 i-o3 690103 5 33 309897 54 I 643630 4-29 q53228 i-o3 690423 5 33 309577 309238 53 643908 4-29 933166 i-o3 690742 5 32 52 9 644i65 4-29 933104 i-o3 691062 5 32 3o8 9 38 5! 10 644423 4-28 933042 i-oj 6 9 i38i 5 32 308619 5o ii 9-6446* 4-28 9-952980 1-04 9-691700 5 3i io-3o83oo % 12 644936 4-28 952918 1-04 692019 5 3i 307981 l3 640193 4-27 952855 1-04 69233a 5 3i 307662 47 U 645430 4-27 932793 1-04 692656 5 3i 307344 46 i5 645706 4-2T 9 32 7 3 1 1-04 692975 5 3i 307025 45 16 645962 4-26 952669 1-04 693293 5 3o 306707 3o6388 44 \l 646218 4-26 952606 1-04 693612 5 3o 43 646474 4-26 952544 1 1-04 693930 5 3o 306070 42 19 646729 4-25 . 952481 1-04 694248 5 3o 3o5752 41 20 646984 4-20 952419' 1-04 694566 5 29 3o5434 40 21 9-647240 4-25 9-952356 1-04 9-694883 5 29 io-3o5ii7 11 22 647494 4-24 952294 1-04 695201 5 29 304799 3o44B2 23 647749 4-24 952231 1-04 6g55i8 5 29 37 24 648004 4-24 952168 i-o5 6 9 5836 5 29 304164 36 25 648258 4-24 932106 i-o5 696153 5 28 3o3847 35 26 648512 4- 23 952043 i-o5 696470 696787 5 28 3o353o 34 11 648766 4-23 951980 i-o5 5 28 3o32r3. 33 649020 4-23 951917 95 1 854 i-o5 697103 5 28 302807 32 9 649274 4-'22 i-o5 697420 5 27 3o258o 3,i 3o . 649527 4-22 951791 i-o5 697736 5 27 302264 3o 3i 9-649781 4-22 9.951728 i-o5 9-698053 5 2 7 10-301947 3 32 65oo34 4-22 961665 i-o5 6n836 9 .698685 5 27 3oi63i 33 630287 4-21 95 1 602 i.o5 5 26 3oi3i5 11 34 65o53 9 4-21 95i539 i-o5 699001 5 26 300999 35 650792 4-21 95 147.6 i-o5 699316 5 26 3oo684 25 36 65io44 4-20 * 951412 i-o5 699632 5 26 3oo368 24 32 631297 4-20 9 5i 349 1-06 699947 5 26 36oo53 23 65 1 549 4-20 , 9 5i286 1-06 700263 5 25 299737 22 3 9 65 1 800 4-19 951222 1-06 700578 5 25 299422 21 4o 652052 4-19 95i t5g 1-06 700893 5 25 299107 20 4i 9-6523o4 4-19 9-951096 1-06 9.701 2G8 5 24 10-298792 in 42 652555 4- 18 95io32 [■06 701 523 5 24 298477 10 43 652806 4- 18 950968 t.06 701837 5 24 298163 ■7 44 653o57 6533o8 •4- 18 95ooo5 [■06 702152 5 24 297848 16 45 4- 18 950841 1-06 702466 5 24 297534 i5 46 653558 4-17 950778 r-o6 702780 5 23 297220 14 47 6538o8 4-17 950714 1-06 703095 5 23 296905 296391 i3 48 654059 i\i 95o65o [■06 703409 '5 23 12 £ 9 6543oo 654558 95o586 ■06 703723 5 23 296277 11 . 5o 4-16 95o522 ■ 07 704036 5- 22 295964 10 5i 9-654808 4-16 9-950458 ■07 9-704350 5- 22 10-295650 8 52 655o58 4- 16 95o3o4 95o33o •07 704663 5 22 295337 53 655307 4-i5 ■07 704977 5- 22 293023 I 54 655556 4-i5 950266 ■07 705290 5- 22 294710 294397J 55 6558o5 4-i5 950202 •07 7o56o3 5- 21 5 56 656o54 4- U 95oi38| • 07 705916 5- 21 294084! 4 n 656302 4-14 950074' .07 706228 5- 21 293772' 3 65655i 4-i4 900010 • 07 706541 5- 21 293459' 2 5 9 656799 4-i3 949945, 949881 ! .07 706854 5- 21 293146! 1 6o 637047 4-i3 •07 707166 5- 20 292834I : Cosine D. Sine ' 83° Co tang. D. T^T|m7' SINES AND TANGENTS (27 DEGREES. ) 410 ii. Sine ; d. •Cosine | D. Tang. D. Cotang. ~6o~ 9-657047 657295 4-l3 ,-9-94988i : i-07 9-707166 5-20 10-292834 I 4-i3 949816'! -0" 707478 5-20 292522 5o 2 657542 4-12 949752 1 .07 707790 708102 5- 20 292210 58 3 657790 4-12 949688 i-o£ 5-20 291898 57 4 658o37 •4-12 949623.1 -ai 708414 5-19 291586 56 5 658a84 4-12 94g558ji-oe 708726 5-19 291274 55 6 69853i 4-u 94Q4Q4 1 -o£ 709037 5-19 290963 54 I 658778 4ii 949429'! -oi: 709349 5- 19 290651 53 659025 4-if 949364| I -ot 709660 5- 19 5-i8 290340 52 9 659271 4-10 9493oo 1-08 709971 290029 5i lo 65g5i7 4-io 949235 i-o8 710282 ' 5-i8 289718 5o II 9-659763 4-io 9-94917° 1-08 9-710593 5-i8 10-289407 i 12 66000c 660255 4-09 949105 1-08 7 1 0904 5-i8 2890 9 6 13 4-09 949040 1-08 71 [2l5 5-i8 288785 47 U 66o5oi 4-09 948975 i-o8 •7U525 5-17 288475 288164 46 15 660746 4-og 948910 948845 1-08 7II836 5-17 45 ■ 16 660991 4-o8 1 08 7 1 2 1 46 S"' 287804 a \l 6612J6 4-o8 948780 1-09 712456 5.17 287544 43 66148.1 4-o8 948715 1 -09 712766 5- 16 287234 42 '9 661726 4-07 94865o 1-09 713076 713386 5- 16 286924 41 20 661970 4- 07 948584 1 -09 5-i6 286614 40 21 9-662214 4-07 9-948519 1-09 9-713696 5.i6 10- 2863o4 n 22 66245o 662703 4-07 948454 1-09 714005 5- 16 285995 23 4-o6 948388 1-09 7i43i4 5-i5 285686 3? 24 662946 4-o6 948323 1 -09 , 7 '4624 5-i5 2853-76 285067 36 25 663190 663433 4-o6 948257 1-09 714933 5-15 ' 35 26 4-o5 948 1 g2 1-09 715242 5-i5 284758 34 2 663677 4o5 948126 i-og 7i555i 5-i4 284449 33 663926 4-o5 948060 i-og 7i586o 5-U 284140 32 ? 9 664163 4-o5 947995 l-IO 716168 5-i4 283832 3i 3o 664406 4-o4 947929 I-IO 716477 5-14 283523 3o 3i 9-664648 4-o4 9-947863 I -10 9-716785 5-U io-2832i5 3 32 664891 665i33 4-o4 * 947797 94773 1 I-IO 717093 5-i3 282907 282099 33 4-o3 I-IO 717401 5-i3 27 34 665375 4-o3 947665 I-IO 717709 718017 5-i3 282291 26 35 665617 4-o3 947600 i-iq 5-i3 281983 25 36 66585 9 4-02 947533 I-IO 7i8325 5-i3 281670 281367 24 ll 666100 4-02 947467 I-IO 7i8633 5-12 23 666342 4-02 9474oi I-IO 718940 5-12 ,281060 22 3 9 666583 4-02 947335 I-IO 719248 5-12 280752 21 4o 666824 4-oi 947269 9-947203 I-IO 719555 5-12 280445 20 41 9 • 667065 4oi I-IO 9-719862 5-12 io-28oi38 ;g 42 667305 4oi 947136 i-n 720169 5-ii 27983 1 43 667546 4-oi 947070 1 -M 720476 5-u 279524 17 44 667786 668027 4-oo -947004 i-n 720783 5-n 279217 27891 1 16 45 4-oo 946937 1 -ii 721089 5-n i5 it 668267 4-oo 94687 1 ] 1 ■ 1 1 721396 5-u 278604 14 % 6685o6 3-99 946804! 1. -ii 721702 5io 278298 .i3 668746' 3-99 946738! 1 • 1 1 722009 5io 277991 12 49 668986 3- 99 94667 1 ■ 1 ■ 1 1 722310 5-io 277685 11 5o 66g225 ( 3-99 9 • 669464 3 ■ g8 946604' i-ii 722621 5-io 277379 10-277073 10 5i" 9 946538 i-n 9-722927 5-io I 52 669703; 3-98 94647 1 1 • 1 1 723232 5-09 276768 53 669942' 3 -98 946404 1 -ii 723538 5-09 276462 7 54 670181! 3-g7 946337 i-n 723844 5-09 276156 6 55 670419' 3-g7 946270.1 -12 724149 5 -09 275851 5 ' 56 670658 3-97 946203.I-I2 724454 5-oo 275546 4 Si 670896 671 1J4 3-97 946l36 1-12 724759 5-o8 275241 3 3 -96 946o69Ji-i2 725o65 5-o8 274935 2 5q 671372 3-g6 946002! 1 ■ 12 720369 5-o8 27463i 1 oo 1 671609 Cosine | 3-96 94593 5 1 I-'!2 6201 720674 Cotang. 5-o8 274326! r 1 D. Sine ! D. Tang. J M._ 46 (28 DEGItEES.) A TABLE OP LOGARITHMIC M. Sine D. Cosine | D. Tang. | D. Cotang. > 60 9-67160$ 3.96 o.-945§35'i.n 945868 1 - 1 - 9-725674! 5- 08 10-27432* i 67184- 3. 9 5 725979' 5-o8 27402 59 3 67208/ 3. 9 5 94.5800 1 • 1 - 726284 1 5-07 273716 58 3 672321 3. 9 5 945733 1 - 1 1 726588, 5-07 27341 ' 5 7 56 4 67255E 3.95 945666 1 - 1 ; 726892; 5-07 27310! 5 672795 673032 3.94 945598 1 • 1 1 9455J1 1 - IS 7271971 5-07 27280C 55 6 3.94 727501 5-07 272499 54 I 673268 3.94 945464 1 ■ 1 ; 727805 5-o6 272190! 53 673500 3.94 945396 i-i; 728109 5-o6 271891I 52 9 673741 3.93 945328 i-i; 728412 5-o6 271588 ! 3| 10 673977 3. 9 3 945261 I-K 728716. 5-o6 271284 5o ii 9-67421; 3- 9 3 9-945I93 I-K g. 729020 5-o6 10-270980 49 48 12 674448 3-92 9 1012:3 1 -K 729323 5-o5 27067- 13 6746S4 3-92 945o58 i-k 729626 5-o5 27037/ 47 14 674919 3-92 944990 i-i; 729929' 5-o5 73o233 5-o5 270071 46 i5 670100 3-92 944922>i-l3 26976- 45 16 675390 3-91 944854 i-i 3 73o53! 5-o5 26946! 44 \l 675624 3-91 944786 i-i3 73o83f ) 5-o4 269162 43 6 7 585 9 3-91 944718 1 - 13 73 1 141 5-04 268859 41 '9 676094 3-91 94465o 1 . 1 3 7314& i 5-04/ 268556 41 20 676328 3-qo 944582 i- 1 4 73i74< 5-04 268254 4o 21 9-676562 3 90 9-9445i4 1-14 9.73204E 5-o4 10-267952 ll 52 676796 677030 3.90 944446 1 -14 73235i 5-o3 267649 23 3- 9 o 944377 1-14 732653 5-o3 267347 37 24 677264 lb 944309 1-14 732955| 5-o3 267045 36 25 677498 67 7731 ■H' 944241.1-14 733257! 