GIass__FL5j7 
 Book. 
 

 REPORT 
 
 OF 
 
 
 t/*f 
 
 LIEUT. COL. J. D. GRAHAM, 
 
 U. S. TOPOGRAPHICAL ENGINEERS, 
 
 ON 
 
 MASON AND DIXOiN'S IJNE. 
 
 ^STf^ITH Jk. 1SLA.F. 
 
 CHICAGO 
 
 1S63. 
 
ESSAGES 
 
 1' U O Jt THE 
 
 GOVERNORS OF MARYLAND AND PENNSYLVANIA, 
 
 TRANSMITTING THE 
 
 REPORTS OF THE JOINT COMMISSIONERS, 
 
 'I A N D O P 
 
 LIEUT. COL. GRAHAM, 
 
 U. S. TOPOGRAPHICAL ENGINEERS, 
 
 IN RELATION TO THE 
 
 INTERSECTION OF THE BOUNDARY LINES 
 
 OP THE STATES OF 
 
 MARYLAND, PENNSYLVANIA AND DELAWARE, 
 
 BEING 
 
 A PORTION OF MASON AND DIXON'S LINE. 
 
 WITH A MAP. 
 
 SECON-D EIDITIOISr. 
 
 CHICAGO: 
 
 STEAM PRESSES OF F. FULTON & CO. 
 1862. 
 

 BNTEEED ACCORDINa TO ACT OP UOKGRESS, DECEMBER 21, 1861, BY 
 
 LIEUT. COL. J. p. GRAHAM, 
 
 In the Clerk's Office of tue District Codrt of the United States for the Northern 
 District op Illinois. 
 
MASON AND DIXOFS LINE. 
 
 MESSAGE FROM THE GOVERNOR OP MARYLAND. 
 
 State Department, 
 Annapolis, Md., March 7th, 1850. 
 
 To THE General Assembly: 
 
 Henry G. S. Key, Esquire, of Saint Mary's county, was 
 appointed by me on the 21st of August last, a commis- 
 sioner under resolution No. 18 of December session, 1845, 
 to ascertain and refix, — in conjunction with Joshua P. 
 Eyre, Esquire, a commissioner appointed on the part of 
 Pennsylvania, and George Read Riddle, Esquire, a com- 
 missioner appointed on the part of Delaware, — certain 
 boundaries where the States of Maryland, Pennsylvania 
 and Delaware join each other. The commissioners have 
 performed this duty in a very able and satisfactory man- 
 ner ; and the accompanying report and papers,* and the 
 map of the boundaries adjusted and fixed by them, pre- 
 pared by Lt. Col. James D. Graham, of the U. S. Topi. 
 Corps of Engineers, detailed by the War Department for 
 this particular service, at the request of these States, 
 respectively, which have just been received at this De- 
 partment, are herewith transmitted for such disposition 
 as to the Legislature may seem proper. 
 
 PHILIP F. THOMAS. 
 
 * See A, B, C and D, hereto attached. 
 
RESOLUTIONS OF THE SENATE OF THE STATE OF 
 MARYLAND. 
 
 By the Senate, March dth, 1850. 
 
 Resolved hi/ the General Assemlli/ of Maryland, That 
 his Excellency the Governor be requested to cause to be 
 printed, The report and accomj)anying documents relat- 
 ing to the boundary line between this State and the 
 States of Pennsylvania and Delaware, communicated to 
 the Senate in his message of the 7th instant. 
 
 Resolved, That his Excellency the Governor be and is 
 hereby authorized to place temporarily in the custody 
 of Col. J. D. Graham, United States Topographical Engi- 
 neers, recently employed in retracing certain portions 
 of the conterminous boundaries of Maryland, Delaware 
 and Pennsylvania, the manuscript proceedings of the 
 commissioners and surveyors, including those of Mason 
 and Dixon, which relate to the demarcation of the 
 ancient boundaries between Maryland and Pennsylva- 
 nia, in conformity with the several agreements between 
 Cecilius Lord Baltimore and William Penn, and their 
 heirs and successors, together with said articles of 
 agreement, to enable the said Engineer to make such 
 reference to said documents as may be requisite to 
 illustrate his report on said boundaries to the Topo- 
 graphical Bureau. 
 
 Provided, the said document shall be returned to the 
 
archives of the State, on or before the first day of 
 January, 1861. 
 
 By order, 
 
 JOS. H. NICHOLSON, Chrh 
 
 By the House of Delegates, 
 
 March %th, 1850. 
 
 Read and assented to 
 
 By order, 
 
 G. G. BREWER, Cleric. 
 
 We hereby certify that the foregoing is a full and 
 true copy of Resolution No. 94, which was read and 
 assented to by the General Assembly of Maryland at its 
 December Session, 1849. 
 
 Given under our hands at the City of Annapolis, on 
 the 11th day of March, A D. 1850. 
 
 JOS. H. NICHOLSON, 
 
 Clerk of the Senate. 
 GEORGE G. BREWER, 
 
 Clerk of the House of Delegates^ Md. 
 
 MESSAGE FROM THE GOVERNOR OF PENNSYLVANIA. 
 
 To the Honorable the Senate and House of Representatives of the 
 Commomoealth of Pennsylvania : 
 
 Gentlemen : — The commissioner appointed in pursu- 
 ance of the fourteenth section of the act of the Legis- 
 lature of this State, of the tenth of April last, to act in 
 
conjunction with commissioners appointed, or to be 
 appointed, by the States of Delaware and Maryland, 
 with power to survey and determine the point of inter- 
 section of the States of Pennsylvania, Delaware and 
 Maryland, and to fix some suitable mark or monument 
 whereby the said point may hereafter be indicated, has 
 submitted to me his report, together with the joint 
 report of the commissioners to the several Executives 
 of those States, of their proceedings under their respec- 
 tive commissions, the report of the engineer employed 
 to conduct the survey, and a finished map constructed 
 therefrom. 
 
 In transmitting these documents to the Legislature, I 
 would particularly invite attention to important sugges- 
 tions in the report of the commissioner of this State. 
 That officer has, with much propriety, suggested the 
 importance of procuring from the State of Maryland, 
 — where they are fortunately preserved, — certified 
 copies of the official documents relating to the original 
 settlement of the boundaries between the provinces of 
 Pennsylvania and Maryland, not now to be found 
 among the archives of this State. He has also suggested 
 the propriety of the passage of an act, authorizing the 
 survey, defining and marking, with suitable monuments, 
 of that part of the circular line at present forming the 
 entire boundary between the two States of Pennsylva- 
 nia and Delaware, and ratifying the existing titles to, 
 and liens upon such lands heretofore supposed to be in 
 the State of Delaware, which may be found by the 
 running of said line, to be within the territory of this 
 
State ; and providing a limitation within which such 
 titles and liens may be transferred to the State of 
 Pennsylvania. 
 
 These suggestions are deemed worthy of, and are, 
 therefore, respectfully submitted to the attention and 
 consideration of the Legislature. 
 
 WM. F. JOHNSTON. 
 
 Executive Chamber, ") 
 
 Harrishurg, March 13, 1850. ) 
 
 REPORT OF THE COMMISSIONER OF PENNSYLVANIA. 
 
 Chestee, Pa., March 8, 1850. 
 To his Excellency, William F. Johnston, Governor of Pennsylvania : 
 
 The undersigned, commissioner appointed by your 
 Excellency, on the part of the State of Pennsylvania 
 under the fourteenth section of an act of the General 
 Assembly of this Commonwealth, passed the 10th day 
 of April, A. D. 1849, entitled "A supplement to an act, 
 entitled ^ An Act relative to the organization of courts 
 of justice,' passed the 14th day of April, A. D. 1834," 
 "to act in conjunction with commissioners appointed, or 
 to be appointed, by the States of Delaware and Mary- 
 land, with power to survey and determine the point of 
 intersection of the States of Pennsylvania, Delaware 
 and Maryland, and to fix some suitable mark or monu- 
 ment whereby the said point may hereafter be indi- 
 cated," has the honor to transmit herewith the annexed 
 
joint report of the commissioners, (marked A,) with 
 copies of the correspondence with Lieutenant Colonel 
 J. D. Graham, the Principal Engineer, under whose 
 charge the surveys were conducted ; (marked B, C and 
 D ;) and also, the accompanying elaborate report 
 (marked E) and certified map of Colonel Graham, ex- 
 hibiting full, and, I hope, satisfactory details of proceed- 
 ings and the result of the work. 
 
 The field work of the surveys, from the inclemency 
 of the weather and other unavoidable causes, as set 
 forth in the report of the Engineer, was prolonged, and 
 the expenses consequently increased much beyond 
 what were at first anticipated by the commissioners. 
 They have, however, the satisfaction of stating that the 
 work has been carefully done, and the scientific portion 
 of it prosecuted by a gentleman whose deservedly high 
 reputation in his profession, will give entire confidence 
 to its correctness, and important and difficult points on 
 the boundaries of the several States have been deter- 
 mined and permanently established ; from which the 
 line between Pennsylvania and Delaware, and the east 
 and west line between the former State and Maryland 
 can, without difficulty, at any future time, be run out, 
 determined and marked. 
 
 In searching for the official documents relating to the 
 original settlement of the boundaries between the 
 provinces of Pennsylvania and Maryland, none of any 
 importance could be found among the archives of this 
 State. They are all, however, fortunately preserved 
 among those of Maryland. I would, therefore, respect- 
 
fully suggest the importance of procuring certified 
 copies thereof, and having them printed for preserva- 
 tion, in connection with the present reports. 
 
 Permit me to remark, before closing this introductory 
 report, that in our intercourse with those citizens of the 
 States of Pennsylvania and Delaware, owning property 
 and residing contiguous to the boundary line of the two 
 States, and who are deeply and immediately interested 
 in having that line well defined, we found they were 
 under the impression the commissioners were authorized 
 — as it is believed it was intended by those originating 
 the commission they should be — to run out, define and 
 mark that part of the circular line at present forming 
 the entire boundary between the two States ; but our 
 authority not appearing to contemplate such a survey, 
 we could not feel ourselves warranted in gratifying 
 their expectations and wishes. 
 
 The necessity of defining and marking such circular 
 boundary line, is the more apparent from the fact, that 
 there does not appear to be any monuments or other 
 certain evidences of its true location, and there being 
 nothing but uncertain and conflicting traditionary 
 evidence of said line, great inconvenience has long 
 been felt and losses sustained, as well by the public in 
 the assessment and collection of taxes, as by individuals 
 owning land on or near the line ; since real estate in 
 the vicinity, sold under proceedings in partition or 
 execution for debt, will not bring its full value by 
 reason of the uncertainty of the titles derived from 
 courts, whose jurisdiction may not embrace such real 
 
10 
 
 estate. This uncertainty also produces difficulty in 
 borrowing and loaning monies upon the faith of lands, 
 when it is not known in which State to enter payments 
 or record mortgages to constitute a lien. I would, 
 therefore, respectfully suggest to your Excellency the 
 propriety of recommending the passage of an act 
 authorizing the surveying and marking said line, with 
 suitable monuments at convenient distances, to remedy 
 the existing evils. 
 
 All of which is respectfully submitted. 
 
 JOSHUA P. EYEE, 
 
 Commissioner on the part of Pennsylvania. 
 
 REPORT OF MR. BOWEN, FROM SELECT COMMITTEE, 
 TO THE LEGISLATURE OF PENNSYLVANIA. 
 
 Mr. Bowen, from the select committee to whom was 
 referred the message of the Governor, together with 
 the accompanying documents, in relation to the deter- 
 mination of the point of junction of the boundary lines 
 of the States of Pennsylvania, Delaware and Maryland, 
 by a joint commission from the said States, made the 
 following report : 
 
 That they have with much interest examined the 
 report of Joshua P. Eyre, Esq., the commissioner ap- 
 pointed by the State of Pennsylvania, the report of the 
 joint commission, and the very clear and elaborate re- 
 
11 
 
 port of Colonel J. D. Graham, of the United States 
 Topographical Engineers. 
 
 The importance of distinctly marking and commemo- 
 rating the limits of adjoining States, is forcibly illus- 
 trated in the present instance. The work of Messrs. 
 Mason and Dixon was the result of a protracted contro- 
 versy between the proprietors of adjoining provinces ; 
 was attended by every circumstance that should seem 
 to be necessary to give it notoriety and leave an indel- 
 ible impression upon traditionary memory ; was finished 
 by erecting permanent landmarks, of bold and striking 
 character, which, with two exceptions in the localities 
 examined, remain undisturbed : yet from the want of a 
 similar demarcation of the curved line beyond the point 
 of junction, and closely adjacent to the line thus exhib- 
 ited upon the surface of the ground, territory exceeding 
 a thousand acres, in the small space affected by these 
 lines, has been the subject of misapprehension and 
 doubt, which doubt has extended even to those portions 
 of boundary which it is now shown are well defined by 
 monuments, undisturbed since they were first estab- 
 lished. 
 
 The angle forming the north-eastern corner of Mary- 
 land, and the point of junction of the boundary lines 
 of the three States uniting in this commission, are now 
 settled. The curved line extending from this point of 
 junction to the river Delaware, has never been surveyed 
 and marked since the separation of the three lower 
 counties now forming the State of Delaware, from the 
 province of Pennsylvania. 
 
12 
 
 It is probably twenty-four or twenty-five miles in 
 extent, and its curvature renders it peculiarly difficult 
 to be ascertained for local and temporary purposes. 
 Your committee, therefore, recommend the appointment 
 of a commissioner to unite with a commissioner on the 
 part of the State of Delaware, should that State concur, 
 to ascertain and mark with precision this important 
 line. 
 
 In consequence of the misapprehension before noted, 
 and in view of the possible results of such survey, your 
 committee deem it a necessary precaution to provide for 
 the transfer of records and the final settlement of 
 pending controversies, should any exist, in relation to 
 lands that may be found to lie within other jurisdiction 
 than the parties in interest have supposed. Transac- 
 tions in good faith, founded upon such misapprehension, 
 are entitled to protection ; and though limited to a 
 narrow scope, much evil may possibly ensue, if due 
 provision be not made. Such provision should be 
 mutual between the adjoining States, and the passage 
 of reciprocal laws is therefore recommended in antici- 
 pation of the concurrence of the State of Delaware. 
 
13 
 
 (A) 
 
 REPORT OF THE JOINT COMMISSIONERS OF MARY- 
 LAND, PENNSYLVANIA AND DELAWARE. 
 
 City op Washington, March 1, 1850. 
 
 To their Excellencies P. Francis Thomas, Governor of Maryland, 
 William F. Johnston, Governor of Pennsylvania, and 
 William Tharp, Governor of Delaware : 
 
 The undersigned commissioners, appointed by your 
 Excellencies in pursuance of the legislation of our re- 
 spective States, for ascertaining and refixing certain 
 boundaries where the States of Maryland, Pennsylvania 
 and Delaware join each other, beg leave to make the 
 following report : 
 
 Early in October last, we individually and in joint 
 consultation, sought the information necessary to the 
 discharge of our duties, and after conference in the city 
 of Wilmington, saw that much science and many intri- 
 cate mathematical problems were involved, that not 
 only required the talents of men as commissioners dis- 
 tinguished in the annals of our country, and surveyors, 
 to carry out the agreement of the proprietary govern- 
 ments in 1760, but finally enlisted the services of those 
 distinguished mathematicians, Messrs. Mason and Dixon. 
 
 The work before us involved the important points 
 where the peninsular or tangent line intersects the due 
 north line, and where the curve, on a radius of twelve 
 English statute miles from New Castle, was required to 
 begin ; also, the intersection of said curve with the due 
 
14 
 
 north line, or the point where the three States join each 
 other, and the intersection of the north line with the 
 parallel of latitude — being the north-eastern corner of 
 Maryland, or boundary of Pennsylvania and Maryland 
 on the north. 
 
 Looking to the intricacy of the work and the distinc- 
 tion of our predecessors, the undersigned sought, through 
 your Excellencies, assistance from the General Govern- 
 ment. The Secretary of War promptly afforded it in 
 the detail of Lieut. Col. James D. Graham, of the corps 
 of Topographical Engineers, alike distinguished for the 
 corps to which he belongs, and the signal ability with 
 which he had executed many national works. 
 
 After a full inquiry into the subject, and studious 
 examination of the public archives at Annapolis, where 
 alone they were to be found in preservation, and copi- 
 ous extracts and notes from all connected with the agree- 
 ment of the proprietary governments of 1732 and 1760, 
 by Col. Graham, and the undersigned, we met Col. 
 Graham, again in New Castle, Wilmington and Newark, 
 Delaware, for observation, conference and reconnois- 
 sance ; when, for the purpose of a proper understanding 
 of our respective duties, the accompanying correspond- 
 ence, marked B, C, and D, was had. It resulted in an 
 experimental survey, under the direction of Col. Gra- 
 ham, with a full corps of assistant engineers, and such 
 men, for field labor, as were required by him and ap- 
 proved by the undersigned. 
 
