ik1 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924073796090 3 1924 073 796 090 H5H55SIQJ WB mSSSSESEEl 'I ESTABLISHED ;;iiiiiiiiiui!i:iiiii!i{[iiiiii;iiiiiiiii»:{i»!iiiHiiiiBiiiniiii!ii{iii{iii i| |: Id !3 E5H5E5H5H5H5 □ ES HggS 3 ^i i iiiiiiiiiniiiiii!ii!H iiiiiiii[itiitiiini;ii:iiiiiiiiiiiii miitii <^^ S2^ifg:Cv5i^ GATALOGUE of Physical Apparatus, Instruments and Utensiles foi Universities, Colleges and Superior Schools by 0. ieilaiit Marquart's Stoie of Chemical Utensiles > . .V C^. . ^^ BONN, on the Rhine. 5*3 '^^ Kl □ m feJiVJII |D|5a5H5S555g5H555H5H5B555H5B5E5E5H5H5H5a5E5Bm[51^A^^ I I iiiiniiiiniiiiiiHiiHiiiiiiiii II i>ri II II 111 III nil iin 1 1 m i niii ehi i i J I I L x II I 1 1 iiiLi iiiu II iiiiiiiMiiiiiiwiiiniiiiiii [Iglggsasa 96 LIBEETT & 41 ITEW CHURCH ST. -/jnC^.t^^d.^ y)jiAM::Xp:iA'^^^^{ New York, February 1886. .&4i^<^-^-^^ • M Deab Sie : As the college year is about to close, and orders for Physical, Chemical and Liiboratory Supplies are being made out, we take the opportunity of offering our services for the Importation, free of duty, of Chemicals, Chemical and Physical Ap- paratus', Collections of Mineials, Models of Czysials, or any articles that colleges and schools lire privileged to import free of duty for educational purposes, in conformity to the regulations of the United States Treasury Department. We have for several years cultivated this special branch of our business, and now per- fected its working in every detail. For the information of customers and parties whose patronage we have not heretofore enjoyed, we beg to state that : 1 - We sell all articles without any advance over the published catalogues, so that the cost price to our customers ^ ill in no instance be higher in buying through us than it would be if they ordered direct, and if any particular manufacturer's goods are desired, we order them as directed. 2 — If no manufacturer is designated, we select from the best sources, especially from the houses which we represent here as their sole agents, and guarantee the correctness and the quality of goods in every instance. 3 - As we have our own resident buyer in Germany, to whom all smaller packages are f.irected, and by whom they are forwarded in larger lots to the steamship lines in either Hamburg or Kotterdam, we are in this way enabled to save a large amount of expense to our cus tomers, and land the goods at the port of New York at lower figures than could be obtained for any single order forwarded separately. 4 - Manufacturers as a class, especially tho.se of glassware and finer apparatus', carry but a limited stock on hand, and work mostly after obtaining orders, which are filled in rotation. For this reason we cannot recommend too strongly the advisability of - Placing the order for at least the larger portion of the articles required at the earliest possible date; additions can be then obtained with less delay; we shall be pleased to sup- ply ruled blanks for orders. 