5-o3 733558, 5-o3 266743 35 26 3-8 9 9441721-14 266442 34 IS 677964 , 3-8§ 944104 1-14 733860 5-02 266140 33 ' 678197 3-88 944o36 1 • 14 734l62| 5-02 265838 32 -?° 6-i843o 3-88 943967^.14 734463| 5-02 26553 7 3i 3o 673663 3-88 9438991-14 9-943830,1-14 734764 5-02 265236 3o 3i 9-678895 Ml 7 9-735o66i 5-02 10-264934 29 32 679128 3-87 943761,1-14 735367 5-02 735668: 5-oi 264633 28 33 679360 3-8 7 943693 1 - 1 5 264332 27 34 679592 3.87 943624 1 -i5 735969! 5-oi 26403 1 26 t 35 ■ 679824 68oo56 680288 3-86 913555 1 . i5 736269 5-oi 263731 25 l 16 u 3-86 3-86 943486.1 -iS 943417 1 - 15 943348i-i5 736570 73687 1 5-oi 5-oi 263430 263 1 29 24 23 680019 3-85 -737171 5-oo 262829 22 3 9 680750 3-85 943279 i-i 5 737471 5-oo 262529 21 40 680982 3-85 943210 1 -iS 737771 5-oo 262229 20 41 9-68i2i3 3-85 9-943U1 1 - 1 5 9-738071 5-oo 10-261929 in 42 681443 3-84 943072 i-i5 738371 5-oo 261629 IB 43 681674 3-84 943oo3 i-i5 738671 4.99 261329 >7 44 681905 384 942934 1 - 1 5 738971 4-99 261029 16 45 682135 3-84 942864 i-i 5 739271 4.99 260729 i5 46 682365 3-83 942795 1-16 739570 4-99 260430 14 % 682595 3-83 942726 i- 16 739870 4-99 260 i3o i3 682823 3-83 942656 1-16 740169 1 4-99 2598.31 12 i 9 683o55 3-83 942587, 1 • 16 740468 4.98 209532 11 5o 683284 3-82 9425ij'i . 16 9-942448 I- 16 740767 4.98 s5o233 10 5i 9-6835U 3-82 9-741066 4-98 10-258934 I 52 683743 3-82 942378 i- 16 74-a65 4-98 208635 53 683972 3-82 9423o8 I- 16 741664 4-98 258336 I 54 684201 3-8i 942239^1 • 16 741962 4-97 258o38 55 68443o 3-8i 94216911-16 742261 4-97 257739 5 56 684658 3-8i 942099 1 . 16 742559 4-97 257441 4 U 684887 ' 3-8o 942029 1 -16 742858 4-97 •257142: 3 685n5' 3-8o 941959 I- 16 9418891-17 743 1 56 4-97 256844 2 I 9 685343 3-8o 743454 4-97 4-96 D. " 256546| 1 6o 685571 3-8o 941819 1-17 743752 Cotang. 256248] Cosine D. Sine 61° Tang. 1" M. SINKS AND TANGENTS. (29 DEGREES. 1 il M. Sine I). Cosine | D. Tang. D. Cotang. 9-685571 3-8o 9-941819 1-17 9-743752 4-96 10 -256248 60 1 I 685799 3-79 94H49 I- 17 744o5o 4.96 255950 5 9 I 68602^ 3-79 941679 1 -17 744348 4-96 255652 58, 3 686254 3-79 ' 941609 1. 17 744645 4-96 255355 n 4 686482 3-79 94i53g i- 17 744943 4.96 255657 5 686709 3- 7 § 941469 1 -17 745240 4.96 254760 55 6 686g36 3-78 941398 1 -17 ' 745538 4-95 254462 54 I 687163 3- 7 8 94i328 1 - 17 745835 4-95 254i65, 53 687389 3-78 941258,1-17 746i32 4-95 253868 52 9 687616 3-77 ' 941187J1-17 746429 4-95 253571 ■?' ' 10 687843 3.77 941117,1-17 746726 4-95 253274 5o , II 9-688069 688295 3-77 9-94104611 -iE 9-747023 4.94 10-252977 252681 t 12 \]l 940975 I- 1£ 747319 4.94 i3 688521 g4ooo5|i-iE 747616 4-94 252384 47 14 688747 3-76 940834! i- 18 747913 4-94 252087 46 15 688972 3-76 940763 I- 1£ 748209 4-94 251791 45 16 689198 3- 7 6 940693 I- 18 7485o5 4-93 25i495 44 \l 689423 3- 7 5 940622 I- iS 748801 4-93 251199 250903 43 689648 |-75 94o55 1 i- 16 749097 4- 9 3 42 '9 68987; 3-75 940480 i- 18 7493t)3 4-93 250607 41 20 690C9J 3-75 940409 I- 18 749689 9-749985 4- 9 3 25o3n 40 21 9^69032.' /3-74 9 .940338 i-iB 4-93 io-25ooi5 It 22 690548 3-74 940267 1-18 750281 4-9 2 - 249719 23 690772 3-74- 940196 i- 18 750576 4-92 249424 37 24 690996 3-74 940125:1-19 750872 4-92 249128 36 23 691220 3-73 94oo54|i-i9 761167 4-92 248833 35 26 691444 3- 7 3 939982 1 • 19 751462 4-92 248538 34 27 691668 3- 7 3 9 3 9 9i 1 1-19 751757 4-92 248243 33 28 691892 3- 7 3 939840 1-19 752052 4-91 247948 32 29 6921 i5 3-72 939768 1-19 752347 4-91 247653 3i 3o 692339 3-72 939697 1-19 ;52642 4-91 247358 3o' 3i 9-69256: 3-72 9-939625 1-19 9-752937 4-91 io-247o63 2Sl 32 69278s 3-71 939554 1 -19 75323i 491 246769 33 6g3oof 3.71 939482 1-19 753526 4-91 . 2464741 27 34 6g3 23 1 3- 7 i 939410 1-19 753820 4-9° 246180 26 35 693453 3-71 939339 1-19 7541 i5 4.90 245885 25 36 693676 3, -70 9J9267 1-20 754409 754703 4.90 245591 24 3 7 693898 3-70 939195 1-20 4-9° 245297 23 38 694120 3-70 939123 1-20 75*997 4.90 245oo3 22 3 9 694342 3-70 939052 938980 1-20 755291 7 55585 4.90 4-89 244709 21 40 694564 3-6 9 1-20 244413 20 41 9 • 694786 3-6 9 9.938908 1-20 9-755878 4.89 10-244122 !8 .42 695007 3-6 9 ■ 9 38836 1-20 756172 756465 4-8 9 243828 43 695229 3-6 9 ■ 938763 1-20 4-89 243535 n 44 695450 3-68 938691 1-20 756759 4-89 243241 16 45 69567 1 3-68 938619 1-20 757052 4-8o 242948 i5 46 695892 3-68 938547 1-20 757345 4-88 242655 14 % 6961 1 3 3-68 938475 1-20 757638 4-88 242362 i3 696334 3-6 7 938402 I-2I 757931 4-88 242069 12 49 696554 3-67 9 3833o I • 21 758224 4-88 241776 11 5o 696775 3-67 ■ 938238 I-2I 7585i7 4-88 24U83 10 5i 9-696995 3-67 9- 9 38i85 1-21 9-758810 4-88 10-241190 6 52 697215 3-66 938n3 1 -21 759102 4-87 240898 53 697435 3-66 938040 1 .21 759395 4-87 24o6o5 7 54 697654 3-66 937967 I -21 759687 4.87 24o3i3 6 55 697874 3 =-66 937895 I -21 759979 4^-87 240021 5 56 698094 3-65 937822 I - 21 760272 4-87 239728 4 5 7 6 9 83 1 3 3-65 937749 1-21 760564 4-87 239436 3 58 698532 3-65 937670 I - 21 76o856 4-86 239144 238852 2 5 9 698751 3-65 937604 I-2I 761 148 4-86 ' I 66 698970 3-6,4 937531 I -21 761439 4-86 238561 Cosine D. Sine 80° Co tang. D. Tang^ J*> 24 (8 (30 DEGREES.) A TABLE OF LOGARITHMIC M. Sine D. Cosine | D. Tang. D. Cotang. 9.698970 3-64 9-937531 1 .21 9-761439 4-86 10. 23856i 60 i 699189 3 64 937458 1-22 761731 4 86 " 238269 S8 57 3 3 699407 699626 3 3 64 64 937385, 987312' ■22 1-22 762023 762314 4 4 86 86 =37977 237686 4 699844 3 63 937238! 937165' 1-22 762606 4 85 237394 56 5 700062 3 63 1-22 762897 . 7 63 1 88 4 85 237io3 55 6 700280 3 63 937092J '22 4 85 236812 54 I 700498 3 63 9370191 •22 7634T9 4 85 236521 53 700716 3 63 936946 •22 763770 4 85 23623o 52 9 700933 3 62 936872! •22 764061 4 85 235939 235648 5i 10 70ii5i 3 62 936799 9-936725 ■22 764352 4 84 5o ii 9-701868 3 62 ■22 9 ■764643 4 84 10-235357 **2 12 701585 3 62 936652 •23 764933 4 84 2J5067 48 i3 701802 702019 3 3 61 61 936578 9365o5 ■23 •23 765224 7655i4 4 4 84 84 234776 234486 % 15 702236 3 61 93643i •23 7658o5 4 84 234195 45 16 702452 3 61 936357 •23 766095 766385 4 84 233905 44 \l 702669 702885 3 60 936284 ■23 4 83 2336 1 5 43 3 60 936210 •23 766675 4 83 233325 42 "9 7o3ioi 3 60 936 1 36 ■23 766965 4 83 233o35 41 20 703317 3 60 936062 •23 767255 4 83 232745 40 21 9-703 533 3 5 9 9-935988 •23 9-767545 4 83 10-232455 \l 22 703749 3 5 9 935914 935840 ■23 767834 768124 4 83 232166 23 703964 3 5 9 ■23 4 82 231876 37 24 704179 ' 704395 3 5 9 935766 ■24 768413 4 82 23 1 587 36 25 3 5 9 935692 •24 768703 4 82 231297 35 26 704610 3 58 9356i8 • 24 768992 4 82 23 1008 34 3 704825 3 58 935543 ■24 769201 4 82 230719 33 705040 3 58 935469 ■ 24 769570 4 82 23o43o 32 n 9 705254 3 58 935390 ■24 769860 4. 81 23oi4o 3i 3o 705469 9 •.7o5683 3 57 935320 •24 770148 4 81 229852 3o 3i 3 57 9-935246 •24 9.770437 4 81 10-229563 29- 32 705898 3 5 7 935171 • 24 770726 4 81 229274 228985 228697 28 33 7061 12 3 57 935097 ■24 771015 4 81 11 34 706326 3 56 935022 ■24 77i3o3 4 81 35 706539 706753 3 56 934948 • 24 771592 771880 4 81 228408 25 36 3 56 934873 ■ 24 4 80 228120 24 u 706967 3 56 934798 ■25 772168 4 80 227832 23 707180 3 55 934723 ■25 772457 4 80 . 227543 22 39 707393 3 55 934649 •25 772745 4 80 227265 21 40 707606 3 55 934574 •25 773o33 4 80 226967 20 41 9-707819 3 55 9-934499 •25 9-773321 4 80 10.226679 !3 42 708032 3 54 934424 •25 7 7 36o8 4 79 226392 43 708245 3 54 934349 •25 7738o6 4 79 226104 \l 44 708458 3 54 934274 •25 774184 4 79 2258i6 45 708670 708882 3 54 934199 934123 •25 774471 4 79 225529 i5 46 3 53 ■25 774759 4 79 225241 14 % 709094 3 53 934048 •25 775046 4 79 224954 i3 709306 3 53 933973 •25 775333 4 7? 