 This experimental survey, the undersigned were grati- 
 fied to find, resulted most satisfactorily, so far as land- 
 
15 
 
 marks, remaining monuments, and supposed positions 
 for some of the lost monuments were involved ; and we 
 hoped that it might be final, and would close our labors; 
 but the computations and plotting developed great dis- 
 crepancies between our work, and that of the former 
 commissioners and Messrs. Mason and Dixon, both in 
 measurement and the true position of the tangent point. 
 
 The measurement, too, of the radius, or distance from 
 the centre of New Castle to the aforesaid tangent point, 
 involved consequences important to Maryland, Pennsyl- 
 vania and Delaware, as well as the correct running of 
 the curve, and determined us, on full consultation with 
 Col. Graham, to prosecute a system of triangulation that 
 would explain all discrepancies, afford accuracy to the 
 different measurements, and supply the true distance 
 from the steeple of the court house, at New Castle, to 
 the aforesaid tangent point, or to any part of the said 
 curve. 
 
 This work was entered upon and prosecuted with 
 great diligence, and would long since have been com- 
 pleted but for unsettled weather, which retarded the 
 field labor, interrupted instrumental observations, and 
 detained the engineers upon the line from the 15th day 
 of November to the 7th day of February. 
 
 On the 8th day of February, all the field hands were 
 discharged, and Col, Graham, with his assistants, repaired 
 to this place to complete their computations, and make 
 out such report and maps of the work as would afford 
 to all a correct view of the labor they had encountered. 
 
16 
 
 and the designation of an important portion of the terri- 
 torial limits of our respective States. 
 
 The undersigned, having determined to meet at this 
 place as soon as their presence was necessary to a final 
 adjustment of accounts and signing of maps, as well as 
 for an interchange of views as to their joint and several 
 reports, soon ascertained, that while their stay would 
 expedite the result, it would be marked with a delay 
 commensurate with all their early misconceptions of the 
 work. "We are, however, gratified with the belief that 
 constant and daily intercourse with Col. Graham, has 
 better enabled us to appreciate the continued extent of 
 labor, and precise scientific execution, that must ensure 
 the confidence of the scientific world, all of which will 
 be properly estimated by your Excellencies on examin- 
 ing the map and report of the Engineer, from which we 
 will not further withdraw your attention, and which are 
 submitted as the result of our commission. 
 
 We have the honor to be, 
 
 Respectfully yours, 
 
 H. G. S. KEY, 
 
 Commissioner on the part of Maryland. 
 
 JOSHUA P. EYRE, 
 
 Commissioner on the part of Pennsylvania. 
 
 GEO. READ RIDDLE, 
 
 Commissioner on the part of Delaware. 
 
17 
 
 (B) 
 
 THE JOINT COMMISSIONERS TO LIEUT. COLONEL 
 
 GEAHAM. 
 
 Wilmington, Delaware, November 12, 1849. 
 
 To Lt. Col. J. D. Graham, 
 
 Of the U. S. Topographical Engineers : 
 
 Sm : The tindersigned, commissioners on the part of 
 the States of Maryland, Pennsylvania, and Delaware, 
 appointed for the ascertainment of the boundary, or 
 point of intersection where the three States join each 
 other, and such other boundaries of the said States as 
 are necessary to accuracy in refixing and establishing 
 the same, are ready, under your assistance, to proceed 
 with the work ; and, looking to your experience for the 
 mode or instructions by which the field operations are to 
 be conducted, ask you to furnish a detailed plan thereof 
 for the approval of the board, and the accomplishment 
 of the purposes of our respective States. 
 
 Permit us further to add, that, if found necessarj^ to 
 accuracy in ascertaining the above point, it is our pur- 
 pose to refix such stones as may be broken or lost with 
 new stones or monuments, particularly at the following 
 points, viz. : 
 
 1st. The beginning of the curve or north end of the 
 tangent line. 
 
 2d. The meridian of the curve between Delaware 
 and Maryland. 
 
 od. The point or place of intersection of the due 
 2 
 
18 
 
 north line and the said curve, being the point of inter- 
 section of the three States 5 and 
 
 4th. The north end of the aforesaid due north line, 
 or intersection of said line with the east and west line 
 of Mason and Dixon, being " a parallel of latitude fifteen 
 English statute miles south of the most southern part of 
 the city of Philadelphia," and the boundary of Pennsyl- 
 vania [on the south], and Maryland on the north. 
 Respectfully, 
 
 H. G. S. KEY, 
 
 Commissioner on the part of Maryland. 
 
 JOSHUA P. EYRE, 
 
 Commissioner on the part of Pennsylvania. 
 
 GEO. READ RIDDLE, 
 
 Commissioner on the part of Delaware. 
 
 LIEUT. COL. GRAHAM TO THE JOINT COMMISSIONERS. 
 
 Newark, Delawaee, November 15, 1849. 
 
 Gentlemen: I have the honor to acknowledge the 
 receipt, on the 12th inst., of your joint communication 
 of that date, requesting me to present, for the approval 
 of your board, a detailed plan of operations for the ascer- 
 tainment of the boundary or point where the States of 
 Maryland, Pennsylvania, and Delaware join each other, 
 and such other boundaries of the said States as are 
 
19 
 
 necessary to accuracy in refixing and establishing the 
 same. Having, in company with your board, made an 
 examination of a portion of the boundaries extending 
 from the north-east corner of Maryland, two or three 
 miles south of the tangent point, or point of contact of 
 the peninsular line with the periphery of the circle of 
 twelve miles radius from the centre of New Castle, I now 
 respectfully submit to you the following suggestions : 
 
 It appears that the junction of the boundaries of the 
 three States, is at the northern intersection of the 
 abovenamed circle, with the meridian line running due 
 south from the north-east corner of Maryland, and that 
 the said meridian line again intersects the circle at a 
 point one mile and seven hundred and ninety-three 
 yards and three-tenths of a foot due south of the pre- 
 ceding point. This last-mentioned point is the tangent 
 point, or point of contact of the peninsular line with 
 the said circle. 
 
 If this tangent point can be identified with certainty 
 upon the ground, having the direction of the tangent 
 line well marked by monuments already found, the por- 
 tion of the circle in question can, very readily, be traced 
 and continued, until its cord shall coincide with the me- 
 ridian line already named, which will give the point 
 required. 
 
 If the stone which was originally placed to mark the 
 tangent point is missing, it will be desirable to find that 
 point, and replace the stone monument upon it, as a 
 point of beginning to trace the curve. This may be 
 done by prolonging the direction of the tangent line, 
 
20 
 
 deduced from any two monuments found upon it, until 
 the direction of the line perpendicular to it shall pass 
 through the centre of the circle of twelve miles radius, 
 which is understood to be the steeple of the court house 
 at New Castle ; or this tangent point, and also the point 
 of junction of the three States, may be fixed by pro- 
 longing, trigonometrically, the true meridian direction 
 from the north-east corner of Maryland due south, until 
 the required distances, obtained from the original sur- 
 veys of Mason and Dixon, of three miles and nine hun- 
 dred and ninety-nine and nine-tenths yards, and five 
 miles and thirty-three yards from the said north-east 
 corner of Maryland, shall be reached. 
 
 The meridian direction must, in that case, be obtained 
 by astronomical observations with a transit instrument 
 and good chronometers, and the triangulation be exe- 
 cuted with a good theodolite, adapted to nice geodetic 
 operations, all of which I already have at my command. 
 
 But the first step in the operation I conceive to be, 
 to cause a rapid experimental survey to be made with 
 the chain and small transit theodolite, that shall lay 
 down all the monuments now existing, from some point 
 one or two miles south of the tangent point, to the 
 north-east corner of Maryland. When this survey is 
 plotted, we shall be enabled to show all the monuments 
 now existing on the ground, and, by comparing their 
 distances apart, with those given in the notes of survey 
 of Messrs. Mason and Dixon, to ascertain what monu- 
 ments, if any, are missing; and then we shall be enabled 
 to ascertain likewise, with precision, according to the 
 
21 
 
 most applicable of the methods above suggested, the 
 points they should occupy, and hence proceed to erect 
 them under your immediate supervision. 
 
 If it meet your approbation, we will proceed' at once 
 with the preliminary survey. 
 
 I remain, gentlemen, 
 
 Very respectfully. 
 
 Your obedient servant, 
 
 J. D. GRAHAM, 
 
 Lt. Gol. Topographical Engineers. 
 
 To Messrs. H. Gr. S. Key, Joshua P. Eyee, and Geo. Read Riddle, 
 Commissioners, &e., &c., &c. 
 
 (I>) 
 
 THE JOINT COMMISSIONERS TO LIEUT. COLONEL 
 
 GRAHAM. 
 
 Newark, Delaware, Novemher 15, 1849. 
 
 To. Lt. Col. J. D. Graham, 
 
 United States Topographical Corps of Engineers : 
 
 Sm: We have duly received and considered your 
 communication of this day, in reply to ours of the 
 twelfth instant, dated at Wilmington, and take pleasure 
 in saying, that we concur in your views and plans for 
 the operations necessary to the purposes of our respec- 
 tive States. 
 
22 
 
 The extent of work intimated in your communica- 
 tion, is about what we presumed was indispensable to 
 accuracy, from our early examination of the archives 
 of our States, connected with the operations of Messrs. 
 Mason and Dixon, and the observations we had made 
 on a previous examination of much of the lines that 
 might be the field of our labors ; and that the main 
 points may be so marked with a view to future perma- 
 nency, we propose to mark with stones or monuments 
 as follows : 
 
 1. The tangent point, or north end of the tangent 
 line, shall be marked with the letters TANGENT, and 
 with the letter M on the side next to the State of Mary- 
 land, and the letter D on the side next to the State of 
 Delaware. 
 
 2. The meridian of the curve shall be marked, on 
 the side next to the State of Maryland, with the letter 
 M, and shall be oval on that side ; and shall be marked 
 on the side next to the State of Delaware, with the 
 letter D. 
 
 3. The point or place of intersection of the due north 
 line and the curve — being the point of intersection of 
 the three States — shall be marked with a stone of tri- 
 angular shape, and the letters M, P, and D, on the sides 
 towards the respective States of Maryland, Pennsylvania, 
 and Delaware, and also with the names of the commis- 
 sioners on some side thereof 
 
 4. The north end of the aforesaid due north line, or 
 intersection of said line with the east and west line of 
 
23 
 
 Mason and Dixon, being the boundary of Pennsylvania 
 [on the south], and Maryland on the north, shall be 
 marked as follows : On the sides next to the State of 
 Maryland with the letter M, and on the sides next to 
 the State of Pennsylvania with the letter P. 
 
 We also propose, that all the said stones, or monu- 
 ments, shall have 1849 inscribed on some side thereof, 
 and be fixed at least four feet deep in the ground, and 
 shall show at least thirty inches above the ground. 
 
 We beg leave further, most respectfully to suggest, 
 that the progress of your operations may present modi- 
 fications, which will be considered, by you and ourselves, 
 with due regard to the objects to be attained. 
 
 We have the honor to be. 
 
 Respectfully yours, &c., 
 H. G. S. KEY, 
 
 Commissioner on the part of Maryland. 
 
 JOSHUA P. EYRE, 
 
 Commissioner on the part of Pennsylvania. 
 
 GEO. READ RIDDLE, 
 
 Commissioner on the part of Delaware. 
 
25 
 
 (E) 
 COL. GRAHAM'S REPORT TO THE COMMISSIONERS. 
 
 Washington, February 27, 1850. 
 
 To Messrs. H. G-. S. Key, Joshua P. Eyre and Geokge Read Riddle, 
 Commissioners for adjusting and refixing certain parts of the bound- 
 aries of the States of Maryland, Pennsylvania, and Delaware : — 
 
 Gentlemen : Having been invited by you, in Novem- 
 ber last, to conduct the surveys and examinations neces- 
 sary to the elucidation and adjustment of certain 
 portions of the conterminous boundaries of your re- 
 spective States, known as " Mason and Dixon's line," for 
 which purpose you were appointed commissioners by 
 the Governors of those States, under authority of recent 
 legislative enactments, I have the honor now, in pursu- 
 ance of a conference with you upon the subject, to lay 
 before you a report, showing all that has been done in 
 the field, and which will serve to show, and enable you 
 to decide, what more ought to be done, by authority 
 of further legislation, to complete the demarcation of 
 the boundaries of two of these conterminous States; 
 namely, Pennsylvania and Delaware. 
 
 As soon as the maps showing the surveys we have 
 already made, can be completed, which I understand 
 you wish to lay before your respective State authorities 
 with as little delay as possible, I propose to make a 
 
26 
 
 more full report, embracing such notices as will present 
 a general view of the scientific operations of Messrs. 
 Mason and Dixon, and of their predecessors, in tracing 
 the various lines which now constitute important por- 
 tions of the boundaries of those States. This report 
 will be duly communicated to you when completed. 
 
 In pursuance of authority from the Bureau of Topo- 
 graphical Engineers, I repaired, on the 30th of October 
 last, to Annapolis, to confer with the Governor of Mary- 
 land, in reference to the duty which relates to the 
 verification of certain points in the boundary between 
 the States of Maryland, Delaware, and Pennsylvania, 
 and to investigate the notes of Mason and Dixon, which 
 were understood to be in the archives of the State of 
 Maryland. 
 
 These documents, together with the articles of agree- 
 ment between Charles Lord Baltimore, and the heirs 
 and successors of William Penn, of the 10th day of 
 May, 1732, and of the subsequent agreement between 
 Frederick Lord Baltimore, and Thomas and Richard 
 Penn, the surviving heirs of William Penn, entered into 
 the 4th of July, 1760, and also the records of the pro- 
 ceedings of their commissioners and surveyors, from 
 time to time duly appointed, all in manuscript, were 
 placed at my disposal by his Excellency, Philip F. 
 Thomas, Governor of Maryland. These manuscripts 
 embrace a period of near thirty-seven years ; namely, 
 from May 10th, 1732, to the end of the year 1768. 
 From them such extracts and brief minutes were made 
 
27 
 
 as were deemed requisite to a proper understanding of 
 the lines to be examined. 
 
 The articles of agreement finally entered into between 
 the parties, and their instructions to their commission- 
 ers, define clearly the lines of boundary between the 
 then provinces of Maryland and Pennsylvania, in con- 
 formity to the memorable decree of Lord Chancellor 
 Hardwicke, pronounced the 15th of May, 1750, which 
 set at rest for a time, and was the basis of the final 
 settlement of a dispute that had lasted many years, 
 between the proprietaries, as well as the border inhab- 
 itants, of these two provinces. 
 
 Without quoting these articles at length, it will be 
 sufficient here to state that, the boundary between the 
 two provinces was thus required to be run, namely : to 
 begin at Cape Henlopen, and run a line due west to a 
 point midway between that Cape and the shore of 
 Chesapeake Bay. 
 
 From this middle point a line was to be run northerly 
 in such direction, that it should be tangent to a circle 
 whose centre was decided to be the centre of the court 
 house* at New Castle, and whose radius should be twelve 
 English statute miles, measured horizontally. From the 
 tangent point of contact of the northerly line with the 
 
 * See the old parchment containing the agreement of May, 1760, and the 
 
 instructions from the commissioners to the surveyors, given at New Castle, the 
 
 7th of November, 1761, contained in the proceedings of the commissioners, in 
 
 manuscript, at Annapolis. They specify the exact point for the centre of the 
 
 circle, as well as the length of, and the manner of tracing out the radius. 
 
 J. D. G. 
 
28 
 
 periphery of the ch^le, the line was to be continued 
 due north until it should reach a point fifteen English 
 statute miles, measured horizontally, south of the par- 
 allel of latitude of the most southern point of the city 
 of Philadelphia * 
 
 * The following is an extract from the proceedings of the commissioners, con- 
 vened at Philadelphia, under date of December 3, 1763 : 
 " The commissioners met according to adjournment. 
 
 "Present as yesterday, and also Benjamin Chew, Esq., another of the commis- 
 sioners for Pennsylvania. 
 
 " The commissioners having, in consequence of their agreement of yesterday, 
 requested the Mayor and Eecorder, and some of the persons appointed to lay out 
 lots and regulate water courses in the streets of the said city, which office requires 
 that they should be men well acquainted with the exact situation of the several 
 streets, and the dimensions of the several squares and lots of ground therein, to 
 show them which is the most southern part thereof. The said Mayor and Recorder, 
 and two of the said regulators, to wit : Alderman Ehoades and Mr. Jacob Lewis, 
 went with the commissioners and Messrs. Mason and Dixon, to the street called 
 Cedar, or South street, the south side of which street the said Mayor, Recorder, 
 and Regulators informed the commissioners is, and, as they verily believe, ever has 
 been, ft-om the time the said city was first laid out, deemed and taken to be the 
 southern boundary and limit thereof, and to which boundary the Mayor, Recorder, 
 and Aldermen of the said city have constantly exercised jurisdiction ; by which 
 information, and a view of some old deeds that were produced by persons possessed 
 of lots bounding on the said Cedar street, and of a plat of the said city, the com- 
 missioners were all satisfied that the north wall of a house, at this time occupied 
 by Thomas Plumsted and Joseph Huddle, is the most southern part of said city of 
 Philadelphia. The commissioners then adjourned to Monday morning, at ten 
 o'clock. 
 