6 — Whenever our customers desire to receive shipments through other ports of entry than New York (on account of delays formerly experienced here), we are prepared to ac- commodate them, but think the statement justified that under the new Custom House changes no unnecessary detension of entries, beyond actual necessity, need be anticipated 7 — We solicit your correspondence on this subject, and will by permission refer you to many Professors of the American Colleges of the highest standing, for whom we have imported goods during several seasons, to their entire satisfaction. Very respectfully r. ALFKED KEIOHAEDT & CO., IMPOBTEES OF FINE CHEMICALS, CHEMICAL & PHYSICAL APPARATUS'. CATALOGUE of Physical Apparatus, Instruments and Utensiles for Universities, Colleges and Superior Schools by ]VIarq-aart's Store of Cheraioal TJtensiles BONN on the Rhine. CONTENTS. Page Preface HI I. Mechanics 1 II. Theory of Undulation 47 III. Acoustics 49 IV. Optics 60 V. Heat ' 88 VI. Magnetism 98 VII. Electricity 101 VIII. Meteorology 130 Set 1 136 „ II 137 „ HI 138 „ IV 140 Index 143 he following books have been utilized for this catalogue: Muller-Pouillet, Lehrbuch der Physik, VIII. edition. 1878- 81. Published by Friedrich Vieweg & Sohn, Brunswick. A. Weinhold, Physikalische Demonstrationen, 1881. Published by Quandt & Haendel, Leipsic. Frick, Die physikalische Technik, 5. edition 1876 and 4 edition 1872. Published by Friedrich Vieweg & Sohn, Brunswick. Krumme, Lehrbuch der Physik fiir hohere Schulen. Published by Grothe, Berlin. Krebs, Die Physik im Dienste der Wissenschaft , der Kunst und des practischen Lebens. Published by F. Enke, Stuttgart. Carl's Repertorium der Physik. Published by R. Oldenbourg, Mflnchen. Eisenlohr, Lehrbuch der Physik, X. edition. Published by J. Engel- horn, Stuttgart. Poggendorf's Annalen der Physik und Chemie. Published by J. A. Barth, Leipsic. Zeitschrift fiir Instrumentenkunde 1881. Published by Julius Springer, Berlin. Humboldt, Monatsschrift fiir die gesammten Naturwisseuschafteu. Published by F. Enke, Stuttgart. Report on the Scientific Instruments on the Berlin Industrial Exhibition in the year 1879. Published by Julius Spinger, Berlin H. W. Vogel, Practische Spectralanalyse irdischer Stoffe. Published by Beck, Nordliugen. Schelleu, published by Dumont-Schauberg, Cologne. IV Journal de Physique, published by the Bureau du Journal de Physique, Paris. Bericht der deutschen chemischen Gesellschaft. Published by A. W. Schade, Berlin. Each apparatus is carefully tested before despatching. I fully warrant for the good quality of all supplied ajiparatus. Also all other chemical and philosophical apparatus, which are not mentioned in this catalogue, will be furnished. C. Gerhardt Marquart's Store of Chemical Utensiles BONN. I. Mechanics. A. statics and Dynamics. Mk. Pf. 1. Apparatus for showing the parallelogram of forces. — Frick, Fig. 91, en- tirely of metal, upon tripod-stand and with adjusting screws .... 25. — 2. — do. upon round stand, without adjusting screws 11. 50 3. — do. Bertram's, entirely of metal Bpon tripod-stand with adjusting screws 30. 50 A detailed description of this apparatus will be sent on demand. 4. — 5. — G. 7. No. 4. No 5. do. same without adjusting screws 27. 50 With the apparatus 1—4 a certain parallelogram, having been determined, weights are suspended to the ends of the strap, these weights will be proportionate to the sides or the diagonal of the parallelogram. new construction, entirely of metal, with stand on a board 30. 50 Any weights having been suspended to the ends of the strap, the parallelogram will form itself spontaneously and in such a manner, that its sides or diagonal will bo proportionate to the suspended weights. do. simple pattern — MuUer-Pouillet I. Fig. 17 — it consists of two rolls sliding on vertical rods, straps and weights 13. 50 do. same, of wood, quite simple 8. 50 1 C. Gerhardt, Marquart's Lager chemisclier Utensilien, Bonn. Mk. Pf. Apparatus for showing the parallelogram of forces — Varignon's Table — see Krumme, Fig.. 9 49. 