224667 12 49 709518 3 53 933898 • 26 775621 4 78 224379 11 5o 709730 3 53 933822 • 26 775908 4 78 224092 10 5i 9-709941 3 52 9-933747, • 26 9-776195 4 78 io-2238o5 I 52 7ioi53 3 52 933671 • 26 776482 4 78 2235i8 53 710364 3 52 9 335 9 6 ■ 26 776769 777055 4 78 22323l 7 54 710575 3 52 93352o! ■ 26 4 78 222945 6 . 55 710786 3 5i 933445 • 26 777342 4 .78 222658 5 56 710997 711208 3 5i 933369! 933293] • 26 777628 4 77 22^372 4 u 3 5i ■ 26 777915 4 77 222085 3 711419 3 5i 933217 ■ 26 778201 4 77 221799 2 5 9 711629 3 5o 933i4i ■ 26 778487 4 77 22l5l2J I 60 71 1839 3-5o 933066] • 26 778774 4-77 221226] Cosine D. Sine 1 5a° Cotang. D. Tang. I M. StNTES AND TANGENTS. (31 DEGREES. ) 49 a. o Sine 9-7ii83^ D. Cosine 1 D. Tang. D. Cotang. 3 5o 9.933066 1-26 9-778774 4 77 10-221226 60 ' I 712060 3 5o 932990 1-27 779060 4 76- 220940 220654 59 2 712263 3 5o 932914 ■ 27 779346 4 58 3 712469 3 49 932838, • 27 779632 4 t 220368 l r 4 712679 3 49 932762 ■27 779918 4 7& 220082 56 5 712889 713098 3 49 932685 1-27 780203 4 t 219797 55 6 3 49 932609 932533 [-27 780489 780776 4 76 21931 1 54 J 7i33o8 3 49- 1-27 4 76 219225 2 1 8940 53 713517 3 48 932457 1-27 781060 4 76 52- 9 713726 3 48 93238o 1.27 781346 4 ~>\ 218654 5i 10 713935 3 48 932304 1-27 78i63i 4 75 218369 5o ii 9-714144 3 48 9-932228 1-27 9-781916 4 7 5 10-218084 49 12 714352 3 47 g32l5i •27 782201 4 75 2 '7799 48 i3 1456 1 3 47 932075 •28 782486 4 75 217514 47 !4 714769 3 47 931998 •28 782771 4 75 217229 46 i5 714978 3 47 931921 93i845 •28 783o56 4 75 2 i 6944 45 16 7i5i86 3 47 • 28 783341 4 7 5 216659 44 17 7 1 53 9 4 3 46- 931768 -28 783626 4 74 216374 43 1 8 715602 3 46 931691 ■28 783910 4 74 216090 42 '9 7 1 5809 3 46 931614 ■28 784195 4 74 2i58o5 41 20 716017 3 46 9^1537, 1-28 784479 4 74 2 1 552 1 40 21 9-716224 3 45 9.931460! ■ 28 9-784764 4 74 io-2i5236 3o 22 716432 3 45 9 3 1 383 .28 785048 4 74 214952 38 23 716639 3 45 93i3o6 •28 785332 4 73 214668 37 '24 716846 3 45 931229 ■29 7 856i6 4 73 214384 36 25 717053 3 45 93 1 1 52 ■ 29 785900 4 73 214100 35 20 717259 3 44 931075 •29 786184 4 73 2i38i6 34 .27 717466 3 44 930998 •29 786468 4 73 2 1 3532 33 28 717673 3 44 930921 93o843 ■ 29 786752 4 73 2i3248 32 29 717879 718085 3 44. ■29 787036 4 73 2 1 2964 3i 3o 3 43 930766 • 29 787319 4 72 212681 3o 3i 9-718291 3 43 9,930688 •29 9-787603 4 72 10-212397 u 32 718497 3 43 93o6i 1 •29 787886 4 72 212114 33 718703 3 43 93o533i •29 788170 4 72 2ii83o 27 34 718909 3 43 93o456 .29 788453 4 72 2 1 1 547 26 35 719114 3 42 93o378 •29 788736 4 72 2 1 1 264 25 36 719320 3 42 93o3oo -3o 789019 4 72 2 1 O98 1 24 n 719525 3 42 93o223 -3o 789302 4 7' 2 [ 0698 23 719730 3 42 93oi45 •3o 789585 4 71 2I04l5 22 3 9 719935 3 41 930067 -3o 789868 4 71 2IOI32 21 4o 720140 3 41 - 929989 • 3o 790i5i 4 71 209849 20 &\ 9-720345 3 41 9.92991 1 929833 ■ 3o 9-790433 4 71 10-209567 19 4? 720549 3 41 -3o 790716 4 71 ■ 209284 18 43 720754 3 40 929755 -3o - 790999 4 7f 20O0O1 17 44 720958 3 40 929677 -3o 791281 4 71 208719 -16- 45 721162 3 4o 929599 -3o 79 1 563 4 70 208437 i5 46 72 1 366 3 40 929521 -3o 791846 4 70 2o8i54 14 47 721570 3 40 929442 -3o 792128 4 70 207872 i3 48 721774 3 3 9 929364 • 3i 792410 4 70 207590 12 49 721978 3 3g 929286 • 3i 792692 4 70 207308 11 56 722181 3 3 9 929207 • 3i 792974 4 70 207026 10 5i 9-722385 3 3 9 9-929129 •3i 9 ' 7 '^^ 4 70 10-206744 9 52 722588 722791 3 3o 92oo5o ■3i 793538 4 69 206462 8 53 3 38 928972 • 3i 793819 4 69 206181 I 54 722994 3 38 928893 • 3i 794101 4 69 205899 55 723197 3 38 928816 • 3i 794383 4 69 205617 5 56 723400 3 38 928736 • 3i 794664 4 69 205336 4 57 7236o3 3 37 928657 • 3i 794945 4 2 9 2o5o55 3 58 7238o5 3 37 928578 928499 ■ 3i 795227 4 69 204773 1 59 724007 3 37 ■3i 795508 4 68 204492 1 60 724210 3 37 . 928420 •3i 795789 4 68 2042 m Cosine D- Sine 58° Cotang. D. Tang. M. | 50 (32 DEGREES.) A TABLE OF LOGARITHMIC It. Sine D. Cosine | D. Tang. D. Cotang. 9-724210 3-37 9-928420' • 32 9.795789 4 68 10-204211 60 I 724412 3 ll 36 928342 ■32 796070 4 68 203930 2 3 724614 724816 3 3 9 28263 ; 928183 •32 •32 796351 796632 4 4 68 68 203649 203368 4 725017 3 36 928104 •32 796913 4 68 2o3o8t 202806 5 723219 3 36 928025 •32 797194 4 68 55 6 725420 3 35 927946 •32 797475 797 7 55 4 68 202525 54 I 725622 3 35 927867 •32 4 68 202245 53 •725823 3 35 927781 •32 7g8g36 4 67 201964 02 9 10 726024 3 35 927708 927629 •32 798316 4 67 201684 5i 726225 3 35 •32 798596 4 67 201404 5o 11 9.726426 3 34 9-927549 •32 9.798877 4 67 10-201123 % 12 726626 3 34 927470 ■ 33 799157 4 67 200843 i3 726827 3 34 927390 •33 799437 4 67 200563 % 14 727027 727228 3 34 927310 • 33 799717 4 67 200283 15 3 34 927231 • 33 799997 800277 4 66 200003 45 16 727428 3 33 927151 ■33 4 66 199723 44 \l 727628 3 33 927071 ■ 33 8oo557 4 66 199443 43 727828 728027 3 33 926991 • 33 ,8oo836 4 66 199164 • 198884 42 19 3 33 92691 1 ■ 33 801 116 4 66 41 20 728227 3 33 926831 ■ 33 801396 4 66 198604 40 21 9-728427 3 3a 9-926751 926671 .33 9-801675 4 66 10-198335 38 22 728626 3 32 ■ 33 - 8oi 9 55 4 66 198045 23 728825 3 32 926591 1-33 802234 4 65 197766 IT 24 729024 3 32 9265i 1 1-34 8o25i3 4 65 197487 25 729223 3 3i 926431 1-34 802792 4 65 197208 35 26 729422 3 3.1 92635i [-34 803072 4 65 196928 34 ll 729621 3 3i 926270 1-34 8o335i 4 65 196649 33 729820 3 3i 926190 1-34 8o363o 4 65 196370 32 20 730018 3 3o 926110 1-34 803908 4 65 196092 3i 3o 730216 3 3o / 926029 [■34 804187 9-804466 4 65 195813 3o 3i 9-73o4i5 3 3o 9-925949 925868 [-34 4 64 10.195534 •3 32 73061 3 3 3o r-34 8o4745 4 64 195255 33 73o8i 1 3 3o 925788 [-34 8o5o23 4 64 194077 194698 27 34 731009 731206 3 29 925707 [■34 8o53o2 4 64 26 35 3 29 925626 1-34 8o558o 4 64 194420 25 36 73i4o4 3 29 925545 1-35 8o585 9 4 64 194141 24 ll 731662 3 29 925465 1-35 806137 4 64 193853 23 731799 3 29 925384 1-35 80641 5 4 63 193585 22 3 9 731996 3 28 9253o3 [-35 806693 4 63 193307 21 4o 732193 3 28 925222 1-35 806971 4 63 193029 20 41 9-732390 732587 3 28 9-925141 [■35 9-807249 4 63 10-192751 II 42 3 28 925o6o 1-35 807527 807805 4 63 192473 43 732784 3 28 924979 924897 [•35 4 63 192195 \l 44 732980 3 27 [-35 8o8o83 4 63 191917 45 733177 3 27 924816 i-35 8o836i 4 63 191639 i5 46 7 333 7 3 3 27 924735 [-36 8o8638 4 62 191362 14 % 733569 733765 3 27 924654 i-36 808916 4 62 191084 i3 3 27 924572 [-36 809193 4 62 190807 12 £ 733961 3 26 924491 1-36 809471 4 62 190529 11 734r57 3 26 924409 1-36 809748 4 62 IO0252 10-189975 10 h 9-734353 3 26 9-924328 [-36 9-810025 4 62 I §2 734549 3 ?6 924246 [-36 8io3o2 4 62 189698 5-3 734744 3 25 924164 [-36 8io58o 4 62 189420 I 54 73493 2 3 25 924083 [-36 810857 -4 62 189143 188866 55 735i3d 3 25 924001 [.36 811 i34 4 61 5 56 73533o 3 25 923919 1-36 811410 4 61 188590 4 8 735525 3 •25 923837 1 [-36 81 1687 4 61 i883i3 3 735719 3 •24 923755| .-3 7 811964 4 61 i88o36 1 5o 735914 3 •24 923673 1.37 812241 4 61 187759 i $P 736iog 3 •24 923591 [•3 7 812517 4-61 18748J Cpiino D, Sine |5T° Cotang, r>. Tan K . ST fc ■r-r- SINES A ND V TAH'GENTS. (33 DEGREES.) 51 M. Sine | D. Cosine D. | Tang. D. Cotang. 9-736109 3-24 9-923591 i-3 7 9-812517 4-6i 10-187482 60 I 7363o3 3-24 923509 1 -3 7 812794 4-6i 187206 is 3 736498 3-24 923427 i-3 7 813070 4-6i 186930 186653 3 736692 3-23 ■ 923345 i-3 7 8i3347 4.60 57 4 736886 3-23 923263 i-3 7 8i3623 4.60 186377 56 5 6 737080 737274 ,3-23 3-23 923181 923098 ,.3 7 1.37 813899 814170 4.60 4.60 186101 185825 55 54 I 737467 3-23 923016 i-37 8i4452 4.60 185548 53 737661 3-22 922933 922851 !