 J. RID OUT, JAMES HAMILTON, 
 
 JNO. LEEDS, RICHARD PETERS, 
 
 JOHN BARCLAY, BENJAMIN CHEW, 
 
 GEO. STEUART, WM. COLEMAN, 
 
 DAN. OF ST. TIIOS. JENIFER, JNO. EWING." 
 
 Note 2. — The latitude of the north wall of this house, occupied in 1763 by 
 Thomas Plumsted and Joseph Huddle, was determined by Messrs. Mason and 
 Dixon, from astronomical observations, in 1763-64, with a zenith sector, to be 
 
29 
 
 From the northern extremity of the said due north 
 line, a line was to be run due west, continuing upon a 
 parallel of latitude until the western limits of Maryland 
 and Pennsylvania should respectively be reached, which, 
 in the case of Pennsylvania, was defined to be five de- 
 grees of longitude west of the river Delaware. 
 
 The conclusion of the eighth article of the agreement 
 of 1732, which is incorporated into the instructions of 
 Lord Baltimore, and John, Thomas, and Richard Penn, 
 to their respective commissioners, dated the 12th of 
 May, 1732, and repeated in all the sulfeequent instruc- 
 tions, provides that " in case said north line from the 
 tangent of the circle of New Castle, shall break in upon 
 the said circle, in such case, so much of the said circle 
 as shall be cut off by the said line, shall belong to, and 
 be part of the county of New Castle."* 
 
 In pursuance of the decree of 1750, commissio|iers 
 and surveyors were appointed to run the required lines. 
 In 1751, a line was traced due west from Cape Henlo- 
 pen to the shore of Chesapeake Bay, and its length 
 ascertained, by measuring with a chain, to be sixty-nine 
 miles and two hundred and ninety-eight perches. At 
 the distance of sixty-six miles and twenty-four and one- 
 
 39'^ 56' 29" .1. The point, fifteen English statute miles due south of that parallel, 
 was computed by Messrs. Mason and Dixon, to be in latitude 39° 43' 18". From 
 our knowledge of the dimensions and figure of the earth, wc should at this day 
 compute it to be in latitude 39*^ 43' 26" .3. J. D. G. 
 
 * It seems to have been doubtful, when these articles were drawn, whether the 
 direction of the tangent line would be north-westerly or north-easterly from the 
 middle point of the west line run from Cape Henlopen to the shore of the 
 Chesapeake Bay. J. D. G. 
 
30 
 
 half perches from the point of beginning, Slaughter's 
 Creek was reached, and here Lord Baltimore's com- 
 missioners contended the line should end ; but those on 
 the part of the Penns insisted that it should be ex- 
 tended to the eastern verge of the bay. 
 
 In April, 1751, Charles Lord Baltimore died, and the 
 demarcation of the boundary was suspended. His heir 
 and successor, Frederick Lord Baltimore, raised objec- 
 tions to the decree of 1750, and determined to resist its 
 execution, which brought on a new controversy between 
 the proprietaries. Before a decree was had upon it, an 
 agreement was entered into between the parties on the 
 4th of July, 1760, which, in fact, adopted the points 
 that had been previously settled by the agreement of 
 May 10th, 1732, and the decree of May, 1750, as to the 
 lines defining the boundaries. The proceedings of the 
 former commissioners were also recognized by this 
 agreement, and confirmed by it so far as they were con- 
 clusive. Cape Henlopen was determined to be the 
 point previously fixed upon as marking this cape, and 
 the termination of the due west line from thence across 
 the peninsula, was decided to be that which had been 
 contended for by the commissioners of Pennsylvania ; 
 and the middle point of that line, from whence the tan- 
 gent line was to start, was decided to be thirty-four 
 miles and three hundred and nine perches from the 
 point of beginning at Cape Henlopen. 
 
 At the middle point of this peninsular line, a bound- 
 ary stone was to be planted at their joint expense, 
 marked on the south and west with the arms of Lord 
 
31 
 
 Baltimore, and on the north and east with the arms of 
 the Penn family, graven thereon. 
 
 Commissioners were required to be appointed by 
 each of the parties within thirty days after the execu- 
 tion of this agreement, to carry its provisions into effect. 
 This was accordingly done, and the said commissioners 
 met at New Castle, the 19th of November, 1760, and 
 immediately entered upon the discharge of the duties 
 committed to them. 
 
 The lines, as they were traced and approved by the 
 commissioners, were marked and defined by posts of 
 cut stone, about four feet long, and ten to twelve inches 
 square, placed at the distance of one mile apart. These 
 stones were prepared in England, and sent over to 
 America from time to time, as the lines progressed. 
 Every fifth mile stone was engraved with the arms of 
 Lord Baltimore on the side facing towards Maryland, 
 and with the arms of the Penn family on the side facing 
 towards Pennsylvania. 
 
 The agreement of 1732 stipulated, and it was ordered 
 in the decree by the Lord High Chancellor, that the 
 bounds should be marked with the arms of the proprie- 
 taries on the sides facing towards their respective ter- 
 ritories. 
 
 The other mile stones were engraved with the letter 
 M on the sides facing Maryland, and with the letter P 
 on the sides facing Pennsylvania. 
 
 From November, 1760, to the latter part of October, 
 1763, the commissioners and surveyors were laboring 
 in attempts to trace out the radius of twelve miles, and 
 
32 
 
 the tangent line from the middle point of the west line 
 across the peninsula. The measurements were all made 
 with a chain of sixty-six feet, divided into one hundred 
 links, except alone that a triangulation was extended a 
 short distance from the court house at New Castle, in 
 running out the radius, in order that the true point of 
 departure should be the steeple or centre of that build- 
 ing, which could not be reached with the chain. The 
 surveyors were required to compare their chains with a 
 standard measure as often as might be necessary, to re- 
 duce "the chaining to accurate measure. 
 
 Several experiments were made to approximate to a 
 proper junction of the radius of twelve miles, with a 
 true tangent line, from the middle post. In this pro- 
 tracted, tedious, and expensive operation, vistas were 
 required to be opened along all the lines traced through 
 the dense forest that then overspread the country. 
 
 The rectilinear directions were attempted to be pre- 
 served by setting up poles or staves in line, as the work 
 progressed. 
 
 As late as the 21st of October, 1763, no practical so- 
 lution of this problem had been effected, although, as 
 was afterwards ascertained, a close approximation to the 
 true tangent point had been reached. 
 
 A post marked ^^i ^^^ been planted at the extremity 
 of a line traced for a radius, west from the court 
 
 house at New Castle ; and two other posts, one marked 
 
 T 
 ^jj and the other marked TP, had been planted at the 
 
 northern extremities of lines traced for a tangent. Each 
 
33 
 
 of these three posts was supposed, when planted, to ap- 
 proximate very near to the true tangent point. 
 
 In the proceedings of the commissioners, under date 
 of October 22, 1768, we find the following minute, 
 viz. : — 
 
 " The commissioners having taken into consideration 
 the agreement entered into by them at their last meet- 
 ing, to represent to their respective constituents what 
 lines had been already run, after what manner, and 
 what had been the issue, in order that they might give 
 the necessary directions for running and ascertaining the 
 tangent line, the Pennsylvania commissioners informed 
 the Maryland commissioners that they had lately re- 
 ceived a letter from the proprietors of Pennsylvania, 
 dated the 10th of August last, acquainting them that 
 they and Lord Baltimore had agreed with two mathe- 
 maticians, or surveyors, to come over and assist in run- 
 ning .the lines agreed on in the original articles, who 
 were to embark for Philadelphia the latter end of 
 August last, and that their arrival might soon be ex- 
 pected. Whereupon, the commissioners were of opin- 
 ion that it was better to delay making the representation 
 to their constituents, according to their former proposal, 
 imtil the arrival of the said mathematicians. 
 
 " The commissioners then adjourned to the 30th of 
 November next, to meet at the city of Philadelphia ; 
 but agreed that if the mathematicians should arrive 
 long before the 30tli of November, the meeting should 
 be on such other earlier day as the respective Governors, 
 by letter should agree on, and at any other place than 
 3 
 
34 
 
 the city of Philadelphia, if it should be more convenient 
 for the entering upon their work." 
 
 Under date of December 1st, 1763, at a meeting of 
 the commissioners, it is noted that the articles of agree- 
 ment were read between Lord Baltimore and Thomas 
 and Richard Penn, and Charles Mason and Jeremiah 
 Dixon, bearing date the 4th day of August last, directed 
 to their commissioners ; " also, a commission to the said 
 commissioners, recommending it to them to take to their 
 aid and assistance the said Charles Mason and Jeremiah 
 Dixon, and employ them to mark, run out, settle, fix, 
 and determine all such parts of the circle, marks, lines, 
 and boundaries as are mentioned in the several articles 
 of agreement or commissions, and are not yet com- 
 pleted. Likewise a paper of hints given by Dr. Bevis 
 and Mr. Harris to Lord Baltimore and Thomas and 
 Richard Penn, referred and recommended to the con- 
 sideration of their respective commissioners, and then 
 adjourned to to-morrow," &c. &c. 
 
 Thus we are introduced to Messrs. Mason and Dixon, 
 who superseded the former survej^ors in the employment 
 of marking out these boundary lines. They imme- 
 diately entered upon their duties, and were employed 
 in tracing and marking the several lines already de- 
 scribed* until the 26th of December, 1767, when they 
 were honorably discharged. Of the work of their pre- 
 
 * The line west from the north extremity of the due north line was not pro- 
 longed as far as five degrees of longitude from the Delaware by Mason and Dixon. 
 On reaching a point two hundred and thirty miles, eighteen chains and twenty- 
 one links west of the extremity of the due north line, their further progress was 
 aiTested by the Indians. J- D. G. 
 
35 
 
 decessors, the running of the clue west line from Cape 
 Henlopen to its termination midway between said cape 
 .and the shore of Chesapeake Bay, the trace and meas- 
 urement of the radius of twelve miles from New Castle 
 court house, and the determination of the tangent point 
 in the circle, only were accepted as settled. The lines 
 traced by their predecessors in their attempts to run 
 the tangent line, a line of eighty-two miles nearly in 
 length, were, however, of great aid to Messrs. Mason 
 and Dixon in finally establishing that line. In tracing 
 it, by aid of the transit instrument, through a vista 
 which they had opened in 1764, which was assumed by 
 calculation to be the true tangent line, Messrs. Mason 
 and Dixon constantly note how far, at every five mile 
 post, their line passed from the posts previously set by 
 their predecessors. 
 
 In their minutes of survey they say : ^''November l^th, 
 1764. Produced the line to the point shown us (in the 
 direction of the radius of twelve miles from New Castle, 
 mentioned in the minutes of the 25th and 27th of 
 August), to be the tangent point settled by the former 
 surveyors, and measured the distance of our line from 
 the said point, and found it was sixteen feet seven 
 inches to the eastward of the said point. 
 
 " We continued our line fifty-two and a half yards, and 
 
 m 
 
 then it was opposite the post marked -^jj and found we 
 vrere sixteen feet from the said post eastward. 
 
 " We also continued the line forty-one and a half 
 yards farther, and then we were opposite the post 
 
36 
 
 marked T P, and then we measured the distance of our 
 line from the said post, and found it was fifteen feet 
 two and a half inches to the eastward. 
 
 " November 12. Sent two expresses, viz. : one to his 
 Excellency Horatio Sharpe, Esq., Governor of Mary- 
 land, and the other to the Hon. James Hamilton, Esq., 
 to acquaint them we finished our second line on Satur- 
 day last. 
 
 " November 13. From the data in the minute of the 
 27th of August we computed how far the true tangent 
 line would be distant from the post shown us to be the 
 tangent point, and found it would not pass one inch to 
 the westward or the eastward. 
 
 " On measuring the angle formed by our last line and 
 the radius from New Castle, it was so near a right angle 
 that, on a mean from our lines, the above-mentioned 
 post is the true tangent point. 
 
 " From the whole we conclude that the ofl^set posts 
 in our second line, marked M D, are (as near as practi- 
 cable) in the true tangent line. 
 
 CHARLES MASON, 
 JEREMIAH DIXON." 
 
 From the record of proceedings of the commissioners, 
 the following is an extract : 
 
 " Saturday, Jsfovemher 2ifh, 1764. 
 " The commissioners met according to adjournment. 
 " Present as yesterday [namely : Horo. Sharpe, John 
 Leeds, John Barclay, Dan. of St. Thomas Jenifer ; Ben- 
 
37 
 
 jamin Chew, John Ewing, Edward Shippen, Jr., and 
 Thomas Willing]. 
 
 " The commissioners, having resumed the considera- 
 tions of yesterday, 
 
 " Agreed, That the post set up by Messrs. Mason and 
 Dixon, and by them marked West, shall be and be 
 deemed and accounted fifteen miles south of the parallel 
 of the most southern bounds of the city of Philadelphia, 
 and that Messrs. Mason and Dixon shall be instructed 
 immediately to proceed in running the west line di- 
 rected by the articles from the said post till it reaches 
 the river Susquehannah, where an observation shall be 
 made by them. 
 
 " Agreed., also, That the post set up in the extremity 
 of the radius of twelve miles from New Castle, marked 
 -j^jj shall be and be deemed and accounted to be the 
 true tangent point, and that the surveyors shall proceed 
 to run the north line, and such part of the circle as falls 
 to the westward of the said line, according to the arti- 
 cles, from the said point, as soon as they have run the 
 said west line to the river Susquehannah. 
 
 " Agreed, also, That the posts set up by Messrs. Mason 
 and Dixon at the eastern extremities of the offsets made 
 from the line they first run from the point marked 
 Middle, and by them marked M D, shall be and be 
 deemed and accounted to stand in the direction of, and 
 to mark and describe the tangent line. 
 
 " Agreed, lastly, That as soon as the surveyors shall 
 have run the said west line to the river Susquehannah, 
 and the said north line and part of the circle, stones 
 
38 
 
 shall be set up marked with the arms of the Lord Balti- 
 more on one side, and the arms of the proprietors of 
 Pennsylvania on the other, as the articles require and 
 direct, along the said tangent line, in the places where 
 the offset posts stand therein, at the tangent point marked 
 ■j^jj in several points of the periphery of the circle, in 
 the north line, at the point where the said north line 
 shall intersect the said west line, and along the said west 
 line to the river Susquehannah, to be and remain as 
 marks and boundaries forever, between the said province 
 of Maryland and the counties of New Castle, Kent, and 
 Sussex, on Delaware, and between the said province of 
 Maryland and the province of Pennsylvania, as far as 
 the river Susquehannah." 
 
 The commissioners then agreed to give instructions 
 pursuant to the foregoing agreement, and did so ; and 
 then adjourned over to the 16th of June next, then to 
 meet at Christiana Bridge. 
 
 '&' 
 
 " Christiana Bridge, June 16, 1765. 
 
 " The commissioners met according to their adjourn- 
 ment of November 24th last," &c., &c. 
 
 Commissions were read from the proprietors, prolong- 
 ins: the time for running; the lines to the 31st December, 
 1765, &c. &c. 
 
 " Adjourned to to-morrow morning, ten o'clock." 
 
 " Christiana Bridge, June 17, 1765. 
 " The commissioners met," &c. &c. 
 " The surveyors produced to the commissioners their 
 
39 
 
 minute books, which being compared, examined and 
 found to agree, it appears thereby that in pursuance of 
 the instructions given them the 24th day of November 
 last, they have extended the west line to the west side 
 of the river Susquehannah, run a north line from the 
 tangent point to intersect the said west line, and also 
 described such part of the circle round New Castle as 
 falls westward of said north line. 
 
 " The commissioners approving of the lines run by 
 the said surveyors, agreed to have a stone (the only one 
 they have at present, on which are graven the arms of 
 the respective proprietors), immediately fixed at the 
 said tangent point ; another stone at the point where 
 the above mentioned west line and north line intersect 
 each other ; one other stone in the said north line, with- 
 out the periphery of the circle ; one at the point where 
 the north line and circle intersect ; and three others at 
 different places in the said circle. The six last-mention- 
 ed stones to remain only until others more proper for 
 the purpose, and with the arms of the right honorable 
 the Lord Baltimore, and the honorable proprietors of 
 Pennsylvania, graven thereon, can be procured. 
 
 " And then adjourned to to-morrow morning." 
 