50 The apparatus G — 8 show only the direction of traction. The proportions of such to the side and diagonal of any given parallelo- gram has first to be determined. 10. n. 12. 13. 14. 15. 16. 17. 18. No. 9. — do. Sprockhoff's, illustrating at the same time the steering of ships. — A detailed description of this apparatus on application 53. — — do. Kreb's, Fig. 24, consisting of two apparatus, one of which explains, how two lateral forces are combined to one resulting force, the other how one force can be devided into two lateral forces 66. — Joint-Lever. — Frick, Fig. 94 — upon tripod-stand with adjusting screws 27. 60 — do. without adjusting screws 20. Jolnt-Lever-Press 40 — Diagonal-Machine — Weinhold, Fig. 59 — with ivory-ball 16. 50 — do. same, larger 33 — do. - Krebs, Fig. 25 — with electromagnetic ratch 49. 50 Eberhardt's Engine for the demonstration of a combined movement produced by the continuous action of forces 13. 50 — do. — Frick, Fig. 97 — Model of the so-called flights of theatres . 22. — C. Gerhardt, Marquart's Lager chemiscber Utensilien, Bonn. Mk. Pf 19. Apparatus for the demonstration of the Principles of the inclined plane, simplest model — Frick, Fig. 102 16. 50 20. — do. Bertram's, entirely of metal, with scales for the length, the base, and the heigth of the inclined plane, also with sextant. — Fiaest making, the points in agate-caps 93. 50 21. — do. same as 20, but without sextant 82. 50 22. — do. same as 20, with sextant but without adjusting screws, the points in steel-caps 59. 50 23 — do. same as 22, but without sextant — Miiller-Pouillet I. Fig. 640 . 53. — The construction of the apparatus 20 to 23 allows the moving force to act parallel and horizontal to the inclined plane. 24. — do. Weinhold, Fig. 63, serves at the same time for measuring the pressure of the charge upon the inclined plane GO. 50 25. - Krebs, Fig. 82 53. — With this apparatus the moving force and the pressure of the charge upon the way are not measured by weights, but by spring- balances. J 1:15 . ^&=siHO=^^=^--=' No. 21. No. 28. 26. Mechanism for explaining the screw — Frick, Fig. 105 and 106 — the screw with one or several turns 2. 25 27. — Pattern of a screw with sharp or flat turn and with profile of a box — made of wood 2. 75 28. Apparatus for the demonstration of the action of a screw, entirely of metal, with a screw 33. — 29. — do. vrith two screws of different grades 40. — This modification of MuUer's Apparatus (Frick, Fig. 107) allows to measure much more exactly and also of using screws of different grades. Mechanisme for explaining the various applications of a screw — made of metal. 30. — a fixed screw-box with a turning and progressive worm 16. 50 31. — a turning worm with a progressive box 27. 50 32. — a fixed worm with a turning and progressive box 16. 50 33. — a turning box with a progressive worm 27. 50 34. — these 4 apparatus 30 to 33 together 77. — 35. Model of a Screw-Press of metal. MuUer-Pouillet I. Fig. 45 27. 50 36. — do. more simple and of wood 16. 50 37. Model of a Hunter's Screw-Press, of metal 40. — 1* ■1 0. (Jorluinit, Miuqiiutt's Latjor clioniiscluM- IMt'iisilioii, Homi. Mk. I'f, .... -Ji!. . , , . 10. — , . S. V.'.'( .... UD. ■1'2. Apparatus for denioiistrnting the principles of tlio Worige. — Kiirk, li'in. 113 i;>. fiO . . . ,'i',l. .M) 38. Model of an Arohlmedio Screw. - Krick, Ki^. 110 ., . 