-3 7 814728 4-6o 185272 52 9 10 737855 3-22 i-3 7 8i5oo4 4.60 184906 5i 738048 3-22 922768 i-38 815279 9-8i5555 4-6o •184721 5o ii 9-738241 3-22 9-922686 i-38 4-59 io-i84445 49- 12 738434 -3-22 922603 i-38 8i583i 4-5 9 184169 i838 9 3 48 i3 738627 8-21 922520 1-38 816107 4- 5 9 47 14 738820 3-21 922438 1-38 8:1 6382 4, 5 9 i836i8 46 i5 739013 3-2! 922355 1-38 8i6658 4.59 183342 45 16 739206 3-21 922272 922189 1-38 . 816933 4-5 9 183067 44 \l 739398 3-21 1-38 817209 4-59 182791 43 736590 3-20 922106. 1-38 817484 4-59 182516 42 <9 20 739783 3-20 922023 1-38 817759 8i8o35 4-5o 182241 -41' 739975 3-20 921940 9-921857 1-38 4-58 181965 40 31 9-740I67 3-20 i-3 9 g-8i83io 4-58 10-181690 18 22 740359 3-20 921774 1-39 8 1 8585 4-58 181415 23 74o55o. 3-19 921691 1 -3q ■ Si 8860 4-58 181 140 37 24 740742 3-19 921607 1.39 819135 4-58 i8o865 36 35 25 740934 3-19 921524 i-3 9 819410 4-58 180590 26 741 1 25 3-io 921441 i-3o 819684 '4-58 i8o3i6 34 27 74i3i6 3-io 921357 1-39 819969 4-58, 1 8004 1 33 28 741 5o8 3-i8 921274 i-3 9 820234 4-58 179766 32 29 741699 3-i8 921 190 1-39 82o5o8 4-67 179492 3i | 3o 741889 3-i8 921107 1 -3g 820783 4-57 179217 10-178943 3o 3i 9-742080 742271 742462 3-i8 9-921023 1-39 9-821057 4-57 20 \ 32 3-i8 920939 920856 i-4o 82i332 4-57 178668 28 33 3-17 i-4o 821606 4-5 7 178394 11 34 35 742652 742842 3-i 7 3-i 7 920772 920688 i-4o 1-40 821880 822154 4-57 4- 5 7 178120 177846 26 25 36 743o33 3-i 7 920604 i-4o 822429 822700 4-57 177571 24 23 -37 743223 3-i 7 920520 i-4o 4.57 177297 38 7434i3 3-i6 920436 i-4o 822977 4-56 177023 176760 22 3 9 40 7436o2 743792 3-i6 920352 i-4o 823250 4-56 21 3-i6 „ 92026^ i-4o 823524 4-56 176476 20 41 9.743982 " 3-i6 9-920184 i-4o 9-823798 4-56 10-176202 178928 175655 '7 42 43 44 45 46 7,44i7i 74436i 744550 744739 744928 74 5l V7 7453o6 74549* 3-i6 3-i5 92009c 92001' i-4o i-4o 824072 824345 4-56 4-56 3-i5 3- 15 3-i5 9i993i!i -41 919846;! -41 9197621-41 824619 | 824893 825i66 4-56 4-56 4-56 175381 175107 i 7 4834 16 i5 14 il 3- 1 5 3-i4 919677 1 -41 919593 r -4^ 82543a 82571; 4-55 4-55 1 74661 174287 i3 12 it 3-i4 919508 1 -41 825986 4-55 1 740 1 4 11 745683 3-14 9i9424|i-4i 826255 4-55 173741 10 5i 52 9-745871 746o5c 3-14 3-U 9-9193391 -4i 91925411 -41 9-826532 82680E 4-55 4-55 io- 17346E 173195 I 53 746248 746436 746624 7468 r 2 -746999 747187 747374 7475M 3-i3 9I9i6q!i-4i 827076 4-55 172922 I 5 54 55 4-i3 3-i3 91908* 9 1 900c i-4> 1-41 827351 827624 4-55 4-55 17264c 172376 56 57 58 iS 60 3i3 3-i3 91891! 9 1 883c 1-43 1-45 82789- 82817c 4-54 4-54 172 1 o3 17183c 3 3-12 3-ia 3-12 91874' 9 1 865c I 91857* I-4S I -45 J-i-41 82844! 82871; 82898- 4-54 4-54 4-54 I7I55S 171285 17101; 2 I ° Cosine D. I Sine |58< Cotang. D Tang. 1 M.. 24* 52 (^ DEGREES ) A TABLE OF LOGARITHMIC M. . Sine D. Cosmo j D. Tang. D. Cotnng. 9-747562 3-12 9-918574! 918489' t-42 9-828987 4 54 10-171013 60 1 747749 3 12 1-42 829260 4 54 170740 38 a 747936 748123 3 12 918404, 1-42 829532 4 54 170468 3 3 n 9 i83i8 1-42 829805 4 54 170195 57 4 7483io 3 n 918233 1-42 830077 4 54 169923 56 5 748497 748683 3 11 918147 1-42 83o349 4 53 1 6965 1 55 6 3 11 918062 1-42 83o62i 4 53 169379 54 o 748870 3 n 917976 1-43 83o8 9 3 83n65 4 53 169107 53 749056 3 10 917891 [-43 4 53 168835 5] 9 749243 3 10 917805 •43 83U37 4 53 ■68563 5i 10 749429 9-749615 3 10 917719 •43 831709 4 53 168291 5o n 3 10 9-917634 •43 9.831981 4 53 10-168019 4o 12 749801 3 10 917548 •43 832253 4 53 '67747 i3 749987 3 09 917462 -43 832525 4 53 167475 47 14 750172 3 09 917376 1-43 832796 4 53 167204 46 15 16 75o358 75o543 3 3 09 09 917290 917204 [-43 ■43 833o68 833339 4 4 52 02 166932 166661 45 44 \l 750729 3 3 917118 •44 8336n 4 52 i6638 9 166118 43 750914 3 917032 1-44 833882 4 52 42 19 751099 3 08 916946 •44 834i 54 4 52 J65846 41 20 751284 3 08 916859 •44 834425 4 52 165575 40 21 9-751469 3 08 9-9r6773 916687 •44 9-834696 4 52 io-l653o4 38 22 75 1 654 3 08 ■44 834967 835238 4 52 l65o33 23 75i83o 752023 3 08 916600 -44 4 52 164762 37 24 3 07 9i65i4 •44 8355og 4 52 1 6449 1 36 25 752208 3 07 916427 •44 83578o 4 5i 164220 35 26 ■7523g2 3 07 916341 •44 836o5i 4 5i 163949 34 11 752376 3 °7 916254 •44 836322 4 5i 163678 33 752760 3 07 916167 ■45 8365 9 3 4 5i 163407 32 29 752944 3 06 916081 •45 836864 4 5i i63i36 3i 3o 753128 3 06 915994 ■45 837134 4 5i 162866 3o 3i 9-7533i2 3 06 9-915907 •45 9-8374o5 .4 5i 10-162595 28 32 753495 3 06 915820 ■45 837675 4 5i 162325 33 753679 3 06 915733 •45 83 79 46 4 5i 162054 27 34 753862 3 05 915646 •45 838216 4 5i 161784 26 35 754046 3 o5. 915559 ■45 838487 4 5o I6i5i3 25 36 754229 3 o5 015472 ■45 838 7 5 7 4 5o i6i,243 24 u 754412 3 o5 9 i5385 •45 839027 4 5o 1 60973 23 754595 3 o5 915297 •45 83 9 2 97 4 5o 160703 22 39 754778 3 04 915210 ■45 83 9 568 4 5o 160432 21 .40 754960 3 04 9i5i23 •46 83g838 4 5o 160162 20 41 9-755i43 3 04 9"9i5o35 •46 9-840108 4 5o 10-159892 ;g 41 755326 3 04 914948 914860 ■46 840378 4 5o 159622 43 7555o8 3 04 ■ 46 846647 4 5o i5 9 353 lo 44 755690 3 04 9U773 ■ 46 840917 4 49 i5 9 o83 45 75587S 3 o3 9U685 ■46 841 187 4 49 i588i3 i5 46 756o54 3 o3 914598 ■46 841457 841726 4 49 158543 14 % 756236 3 o3 9U5io ■46 4 49 158274 i3. 756418 3 o3 914422 ■46 841996 4 -49 1 58oo4 12 i 9 756600 3 o3 9U334I 914246! •46 842266 4 49 157734 11 5o 756782 3 02 •47 842535 4 49 157465 10 5i 9-756963 3 02 9-gi4i58 •47 9.842805 4 49 10-157195 8 52 757144 3 02 914070 913982 •47 843074 4 49 156926 53 757326 3 02 •47 843343 4 49 i5665 7 156388 54 757507 757688 3 02 913894 ■47 843612 4 % 55 3 01 9i38c5 ■47 843882 4 i56n8 5 56 757869 3 01 913718 •47 844i5i 4 48 155849 4 u 758o5o 3 01 9i363o < •47 844420 4 48 , l555bo 3 75823o 3 01 913541 •47 844689 4 48 1 553 1 1 1 5 9 75841 1 3 01 913453 ■47 844958 4 48 1 55o42 ■ 60 758591 3 01 9 i3365 ■47 846227 4 48 154773 M. Cosine D. Sine 55° Cotang. D. T»pg. SINES AND TANGENTS. (35 DEGREES. ) 53 Sine D. Coaiua D. Tang. D. Cotangl 60 9-758591 3 01 9'9i3365 ■47 9-846227 4-48 10-154773 I 708772 3 00 913276 913187 :S 845496 4.48 1 545o4 5 9 2 758 9 5a 3 00 845764 4.48 154236 58 3 759132 3 00 913099 ■48 846o33 4-48 153967 153698 1 53430 ll 4 7593 1 2 3 •00 9i3oio ■48 846302 4.48 5 759492 3 •00 912922 912833 •48 846570 4-47 55 6 759672 2 •99 -48 846839 4-47 i53i6i 54 I 759862 2 ■99 912744 •48 847107 4-47 152893 53 76oo3i -2 ■99 912655 -48 847376 4-47 152624 52 9 760211 2 •99 912566 -48 847644 4-47 i5 2 356 5i 10 76o3oo 9.76056c 760748 2 -go 912477 ■48 847913 4-47 152087 5o II 2 •98 9-912388 ■48 9-848181 4-47 I0-i5.i8ig 49 12 2 .98 912299 •49 848449 4-47 i5i55i 48 i3 760927 2 •98 912210 • 49 848717 4-47 i5i283 47 14 761106 2 98 912121 •49 848986 •4-47 i5ioi4 46 i5 761285 2 % 9i2o3i ■49 849254 4-47 150746 45 16 761464 2 98 91 1942 •49I 849522 4-47 4.46 1 50478 44 \l 761642 2 97 9ii853 •491 849790 l5o2IO 43 76 1 821 2 97 911763 ■49 85oo58 4.46 I4g942 42 19 761999 2 97 9116741 •49 85o325 4-46 149675 41 20 762177 9-762356 2 97 91 1 584i •49 85o5 9 3 4-46 U9407 40 21 2 96 9-911495 ■49 9-85o86i 4.46 10-140139 14887 1 18 22 762534 2 911405 ■49 85 1 1 29 4.46 23 762712 762889 2 96 91 i3i5 •5o 85 1 3 9 6 4.46 148604 iz 24 2 96 911226 •5o 85i664 4-46 148336 25 763067 2 96 giii.36 •5o 85i 9 3i 4.46 148069 35 26 763245 2 96 91 1046, -5o 832199 4-46 147801 34 «7 763422 2 96 910966 910866 ■5o 852466 4.46 147534 33 28 763600 2 9 5 • 5o 852 7 33 4-45 147267 32 2g 763777 763954 2 9 5 910776 910686 1 ■5o 853ooi 4-45 146999 1467J2 3i 3o 2 9 5 •5o 853268 ' 4-45 3o 3i 9-764131 2 9 5 9-910596 •5o 9-853535 4-45 io-i46465 29 32 764308 2 9 5 9io5o6 ] •5o 853802 4-45 146198 i45g.1i 28 33 764485 2 94 910415 •5o 854069 4-45 27 34 764662 ' 2 94 . 