 "Newark, June 18, 1765. 
 " The commissioners met according to adjournment. 
 Present as yesterday; and went and fixed a stone, 
 marked with the arms of the lord proprietary of Mary- 
 land on the west, and the arms of the proprietors of 
 Pennsylvania on the east side of it, in the tangent point; 
 
40 
 
 and also set up stones at the other places, accordmg to 
 their agreement of yesterday;" after which they gave 
 Messrs. Mason and Dixon instructions to proceed with 
 the running of the west line westward of the Susque- 
 hannah, as far as the provinces of Maryland and Penn- 
 sylvania are settled and inhabited, unless obliged to 
 desist on account of severe weather, or they should 
 before that time receive instructions to desist from their 
 work. 
 
 " The commissioners then adjourned to meet," &c. &c. 
 
 " Thuksday, November '20, 1766. 
 
 " The commissioners met," &c. &c. 
 
 " Present as yesterday, [namely : John Barclay, Dan. 
 of St. Thomas Jenifer, J. Beale Bordley, William Allen, 
 Benjamin Chew, John Ewing and Thomas Willing.] 
 
 sj: ♦ H: ^ :5j :?: Hi 
 
 " Messrs. Ewing and Barclay report to the other com- 
 missioners, that in pursuance of their agreement, by 
 their letters of the 5th and 22d of October last, thirty- 
 one stones have been set up at a mile's distance each, 
 in the tangent line (in the places where posts had been 
 fixed in the said line by Messrs. Mason and Dixon), 
 from the fiftieth mile stone, set up formerly, to the 
 tangent point ; each five mile stone being marked with 
 the arms of the right honorable Lord Baltimore on the 
 west side, and the arms of the honorable ^proprietors of 
 Pennsylvania on the east, and the other intermediate 
 stones, with the letter M on the west side and the letter 
 P on the east. And the better to distinguish and ascer- 
 
41 
 
 tain the tangent point, anotlier stone, marked with the 
 arms of Lord Baltimore on the west side, and of the 
 ^proprietaries of Pennsylvania on the east, hath been 
 set up at the south side of the stone fixed in the said 
 tangent point, by the commissioners on the 18th of 
 June, 1765. 
 
 " That one stone marked with the letter M on the 
 west side, and the letter P on the east, hath been set 
 up in the arc of the circle ; and three stones marked as 
 the latter, have been set up in the north line from the 
 tangent point, in the places where Messrs. Mason and 
 Dixon had set up mile posts in those lines. 
 
 " That sixty-four stones have been set up in the west 
 line, the first of which stands at the distance of one 
 mile to the westvv^ard of the stone fixed by the com- 
 missioners, on the 18th of June, 1765, in the point 
 where the west and north lines intersect, and the others 
 at the same distance from each other, except at the end 
 of sixty-four miles, where a proper stone was wanting, 
 and is to be fixed at a future time, each five mile stone 
 having the arms of the Lord Baltimore graved thereon, 
 on the south side, and the arms of the proprietors of 
 Pennsylvania on the north, and the intermediate stones 
 marked with the letter M on the south, and with the 
 letter P on the north side." 
 
 The rest of the proceedings of this meeting relate to 
 the completion of the west line, and to obtaining the 
 consent of the Indians to its being continued, &c. &c. 
 Then the commissioners adjourned to meet at Chester- 
 town, Maryland, on the 19th of March, 1767, or such 
 
42 
 
 earlier or later day as the commissioners ma}^ by letter 
 agree on. Their next meeting did not, however, for 
 reasons stated, take place until the 16th day of June, 
 1767. On that day the commissioners met. Sir Wil- 
 liam Johnson, his Majesty's agent for Indian affairs, had 
 obtained the consent of the Indians to the tracing of 
 the west line to its western extremity, that is to say, till 
 it should reach to a distance of five degrees of longi- 
 tude west from the river Delaware. 
 
 On the 18 th of June, 1767, the commissioners met, 
 and gave to the surveyors their instructions for continu- 
 ing the trace of the west line to five degrees of longi- 
 tude west from the river Delaware, in the parallel of 
 the said west line, and cautioning them in regard to a 
 conciliatory and proper conduct towards the Indians. 
 
 " Friday, December 25, 1767. 
 
 " The commissioners met according to adjournment," 
 &c. &c. 
 
 " The surveyor's books were read, compared, and 
 found to agree, by which it appears that they have ex- 
 tended the parallel of latitude, agreeable to the in- 
 structions given them by the commissioners on the IStli 
 day of June last, to the distance of two hundred and 
 thirty miles, eighteen chains, twenty-one links from the 
 beginning of said line, and two hundred and forty-four 
 miles thirty-eight chains, thirty-six links from the river 
 Delaware, near to a path called the Indian war path, 
 but that they were prevented by the Indians deputed 
 to attend them, by Sir William John-son, from continu- 
 
43 
 
 ing the said line to the end of five degrees of longitude 
 (the western limits of the province of Pennsylvania), 
 which, in the latitude of the said line, they find, and 
 the commissioners agree, to be two hundred and sixty- 
 seven miles, fifty-eight chains and ninety links,* the said 
 Indians alleging that they were instructed by their 
 chiefs in council, not to suffer the said line to be run to 
 the westward of the said war path," &c. &c. &c. 
 
 On Saturday, December 26th, 1767, the commission- 
 ers met and approved the conduct of the surveyors, in 
 desisting from the running of the parallel of latitude, 
 upon the opposition made thereto by the Indians, to 
 the full extent of five degrees of longitude from the 
 river Delaware, pursuant to their former instructions. 
 
 After describing the work thus far done, the com- 
 missioners agreed to discharge Messrs. Mason and Dixon 
 from their service, they having finished the lines they 
 were employed and sent over by the proprietors to run, 
 under the direction of the commissioners, of which they 
 gave the said Mason and Dixon notice, but agreed to 
 make them satisfaction for a draft or plan they were 
 instructed to prepare. 
 
 ^ :!: :;i :J: * * 
 
 The commissioners adjourned to meet at Chestertown, 
 Maryland, the 22d day of March, 1768, or such other 
 day as they may by letter agree upon. 
 
 * From our better knowledge of the dimensions and figure of the earth, we 
 should, at this day, compute these five degrees of longitude to be equal to two 
 hundred and sixty-six and thirty-one hundredths miles, or two hundred and sixty- 
 six miles, twenty-four chains and eighty links. J. D- G. 
 
44 
 
 After several meetings and adjournments of the com- 
 missioners, the proceedings of which are not necessary 
 to be noticed here, they met on 
 
 Saturday, November 5, 1768. 
 
 When " Mr. Ewing and Mr. Bordley informed the 
 other commissioners that, agreeable to the desire of the 
 commissioners, they have set up two stones, that is to 
 say, Mr. Bordley has put up one at the middle of the 
 due west line, run from Fenwick's Island [Cape Henlo- 
 pen] across the peninsula to Chesopeak Bay, in the 
 place of the post marked ' Middle.'* 
 
 " Mr. Ewing has put up the other in the due west 
 line, run in the parallel of latitude fifteen English statute 
 miles south of the most southern part of the City of 
 Philadelphia, at the intersection of the said west line 
 with the meridian run from the tangent jDoint ; the said 
 stones having the arms of Lord Baltimore graved on the 
 south and west sides thereof, and the arms of the pro- 
 j)rietors of Pennsylvania on the north and east sides 
 thereof," &c. &c. &c. 
 
 The following is an extract from the final report of 
 the commissioners, made to the proprietaries of the two 
 provinces, bearing date the 9th of November, 1768, 
 taken from the original records at Annapolis. It em- 
 braces a notice of all the lines and boundaries run out, 
 
 * The latitude of this Middle Point was determined, from astronomical obser- 
 vations made in October, 1766, by Messrs. Mason and Dixon, with a zenith sector 
 of six feet radius, to be 38° 27' 34". These observations were published in the 
 fifty-eighth volume of the Philosophical Transactions of the Royal Society of 
 London, for the year 1768. J. D. G. 
 
45 
 
 fixed, and determinedj under their direction, as well as 
 those run out by their predecessors, and adopted as true 
 boundaries, viz. : — 
 
 " 1st. We have completely run out, settled, fixed, 
 and determined a straight line, beginning at the exact 
 middle of the due east and west line mentioned in the 
 articles of the fourth of July, one thousand seven hun- 
 dred and sixty, to have been run by other commis- 
 sioners, formerly appointed by the said Charles Lord 
 Baltimore and the said Thomas Penn and Richard Penn, 
 across the peninsula from Gape Henlopen to Chesopeak 
 Bay, the exact middle of which said east and west line 
 is at the distance of thirty-four miles and three hundred 
 and nine perches from the verge of the main ocean, 
 the eastern end or beginning of the said due east and 
 west line ; and that we have extended the said straight 
 line eighty-one miles seventy-eight chains and thirty 
 links up the peninsula, until it touched and made a 
 tangent to the western part of the periphery of a circle 
 drawn at the horizontal distance of twelve English stat- 
 ute miles from the centre of the town of New Castle, 
 and have marked, described, and perpetuated the said 
 straight or tangent line, by setting up and erecting one 
 remarkable stone at the place of beginning thereof, in 
 the exact middle of the aforesaid due east and west 
 line, according to the angle made by the said due west 
 line, and by the said tangent line ; which stone, on the 
 inward sides of the same, facing towards the east and 
 towards the north, hath the arms of the said Thomas 
 Penn and Richard Penn graved thereon, and on the 
 
46 
 
 outwa,rd sides of the same, facing towards the west 
 and towards the south, hath the arms of the said Fred- 
 erick Lord Baltimore graved thereon ; and have also 
 erected and set up in the said straight or tangent line, 
 from the said place of beginning to the tangent point, 
 remarkable stones at the end of every mile, each stone 
 at the distance of, or end of, every five miles being par- 
 ticularly distinguished by having the arms of the said 
 Frederick Lord Baltimore graved on the side thereof 
 turning towards the west, and the arms of the said 
 Thomas Penn and Richard Penn graved on the side 
 thereof turning towards the east, and all the other in- 
 termediate stones are marked with the letter P on the 
 sides facing towards the east, and with the letter M on 
 the sides facing towards the west ; and have fixed in the 
 tangent point a stone with the arms of the said Fred- 
 erick Lord Baltimore graved on the side facing towards 
 the west, and with the arms of the said Thomas Penn 
 and Eichard Penn graved on the side facing towards 
 the east. 
 
 " 2idly. That from the end of the said straight line or 
 tangent point, w^e have run out, settled, fixed, and deter- 
 mined a due north line, of the length of five miles one 
 chain and fifty links, to a parallel of latitude fifteen 
 miles due south of the most southern part of the City 
 of Philadelphia, which said due north line intersected 
 the said circle, drawn at the distance of twelve English 
 statute miles from the centre of the town of New Castle, 
 one mile thirty-six chains and five links from the said 
 tangent point, and that in order to mark and perpetuate 
 
47 
 
 the said due north line, we have erected and set up one 
 unmarked stone at the point where the said line inter- 
 sects the said circle, three other stones at a mile distance 
 from each other, graved with the letter P on the sides 
 facing the east, and the letter M on the sides facing the 
 west, between the said place of intersection of the said 
 circle and the said parallel of latitude, and a third* 
 stone at the point of intersection of the said north line 
 and parallel of latitude ; which last stone, on the sides 
 facing towards the north and east, hath the arms of the 
 said Thomas Penn and Richard Penn graved thereon, 
 and on the sides facing towards the south and west hath 
 the arms of the said Frederick Lord Baltimore graved 
 thereon. 
 
 " ^dly. That we have run out, settled, fixed, and de- 
 termined such part of the said circle as lies westward 
 of the said due north line, and have marked and per- 
 petuated the same by setting up and erecting four stones 
 in the periphery thereof, one of which, at the meridian 
 distance of one mile from the tangent point, is marked 
 with the letter P on the east, and the letter M on the 
 west sides thereof 
 
 ^^Ulily. That we have run out, settled, fixed, and 
 determined a due east and we&t line, beginning at the 
 northern point or end of the said due north line, being 
 the place of intersection of the said north line with the 
 parallel of latitude, at the distance of fifteen English 
 statute miles due south of the most southern part of the 
 
 * This is evidently an inadvertent error in the original manuscript. It should 
 be a fourth stone, &c. J. D. G. 
 
48 
 
 City of Philadelphia, and have extended the said line 
 two hundred and thirty miles''' eighteen chains and 
 twenty-one links due west from the place of beginning, 
 and two hundred and forty-four miles thirty-eight chains 
 and thirty-six links due west from the river Delaware, 
 and should have continued the same to the end of five 
 degrees of longitude, the western bounds of the Pro- 
 vince of Pennsylvania, but the Indians would not permit 
 us. And that we have marked, described, and perpet- 
 uated the said west line, hy setting up and erecting 
 therein stones at the end of every mile, from the place 
 of beginning to the distance of one hundred and thirty- 
 two miles, near the foot of a hill called and known by 
 the name of Sideling hill, every five mile stone having, 
 on the side facing the north, the arms of the said 
 Thomas Penn and Richard Penn graved thereon, and, 
 on the side facing the south, the arms of Frederick 
 Lord Baltimore graved thereon; and the other inter- 
 mediate stones are graved with the letter P on the 
 north side, and the letter M on the south side ; and that 
 the country to the westward of Sideling hill being so 
 very mountainous as to render it in most places ex- 
 tremely difficult and expensive, and in some impracti- 
 cable, to convey stones or boundaries, which had been 
 prepared and marked as aforesaid, to their proper sta- 
 tions, we have marked and described the said line, from 
 
 =* This distance of two hundred and thirty miles ciglitccn cliains and twenty-one 
 
 links is erroneously printed two hundred and eir/ftfi/ miles, &e, &e., in McMahon's 
 
 History of Maryland, vol. i. See p. 40. 
 
 J. D. G. 
 
49 
 
 Sideling hill to the top of the Alleghany ridge, which 
 divides the waters runnino; into the rivers Potowmack 
 and Ohio, by raising and erecting therein, on the tops 
 of ridges and mountains o.ver which the said line passed, 
 heaps or piles of stones or earth, from about three and 
 a half to four yards in diameter, at bottom, and from 
 six to seven feet in height ; and that from the top of 
 the said Alleghany ridge, westward, as far as we have 
 continued the said line, we have set up posts at the end 
 of every mile, and raised round each post heaps or piles 
 of stones or earth, of about the diameter and heia;ht 
 before mentioned. 
 
 "Lastly. That we have, according to the said articles' 
 of agreement, made out, signed, and sealed a true and 
 exact plan and survey, as well of the due east and west 
 line, which was as aforesaid formerly run out by other 
 commissioners, appointed under the before-mentioned 
 articles of agreement of the tenth day of May, one 
 thousand seven hundred and thirty-two, and decree and 
 subsequent order aforesaid, running across the aforesaid 
 peninsula from the verge of the main ocean towards 
 Chesopeak Bay, but stopping in the exact middle of the 
 said peninsula, as of such parts of the said circle, lines, 
 marks, and boundaries as have been marked, run out, 
 settled, fixed, and determined, in manner aforesaid, by 
 the respective commissioners who have been for that 
 purpose appointed, subsequent to the before-mentioned 
 articles of agreement of the 4th da}^ of July, one thou- 
 sand seven hundred and sixty, which plan and survey 
 we have hereunto annexed. 
 4 
 
50 
 
 " In testimony whereof we have hereto set our hands 
 and seals, at Chestertown, in the Province of Maryland, 
 the 9th day of November, in the 9th year of the reign 
 of our Sovereign Lord, George the Third, King of Great 
 Britain, &c., and in the year of our Lord one thousand 
 seven hundred and sixty-eight." 
 
 Then follows the certificate placed upon the map, 
 recorded in the proceedings of that date, and the whole 
 is signed by 
 
 HOR'O SHARPE, WILL. ALLEN, 
 
 J. EIDOUT, BENJAMIN CHEW, 
 
 JNO. LEEDS, JOHN EWING, 
 
 JOHN BARCLAY, EDW'D SHIPPEN, Jr. 
 
 GEO. STEUART, THOS. WILLING. 
 
 DAN. OF ST. THOS. JENIFER, 
 
 J. BEALE BORDLEY. 
 
 I have been thus full in the extracts and minutes 
 from the original manuscripts at Annapolis, because 
 they appear necessary to a clear iniderstanding of the 
 lines we were required to examine, and because we 
 shall have occasion to refer to many of the facts therein 
 set forth, as having an important relation to our own 
 survey. 
 
 On the 9th of November last I went to New Castle, 
 and on the lOtli to Philadelphia, to obtain the instru- 
 ments in depot there which were required for our sur- 
 veys. On the 12th, having met your board in confer- 
 ence, at Wilmington, Delaware, I was invited to prepare 
 and present for your consideration and approval a de- 
 tailed plan of the field operations necessary to the 
 
61 
 
 accomplishment of the objects pomted out by you. I 
 requested an opportunity of previously making a recon- 
 noissance of the line and of the landmarks within the 
 limits of the portion of boundary in question, which 
 was assented to ; and on the same day I accompanied 
 the board to Newark, Delaware, which was decided on 
 as the most convenient head-quarters of the Engineers 
 during the field operations. 
 