39. — do. siiiiploi', tlio Mi'i'ow coMsist.s ol' a wound );lass tulio 40. Screw and Wlieel, of wood 41. — do. of motsil 43. — do. now oonslnu'tioii witii wod^o soo illiustrulioii No. 43 Nil. 40. 44. — do. witli 2 dilToii'iit. wodgos (It;. With tliia apparatus tlio pro|H)itioiuility of l.lio I'ditch iidiiiK upou tlio NidoH and llio liuok ol' tlio woilf^(\ iimy lio oxui'tl)' dotoi'iiuncd. 4.'). — do. Rii4itor\s 'j-J. 1 m No 'i.'i. (>. Movable or flxe [| Pulleys. with 1 pulloy with 2 puiloyH next or abovo ouch otiior III' wood of braas 2 75 4. — 3. -2r> T). 50 u i'!lUi l:'l Nil. lY. with 3 piiiioyH iioxt III' ;ilioV(i Olioll (llhlT 4. .'lO 7. — 47. Weights for Pulleys: 1 Sot containinK, (i holdoin of oiio ounce, 10 ol' '/a ounce, 2 of ''/„ ounce, 2 of 2 oumcoh, I of 4 oiimcch the wci|..|itH are of brass and contiiinod in a box 48. — VVcip;lit,4 of load without bo.\ 49. Scales for Pulleys 20, U. 1. 7r. C. Gerlianlt, Marquart's Lager chemischer Utensilicn, Bonn. Mk. Pf, 50. Support for Pulleys — upon wood-box 33. — 61. — do. upon iron-stand 16. 50 52. — do. same, but smaller 11. 50 53. — Simple Support for Pulleys, scales etc. — with a movable horizoutal arm to be screwed to a table 8. 25 Pulleys 54. — four different with brass-pulleys and Stand No. 52 49. 50 55. — do. without stand 40. — 5i3. — four different with wood pulleys and Support No. 52 33. — 57. — do. without Support 22. — 58. — six different pulleys with brass-rolls and Support No. 50 77. — 59. — do. with Support No. 51 64. — 60. — without Support 53. — 61. — six different pulleys with wood-rolls and Support No. 51 44. — 62. — do. without Support 30. 50 G3. — Differential-Pulley of metal upon Support 33. — 20. - 8. 25 16. 50 26. 50 49. 50 27. 50 g4. _ do. of wood upon Stand 65. Lever-Apparatus — Frick, Fig. 130 G6. — do. — Frick, Fig. 129 67. - do. - Frick, Fig. 125 G8. — do. with movable axis 69. — do. Bertram's, with tongue to screw on or off, entirely of metal . 70. do. new construction, on a case with drawer 55. C. Gorlianlt, MniqiKiit's l.;igor cluMnisclior lUi'iisilioii, Hoim. Lever -Apparatus Mk. I'l'. 71. - do. T.^^i'liccliowiti'irs. -- r:irr.'< Ki'iHMt. \11 |ig. lori -■ Omiiliiiu'd witli a nieolu\nisiii to donioiistrato tlio parnllclogrrtin of I'ori'ivs SS, No. rill. 11. No. 711i. 7 la. Mechanic Powers, sz. draw-lionm, oiullo.s.s .scow, wlu'i'l and pinion, n'(. !'(» 711'.— do. samo, mado of wood X\. -i c^-^lf No 70. Nu. 77. 72. 73. 74. 7o. 7(i. 77. 78. 7S). 80. 81. 82. 83. Wheel on the axle — of nidul — do. with stand — do, of wood Equilibrium- Figures witli contro of gravity c'liiiHtiiiclcd llicii'ini: crude, triangle, quadiatc, pentagon of brasB, witli capH I'oi placing llinni upon a pointed stand, support included — do. of wood to bo KUKpeudcd at llircailH Mechanism for explaining the stnble equilibrium - Krick, Fig. i;ti . . . Mechanism for explaining Iho indifferent, slablo and vnrinblo equilibrium . — do. witli stand Cone running up-hill Cylinder running up-hill Chinese Stair climber — do. laigi^r 18. W) 10. M (;. k;. W) r>. 00 c. — 2. 25 ;t. 25 •1. - r.. rio :i. 25 i;. 51) 0, Gerhardt, Marqnart's Lager I'bcmischer Uteiisilicii, Buiin. 84. Model of a Cardanlsh Suspension 85. Apparatus for determining tlie stability — Fiick, Fig. 137 86. — do. without adjusting-screws 87. — do. Steinhiiuser's with 3 prisms. — Miillei--Pouillet I. Fig. 66—68 Mi£. Pf. 16. 50 •27. 50 16. 50 20. — 88. — do. Wcinliold, Fig. 69 20. - 89. — do. Kajetan's — Carl's Rep. XIII. pg. 420 . 44. — 90. ObllqueTower for illustrating the principle on which theTowcr of Pisais built 2. 