9io325 1 ■ 5i 854336 4-45 U5664 26 35 764838 2 94 910235 1 ■5i 8546o3 4-45 145397 i45i3o 25 36 765oi 5 2 94 910144 ] • 5i 854870 4-45 24 37 765191 2 94 910054 1 ■5i 855i37 4-45 144863 23 38 765367 2 94 909963 1 •5i 855404 4-45 . 144596 22 3 9 765544 2 9 3 909873 1 909782 1 -9-909691 1 • 5i 8556 7 1 4.44- 144329 21 4o 765720 9-765896 2 93 •5! 855g38 4.44 J44062 20 4i 2 93 •5i 9-856204 , 4.44 10-143796 19 42 766072 2 93 909601 1 •5i 856471 4.44 I43520 143263 IS 43 766247 2 93 909510 1 •5i 866737 4.44 17 44 766423 2 9 3 909419 1 ■5i 857004 4.44 142996 142730 16 [ 45 766598 2 92 909328 1 •52 857270 4.44 i5 46 766774 2 92 909237 1 .52 85 7 537 4.44 142463 14 47 766949 2 92 909146 |i •52 8578o3 4-44 142107 I41Q.3 1 i3 J 48 767124 2 92 909055 'i ■52 808069 4.44 12 49 767300 2 92 908964I1 90887311 •52 858336 4.44 141664 11 5o 767475 2 9> •52 858602 4-43 141398 1 • 1 4 1 1 3 2 10. 5i 9-767649 2 9' 9.908781 1 ■52 9-858868 4.43 I 52 767824 2 9' 908690 1 ■52 859134 4.43 140866 53 767999 768173 2 9' 908599 1 ■52 859400 4-43 140600 I 54 2 9 1 908507 1 •52 85 9 666 4.43 ?4o334 55 768348 2 90 908416 1 ■ 53 859932 4-43 140068 5 56 768522 2 90 908324 1 • 53 860198 4-43 139802 4 Si 768697, 2 90 908233 1 ■ 53 860464 4-43 139536 3 : 768871! 2 90 908141 1 • 53 860730 4.43 139270 2 5 9 769045; 2 90 908049 1 •53 860995 4-43 139005 138739 1 6o 76921 Jj 2-90 907958 1 • 53 861261 4-43 Cosine I D. Sine* J .4° Cotang D. -Tang. M. 64 (3C DEGREES.) A TABLE OF LOGARITHMIC ;il Sine 0. Cosine j D. >Tang. D. Cotang 60 9.769219 76939J 2-90 9 -9079581 1 -53 9-861261 4-43 10-138739 138473 i 2 89 907866'! 53 861 527 4 43 n 2 769566 2 89 9°7774|i 53 861792 4 42 138208 3 769740 2 89 907682,1 53 8620S8 4 42 137942 5 j 4 769913 2 89 907590 1 53 862323 4 42 137677 56 5 770087 2 89 907498; 1 53 86258 9 4 42 137411 55 6 770260 2 88 907406 1 53 862854 4 42 137146 54 I 770433 2 88 9073 14' 1 54 863 119 863385 4 42 i3688i 53 770606 2 88 907222:1 54 4 42 i366i5 5a 9 770779 2 88 907129 1 54 86365o 4 42 1 3635o 5i 10 770952 2 88 907037 1 54 8639 1 5 4 42 i36o85 5o n 9-771125 2 88 9-906945 1 906852 1 54 9-864180 4 42 io-i3582o % 12 771298 2 87 54 S64445 4 42 135555 lJ 77U70 2 87 906760 1 54 864710 4 42 135290 % u 771643 2 87 906667 1 54 864975 4 41 i35o25 i5 77i8i5 2 87 906S7S1I 54 865240 4 4i 134760 45 16 771987 2 87 906482 1 54 8655o5 4 41 1 344o5 1 34230 44 13 772159 2 87 906389 1 55 865770 4 41 43 77233i 2 86 906296 1 55 866o35 4 41 i33 9 65 42 '9 7725o3 2 86 900204,1 55 8663oo 4 41 133700 4i 20 772675 2 86 9061 ii|i 55 866564 4 41 133436 40 21 9-772847 773018 2 86 9-906018 1 55 9-866829 4 41 10-133171 ll 22 2 86 9o5o25!i 905832 1 55 867094 86 7 358 4 41 132906 23 773190 2 86 55 4 4i 132642 37 24 77336i 2 85 9o573o, 1 905640 ji 55 867623 4 4i 132377 36 25 773533 2 85 55 867887 4 41 i32n3 35 ' 26 773704 2 85 905552 1 55 868 1 52 4 4o 131848 34 ll 7 7 38 7 5 " 2 85 905459' 1 55 868416 4 4o i3i584 33 774046 2 85 9o5366ji 56 868680 4 4o i3i32o 32 I 9 774217 2 8.S 905272,1 56 868945 4 4o i3io55 3i 3o 774388 2 84 905179! 1 9-9o5o85ji 56 869209 9-869473 4 4o 130794 3o 3i 9-774558 2 H 56 4 40 io-i3o527- 29 32 774729 774899 2 84 904092 1 56 8697,37 4 40 1 3o263 28 33 2 84 904898 56 870001 4 40 129999 129735 27 34 775070 2 84 904804 56 870265 4 40 26 35 775240 2 84 9047 1 1 904617 56 870529 4 4o 1 2947 1 25 36 775/, 10 2 S3 56 870793 871037 4 40 129207 24 12 77558o 2 83 904523 1 56 4 40 1 28943 23 775750 2 83 904429 904335 57 8 7 i32i 4 40 128679 22 • h 775920 2 83 57 87i585 4 40 I284i5 21 4o 776090 2 83 904241 57 871849 4 3 9 I28i5i 20 4' 9-776209 2 83 9-904147 57 9-872112 4 3 9 10-127888 ;g 42 776429 776598 2 !-2 904o53 57 872376 4 3g 127624 43 2 82 9o3g59 903864 57 872640 4 39 127360 17 44 776768 2 82 57 872903 4 39 127097 16 45 776937 2 82 903770 57 873167 4 39 126833 i5 46 777106 2 82 903676 57 87343o 4 39 126570 14 3 777275 2 81 9o358i 57 873694 873957 4 3 9 1 263o6 ■ 3 777444 2 81 903487 57 4 3 9 1 26043 12 P 777613 2 81 903392 58 874220 4 3 9 125780 u 5o 77778i 2 81 903298 58 874484 4 3 9 I255i6 10 5i 9-777950 2 81 9-9o32o3 58 9-874747 4 3 9 io- 125253 8 i2 778119 2 81 903108 58 875010 4 3 1 24990 '.3 778287 2 80 9o3oi4 58 875273 4 124727 I '>i 778455 2 80 902919 902824 58 875536 4 38 1 24464 55 778624 2 80 58 875800 4 38 124200 5 ;* 778792 2 80 902729 58 876063 4 38 123937 4 ll 778960 2 80 902634 58 876326 4 38 1 23674 3 77912b 2 80 902539 5 9 876589 4 38 1 23411 2 5 9 779295 2 79 902444 5 9 876851 4 38 I 23 1 49 ■ 6o 779463 2-79 902349 1^9 877114 4-38 122886 _M. r~ Cosine J). Sine 53° Cotang. D. Tang. SINKS AND TANGENTS. (37 DEGREES.) 55 M. o Bins D. Cosine j D. Tang. D. | Cottng. 60 9-779463 a-79 c ■ 902349 1 - 59 902253 1 -69 9-877114 4-38 10-122886 i 779631 2-79 877377 4-38 122623 it a 779798 •3.- 79 902i58,i -59 877640 4-38 122360 3 779966 2-79 902063,1 -59 877903 4-38 122097 1 21 835 s 4 7Soi33 2-79 901967 J 1 -59 901872 1-59 8 7 8i65 4-38 56 5 780300 2-78 878428 /■38 121572 55 6 780467 2-78 901776 901681 1-59 878691 878953 4-38 121309 54 7 780634 2-78 1 -59 4-37 121047 53 8 780801 2-78 90 1 585 1-59 879216 4-37 120784 5a 9 780968 2-78 901490 1 -5g 879478 4-37 120522 5i 10 78i'i34 2-78 901 3 9 4 i-6o 879-41 4-37 120259 5o ii q-78i3oi 2-77 9-901298:1-60 9-88ojo3 4-37 10-119997 49 12 781468 a- 77 901202 i-6o 880265 4-3T 119735 48 i3 ■78-634 2-77 901 106 I- 60 8So528 4-37 119472 47 14. 781800 2-77 901010 i-6o (480790 8Sio52 4-37 119210 46 ' 15 781966 2-77 900914 I- 60 4-37 118948 45 16 782132 2-77 9O0818 I- 60 88i3i4 4-37 1 1 8686 44 "7 ,- 782298 2-76 900722 i-6o 88 1 5 7 6 4-37 1 1 8424 43 18 782464 2-76 900626 i-6o 881839 4-37 118161 42 19 •j82630 2-76 90o52o 1 -6c 882101 4- 3 7 1 17899 117637 41 20 782796 2-76 900433 i-6i 882363 4-36 40 21 9'78296l 2-76 9-900337 i-6i 9-882626 4-36 10-117375 ll 22 783:27 2-76 900240 1-61 882887 883i48 4-36 1 171 13 23 783292 733458 2-75 900144 f -61 4-36 1 1 6852 37 24 2-75 900047 899951 899854 i-6i 883410 4-36 1 16590 36 25 7 83623 2-75 1-61 883672 4-36 n6328 35 26 783 7 8g 2-75 1-61 883934 4-36 1 16066 34 3 783953 2-75 8997J7 1 -61 884196 884457 4-36 n58o4 33 7841 ft 2-75 899660 i-6i 4-36 115543 32 29 784282 2-74 899564 1-61 884719 4-36 , Ii528i 3i 3o 784447 2-74 899467 1-62 884980 4-36 Il5o20 3o 3i 9-784612 2-74 9-899370 1-62 9-885242 4-36 I0-H4758 ■29 32 784776 2-74 899273 1-62 8855o3 4-36 1 14497 28' 33 784941 2-74 899176 1-62 885 7 65 4-36 II4235 2 Z 34 .785 1 o5 2-74 899078 898981 1-62 886026 4-36 1 13974 26 35 785?6g 2 = 73 1 -62 886288 4-36 113712 25 36 785433 2-73 898884 1-62 886549 4-35 1 1 3454 24 Si 785597 2- 7 3 898787 1-62 886810 4-35 113190 23 785761 * 2-73 898689 1 -62 887072 4-35 1 1 2928 22 3 9 .785925 i- 7 3 898592 1-62 887333 4 r 35 1 1 2667 21 40 786089 2-73 898494 I-.63 887594 9.887855 4-35 1 1 2406 ao 41 9-786252 2-72 9-898397 1-63 4-35 io-H2i45 \l 42 7864:6 2-72 898299 1-63 8881 16 4-35 .111884 43 786579 2-72 898202 1-63 888377 4-35 1 1 1623 \l 44 786742 2-72 898104 1-63 88863 9 4-35 1 1 i36i 45 786906 2-72 898006 1-63 £88900 4-35 IIIIOO i5 46 787069 2-72 897908 1-63 889160 4-35 1 1 0840 1 4. 