 The 13th and 14th of November were spent in 
 making the proposed reconnoissances in company with 
 your board. 
 
 We proceeded to the north-east corner of Maryland, 
 or point of intersection of the due north line with the 
 parallel of latitude fifteen miles south of the parallel 
 of the most southern limit of Philadelphia. This point 
 is in a deep ravine, on the margin of a small brook, and 
 near its source. The stone monument with the arms 
 of Lord Baltimore and Thomas and Richard Penn gra- 
 ven thereon, which had been placed by commissioner 
 Ewing, by order of the board of commissioners in 1768, 
 to designate this point, was missing.* From the tra- 
 dition of the neighborhood, it appeared that some years 
 ago, after it had fallen nearly prostrate from its place, 
 owing to the encroachment of the stream, upon whose 
 margin it stood, some individual had taken it away for 
 a chimney-piece. A stake was found firmly jDlanted in 
 the ground, which, we were informed by the neighbors 
 near by, occupied its place. 
 
 * See the proceedings of the Commissioners, under date of November 5th, 
 1768, noticed at page 44. 
 
52 
 
 From this point we proceeded to the west, and found 
 the first, second, and third mile stones on the parallel of 
 latitude marked with the letter M on the south, and the 
 letter P on the north sides, as described in the proceed- 
 ings of the commissioners of boundary of that period. 
 The first of these stones was much inclined in its pos- 
 'ture, and somewhat infirm. 
 
 We next proceeded to examine the line south from 
 this corner, with the view of ascertaining if the stones 
 at the intersection of the due north line with the 
 peripher\^ of the circle, and at the tangent point, were 
 standing. We extended our examinations to the south, 
 'Upon the tangent line, as far as the seventy-ninth mile 
 stone from the " Middle Point " of the peninsular line. 
 We found a number of stones on the line, some un- 
 marked, which we supposed to be on the circumference 
 of the circle. With a radius of twelve miles, such a 
 ^curve is so flat that it is difficult in walking over ground 
 intersected with forest timber, fences, and other ob- 
 structions, to distinguish, withouti^the aid of instruments, 
 the deflections of the lines connecting monuments on 
 its circumference nearly a third of a mile apart. Two 
 of the monuments visited were graven on their east and 
 west sides with the arms so often described in the pre- 
 ceding documents. One of these was near Jesse Up- 
 degrove's house, and the other in Mr. Reynolds's field, 
 just north of the railroad track. 
 
 This last I supposed to be the stone erected to mark 
 the tangent point, as the arms were graven upon it, and 
 it was much less than five miles (indeed, not quite three 
 
53 
 
 miles), from the jDreceding one, marked in a similar man- 
 ner to the southward. The nearest neighbors possessed 
 no knowledge whatever of the particular point intended 
 to be marked by this stone. A vague impression pre- 
 vailed that it did not now occupy its original position, 
 but that it had been disturbed at some distant but un- 
 known period. On questioning the individuals who 
 entertained this impression as to their reasons, it was 
 stated that within the recollection of some of the in- 
 habitants, fragments of stone, similar both in quality 
 and in cutting to the portion now seen above ground, 
 lay strewed at its base. The inference was that the 
 stone was fractured near its base when taken up, and 
 that the fragments seen were originally a portion of it. 
 An impression likewise prevailed that the stone origin- 
 ally planted at the point of intersection of the due 
 north line with the arc of the circle of twelve miles 
 radius, corresponding at this day with the true point of 
 junction of the three States of Pennsylvania, Maryland 
 and Delaware, was also missing. 
 
 These were jDoints that could only be settled by an 
 accurate survey of the portion of the boundary involved 
 in doubt or uncertainty, and a comparison of the result 
 of such survey with what ought to exist in conformity 
 with the minute details contained in the recorded pro- 
 ceedings of the old commissioners and of their surveyors. 
 
 This course was suggested to your board, and met 
 your approbation. 
 
 On consultation with the board, and by its approba- 
 tion, I immediately called to my assistance Lt. Thom, of 
 
54 
 
 the Topographical Engineers, and Mr. Charles Radzi- 
 niinski, civil engineer, who were assisted by Mr. Henry 
 C. Derrick as sub-assistant ; and the requisite chain bear- 
 ers, axemen, &c., and means of transportation on the 
 line, having been provided by yon, the survey was com- 
 menced on the 16th of November, with a portable tran- 
 sit instrument having an azimuth circle for measuring 
 horizontal angles, divided to read by aid of the vernier 
 to minutes, and a chain of one hundred feet divided 
 into one hundred links of a foot each, and a standard 
 five feet rod, of wood, with which the chain was com- 
 pared several times every day, in order to reduce the 
 chaining to correct measure. 
 
 It was necessary, in this survey, and upon the maps 
 designed to accompany it, that we should exhibit a por- 
 tion of the tangent line, in order to lay down its true 
 point of intersection with the due north line, for the 
 purpose of testing the tangent point. Accordingly, we 
 began at the stone marking the seventy-ninth mile of 
 Mason and Dixon, reckoned from the middle point of 
 the peninsular west line, having the letter M engraved 
 on the west and the letter P on the east side ; and run- 
 ning northerly to a signal placed at the base of the 
 eightieth mile stone, we thus obtained the direction of 
 the tangent line. This eightieth mile stone is engraved 
 with the arms of Lord Baltimore and the Penn family 
 on the west and east sides respectively, precisely as 
 described in the old records. Continuing in this initial 
 direction, by the aid of the transit, our line passed im- 
 mediately over the eighty-first mile stone of Mason and 
 
55 
 
 Dixon, engraved with the letter M on the west and the 
 letter P on the east side, and also immediately over the 
 next stone, which, being engraved with the arms of 
 Lord Baltimore on the west and with the arms of the 
 Penn family on the east side, was recognized to be the 
 tangent point. 
 
 We here deflected at a trial ansrle of 3° 32' to the 
 eastward of the prolongation of onr previous line, and 
 pursuing accurately a straight course, we passed four 
 stones on our left, to which offsets were measured, at 
 right angles to our line. The first, second, and fourth 
 of these stones were unmarked, but were cut in pris- 
 matic form, and rounded at their tops. The third, which 
 at the distance of five thousand one hundred and fifty 
 feet from the tangent stone was 95. 3* feet perpendicular 
 and to the west from our line, was marked with the 
 letter P on the east side and the letter M on the west 
 side, and is the stone mentioned in the report of the 
 commissioners of November 9, 1768, as being at the 
 meridian distance of one mile from the tangent point. 
 
 These four stones were now recoo;nized to be those 
 described in the proceedings of the commissioners of 
 June 17 and 18, 1765, already quoted, and also in 
 their aforesaid report (see page 47), as marking the 
 arc of the circle of twelve miles radius, west of the due 
 north line. It seems they were never substituted by 
 stones bearing the arms of the proprietaries, as was 
 contemplated to be done at some subsequent and con- 
 
 * This offset becomes 101.4 feet from the due north line, as will hereafter 
 appear. J. T>. G. 
 
56 
 
 venient period, when they were planted by the com- 
 missioners in 1765. 
 
 At the distance of 7,743.7 feet from the tangent 
 stone, we reached an unmarked stone. Om^ trial line 
 terminated nine feet west of it, measm^ed at right angles 
 to the line we had run upon. This stone was recognized 
 to be the point marked in 1765 for the intersection of 
 the due north line with the periphery of the circle of 
 twelve miles radius, and stood now for the point of 
 junction of the three States. 
 
 At every five hundred feet from the tangent stone, 
 and also opposite to each of the stones on the arc of 
 the circle to which offsets were made while running 
 this experimental line, we had driven a wooden stake. 
 These were regularly numbered from one to nineteen 
 inclusive. We now computed the angle at which we 
 should, at the tangent stone, have deflected to the right 
 from the prolongation of the tangent line, to obtain the 
 true direction, in a straight line, to the stone intended 
 by Messrs. Mason and Dixon to mark the intersection 
 of the due north line with the p^eriphery of the circle, 
 and found it to be 3° 36' 09". 
 
 By computation w^e also determined the points, and 
 drove a new line of stakes opposite to the former ones, 
 to mark this true direction, and determined the lengths 
 of the offsets to the stones on the arc of the circle at 
 right angles from the said new line. 
 
 Taking up the new direction, obtained by comj)uta- 
 tion, we continued our survey to the north, noting the 
 topography, and carefully measuring offsets to the right 
 
57 
 
 and left, to all houses, fences, streams, and other remark- 
 able objects within a reasonable distance, as indeed we 
 had done from the beginning of the survey. 
 
 Our line passed over three boundary stones marked 
 with the letter P on the east, and with the letter M on 
 the west sides, corresponding with the description given 
 — by the commissioners in their report, and by Mason 
 and Dixon in their notes of survey, — of the three stones 
 on the due north line, north of the portion of the circle 
 run out and fixed by them ; and at its termination, our 
 line passed immediately over the stake already men- 
 tioned as having been found by us in our reconnoissance 
 of the loth of November, which was said to mark the 
 point where the old stone had stood, at the intersection 
 of this due north line with the east and west line of 
 Mason and Dixon, marked with the arms of Lord Balti- 
 more and the Penn family. We did not deviate two 
 inches to the right or the left of the centre of this stake. 
 It was on the 20th of November that our survey reached 
 this point. 
 
 On the following day we proceeded to find the true 
 point of intersection of the east and west line of Mason 
 and Dixon with this due north line. 
 
 Beginning at the second mile stone west of the re- 
 quired point on Mason and Dixon's parallel of latitude, 
 we traced out this parallel due east, and at the distance 
 of five thousand two hundred and ninety-five feet, by 
 our measurement, we touched upon the first mile stone 
 on this parallel. Continuing upon the same parallel of 
 latitude, at the distance of five thousand two hundred 
 
58 
 
 and eiglity-two feet, by our measurement, from the pre- 
 ceding stone, we struck the same stake at which our 
 north line had terminated, at a point about one inch 
 north of its centre. 
 
 This last line traversed portions of thick forest, 
 through which we were obliged to open vistas : and in 
 several places trees of large size, standing in open 
 ground, had to be cut down to admit of its prolonga- 
 tion, which proved that there could have been no 
 retrace of it until now, since the days of Mason and 
 Dixon. 
 
 Having thus, by the intersection of the due north 
 line with the parallel of latitude, found the true position 
 of the lost monument, we proceeded to mark and per- 
 petuate it by planting the new monument, which had 
 been prepared under the immediate direction of your 
 Board for that purpose. 
 
 Before making the necessary excavation, the point to 
 be occupied by the centre of the base of the stone was 
 preserved by placing four pegs nearly in the form of a 
 square, so that the intersection of their diagonals should 
 correspond with the said point. The next step was to 
 construct a dam to turn off the water of the small brook 
 which washed almost the very point, and thus prevent 
 its filling the cavity. 
 
 In making the excavation, we found at the depth of 
 about three feet below the surface a cut stone unmark- 
 ed, and of precisely the same form, dimensions, and 
 quality as the unmarked stones on the arc of the circle. 
 
59 I 
 
 and at the intersection of the circle with the due north 
 line, already described. 
 
 In turning to the proceedings of the commissioners, 
 under the dates of the 17th and 18th of June, 1765, 
 we find that such a stone was placed by them, to mark 
 that point, on the last-mentioned day. (See pages 38 
 —40.) 
 
 It was not until the year 1768, that a second stone, 
 marked with the arms of the proprietaries, was also 
 placed at this point, as will be seen by the records of 
 the proceedings of the commissioners of November 
 5th of that year. (See page 44.) 
 
 It is quite within the memory of the neighboring 
 inhabitants that the stone which stood at this point in 
 a tottering posture, to within a few years past, bore the 
 arms, so often described, graven upon it. 
 
 The unmarked stone of 1765 had probably been 
 buried at the base of the one bearing the arms, when 
 the latter was placed at the same point by commissioner 
 Ewing, in 1768. 
 
 The evidence afforded by the disinterment of this old 
 stone, that the point fixed upon from our survey, as the 
 intersection of the due north line with the parallel of 
 latitude fifteen miles south of the most southern limit 
 of the city of Philadelphia, (being the north-east corner 
 of Maryland,) corresponds so well with that originally 
 established by Messrs. Mason and Dixon, is certainly 
 gratifying. 
 
 The new stone re-marking this important point was 
 planted with its base resting on rock, about five feet 
 
60 
 
 below the surface of the ground, and its top rising about 
 two feet above the ground. It is of cut granite, and of 
 the following dimensions, viz.: about seven feet long, 
 and squares sixteen by eighteen inches. It is marked 
 with the letter M on the south and west sides, and the 
 letter P on the north and east sides. Under this letter, 
 on the north side, the date 184D is engraved in deep 
 cut figures. 
 
 The striking discrepancies between some of our meas- 
 ured distances and those of Messrs. Mason and Dixon, 
 and their bearing upon the demarcation of the arc of 
 the circle west of the due north line, as well as upon 
 the true relative positions of the tangent stone, and the 
 stone representing the intersection of this circle with 
 the due north line, renders it proper that we should 
 here institute a comparison between them, with a view, 
 especially, to ascertain whether there were good reasons 
 for the impression which prevailed, that one or both of 
 the last-mentioned stones had been removed from their 
 original position. 
 
 If it were true that these important monuments had 
 been disturbed, no approximate estimate could be 
 formed of the extent of mischief thus perpetrated 
 upon the boundaries, without such investigations as 
 would lead to a discovery of their original and rightful 
 positions. The ascertainment of the true point of 
 junction of the three States was involved in this ques- 
 tion, and this was the chief object to be investigated 
 and adjusted under the especial legislation of those 
 States authorizing your proceedings. In regard to 
 
61 
 
 Delaware, an impression prevailed among her citizens 
 that a considerable portion of her territory had been 
 abstracted by the curtailment of her rightful radius of 
 twelve miles around New Castle. The unlawful dis- 
 turbance of these monuments, if true, might well have 
 produced such an effect, and it lay within the powers 
 delegated to you to correct the wrong, if it could be 
 proven to be owing to such a cause. 
 
 The comparison is embodied in the following tabular 
 statement, viz. : 
 
62 
 
 
 03 . 
 
 
 lO o 
 
 ^ 
 
 10 CO G<) 
 
 
 g^ 
 
 o 
 
 c-i O Ol 
 
 o -t! 
 
 CO lO (M UO 
 
 
 sg-M 
 
 03 
 
 CO CO G<l 
 + + 1 
 
 CO CO 
 
 7 + 
 
 + ^ 
 
 
 
 
 
 lO Ci 
 
 r^ 
 
 CO c- 
 
 
 ■m" 
 
 G^l O lO 
 
 O CO 
 
 >o CO 10 Ci cq 
 
 
 ^ 3 1 
 
 03 
 
 CO CO -1^ 
 
 u- O 
 
 1— 1 1— 1 1— 1 
 
 
 f^ 
 
 T— 1 
 
 i-H >!:H 
 
 (M T-t 
 
 
 CO « CTl 
 03 CS Tf 
 
 
 lO" 
 
 >o" C<f 
 
 
 
 O 03 00 
 
 
 
 
 
 
 
 
 
 
 
 t^ ^ s 
 
 S 
 
 1— 1 I— 1 o 
 
 O i-H 
 
 T— 1 1— 1 T-H iH tH 1— 1 
 
 
 
 ^ 
 
 
 
 
 
 n 
 
 
 1 
 
 CO 
 
 
 
 s S 
 
 o 
 
 03 
 
 
 1 00 
 
 
 o 
 
 
 
 
 Oi 
 
 
 
 
 (V) f^ 
 
 
 1 ^ 
 
 
 t^ 
 
 
 
 
 Ci 
 
 
 
 
 i ^ 
 
 Pq 
 
 
 1 '"' 
 
 
 CO 
 
 cm" 
 
 
 
 
 
 
 
 
 
 
 
 
 
 _s 
 
 ^ T-H O 
 
 I— 1 tH 
 
 T—l 1— 1 rH .— 1 I— ( i-H 
 
 H 
 
 
 s 
 
 
 
 
 ;5 
 
 
 
 
 
 
 H 
 s 
 
 H 
 
 
 
 <S 
 
 o 
 
 e due 
 miles 
 f the 
 
 ^ 
 
 
 ■ ^ 
 p 
 
 
 . 1^ 
 
 
 1-^ 
 
 
 
 CO 
 
 s 
 
 p., 
 
 f-l 
 o 
 
 03 
 3 
 
 f-l 
 
 3rsection of tli 
 'cle of twelve 
 of junction o 
 
 o 
 
 03" 
 > 
 
 B 
 
 r^ 
 03 
 
 
 • 6 
 
 a 
 
 ■ CO 
 
 :o 
 
 
 . c 
 
 . 
 
 CO 
 
 • 03' 
 
 • .s 
 
 - CO 
 . 03 
 
 • ^ 
 
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 'S 
 
 -4-3 .C- ^-^ 
 
 c 
 
 
 
 
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 03 C 
 
 03 
 
 ' G ^ c 
 
 
 
 "co 
 
 
 ■ 03 
 
 
 t(-i 03 
 
 03 
 
 EH 
 
 d 
 
 
 n to 
 
 tw 
 
 ' 'Z3 "*^ 
 
 nzJ 
 
 
 . 
 
 
 r=! 
 
 . CO 
 
 1 
 
 
 J - 
 
 O 
 
 o 
 
 : I'^'^l 
 
 
 
 
 ^co 
 
 ' 03 
 
 
 5-1 S 
 
 03 
 
 r-i .^ 
 
 • "a 
 
 • 
 
 
 e-. 
 
 o 
 o 
 
 TJl 
 
 o 
 
 
 stone, on the 
 . to the tange 
 
 tone on the ai 
 the east side, 
 one representi 
 circumference 
 day marking 
 
 s 
 
 
 -2 
 
 'co 
 
 
 
 
 
 c- 
 C 
 
 C 
 
 ■ s 
 
 '.m 
 
 i 6 
 
 ]3 
 
 '. at Gibson's, 
 north-east eon 
 ryland to Isl 
 
 S 
 
 
 
 CO 
 
 
 H 
 
 1— 1 
 
 
 th mile 
 
 st 
 
 e on do 
 
 to the s 
 1 P on 
 :o the st 
 ith the 
 at this 
 
 03 
 
 
 
 
 
 's to do 
 )n's to 1 
 of Ma 
 
 
 
 03 
 
 
 P 
 
 
 OD CO O 
 
 ;i -*- e , CO ^ 
 
 03 S 03 '^ 03 'X; 
 
 .SO 
 
 — C3 
 
 'o ^ t-i 03 g 
 
 03 -^ 03 c -i:i 
 
 
 
 
 79th to the 
 80th to the 
 81st mile SI 
 
 tangent sto; 
 the west 
 
 tangent stoi 
 
 north lini 
 
 radius, a 
 
 three Sta 
 
 nt on due no 
 
 m due north 
 e stone at M 
 
 north line, 
 e stone at St 
 e stone at G 
 rth-east corn 
 s due west li 
 
 to 2d mile s 
 
 
 
 
 
 
 2Sr=iSS^oi-i 
 
 
 
 
 'A 
 
 s 
 
 5 g c s s S5 s 
 
 cooooool— lo 
 
 
 
 
 o 
 
 o 
 
 
 
 
 
 
 t-( iH !-< ;h t-l 
 
 
 
 
 ^ 
 
 
 
 
 ^ 
 
 
 F=^ 
 
 ^ 
 
 P^P^H 
 
 f^ 
 
 ci s "^^ 
 
 ^ 03 § ° 
 
 03 ^ _j 03 
 
 03 .2 •- 
 
 ci 
 
 5 " 
 
 >^; 
 
 i S o 
 
 — 03^ O 
 
 bo 
 
 ?' 03 .S 
 
 a 
 
 
 § 03 cj'" 
 03 CC 5 S 
 
 O O 
 
 o £; 
 o 
 
 u 
 
 T^ "5 =3 
 
 5= 
 
 3 -^ 
 
 
 
 
 
 c^ 
 
 ^-S'g 
 
 C 
 
 
 
 
 -^ . 
 
 P 
 
 ■^ ^ ?, 
 
 3 
 
 eg S 
 
 ^ 
 
 p2h-^ 
 
 
 
 CO 03 
 
 r-" 03 
 
 13 -S 
 
 
 S^- 
 
 03 
 
 P o.S 
 
 .^ 
 
 c^ ^ 
 
 a 
 
 
 
 ■ti ci 
 
 ^-■B 
 
 
 ^ p £ 
 
 ?^ 
 
 ^■5 
 
 %^ 
 
 h? .r: -= ^^ 
 
63 
 
 The first discrepancy to be investigated was in regard 
 to the length of the chord of the arc cnt off hy the 
 due north line. 
 
 We, therefore, retraced it by running a straight line 
 from the tana^ent stone to the stone set bv the old com- 
 missioners to mark the intersection. In addition to the 
 first measurement of this chord, already given, two 
 others w^ere carefully made. The following is a state- 
 ment of the results of the three, viz. : 
 
 By the first measurement, 7,743.7 feet. 
 
 By the second measurement, 7,742.2 " 
 
 By the third measurement, 7,743.1 " 
 
 Mean of the three, 7,743. " 
 
 Length of this chord, given by Mason 
 and Dixon, is one mile, thirty-six 
 chains and five links, equal to 7,659.3 " 
 
 Our measurement is greater than the 
 
 length given by Mason and Dixon by 83.7 " 
 
 Again : Mason and Dixon state the meri- 
 dian distance from the tangrent stone 
 to the marked or third stone on the 
 arc of the circle to be one mile, or-- 6,280 feet. 
 
 Our measurement gives this distance,-- 5,150 " 
 
 Our measurement is less than the dis- 
 tance given by Mason and Dixon, by 130 " 
 
 These differences not only cast, at the moment, strong 
 suspicion upon the present positions of the tangent and 
 
64 
 
 the intersection stones, but they also affect, in a very 
 important degree, the elements of the circle, an, arc of 
 which was to mark a part of the boundary between 
 Maryland and what is now the State of Delaware. 
 
 We had computed the angle of deflection between the 
 prolongation of the tangent line and the due north line 
 to be 3° 36' 09"; and the measurement of that angle 
 afterwards, with the theodolite, i verified sufficiently the 
 accuracy of that computation ; for we finally found it, 
 by a number of measurements repeated on all parts of 
 the limb of the instrument, to be 3° 36' 06". 
 
 With this angle, and the length of the measured 
 chord, the length of the corresponding radius was com- 
 puted on the supposition that the stones on the arc of 
 the circle truly marked that arc. 
 Makino; c =1 the chord. 
 
 d z= the angle of deflection from the 
 
 tangent line to that chord. 
 r = the radius. 
 
 c . cosine d 
 
 We will have r = — : ^ ., . 
 
 sme Ji a 
 
 By this equation, with the angle of deflection above 
 given, and the chord, as given by Mason and Dixon, of 
 one mile, thirty-six chains and five links, the correspond- 
 in «- radius is eleven miles and two thousand three hun- 
 dred and two feet, or 11.44 miles. 
 
 With the same angle of deflection, and the chord of 
 seven thousand seven hundred and forty-three feet, 
 which is the actual distance between the tangent and 
 intersection stones, the corresponding radius is eleven 
 
65 
 
 miles and two thousand nine hundred and sixty-two 
 feet, or 11.56 miles. 
 
 We now made a trace of the curve upon the ground, 
 corresponding to a radius of twelve miles. The length 
 of a chord subtending an angle of one degree, at the 
 centre of a circle of that radius, was computed to be 
 l,105nj feet ; and departing from the tangent stone by 
 a deflection, in the first place, of half a degree from the 
 prolongation of the tangent line, to obtain the first 
 chord, and afterwards by deflections of a degree from 
 chord to chord of the above-mentioned length, a number 
 of points were obtained upon the circumference of the 
 portion of the circle west of the due north line, which, 
 thus traced, intersected the due north line two hundred 
 feet in advance, or north of the position of the stone 
 placed, in 1765, to represent that point of intersection. 
 
 We next computed the length of the chord actually 
 corresponding to the angle of deflection of 3° 36' 06", 
 and a radius of twelve miles, by the equation 
 
 r . sine .2 d 
 cosine d 
 and found it to be 7,960.. 6 feet, which is three hundred 
 and one feet four inches longer than that given by the 
 survey of Mason and Dixon, and two hundred and 
 seventeen feet five inches longer than the actual distance 
 between the tangent stone and the intersection stone. 
 
 In this state of the investigation, it was determined, 
 
 upon my recommendation to your Board, representing 
 
 to you, at the same time, the necessity of the measure 
 
 to a satisfactory solution of the problem involved, that 
 
 5 
 
66 
 
 the actual length of the radius or distance from the 
 spire of the court house at New Castle, to some point 
 on the curve, as marked by the old monuments, should 
 be accurately ascertained by a triangulation, which 
 should be extended so as to give also the correct dis- 
 tances both from the tangent stone and the intersection 
 stone, to the north-east corner of Maryland. The last- 
 mentioned point, in case of any future disturbance of 
 its monument, may always readily be found, as it is the 
 intersection of two lines, both easily traced. Hence, 
 knowing the distance from it to the other two, all three 
 being upon the same meridian, a certain guide would 
 be obtained for restoring either of the latter to its 
 proper position, if disturbed. 
 
 The distances given by the chain measurements of 
 Mason and Dixon are already shown to be too inaccu- 
 rate to serve for such a guide. 
 
 On the 24th of November, I proceeded to Washing- 
 ton to ascertain if the records of the coast survey office 
 could furnish us a distance, from its triangulation in this 
 vicinity, that would serve as a convenient base for our 
 triangulation. And I have much pleasure here in ac- 
 knowledging the courtesy and promptness with which 
 Professor A. D. Bache, superintendent of that work, 
 had the records examined, and furnished me, from them, 
 several distances and azimuths which were determined 
 some years past, when that work was under the super- 
 intendence of the late Mr. Hassler, and also, sketches of 
 the localities of the several stations, to aid us in finding 
 the concealed monuments by which they were per- 
 petuated. 
 
67 
 
 Some calculations had to be made in order to prepare 
 them, and they were forwarded to me at Newark, on 
 the 9th of December, after my return to that place. 
 
 Among them we found the following suitable to our 
 object, viz. : 
 
 1. From Iron Hill to New Castle court house : 
 
 Distance, 16,281.57 metres.* 
 
 2. From Gray's Hill to Iron Hill : 
 
 Distance, 4,847.44 metres ;f 
 Azimuth, 233° 48' 07".8.t 
 
 The last-given distance was adopted as our base in 
 the triangulation, and the necessary preparations were 
 commenced for carrying it on with an excellent theodo- 
 lite of nine inches diameter, § reading with three ver- 
 niers to fifteen seconds each, made by E. Draper, of 
 Philadelphia. 
 
 In the mean time, a retrace of the arc of the circle 
 west of the due north line was carried on. 
 
 On the 9th and 10th of December it snowed heavily. 
 
 On the 11th, the weather was clear, but very cold, 
 with the snow nine inches deep upon the ground. The 
 work was, however, prosecuted with assiduity, notwith- 
 
 ^ Equal to 53,415.1 feet. > At the rate of 39.36850535 inches to the metre, as 
 
 t Equal to 15,903 feet. ) adopted by the coast survey. 
 
 f The azimuth is reckoned from the south as 0, round by the west, north, and 
 east to the south, making 360°. 
 
 § On the 29th of January, while Mr. Eadziminski was observing with this 
 theodolite, during a violent gale of wind, the heavy tripod station above him was 
 blown over, and fell to the ground. It struck and demolished the instrument, and 
 Mr. R. narrowly escaped being killed; the largest timber just brushing his head, 
 without, however, injuring him. This instrument was then substituted by another 
 which I had in depot at Philadelphia. 
 
68 
 
 standing there was great difficulty in clearing the lines 
 through the woods^ in consequence of the weight of 
 snow upon the branches of the trees. 
 
 The second trace of this curve verified the accuracy 
 of the first. The direction of the tangent line south- 
 ward from the tangent stone, was also re-examined and 
 verified. 
 
 The engineers were then occupied in making the 
 requisite reconnoissances of the surrounding country, in 
 order to select suitable positions for our trigonometrical 
 stations — in erecting those stations, and directing the 
 opening of vistas through the interposing forest to 
 render those stations visible one from another. 
 
 The severity of winter had fully set in. Notwith- 
 standing this, the engineers were actively employed, 
 whenever the weather was clear enough to see the sta- 
 tions, in making the necessary observations ; and, when 
 prevented from observing for want of a clear atmos- 
 phere, they were engaged in completing the erection 
 of the stations and directing the clearings, a work which 
 they forwarded with every possible assiduity, often in 
 the rain and snow. 
 
 The coast survey stations at Iron Hill and Graj^'s Hill, 
 were discovered buried between two and three feet 
 below the surface of the ground. They were not 
 disturbed, but their centres were indicated in position 
 by the intersection of the diagonal lines of a quadrangle 
 formed by four pegs, driven into the ground, about 
 eight feet apart. Then the cavities were carefully filled 
 again with earth, and a peg driven at the intersection 
 
69 
 
 of these diagonal lines to mark the extremities of om^ 
 base line. In searching for the buried station at Gray's 
 Hill, we could find only one of the points of reference 
 given us in the sketches from the coast survey office, 
 with its distance from the station. 
 
 The snow then lay six inches deep upon the ground, 
 and the mode adopted to find this point was to take 
 the stated distance on a cord line, and, attaching one 
 end of it to the given point of reference, to describe 
 an arc of a circle covering the probable limits. 
 
 The snow was then removed from this arc, and after- 
 wards a trench was dug in the ground, following the 
 curve until the station was found. 
 
 The trigonometrical stations are all laid down in posi- 
 tion on the accompanying maps ; where, also, the whole 
 triangulation is shown. These stations were marked 
 upon the ground by tin cones fixed to the tops of stout 
 poles, supported by tripods of heavy undressed timbers, 
 giving them an elevation of sixty to seventy feet above 
 the ground. The cones were adjusted perpendicular 
 over the points marked upon the ground by short stakes, 
 over which the centre of the theodolite was placed, 
 when the angles were observed. 
 
 The tangent stone, and the stone fixed at the north- 
 east corner of Maryland, stood in such low depressions 
 in the ground that stations could not be erected at 
 either of them high enough to be seen from the base 
 stations, or, indeed, from any two of the other stations, 
 suitable for fixing their positions. Two stations were, 
 therefore, erected on the due north line, as near to them 
 
70 
 
 as possible ; one on the chord of the arc, at the meas- 
 ured distance of 1,701.02 feet north from the tangent 
 stone, and the other on the due north line, at the meas- 
 ured distance of 730.4 feet* south of the monument at 
 the north-east corner of Maryland. 
 
 The distance between the trigonometri- 
 cal stations on the north line was 
 found by our triangulation to be 24,139.5 feet. 
 
 Distance from the south station on 
 the north line to the tangent stone 
 (twice measured), 1,701.02 " 
 
 From the north station on the north line 
 to the monument at the north-east 
 corner of Maryland (twice meas- 
 ured), 730.42 « 
 
 The sum = the distance from the tan- 
 gent stone to the north-east corner 
 
 • of Maryland, 26,570.94 
 
 Or, five miles and 170.94 feet. 
 
 Deducting from the above our meas- 
 ured distance from the tangent stone 
 to the intersection stone, — 7,743 
 
 a 
 
 i( 
 
 We have the true distance from the 
 intersection stone to the north-east 
 corner of Maryland, = 18,827.94 « 
 
 Or, three miles and 2,987.94 feet. 
 
 L, UJ.iXv.v. Xi.xxiV.^J l.JXivi ^y 
 
 * This is the chained distance, corrected to correspond with the point perpen- 
 dicular under the cone. J. D. G. 
 
71 
 
 The distance from the spire of the 
 court house at New Castle to the 
 station on the arc of the circle^ 
 which is the actual radius of the 
 circle, marking in part the boundary 
 between Delaware and Maryland, 
 was determined by our triangulation 
 to be 63,357.7 feet. 
 
 Or, two feet and four inches less than the stipulated 
 radius of twelve miles. 
 
 During the investigations in relation to the arc west 
 of the north line and its chord, I found it necessary to 
 go again to Annapolis, in order to see if a further 
 search into the notes of Mason and Dixon's survey 
 would afford any explanations of the principles upon 
 which they traced this arc, and determined the length 
 of its chord. These notes, added to those of their pre- 
 decessors, and the records of the commissioners of that 
 period, were too voluminous for me possibly to finish 
 their perusal and close examination within the period 
 of my first visit. 
 
 The information derived from them, combined with 
 our determinations of the actual length of the radius, 
 and the angle of deflection between the tangent line 
 prolonged, and the north line, served to elucidate the 
 whole difficulty, which had arisen (where it was least 
 to be expected) in an evident error in a governing 
 element in their computation of the length of this 
 
72 
 
 chord, and, consequently, of the lengths of the ordinates 
 at right angles to it, which was the method adopted by 
 them for marking the points upon the arc west of the 
 north line. 
 
 The foUowino; is an extract from the records of their 
 survey : 
 
 "1765, June M. Sent expresses to Annapolis and 
 Philadelphia, to acquaint the commissioners we should 
 finish the line betwixt the tangent point and the parallel 
 this week. 
 
 " Also measured the angle formed by the radius from 
 New Castle and the north line, and found it ■= 86° 32'. 
 Hence the offsets (at right angles) to the westward from 
 the meridian for the boundary betwixt New Castle 
 county and Maryland are as follows : — 
 
 Distance from tangent 
 
 Offsets. 
 
 
 point. 
 