47 787232 2-71 897810 1-63 ' 889421 4-35 1 1057c i3 48 787395 2-71 8977 1 2 1-63 889682 4-35 Iio3ic 12 g 787567 2-71 897614 1-63 889943 4-35, Iioo5- 11 787720 2-71 897516 1-63 89020^ 4-34 10979^ -10- 10953^ 10 5i 9-787883 788045 2-71 9-897418 1-64 9-89046' 4-34 9 52 2-71 897320 1-64 890725 - 4-34 109275 53 788208 2-71 897222 1-64 890986 4-34 109014 I. 54 788370 2-70 89712; 1-64 891247 4-34 10875; 55 7 88532 ' 2-70 897025 1-64 891 5o- 4-34 108490 io8a32 5 56 78869/ 788856 2-70 896926 1-64 891768 4-34 4 % 2-70 896828 1-64 89202S '4-34 107972 3 789018 2-70 896729 1-64 892289 4-34 107711 3 H 789180 2-70 896631 1-64 892549 4-34 lo-J45i I 789342 2-69 896532 1-64 52° 89281c 4.34 10719c Cosire D. Sine 1 Cotang. D. Tang. M. 66 (38 DEGREES.) A TABLE OF LOGARITHMIC M. Sine 19 20 21 22 23 24 25 26 u ll 3i 32 33 34 35 36 ll 3 9 4o 41 4S 43 44 45 46 % % 5i 52 53 54 55 56 % 9-789342 789504 789665 789827 D. 790149 7903 10 790471 790632 790793 790954 9-791 1 i5 791275 791436 79i5o6 791767 791917 792077 792237 792397 792557 9-792716 792876 793o35 793195 793354 79?5i4 793673 7g3832 793991 794130 9-794308 794467 794626 794784 794942 795101 795259 795417 795575 7 9 5733 9-7 9 58 9 i 796049 796206 796364 796521 796679 796836 796993 797i5o 797307 9-797464 797621 191111 797934 798091 798247 7 9 84o3 7g856o 798716 798872 2-69 2-69 2-69 2-69 2-69 2-69 2-68 2-68 2-68 2-68 2-68 2-68 2-67 2-67 2-67 2-67 2-67 2-67 2-66 2-66 2-66 2-66 2-66 2-66 2-65 2-65 2-65 2-65 2-65 2-65 2-64 2-64 2-64 2-64 2-64 2-64 2-64 2-63 2-63 2-63 2-63 2-63 2-63 Cosine 63 2-62 2-62 2-62 2-62 2-62 2-6l 2-6l 2-6l 2-6l 2-61 2-6l 2-6l 2-6l 2- 60 2-60 S-6o 2-60 9-896532 896433 896335 896236 896137 896038 895939 895840 895741 895641 895542 9-895443 895343 895244 895145 895045 894945 894846 894746 894646 894546 9-894446 894346 894246 894146 894046 893946 893846 893745 893645 893544 •893444 893343 893243 893142 893041 892940 892839 892739 8 9 2638 892536 • 892430 892334 892233 892132 892030 891929 891827 891726 891624 891523 •891421 891319 891217 891115 891013 89091 1 890809 Tang. 1-64 1-65 1-65 -65 1-65 1-65 • 65 • 65 1-65 1-65 1-65 66 1-66 1-66 1-66 1-66 1-66 1-66 1-66 1-66 1-66 ,.67 ,.67 1-67 1.67 1.67 67 1. 67 1-67 67 67 1-68 1-68 • 798 1 Cosine | D. 1-68 !-68 1-68 1-68 1-68 1-68 1-68 1-69 1-69 1.69 1 -69 1 -69 1-69 1-69 1-69 1-69 70 1-70 •70 ■70 • 70 ■7° ■70 .y --1° 890707 1-70 890605 1-70 89o5o3 1-70 Sine 51° 1-892810 893070 8 9 333 1 893591 8 9 385i 894111 894371 894632 895152 895412 1-895672 8 9 5 9 32 8961. 8964 896712 89697 1 89723 89749 897751 898010 ;■ 898270 898530 D. 89904' 89930' 899568 '899827 900346 goo6o5 9-900864 901 1 24 90i383 901642 901901 902160 902419 902679 902938 903197 9-903455 903714 903973 904232 904491 904750 900008 905267 905526 905784 9 • 906043 906302 906560 906819 907077 907336 907594 907802 9081 1 1 908369 4-34 4-34 4 -.3-4 4-34 4-34 4-34 4-34 4-33 4-33 4-33 4-33 4-33 4-33 4-33 4-33 4-33 4-33 4-33 4^33 4-33 4-33 4-33 4-33 4-33 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32 4-32' 4-32 4-3i 4-3i Cotanpr. Cctung. •3i ■3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3i 4-3o 4-3o 0-107190 106930 106669 106409 106149 105889 105629 105368 io5ro8 104848 104588 10-104328 104068 io38o8 io3548 103288 103029 102769 102509 102249 101990 0-101730 101470 101211 100951 100692 100442 100173 099014 099654 ~ i5 - -A ib 098876 098617 o 9 8358 098099 097840 097581 097321 097062 096803 10-096545 096286 096027 095768 095509 095250 094992 094733 094474 094216 10-09395' 09369! 093440 093 181 092023 092664 092406 092148 091889 09163 09939! io-o99i3< 60 u 55 54 53 52 5i So t % 45 44 43 42 41 40 ll ll 35 34 33 32 3i 3o It 25 24 23 22 21 20 18 '7 16 i5 14 i3 12 D. Tang. M. 8INES AND TANGENTS. (39 BEOREES.] 57 M. Sine D. Cosine D. Tang. D. Cotimg. .' o 0-798872 2-6o 9 -890503 • 70 9'9o83t9 908628 4-3o 10-091631 60 i 799028 2- 60 890400 •71 4-3o 091372 .S 2 799184 2 00 890298 •7 1 908886 4-3o 091114 3 799339 2 5 9 890195 •T 909144 4-3o 090856 5 7 4 799493 7996D1 2 5 9 890093 •7< 909402 4-3o 090598 56 5 .2 5 9 889990 889888! ■7' 909660 4-3o 090340 55 6 799806 2 5 9 ■7' 909918 4-3o 090082 54" •2 799962 8001 17 2 5 9 889785 ■7" 9101-77 4-3o 089823 53 2 5 9 . 889682 [•71 910435 4-3o 089565 52 9 800272 2 58 889579 •71 9io6o3 ' 910961 4-3o 089307 5i 10 800427 2 58 889477. [•71 4-3o , 089049 10-088791 088533 5o , ii 9 -800582 2 58 9-889374 [■72 9-911209 4-3o 49 12 800737 2 58 889271! [•72 911467 4-3o 48 . i3 800892 2 58 889168 [-72 911724 4-3o 088276 % 14 801047 2 58 889064 1-7? 911982 4-3o 088018 i5 801201 2 58 888961 1-72 912240 4-3o 087760 45 16 80 1 356 2 57 888858 '•72. 9 1 2498 912706 4-3o 087502 44 '7 8oi5ii 2 57 888755 1-72 4-3o 087244 43 IS 80 1 665 2 57 888651 1-72 913014 4-29 086986 42 >9 801819 801973 2 57 888548 1-72 913271 4-29 086729 41 20 2 57 888444 i- 7 3 913529 4-29 086471 40 21 9-802128 2 57 9-888341 i- 7 3 9-9U787 4-29 10-086213 1 22 802282 2 56 888237 i- 7 3 914044 4-29 085956 23 802436 2 56 888 1 34 .. 7 3 914302 4-29 ,085698 37 24 8o258o 802743 2 56 888o3o 1-73 914060 4-29 '085440 36 25 2 56 887926 887822 1-73 914817 4-29 o85i83 35 26 802807 8o3o5o 2 56 i- 7 3 91 5o75 4-29 084925 34 =7 2 56 887718 1.73 9i5332 4-29 084668 33 28 8o32o4 2 56 887614 !- 7 3 915590 4-29 084410 32 29 8o3357 2 55 88 7 5io 1.73 915847 ' 4-29 o84i53 3l 3o 8o35u 2 55 . 887406 1-74 .916104 . 4-29 083896 10 •o83638 3o 3i g-8o3664 2 55 9-887302 1-74 9-916362 4-29 11 32 8o38i7 2 55 887198 1-74 916619 4-29 o8338i 33 803970 2 55 887093 1-74 916877 4-29 o83i23 =7 3 4 804123 2 55 886989 886885 1-74 9'7'34 4-29 082866 26 35 804276 2 •54 1-74 917391 4-29 082609 25 36 804428 2 •54 886780 1-74 917648 4-29 o82352 24 ii 8o458i 2 •54 886676 i-74 917905 4- 29 4-28 082095 081837 23 804734 804886 2 .54 886571 1-74 918163 22 3 9 2 •54 886466 1-74 918420 4-28 o8i58o 21 4o 8o5o39 2 •54 886362 1 -75| 918677 4-28 o8i323 20 4i 9-805191 2 •54 9.886257 1-75 9-918934 4-28 10-081066 !S 42 8o5343 2 -53 886i52 i- 7 5 919191 4-28 080809 43 8o5495 2 • 53 886047 ,- 7 5 .919446 4-28 o8o552 '7 44 8o5647 2 ■ 53 88 5 9 42 i- 7 5 919705 4-28 080295 o8oo38 16 45 805799 2 -53 885837 i. 7 !j 919962 2-28 i5 46 805961 2 ■53 885732 L75 920219 4-28 079781 r4 4? 806 1 o3 2 • 53 885627 !. 7 5 920476 4-28 079S24 i3 48 806254 2 • 53 885522 i- 7 5 920733 4-28 079267 12 49 806406 2 •52 8854i6 i- 7 5 920990 4-28 079010 078753 11 5o 806557 2 •52 8853 1 1 1.76 92124-; 4-28 10 5i 0-806709 806860 2 •52 9-885205 1.76 9-92i5oc 4-28 10-078497 I '52 2 •52 885 1 00 1-76 921760 4-28 078240 53 80701 1 2 •52 884994 884889 884783 i. 7 6 922017 4-28 077983 7 54 807163 2 •52 1.76 922274 4-28 077726 6 55 807314 2 •52 1.76 92253o 4-28 077470 5 56 807465 2 • 5i 884677 1.76 922187 4-28 077213 4 3 tl 807615 2 • 5i 884572 1.76 923o4i 4-28 076956 807766 2 • 5i 884466 1.76 9233oo 4-28 076700 2 5o 807917 808067 2 •5! 88436o 1.76 923557 4-27 07644c 1 66 2 •5i 884254 i;77 9238i3 4-27 D. 076187 Cosine D. Sine 50° Cotang. Tang. M.j 58 (40 DEGREES.) A TABLE OF LOGARITHMIC M. Sine D. •9 S3 U 25 26 27 28 ?9 3o 3i 32 33 34 35 36 ll 3 9 40 4i 42 43 44 45 46 % £ Si 52 53 54 55 56 u 0-808067 808218 8o8368 ' 8o85i 9 803669 808819 809119 809269 809419 809561 9-80971 810017 810167 8io3i6 8io465 810614 810763 810912 811061 9-811210 8u358 8u5o7 8u655 81 1 804 811952 81 2 100 812248 812396 812544 9-812692 812840 812988 8i3i35 8i3283 8i343o 8i35 7 8 813725 8i38 7 2 814019 9-814166 8i43i3 814460 814607 8i47.53 814900 8 1 5o46 815193 8i533( 81 548 9-8i563 815778 815924 816069 81621$ 8i636i •8i65o7 8i6652 816798 816943 Cosine 2-5l 2-5l 2-5l 2-5o 2-5o 2-5o 2-5o 2-30 2-5o 2-49 2-49 2-49 2-49 2-49 2-4g 2-48 2-48 2-47 2-47 2-47 2-47 2-47 2-47 2-47 2-46 2.46 2-46 2-46 2-46 2-46 2-46 2-45 2-45 2-45 2-45 2-45 2-45 2-45 2-44 2-44 2-44 2-44 2-44 2-44 2-44 2-43 2-43 Cosine D. • 43 •43 ■ 43 ■43 •43 •42 •42 •42 2-42 9-884254 884148 884042 883o36 883829 883 7 23 8836n 8835io 883404 883297 883 191 9 -883084 882977 882871 882764 882657 88255o 882443 882336 882229 882121 9-882014 881907 881799 8816 881 5 . 881477 881369 881261 88u53 881046 9 -880938 88o83o 880722 880613 88o5o5 880397 880289 880180 880072 87996.3 9-879855 879746 879637 879529 879420 8793 1 1 879202 879093 878984 878875 9-878766 878656 878547 878438 878328 878219 878109 877999 877890 877780 1-77 1-77 1.77 1.77 1-77 '■77 '•77 '•77 7 2 78 t 1.78 1.78 78 1-78 78 '•79 1-79 '•79 '■79 1.79 '•79 '■79 '•79 '■79 79 1.80 I-.8o i-8o I-8o i-8o 80 i-8o 80 80 1-8 1-8 1-8 i-8 i-8 i-8 1-8 1-8 1-82 1.82 1-82 Tang. 9-9238i3 924070 924327 924583 924840 925096 925352 925609 925865 926122 926378 9.926634 Sine 49° D. Ootang. 1-82 82 1-82 ■82 1-82 1-82 1-83 1-83 1-83 1-83 1-83 927U7 927403 927639 927915 928171 928427 928683 928940 9-929196 929452 929708 929964 930220 93o475 930731 930987 93i243 931499 9-931755 932010 932266 932522 932778 -933033 933289 933540 9338oo 934066 9-934311 , 934567 934823 935078 935333 935589 935844 g36l .10 g 36355 936610 936866 937121 937376 937632 937887 938142 9383 9 8 9 38653 938908 939163 Cotang. 10-076187 075930 075673 075417 075160 074904 074648 074391 074i35 073878 073622 10-073366 073110 072853 072597 072341 072085 071829 071573 071317 071060 10 070804 070548 070292 070036 069780 069025 069269 0690 1 3 068757 068001 o-.o68245 067990 067734 067478 067222 066967 066711 066455 066200 065944 io-o65689 065433 065177 064922 064667 06441 1 0641 56 063900 063645 o633oo !0'o63i34 062879 062624 062368 062113 06 1 858 061602 061347 061092 0608J7 60 3 50 55 54 53 52 ■5 1 5o % t 45 44 43 42 41 40 18 37 36 35 34 33 32 3i 3o % 27 26 25 24 23 22 21 20 lo !o i5 14 i3 12 n 10 _T2££_ M. 67NES AND TANGENTS. (41 DKGKEKS. k r 5 [W. Sine 1 T>. Cosine [ D. Tang. D. Cotang. c 0-816943 2-42 9. 877780' 1 -83 9-939163 4-25 10-060837 60 1 817088 2 42 877670 1 83 939418 4 25 060682 59 2 817233 2 42 877560 1 83 939673 4 25 060327 58 3 817379 2 42 877450,1 83 9.39928 4 25 060072 -57 4 817524 2- 41 8773401 83 940183 4 25 059817 06 5 817668 2 41 8772301 84 940438 4 25 059562 55 6 817813 2 41 877120' 1 84 940694 4 25 069306 54 I 817958 2 41 877010! 1 84 940949 4 25 o5oo5i 53 8i8io3 2 41 8768991 84 941 204 . 4 25 058796 52 9 818247 2 41 8767891 8766781 84 94S458 4 25 058542 5i 10 8i83o2 o.8i8536 2 41 84 94m4 4 25 058286 5o ii 2 40 9. 876568' 1 84 9-041968 4 25 I0-o58o32 % 13 818681 2 40 876457 1 84 9422'i3 4 25 057777 i3 818825 2 40 876347.1 84 942478 4 25 057622 47 i4 818969 819113 2 40 876236.1 85 942733 4 25 067267 46 •5 2 40 876125,1 85 94^988 4 25 057012 45 16 819257 2 40 876014 1 85 943243 4 25 066757 44 \l 819401 2 40 875904 1 85 943498 943722 4 25 056502 43 819645 2 39 875793,1 85 4 25 056248 42 19 819689 2 39 875682|i 85 044007 4 25 055993 055738 4i 20 819832 2 39 8 7 55 7 ii 85 944262 4 25 40 21 9-819976 2 3 9 9. 875459 [ 1 85 9.944517 4 25 10-055483 ll 22 820120 2 3 9 875348,1 85 944771 4 24 055229 23 820263 2 3 9 875237' 1 85 945026 4 24 054974 ?"» 24 820406 2 ll 875126 1 86 945281 4 24 054719 05446S 35 25 82o55o 2 875oi4'i 86 945535 4 24 35 26 820693 820836 2 38 874903 ' 1 86 945790 4 24 ■054210 34 3 29 • 2 38 87479' !i 86 946045 4 24 053955 33 820979 821122 2 2 38 38 874680;! 874568 1 86 86 946299 946554 4 4 24 24 053701 053446 32 3i 3o 821265 2 38 8744561 86 946808 4 24 053192 3o 3i 9-821407 2 38 ' 9 -874344' 1 86 9-947063 4 24 10-052937 29 32 82i55o 2 38 874232J1 87 9473 18 4 24 052682 28 33 821693 2 37 874121 1 87 947572 4 24 062428 27 34 82i835 2 37 874009 1 87 947826 4 24 052174 26 35 821977 2 37 8738 9 6ji 87 948081 4 24 051919 25 36 822120 2 37 873784 1 87 948336 4 24 o5i664 24 37. 822262 2 37 873672 1 87 948590 4 24 o5i4io 23 38 822404 2 37 873560 1 87 948844 4 24 05n56 22 3 9 822546 2 ll 873448 ; i 87 949099 949353 4 24 000901 21 40 822688 2 8 7 3335;i 87 4 24 050647 20 41 9-822830 2 36 9-873223,1 87 9-949607 4 24 io-o5o393 o5oi38 :g 42 822972 2 36 8731 10 1 88 949862 4 24 43 823114 2 36 872998 88 9501 16 4 24 049884 '7 44 823255 2 36 872885 88 950370 4 24 049630 16 45 823397 2 36 872772 1 88 950625 4 24 049375 i5 46 823539 2 36 872659' 1 88 950879 q5i i33 4 24 049121 048867 14, 5 82368o 2 35T 872547:1 88 4 24 i3 823821 2 35 87243411 88 , 9 5 1 388 4 24 048612 12 49 823963 2 35 872321 1 ! 88 951642 4 24 048358 11 5o 824104 2 35 87220811 88 961896 4 24 048104 10 5i 9-824245 2 35 9-872005 I 89 9-952160 4 24 10-047850 I 52 824386 2 35 871981 I 89 9524o5 4 24 047595 53 824527 S24668 2 35 871868 I 89 902659 952913 4 24 047341 7 54 2 34 871755 I 89 4 24 047087 6 55 824808 2 34 871641'! 89 953167 4 23 046833 5 56 - 824949 2 34 871528 I 89 953421 4 23 •046679 4 u 825090 2 34 871414 I 89 953675 4 23 046323 3 825230 2 34 87'i3oi!i 89 953929 954183 4 23 046071 2 5 9 825371 2 34 8711871 89 4 23 045817 I 60 8255i 1 2 34 871073 1 90 954437 4-23 045563 Cosine IX Sine |4 8° Ootong. 0. Tang. .«L 25 80 (42 DEUREES.) A rABLE OF "LOGARITHMIC M. Sine D. Cosine | D. | Tang. D. Cotang. 9-8255II 2-34 9-871073 1-90! 9-964437 4 23 10-045563 60 i 825651 2 33 870960' 1 870846'! 90 964691 4 23 o453oo o45o55 ol 2 825791 825931 2 33 90 954945 4 23 3 2 33 870732 1 90 955200 4 23 044800 n 4 826071 2 33 870618 1 90 955454 4 23 044546 5 826211 2 33 8-jo5o4 90 955707 4 23 o442o3 o44o3o 043785 55 6 82635i 2 33 870390 90 955961 4 23 54 I 826491 2 33- 870276 90 9562i5 4 23 53 82663i 2 33 870161 90 956469 95672J 4 23 o43 53 1 5s 9 826770 2 32 870047 9 1 4 23 043277 5i 10 826910 2 32 869933 9 1 956977 4 23 043023 /5o ii 9-827049 2 32 9-869818 9i 9 - 9 5 7 23i 4 23 10-042769 0425i5 3 12 827189 2 32 869704 9' 9 5 7 485 4 23 ■ 3 827328 2 32 869589 9' 967739 9M993 4 23 042261 47 14 827467 2 32 869474 9 1 4 23 042007 46 i5 827606 2 32 869360 91 968246 4 23 041764 45 16 827745 2 32 869245 9 1 9585oo 4 23 o4i5oo 44 \l 827884 2 3i 86gi3o 1 91 958754 4 23 041246 43 828023 2 3i 869015 92 959008 4 23 040992 040738 42 '9 8^162 2 3i 868900 92 959262 4 23 41 20 8283oi 2 3i - 868785 92 969616 4 23 040484 40 21 9-828439 2 3i 9-868670 92 9-959769 960023 4 23 10 -04023 1 3 22 8285 7 8 2 3i 868555 92 4 23 039977 23 828716 828855 2 3i 868440 92 960277 4 23 039725' 37 24 2 3o 868324 92 96o53* 4 23 039469 36 23 828993 829 i3i 2 3o 868209 92 960784 4 23 o3o2i6 35 26 2 3o 868o 9 3 92 961038 4 23 038962 34 11 829269 2 3o 867978 9 3 961 291 4 23 038709 038455 33 829407 2 3o 867862 9 3 961545 4 23 32 2 9 829545 2 3o 867747 93 961799 962052 4 23 038201 3i 3o 829683 ' 2 3o 867631 9 3 4 23 037948 3o 3i 9-829821 2 29 9-8675i5 9 3 9-962306 4 23 10-037694 8 32 829959 2 29 867399 867283 93 962560 4 23 037440 33 83oog7 83o234 2 29 9 3 962813 4 23 037187 11 34 2 29 867167 93 963067 4 23 036933 35 83o372 2 29 867051 93 963320 4 23 o3668o 25 36 83o5o9 2 29 866o35 94 963574 4 23 036426 24 11 83o646 2 29 866810 866703 94 963827 4 23 o36i73 23 830784 2 29 94 964081 4 23 035919 035665 22 3 9 830921 2 28 866586 94 964335 4 23 21 40 83io58 2 28 866470 94 964588 4 22 o354i2 20 4f 9-63i 195 83 1 332 2 28 9-866353 94 9-964842 4 22 io-o35i58 19 42 2 28 866237 94 965095 4 22 034906 18 43 83 1 469 2 28 866120 94 965349 4 22 o3465i \l 44 83 1 606 2 28 866004 9 5 965602 4 22 034398 ■45 83n42 83 1879 2 28 865887 9 5 9 65855 4 22 o3'ii45 i5 46 2 28 865770 9 5 966105 4 22 033891 033638 14 47 832oi5 2 27 865653 9 5 966362 4 22 i3 48 832i52 2 2 7 865536 95 966616 4 22 033384 12 49 832 288 2 27 865419 9 5 966869 4 22 o33i3i n 5o 832425 2 2 7 8653o2 9 5 967123 4 22 032877 10 5i 9-83256i 2 2 7 9-865i85 9 5 9-967376 4 22 10-032624 8 52 833697 2 2 7 865o68 9 5 967629 4 22 o3237i 53 832833 2 2 7 864950 864833 9 5 967883 968136 4 22 032117 7 54 832969 2 26 96 4 22 o3 1 864 6 55 833iod 2 26 864716 96 968389 968643 4 22 o3i6u 5 56 833241 2 26 8645o8 864481 96 4 22 o3i357 4 U 853377 2 26 96 968896 4 22 o3no4 3 833512 2 26 864363 96 969149 96940J 4 22 o3o85i 2 59 833648 2 26 864245 96 4 22 030597 1 60 i. 833783 5.26 864127 96 969656 4 22 o3o344 Cosine n^ D. Pine 4T° Cotana. ~"D. TaUK- M. BINEP j»ND TANGENTS. (43 DEGREES. 