 
 
 
 
 No. 
 
 Cliains. 
 
 Links. 
 
 Chains. 
 
 Links. 
 
 
 
 
 
 
 00 
 
 
 
 00 
 
 
 1 
 
 8 
 
 05 
 
 
 
 46 
 
 
 2 
 
 18 
 
 05 
 
 
 
 92 
 
 
 3 
 
 28 
 
 05 
 
 
 281 
 
 
 4 
 
 ,38 
 
 05 
 
 
 o4| 
 
 
 5 
 
 48 
 
 05 
 
 
 70i 
 
 
 6 
 
 58 
 
 05 
 
 
 751 
 
 " = the middle or greatest offset." 
 
 7 
 
 68 
 
 05 
 
 
 701 
 
 
 8 
 
 78 
 
 05 
 
 
 541 
 
 
 9 
 
 88 
 
 05 
 
 
 281 
 
 
 10 
 
 98 
 
 05 
 
 
 
 92 
 
 
 11 
 
 108 
 
 05 
 
 
 
 46 
 
 
 12 
 
 116 
 
 05 
 
 
 
 00 
 
 
 
 
 
 
 CHA. MASON, 
 
 
 
 
 
 
 JERE. DIXON." 
 
 " 1765, June ith. Set off the offsets," &c. 
 
73 
 
 We find, on investigation, that the foregoing elements 
 of the arc of Mason and Dixon are based upon the 
 angle of deflection of the chord, from the tangent line 
 produced, of 3° 28', or the complement of the angle, 
 86° 32', which tliej measured on the 3d of June, 1765, 
 "formed by the radius from New Castle and the north 
 line." It does not appear that they ever actually meas- 
 ured the angle between the tangent line (or its pro- 
 longation), and the north line. That angle seems to 
 have been assumed upon the supposed accuracy of their 
 observation, noted in their survey book under date of 
 November 13 th, 1764, as follows, viz. : 
 
 " On measuring the angle formed by our last line and 
 the radius from New Castle, it was so near a right angle, 
 that on a mean from our lines, the above-mentioned 
 post [the tangent post fixed by their predecessors, and 
 by them marked -j^jj] is the true tangent point." 
 
 Now, the accuracy of that angle must have depended 
 upon the coincidence of the exterior termination of the 
 radius of twelve miles, with a perfectly straight line 
 prolonged from the court house at New Castle quite to 
 the tangent point. This radius was determined by the 
 simple method of measuring over the surface of the 
 ground with a surveyor's chain, for which purpose a 
 vista, or " visto^' as it was called by the surveyors in 
 those days, was opened through the forest as the work 
 progressed. We are surprised, at this day, that the 
 length of the radius should have been so correctly ob- 
 tained by such a method. There must have been, by 
 mere chance, a compensation of the errors incident to 
 
74 
 
 such a measurement over so great a distance. Very 
 small deviations from the true direction v^ould not, 
 however, produce much effect upon the distance, but 
 this is not true with regard to the angle which would 
 be formed between the tangent line and the radius, or 
 the north line and the radius. A slight deviation in the 
 direction of the radius at its termination, might affect, 
 in a material degree, the measure of either of these 
 angles, and we have reason to believe that the angle 
 measured by Messrs. Mason and Dixon, between the 
 tangent line and the radius from New Castle, which 
 ^^was so near a right angle;" and "the angle formed 
 by the radius from New Castle and the north line," 
 which they found to be = 86° 32', were both affected 
 by such an error. The tangent stone stands on low 
 ground, very near the margin of a morass, known by 
 the name of Cat Swamp. Looking from thence to the 
 east, the ground is pretty flat for half a mile ; then it 
 rises, by a rapid ascent, to the ridge running northward 
 from the summit of Chestnut Hill, distant one mile. 
 This ridge entirely shuts out the view of the whole 
 country to the east of it, from the tangent stone, and 
 must at least have limited the view of the radius, when 
 the angles it formed with the tangent and north lines 
 were measured by Messrs. Mason and Dixon. 
 
 These angles were, then, probably affected by what- 
 ever errors in direction may have arisen in running 
 eleven miles of that radius from New Castle. 
 
 Our own triangulation has given us the data for an 
 accurate determination of the angle formed by the tan- 
 
75 
 
 gent line, and the line drawn from the spire of the 
 court house at New Castle, to the point of intersection 
 at the tangent stone. 
 
 From it we have — 
 
 1. The angle at Iron Hill sub- 
 tended by the spires of the 
 court house and the church at 
 
 New Castle, =: 0° 26' 13" . 3 = « 
 
 2. The angle at New Castle court 
 house subtended by the sta- 
 tions on Iron Hill, and on the 
 
 arc west of the north line, = 5° 18' 31" = b 
 
 3. Value of the arc of 63,357.7 
 feet radius, included between 
 the tangent stone and the 
 trigonometrical station on the 
 curve, whose chord was twice 
 carefully measured and found 
 
 to be 753 feet, = 0° 40' 51" .S = c 
 
 4. Angle of deflection between 
 the tangent line and the north 
 line or chord of the arc of 
 
 boundary, = 3° 36' 06" = d 
 
 And here we are again indebted 
 to the coast survey records for 
 the azimuth of the line from 
 Iron Hill to New Castle church 
 spire, which is given to be, -__ 261° 28' 33". 9 = e 
 
76 
 
 Let the north-east angle formed 
 
 by the tangent line and the 
 
 radius drawn from New Castle 
 
 court house to the tano-ent 
 
 stone, = X 
 
 And the south-east angle, formed 
 
 by the same lines, =11/ 
 
 IliQn X = a+{h—c) + e+d—l^^° = %^° 08' 32". 9. 
 
 K-nd. 1/ =^m°—{a-^{b—c) + d+e) = m° 51' 27". 1. 
 
 So that the tangent line does not form a right angle 
 ■\vith the radius of twelve miles drawn from the spire 
 of New Castle court house to the point occupied by the 
 tangent stone. 
 
 The angle, at the tangent stone formed by these two 
 lines, differs 8' 32". 9 from a right angle. Now we find, 
 by computation, that the small deviation of forty-six 
 and one-half seconds in direction, or thirteen feet one 
 and one-half inch from a straig-ht line at the end of 
 eleven miles, in running this radius from New Castle 
 court house, would be sufficient to produce this differ- 
 ence of 8' 32" . 9 in the measurement of Messrs. Mason 
 and Dixon's angle at the tangent post, supposing their 
 view to the east to have been limited to the distance of 
 one mile, as it evidently must have been from the 
 nature of the ground. 
 
 Even this is indicative of a very small error in direc- 
 tion in tracing this radius, when we reflect that it was 
 prolonged through the forest by ranging staves or poles 
 in line, one beyond another, as the surveyors advanced 
 with their work, a method so inaccurate for tracing; a 
 
77 
 
 straight line that we are surprised it should have been 
 resorted to in so important an undertaking. This was 
 not, however, the work of Messrs. Mason and Dixon, 
 but of their predecessors, who were less versed in sci- 
 ence, and in the use of the higher order of geodetic 
 instruments than were Messrs. Mason and Dixon. 
 
 That the arc of the circle west of the due north line, 
 and the radius terminating at the tangent stone, were 
 traced and determined correspondent with one and the 
 same centre, by the surveyors under the agreement of 
 1760 and ourselves — that is to say, the spire of the 
 court house at New Castle, — is manifest from the follow- 
 ing evidence and authority. 
 
 The decree of Lord Hardwicke, of 1750, touches 
 these two points, and the position of Cape Henlopen, 
 in the following words, viz. : 
 
 " And two questions in particular having been raised 
 in America by the commissioners formerly appointed 
 by the defendant, the Lord Baltimore, and being now 
 made in this cause, namely, where the centre of the 
 circle, agreed by the said articles [alluding to the agree- 
 ment of 1732], to be drawn about the town of New 
 Castle therein mentioned, ought to be fixed, and whether 
 the said circle ought to be of a radius or semi-diameter 
 of twelve miles, or only a periphery of twelve miles; 
 and a third question being also made in this cause, 
 namely, at what place the Cape called in the said arti- 
 cles Cape Hinlopen is situated, his Lordship doth declare 
 that he is of opinion that according to the true intent 
 and construction of the said articles, the centre of the 
 
78 
 
 said circle ought to be fixed in the middle of the town 
 of New Castle, as near as the same can be computed, 
 and the said circle ought to be of a radius or semi- 
 diameter of twelve miles, and that Cape Hinlopen 
 ought to be deemed and taken to be situated at the 
 place where the same is laid down and described in the 
 map or plan annexed to the said articles, to be situated. 
 And, therefore, his Lordship doth further order and 
 decree that the said articles be carried into execution 
 accordingly," &c. &c. &c. 
 
 The above extract is taken from the old parchment, 
 bearing the original agreement of July 4th, 1760, with 
 the autograph signatures and the seals of Frederick 
 Lord Baltimore, and Thomas Penn and Richard Penn, 
 belonging to the Executive Department of the State of 
 Pennsylvania, which instrument contains this as well as 
 other recitals from the decree of 1750. 
 
 In the body of that agreement are also found the 
 following words, viz. : 
 
 " That the true length and extent of the said line 
 [alluding to the line across the peninsula from Cape 
 Henlopen], was, and is, and shall at all times hereafter 
 be esteemed, held, taken, and adjudged to be sixty-nine 
 miles and two hundred and ninety-eight perches, and 
 neither more or less. That, consequently, the exact 
 middle of such west line (from whence the other line 
 is to begin which is to run up the said peninsula, till it 
 makes a tangent to the western part of a circle, at the 
 distance of twelve English statute miles horizontally 
 measured from the Court House in the said town of 
 
79 
 
 New Castle), was, and is, and shall at all times forever 
 hereafter be esteemed, held, taken, and adjudged to be 
 at the exact distance of thirty-four of the said miles 
 and three hundred and nine perches, so measured west 
 from the aforesaid spot or place of beginning of the 
 said west line, as the same were so measured as afore- 
 said," &c. &c. &c. 
 
 Here we have an especial recognition of the Court 
 House in New Castle as the point fixed on for the centre 
 of the circle. 
 
 The proceedings of the commissioners appointed on 
 both sides, under the provisions of the agreement of 
 1760, and their instructions to the surveyors, are even 
 more explicit upon this point. 
 
 In the record of those proceedings, under the date 
 of November 7th, 1761, we find the following: 
 
 '' Saturday, the 1th of November, 1761. 
 " Nine o'clock, A. M. 
 
 " The commissioners met according to adjournment. 
 
 " Present as on yesterday. 
 
 " The commissioners, having made their calculation, 
 find that the tangent will, at the middle point, make an 
 angle of three degrees thirty-two minutes and five 
 seconds with the meridian line lately run by the sur- 
 veyors, and they agree that a radius of twelve miles, 
 horizontal measure, shall be run from the centre of the 
 Court House in New Castle, northwards of the line of 
 intersection lately run from that place, so as to make 
 an angle therewith of nineteen degrees three minutes 
 
80 
 
 and fifty-five seconds, which radius the commissioners 
 find, by the calculations they have made, will terminate 
 in the tangent point in the periphery of the circle. 
 
 " Then the commissioners agreed to give the survey- 
 ors the following instructions, viz. : — 
 
 " Gentlemen : — You are to run a straight line of the 
 length of twelve English statute miles, horizontal meas- 
 ure, or as nearly horizontal as you can, from the centre 
 of the Court House in New Castle, in such direction as 
 to make an angle of nineteen degrees three minutes 
 and fifty-five seconds northwards with the line of inter- 
 section lately run by you from the centre of the said 
 Court House ; and at the end of such twelve mile line 
 you are to set up and secure a post or stone, at the same 
 time making such visible marks near it, as may enable 
 jou. hereafter to discover and determine its place, in 
 case it should be destroyed or removed. And in order 
 to preserve the direction of the said line, you are, also, 
 at the end of six, ten, and eleven miles from New Castle, 
 and at the distance of twenty perches eastward of the 
 end of such twelve mile line, to set up other posts in 
 the said line. November 7th, 1761. 
 
 J. PJDOUT, JAMES HAMILTON, 
 
 JNO. LEEDS, RICHARD PETERS, 
 
 JOHN BARCLAY, BENJAMIN CHEW, 
 
 WM. COLEMAN." 
 
 " To Messrs. Thomas Garnett, Jonathan Hall, John Lukens and 
 Archibald McClean, Surveyors. 
 
81 
 
 " The commissioners adjourned to the first day of 
 April next, at which time they agreed to meet again at 
 New Castle. 
 
 J. RIDOUT, JAMES HAMILTON, 
 
 JNO. LEEDS, RICHARD PETERS, 
 
 JOHN BARCLAY, BENJAMIN CHEW, 
 
 WM. COLEMAN." 
 
 We conclude the evidence on this point by quoting 
 from the note book of the surveyors, who, in the year 
 1761, traced the radius and fixed the post marked ^jj 
 at its western extremity. It will be remembered that 
 this is the post which the commissioners, in their pro- 
 ceedings of the 24th of November, 1764, declared, 
 " shall be and be deemed and accounted to be the true 
 tangent point, and that the surveyors shall proceed to 
 run the north line and such part of the circle as falls to 
 the westward of the said line, according to the articles, 
 from the said point," &e. &c. 
 
 The surveyors' records are as follows, viz. : 
 
 " Saturday, November 7, 1761. 
 " In pursuance of the last instructions, and also other 
 directions from the commissioners, we this day went to 
 the post near Joseph Tatloe's house, and from thence 
 extended the direction of the line, on which the base 
 was measured for computing the distance from said post 
 to the spire on New Castle Court House, to the distance 
 of twenty-four chains sixty-three links and three-tenths 
 of a link, thereby subtending an angle of 19° 3' 55" at 
 6 
 
the spire aforesaid, that being the angle which by the 
 said last instructions we were required to make with 
 the line of intersection :* which said distance terminated 
 in a point fixed on a white oak post well secured in the 
 ground in the aforesaid direction, and found, by calcu- 
 lation, to be seventy-five chains thirty-one links and 
 seventy-six hundredths link distant from the spire afore- 
 said, on the twelve mile line therein directed to be run. 
 
 JNO. LUKENS, JONA. HALL." 
 
 ARD. McCLEAN, 
 
 " November 8, Sunday, 1761." 
 
 " NoTEMBER 9, 1761, Monday. 
 " After ingaging sundry axemen this morning, Mr. 
 Thomas Garnett, one of the surveyors on the behalf of 
 his Lordship, having resolved to go home, and Jonathan 
 Hall receiving advice that his wife was sick, thought 
 proper to go home a few days, and there being none 
 other here to act on the part of his Lordship, in running 
 and measuring the line, which, by instructions of the 
 seventh instant, we were directed to run and measure, 
 we were, therefore, under the disagreeable necessity 
 (notwithstanding we have divers persons in pay), to 
 adjourn to the sixteenth of this month, at which time 
 we agree to meet at New Castle, in order to run and 
 measure the line as instructed. 
 
 JNO. LUKENS, JONA. HALL." 
 
 ARD. McCLEAN, 
 
 * Alluding to the first experimental line run from the court house to intei'sect a 
 due north line, which was traced up the peninsula, from the " middle point " of 
 the line run west from Cape Henlopen. J. D. G. 
 
83 
 
 " Monday, November 16, 1761. 
 " This morning early we met at New Castle, accord- 
 ing to adjournment, and went to the post, which, by the 
 direction of the commissioners, we set in the ground on 
 the seventh instant, at the distance of seventy-five 
 chains thirty-one links seventy-six hundredths of a link, 
 by computation from the spire of the court house of 
 New Castle, and, after opening a visto toward the said 
 spire from the point mentioned to be fixed in said post, 
 we extended a line westward, in the direction of said 
 spire and point, four chains sixty-eight links twenty-four 
 hundredths of a link to a squared white oak post marked 
 J ; which said post is found by the aforesaid computed 
 and measured distances, to be one mile distant from the 
 spire on said court house. 
 
 JNO. LUKENS, JONA. HALL." 
 
 ARD. McCLEAN, 
 
 After detailing each day's work, in the prolongation 
 and measurement of this radial line, the surveyors de- 
 scribe its completion on the twenty-eighth of November, 
 and its re-measurement between that date and the sec- 
 ond of December, as follows, viz. : 
 
 " Saturday, Novemher 28, 1761. 
 