1 61 M. Sins I D. Cosine | D. Tan?. D. Cotoncj, ~6o~ 9-833783 2-26 9-864127 1-96 9 ■ 969656 4-22 io-o3o344 I 833919 2 20 864010 1 96 969909 '4 22 030091 5 9 2 834054 2 23 863892 1 97 970162 4 22 029838 58 3 834l8o 2 25 863774 1 97 970416 4 22 029584 07 4 834325 2 23 863656 1 97 970669 4 22 029331 56 5 834460 2 •25 863538 1 97 970922 4 22 029078 028825 55 6 8345o5 834730 2 25 • 863419' 1 97 971175 4 22 54 7 2 25 8633o 11 97 971429 4 22 028571 53 8 834865 2 25' 863 1 83 1 97 971682 4 22 0283 1 8 52 9 834999 835 1 34 2 24 863o64i 97 971935 4 22 028065 5i 10 2 24 8629461 98 - 972188 4 2: 027812 5o ii 9.835269 2 24 9-862827 1 98 9-972441 4 2! 10-027559! 49 O273o6| 48 12 835403 2 24 8627094 98 97269* 4 22 i3 835538 2 24 862590' 1 98 972948 4 22 027052! 47 14 835672 2 24 862471:1 98 973201 4 22 026799! 46 0265461 45 i5 835807 -. 2 24 862353' 1 98 973 '.54 4 22 ■ 6 835941 2 24 862234' 1 98 973707 4 22 0262931 44 \l 836o 7 5 2 23 8621 1 5 1 98 973960 4 22 026040 43 836209 836343 2 23 86io96!i 8618771 98 9742i3 4 22 025787 42 '9 2 23 98 974466 4 22 " 025534 41 20 836477 2 23 861758 1 99 974719 4 22 025281 40 21 9-8366H 2 23 9-86i638 1 99 9-974973 4 22 10 025027 39 22 836745 836878 2 23 861519 1 99 975226 4 22 024774 38 23 2 23 861400 1 99 970479 4 22 024521 37 24 837012 2 22 861280 1 99 975732 4 22 024268 36 25 807146 2 22 8611611 99 9 7 5g85 4 22 024015 35 26 837279 2 22 861041J1 99 976238 4 22 023762 34 27 83-7412 2 22 860922 1 860S02 1 99 976491 4 22 023509 33 28 83 7 546 2 22 99 976744 4 22 023256; 32 29 837679 2 22 860682 2 00 976997 977250 4 22 O23oo3 3i* 3o 837812 2 22 86o562 2 00 4 22 022750! 3o 3l 9 -837945 2 22 9 -860442! 2 00 9-977503 4 22 10.022497, 29 022244| 28 32 838o 7 8 2 21 86o322J2 00 977756 4 22 33 8382 1 1 2 21 860202 ! 2 00 978009 4 22 021991 27 021738; 26 021485 ,25 34 838344 2 21 860082 2 00 978262 4 22 35 838477 2 21 859962 2 859842 2 00 9 7 85i5 , 4 22 36 8386io 2 21 00 978768 4 22 021232 24 37 838742 2 21 859721 2 01 97902 1 4 22 020979' 23 38 838875 2 21 859601 '2 01 979 2 74 4 22 020726" 22 3 9 839007 2 21 859480 2 01 979527 4 22 020473, 21 4c 839140 2 20 85g36oJ2 01 979780 4 22 020220 20 41 9-839272 2 20 9'S592392 01 9-980033 4 22 10-019967! 19 42 839404 2 20 8591 19 2 01 980286 4 22 019714 10 43 83 9 536 2 20 808998 s! 01 g8o538 4 22 OI9462 17 44 839668 2 20 858877,2 01 980791 A 21 OI9209 10 45 839800 2 20 858756 2 02 981044 4 21 018956 i5 46 839932 2 20 858635,2 02 981297 981500 4 21 018703 14 47 840064 2 '9 8585i4 2 02 4 21 oi845o| 1 3 48 840196 2 '9 858393,2 02 981803 4 21 018197J 12 , 49 840328 2 ■9 858272 2 02 9S2056 4 21 017944 " 5o 840409 2 '9 858i5i!2 02 982309 4 21 017691; 10 10-017438, 9 017186. 8 016933! 7 5i 9-840591 2 '9 9-85802O2 02 9-982562 4 21 52 840722 2 ■9 857908,2 02 982814 4 21 53 840854 2 '9 857786,2 02 983067 4 21 54 840985 2 \l • 857665,2 o3 983320 4 21 016680 55 841116 2 807543 2 o3 9?35 7 3 4 21 016427 5 56 841247 2 18 857422 2 o3 983826 4 21 016174 4 57. 841378 2 18 807300:2 o3 984079 4 21 01 592 1 3 58 841509 2 18 8071782 o3 984331 4 21 010669 2 5g •841640 2 18 857o56l2 o3 984584 4 21 0i54i6 1 66 841771 2 18 - 856.;34 2-o3 984837 Cotang. 4 21 01 f 1 63 a Cosine D. sTiTi lie 5 D. Tariff. W-, 62 SINES AND TANGENTS. M. Sine D. Cosine •.«■ : Tang. D. Cotang. ■9-841771 2- 18 9-856o34 856812 2-03 9-984837 4-21 io-oi5i6; 60 I 841902 2-l8 2-o3 985090 4-21 014910 ■ 5o '58 2 842033 2-l8 856&O0 2-04 985343 4-21 614657 3 842163 2- 17 856568 2-0^ 985596 4-21 01440/ 57 4 842294 2-17 856446 2-0/1 985848 4 -2 1 014135 5ft S 842424 2-17 856323 2-Ot 986101 4-21 01389c 55 1 6 842555 2-17 856201 2-Oi 986354 4-21 013646 54 i 842685 2-17 856078 2-04 98660-; 4-21 013393 53 8428 1 5 2-17 855 9 56 855833 2-04 986860 4-21 oi3i4o 52 9 ■ 842946I 2-17 2-04 987112 4-21 a 1 2888 5i 10 843076| 2-17 9-8432o6| 2-16 855 7 ii 2-oJ 987365 4-21 012635 5o II 9-855588 2-o5 9-987618 4-21 10-012382 % 12 843336: 2- 16 855465 2-o5 987871 4-21 012129 i3 843466 2- 16 . 855342 2-o5 988123 4-21 011877 47 14 8435951 2- 16 855219 2-o5 988376 4-21 011624 46 15 S43t25 2' 16 843855 2- 16 855096 2-o5 988629 4-21 011371 -45 16 854973 2-oS 988882 4-21 011118 44 \l 843984 2-l6 85485o 2-o5 9S9134 4-21 010866 43 8441 14 2-l5 854727 2-o6 989387 4-21 oio6i3 42 '9 844243 2-l5 8546o3 2-o6 989640 4-21 oio36o 41 20 844372 2-l5 854480 2- 06 989893 4-21 010107 4o 21 9-844502 2- 15 9-854356 2-06 9-990145 4-21 10-009855 ll 22 844631 2l5 854233 2-o6 990398 99065 1 4-21 009602 23 844760 844889 845oi8 2l5 854109 2-06 4-21 009349 37 24 2l5 853g86 2- 06 990903 4-21 009097 36 25 2-lS 853862 2-o6 99ii56 4-21 008844 35 26 845i47 2l5 853738 2- 06 991409 4-21 008591 34 3 845276 2-14 8536U 2-07 991662 4-21 oo8338 33 845405 214 8534go 2-07 991914 4-21 008086 32 ■?9 845533 2-14 853366 2-07 992167 4-21 007833 3i 3o 845662 2-14 853242 2-07 992420 4-21 007580 3o 3i 9-845790 214 9-853u8 2-07 9-992672 4-21 10-007328 8 32 845919 2-14 852994 852809 2-07 992925 4-21 007075 33 846047 2-14 2-07 993178 4-21 006822 27 34 846175 2-14 852 7 45 2-07 99343o 4-21 006570 26 35 8463o4 2-14 852620 2-07 993683 . 4-21 006317 25 36 846432 2-l3 8524 9 6 2-08 993936 4-21 006064 24 33 84656o 2l3 8523 7 i 2-08 994189 4-21 oo58u 23 846688 2-l3 852247 2-08 994441 4-21 oo555o oo53oo 22 3 9 846816 2|3 852122 2-08 994694 4-21 21 4o 846944 2-l3 85ig 97 2-08 994947 4-21 do5o53 20 4i 9-847071 2-l3 9-85t8 7 2 2-08 9-995199 995452 4-21 10-004801 TO 42 847199 2-l3 85i 7 47 2-08 4-21 004548 l8 ' 43 847327 2-l3 85i622 2-08 995705 4-21 004295 \l 44 847454 212 85 1 497 2-09 995957 4-21 004043 45 847582 2-12 85i3 7 2 2-09 996210 4-21 003790 003537 i5 46 847709 847836 2-12 85 1 246 2-09 996463 4-21 U 1 % 2-12 85ii2i 2-09 996715 4-21 oo3285 i3 847964 2-12 830996 2-09 '850870' 2 -09 996968 4-21 oo3o32 12 f> 848091 212 997221 4-21 002779 11 5o 848218 2-12 850745:2-09 997473 4-21 002027 10 5i 9-848345 212 9-85o6i9'2-09 9-997726 4-21 10-002274 8 52 848472 2- II 830493,2-10 997979 4-21 002021 53 848599 2- 11 85o368J2-io 998231 4-21 001769 001016 6 54 848726 2- 1 1 850242 2-10 998484 4-21 55 848852| 2- II 85on6 2-10 998737 4-21 001263 5 56 848979, 2- II 849990 2-10 998989 4-21 001011 4 u 849106] 2- II 849864 2-IO 9-99242 4-21 000758 3 849232 2- II 849738 2-10 999495 4-21 ooo5o5 a 5g 849350 1 2 • 1 1 8494851 2- 1 1 84961 1!2> 10 999748 4-21 oooa53 1 Co 849485^ 2- I0 l 15°i 10-000000 4-21 10-000000 Cosine I D. 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