 " Proceeded with the line sixty-three chains, where 
 we fixed and secured firmly in the ground in the mea- 
 dow, late Lewis Thomas's, a squared white oak post 
 marked -^j^ ; the said measure ending in a point fixed 
 thereon, which said post, we are of opinion, is twelve 
 
English statute mileSj horizontal measure, distant from 
 the spire of the court house in New Castle, that being 
 the distance which, by our instructions, we were enjoin- 
 ed to extend the said line, during the measure of which 
 distance we kept the account in four-perch chains, 
 though where hills intervened, the measure was per- 
 formed by instruments, before prepared for rendering 
 the same horizontal, and, where level, the same was 
 •.taken by a two-perch chain, which we frequently and 
 carefully measured ; and, after fixing the said twelve- 
 mile post, we took the courses and distances from thence 
 to the several trees, as expressed on the next page,* 
 thereby to determine its place, in case it should be 
 destroyed or removed ; afterward we fixed a white oak 
 post in the said direction, at the distance of twenty 
 perches to the eastward of the said post ; which done, 
 we agreed to begin at the said twelve mile post and re- 
 -measure the line toward New Castle superficially, least 
 a mistake should have been committed from the differ- 
 ent modes we were obliged to pursue, or take, in order 
 to make the measure horizontal, which re-measure we 
 continued to the ten mile post, and left off. Afterward 
 settled with and dismissed sundry of the laborers. 
 
 JNO. LUKENS, JOHN F. A. PRIGGS, 
 ARD. McCLEAN, JONA. HALL." 
 
 " November 29, Sunday. ^^ 
 
 * The next page of tlie old surveyor's book contains the diagram referred to. 
 
 J. D. G. 
 
85 
 
 " Monday, November 30, 1761. 
 
 " Continued the re-measure of the Ime (as on the 
 twenty-eighth instant), from the ten mile post to the 
 two mile post, where night came on. 
 
 JNO. LUKENS, JOHN F. A. PRIGGS, 
 ARD. McCLBAN, JONA. HALL." 
 
 " Tuesday, Decemher 1, 1761. 
 " Continued the re-measure as before from the two 
 mile post to the post which we set up on the seventh 
 ultimo, from which the direction of the line was taken, 
 and, from the proportional agreement between the 
 superficial and horizontal measure, find that no mistake 
 hath been committed. 
 
 " Settled with, and dismissed, the chain-carriers, and 
 all the other hands except the steward and wagoner, 
 then rode to Wilmington, there to take account of and 
 deposit the stores for the winter season. 
 
 JNO. LUKENS, JOHN F. A. PRIGGS, 
 ARD. McCLBAN, JONA. HALL." 
 
 "Wednesday, December 1, 1761. 
 
 " This day took account of the stores ; stored them 
 in Wilmington, in the care of John Stapler, Esq. ; 
 settled sundry accounts, dismissed the steward and the 
 wagoner. 
 
 JNO. LUKENS, JOHN F. A PRIGGS, 
 ARD. McCLEAN, JONA. HALL." 
 
From tlie foregoing authorities, no doubt whatever 
 can exist that the point agreed on and used as the cen- 
 tre of the circle of twelve miles radius by the commis- 
 sioners and surveyors of Lord Baltimore, and Thomas 
 and Richard Penn, was one and the same as that in 
 reference to which the arc of the circle west of the due 
 north line, and the radius terminating at the tangent 
 stone, were traced and determined by us in our recent 
 survey. 
 
 The discrepancies, then, which have been shown be- 
 tween our work and theirs, in regard to this arc and the 
 angle formed between the radius and the peninsular or 
 tangent line, at the tangent stone, cannot be attributed 
 to any difference in our positions respecting the centre 
 of this circle. 
 
 The radius run out by the surveyors in 1761, indi- 
 cated by a line drawn from the spire of the court house 
 in New Castle, to the present position of the tangent 
 stone, should be revolved about the centre of its circle 
 (the spire aforesaid), through an arc of 8 minutes and 
 34 seconds and one-tenth of a second to the south, and 
 then produced two feet four inches westward, and the 
 line called the tangent line, should be revolved west- 
 ward about its southern extremity, at the "Middle 
 Point" of the Cape Henlopen line, through the inappre- 
 ciable angle of one second and two-tenths of a second, 
 and then these two lines would meet at right angles, at 
 the distance of 157.6 feet southward from the present 
 position of the tangent stone. 
 
 The slight variation thus required in the azimuth of 
 
87 
 
 the tangent line, proves the surprising accuracy of its 
 direction as determined by Messrs. Mason and Dixon, 
 and how truly it divided the Provinces, in accordance 
 with the articles of the ancient agreement, as far as it 
 extended, which is given by Mason and Dixon in their 
 notes of survey, to be 81 miles 78 chains and 31 links ; 
 or, 17.2 yards less than 82 miles. 
 
 It is equally surprising that there should have been 
 so great an error in their elements for marking out the 
 arc of the circle west of the north line, and in the length 
 of their chord, which they computed to be 116 chains 
 
 and 5 links, or 7,659.3 feet. 
 
 And which we find to be, as actually 
 marked by the tangent and intersec- 
 tion stones, 7,743 " 
 
 But which, according to our computa- 
 tions, should have been 7,960.6 " 
 
 And should have begun at a point 157.6 feet southward 
 of the present position of the tangent stone, and have 
 ended at a point 143 . 7 feet north of the present position 
 of the stone set by Mason and Dixon, and the commis- 
 sioners of their day, to mark its termination, and consti- 
 tuting now the point of junction of the three States. 
 
 The origin of this error has, we think, been satisfac- 
 torily discovered. 
 
 It is our opinion that the stones on the arc, west of 
 the north line, stand as originally placed. Of this we 
 have evidence, conclusive enough, from the lengths of 
 our measured ordinates of that arc, compared with the 
 3d, 6th and 9th in the table of Mason and Dixon, copied 
 at page 72. 
 
88 
 
 Tim foUouing is a eom^Mvison of our measurements, with 
 theirs, for this arc. 
 
 According to Mason and Dixon's survej'' 
 made in 1765. 
 
 According to our measurements on the 
 ground in 1849. 
 
 
 Distances on chord 
 
 from tangent stone, 
 
 in feet. 
 
 Lengths of or- 
 dinates, in feet. 
 
 Distances on chord 
 
 from tangent stone, 
 
 in feet. 
 
 Lengths of ordi- 
 nates, in feet. 
 
 1 
 
 2 
 8 
 
 1,851.3 
 3,831.3 
 5,811.3 
 
 84.8 
 
 115.8 
 
 84.8 
 
 1,855.3 
 
 3,836.7 
 
 5,872.7 
 
 85.4 
 115.6 
 
 84 
 
 We can make no comparison with the marked stone 
 on the arc intervening between the 2d and 3d of the 
 above table, and which was intended to be put at the 
 meridian distance of one mile from the tangent stone, 
 for the reason that Mason and Dixon do not give the 
 length of their ordinate for that one. 
 
 We found it, however, to be 101.4 feet perpendicular 
 from the chord to the west, and we find, by computing 
 its place from the elements assumed by Mason and 
 Dixon for marking this arc, that it would be 99.4 feet. 
 
 The foregoing table shows conclusively that the tan- 
 gent stone could never have been moved from its ori- 
 ginal position, for our first and second distances from it 
 on the chord, or north line, correspond almost exactly 
 with those given by Mason and Dixon, quite within the 
 probable errors of careful chaining at least. The dis- 
 crepancy in our distances to the third ordinate is no 
 doubt owing to an error in the count of one chain 
 (66 feet) on their part, for our distance was tested by 
 three measurements. 
 
89 
 
 There is no doubt that that stone and the intersection 
 stone remain at this day in the positions given to them 
 by the commissioners and surveyors in 1765. 
 
 In addition to the above evidence, we have that 
 which arises from the fact that they both now stand 
 upon their proper lines of direction, which would 
 scarcely have been preserved had they been moved by 
 mischievous interference. The tangent stone stands 
 now precisely upon the same right line, with the three 
 monuments to the southward of it on the tangent line, 
 and the intersection stone stands as truly on the north 
 line. The error in the distance intended to be given 
 them apart by Messrs. Mason and Dixon (which acci- 
 dental distance we actually found to be nearer the 
 truth than their computed distance), was probably one 
 of miscount in their chain measurement, as was also 
 the error of one hundred and thirty* feet in the merid- 
 ian distance of the marked stone on the arc from the 
 tangent stone, which they state to be one mile. 
 
 Those who believed that the tangent stone had been 
 disturbed in its position because of the fragments of 
 stone of a similar character which, for some time, lay 
 strewed at its base, were not carried so far back by tra- 
 dition as the period when this point was marked by two 
 similar stones, engraved alike with the arms of the pro- 
 prietaries, and placed side by side, " the better to dis- 
 tinguish and ascertain the tangent point," as will appear, 
 
 =* This error was probably caused by a miscount of two chains which would be 
 equal to one hundred and thirty-two feet. J. D. G. 
 
90 
 
 was done, by reference to the records of the commis- 
 sioners imder the dates of June 18th, 1765, and No- 
 vember 20th, 1766, given in the preceding extracts 
 and briefs of their proceedings. 
 
 The fragments which we were told of while engaged 
 in the reconnoissances, were the remains, no doubt, of 
 the missing companion of the one we found a little 
 inclined in posture, but firmly planted in the groimd. 
 When it was taken up, for the purpose of placing the 
 new stone, which will presently be noticed, it was un- 
 broken and perfect in its form. 
 
 Had Messrs. Mason and Dixon adopted the method 
 of tracing the arc by deflecting from their tangent line 
 (which is so true in its direction), and then from chord 
 to chord of a constant length, to find points on the cir- 
 cumference of that arc, it would not have been affected 
 by the want of perpendicularity in the assumed direc- 
 tion of the radius to the tangent. They would, by this 
 method, have described the true arc, independent of 
 any reference to the radius, exce|)t alone as to its 
 length, and they would have intersected the north line 
 by the curve at precisely the distance from the tan- 
 gent stone computed by us, that is to say, at 7960.6 
 feet from it, and 217.6 feet in advance of its present 
 position. 
 
 The error in their curve is not one of moment, as 
 regards extent of territory, as it abstracts from Dela- 
 ware and gives to Maryland only about ItVo of an 
 acre. The versed sine of their arc is 115.8 feet, and 
 that of the arc they should have traced is 125.3 feet. 
 
91 
 
 Although their measured distances are found to be 
 affected by many errors, incident always to measure- 
 ments of great extent with the chain, yet the direc- 
 tions of their lines are correct, and as the only distance 
 included in their portion of the survey, and specified 
 as an element in the boundary, — namely, the fifteen 
 miles south of the parallel of the most southern limits 
 
 J. 
 
 of the City of Philadelphia — was, after measurement 
 with the chain, corrected by very accurate observations 
 for the corresponding difference of latitude, the abso- 
 lute division of territory between the then Provinces 
 was effected, from the south extremity of the tangent 
 line to the north extremity of the north line, on the 
 whole, with great accuracy. Their long west line or 
 parallel of latitude we have had no occasion to test, 
 except for a short distance, but the great care with 
 which their astronomical observations, contained in the 
 old manuscripts at Annapolis, were made, leaves no 
 doubt of the accuracy of that part of their work. 
 
 These observations, together with the records of the 
 proceedings of the several joint commissions charged 
 with the division of the then Provinces in question, 
 will be more fully alluded to in a report to Col. Abert, 
 Chief of the Corps of Topographical Engineers, and 
 they will, I hope, be rescued from their long slumber 
 in quiet obscurity, and be laid before the world in a 
 printed form. 
 
 The conclusion having been arrived at, that none of 
 these monuments, found on the curve, at the tangent 
 point and at the intersection point, had been disturbed 
 
92 
 
 in their original positions, which was ratified by your 
 Board, the obUgation to consider them true marks of 
 boundary is imposed by the declaration to that effect 
 by the commissioners acting on behalf of their respect- 
 ive constituents, Lord Baltimore, and Thomas and Rich- 
 ard Penn, fully expressed on the records of their pro- 
 ceedings. 
 
 o 
 
 Accordingly, by your directions, in addition to the 
 new monument fixed at the north-east corner of Mary- 
 land, as already mentioned, the following were also 
 erected at the tangent point, at the intersection point, 
 or junction of the three States, and on the meridian 
 of the curve, viz. : 
 
 At the tangent point, a post of cut granite, 6 feet 
 long, and squaring 18 by 15 inches, was inserted 41 
 feet of its length in the ground, on the north side of 
 and touching the old stone bearing the engraved arms, 
 which remains in its old position. On the north side 
 of the new stone is graved, in deep cut letters, the 
 word TANGENT, with the date 1849- 
 
 At the point of junction of the three States, a trian- 
 gular prismatic post of cut granite, 18 inches wide on 
 each side, and 7 feet long, was inserted 4^ feet of its 
 length into the ground. It occupies the exact spot on 
 which the old unmarked stone was found. It is marked 
 with the letters M, P and D, on the sides facing respect- 
 ively towards the States of Maryland, Pennsylvania, 
 and Delaware. On the north side, below the letter P, 
 are the names of the commissioners, in deep cut let- 
 ters, namely : " H. G. S. KEY, of Md., J. P. EYRE, of 
 
93 
 
 Pa., G. R KIDDLE, of Del., Commissioiners," with the 
 date 184fl. This boundary stone stands upon land 
 now belonging to Wm. Johnson. The old unmarked 
 stone was buried, lying in a prostrate or horizontal posi- 
 tion, just below the surface of the ground, on the north 
 side of and central with the new stone. 
 
 At the meridian, or middle point of the arc, corres- 
 ponding to the length of the chord, as we actually found 
 it, and at the distance of 118.4 feet perpendicular from 
 the middle point of said chord, a post of cut granite, 
 6 feet long, was inserted li- feet of its length into the 
 ground. This stone squares 17 by 14 inches. It is 
 rounded on the west side to indicate that it is on the 
 curve, and on the east side the date 1819 is marked in 
 deep cut figures. 
 
 The circular boundary between Pennsjdvania and 
 Delaware, from the point of junction of the three States 
 to the river Delaware being yet unmarked, and a num- 
 ber of citizens residino; near this common border beinai; 
 in doubt, and anxious to know, to which State they 
 belong, at your suggestion the survey was conducted 
 with such precision as to enable us to describe that 
 boundary correctly, as will appear upon our map, for a 
 distance of about 31 miles north-eastward from the 
 junction. 
 
 We have determined the distance by computation, at 
 which a due east line from the north-east corner of 
 Maryland will cut that circular boundary, and find it to 
 be 4036 feet, or . 764 of a mile. We have also com- 
 puted the angle with the meridian at the said north-east 
 
94 
 
 corner, made by a line drawn from tlience to the spire 
 of the court house at New Castle, and find it to be 
 70° 20' 45" east of south. At the distance of 3,786 feet, 
 measured on the said line from the aforesaid north-east 
 corner, this line will intersect the circular boundary. 
 
 The want of a proper demarcation of the boundaries 
 between States is always a source of great inconve- 
 nience, and often of trouble to the border inhabitants; 
 and it is worthy of remark, that as our survey pro- 
 gressed, and while making the necessary offsets to 
 houses on the east of the north line, we discovered that 
 there was an impression among many, that the boundary 
 of Delaware extended up to the north line, from the 
 junction to the north-east corner of Maryland. 
 
 Mr. W. Smith, a gentleman who has once served as a 
 member of the Legislature of Delaware, resides a full 
 half mile within the State of Pennsylvania, measured 
 in the shortest direction from his dwelling-house to the 
 circular boundary. 
 
 We find, also, by careful measurement, that Christiana 
 church is in Pennsylvania, full one hundred yards west 
 of the circular boundary. The dwelling-houses of 
 Messrs. J. Jones, Thomas Gibson, Thomas Steel, and J. 
 McCowan, — heretofore supposed to be in Delaware — are 
 all within the bounds of Pennsylvania, according to our 
 trace of the circle from computed elements. 
 
 I take great pleasure in acknowledging here the 
 valuable aid rendered, in this survey, by my assistants, 
 Lt. George Thorn, of the Topographical Engineers, and 
 Mr. Charles Radziminski. 
 
95 
 
 The former was obliged, by his duties in the office of 
 the North-Eastern Boundary, to return to Washington 
 on the 24th of November. He joined us, however, 
 again, on the 29th of January, and participated in the 
 completion of the field-work, on the 6th of February, 
 at a time when, owing to the delays which the almost 
 continued stormy and cloudy weather in January had 
 produced, his aid was very important. 
 
 Mr. Eadziminski remained in the field from the begin- 
 ning to the end of the work, and used every exertion 
 to forward it. Mr. Derrick, our junior assistant, did the 
 same. They lost not a day that could be appropriated 
 to the out-door work ; and often, when the weather was 
 unpromising, they would go out, in order to be ready to 
 observe angles, &c., if it should clear, and w^ould return, 
 drenched with rain, or covered with sleet, during the 
 cold weather of December and Januar}^ never regard- 
 ing their personal comfort, when the work could be 
 forwarded by exposing themselves. 
 
 I herewith present three finished maps, one for each 
 of your respective States, constructed from our surveys, 
 and duly certified.* 
 
 All which is respectfully submitted. 
 
 J. D. GRAHAM. 
 
 * These maps are on a scale of 4 inches to 1 mile, or ts.V?^* 
 
 J. D. G. 
 
T)#t.2S.if?; 
 
■■<^ 
 
 My 
 
BBtS?' 
 
 
XI