25 91. — do. larger, with plummet 4. 50 92. Model! of a beam of a balance — Woinhold, Fig. 70-73 15. 50 93. — Demonstrating Balance 55. — This apparatus shows all various relations, which may influence upon the sensitiveness and good quality of a balance. C. Gerhardt, Marquart's Lager chemischer Uteusilieu, Bonn. Mk. Pf. Balances or Scales: 94. — Hand-Scale with brass-beam and corn-scales 3 50 to 11. 50 95. — Column-Scales, at prices varying to the sensitiveness . . . 22. — to ItO. — £6. — Chemical Balances, at prices varying according to sensitiveness and capacity of bearing from 21. 50 to 880. — Hydrostatic Scales, see Hydrostatic Weights. 97. — 98. - Weights in sets, the larger of brass, from one gramm to one miliigramm of platine, with tweezers, and centigramm-chrochet in a mahogany-box, from 1 Grain up to __1 2 i 8 16 32 Onnc es M. 22.- 30.60 38.50 55.— 71.50 88.— 1 Set from 1 miliigramm to 1 gramm, of platine, with box .... 19. 50 i:i5 ' r.io No. 96. No. 105 99. — ISet from 1 miliigramm up to Ikilograram, of brass in polished wood-block 22.— 100. — 1 Set from 1 gramm up to 500 gramm, of brass in polished wood-block 16. 50 101. — iSet from Icentigramra up to SOOgramm, of brass in polished wood-block 11. — 102. Model of an Unequal-armed balance. — Frick, Fig. 141 - of wood. . . 9. — 103. — do. iron-made 13. 50 104. — do. brass-made 20. — 105. Model of a welgh-brldge, entirely of metal 33. — 106. — do. simpler, wood made 16. 50 107. Mechanism for demonstrating the elasticity of ivory — Frick, Fig. 143 — 13. 50 108. Glass-Tuft of spun-glass 1. 25 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 109. Bolognian-Flasks 10 pieces 1. 75 110. Glass-Tears 25 pieces 1. 25 111. Joly's Spring-Steelyard. - Miiller-Pouillet I. Fig. 77 27. 50 112. — do. simple 5, 50 113. 'S Gravesande's Apparatus for determining the elasticity of metal-wires. — Miiller-Pouillet 1. Fig. 75 22. — 114. — do. simpler 11. — 115. Dynamometer, simple pattern. — Eisenlohr, Fig. 30 13. 50 116. — do. larger ' 27. 50 117. — do. for traction and pre.ssure 49. 50 118. Coulomb's Turning Balance for Researches about Elasticity by torsion and adhesion 27. 50 119. — do. larger and with adjusting-screws, the scale edged on the glass . 55. — 120. — do. with reading-mirror for exact measurings (Fig. No. 119) .... 82. 50 i:6 1^' No. 117 No. 119. 121. Adhesive Glass- Plates 6. 50 122. — do. of brass 15. 50 123. — Support for these plates - Frick, Fig. 148 10. — 124. Galilei's Falling-Channel to be risen or lowered, with metronome .... 40. — 125. — do. without metronome 26. 50 126. Atwood's Fall Machine, with sheaves, electromagnetic ratch, second's pendulum and electro-magnetic second's stroke 264. — 127. — do. but without sheaves 114. 50 128. — without sheaves, with second's pendulum, perceptible stroke, the ratch is automatically loosened through the pendulum 143. — 129. — quite simple, upon alder-wood stand with pendulum, the ratch is automatically loosened 82. 50 130. — do. like 129, but without pendulum 66. — 10 C. Gerhardt, Marquart's Lager cheroischer Uteusilicu, Bonu. >}. f W • - Bin i ^SiS n © ^1 t= 1112 No. 126. C. Gerhardt, Marquart's Lager cheraischer Utensilieii, Bonu. 11 Mk. Pf. Atwood's Fall Machine 131. - do. Weinhold's, Fig. 58 53. 132. — new construction, with elect romagnetical loosening, with two registering clocli-works and two Leclanche -Elements 330. Immediately after the weight being loosened by the electro- magnet, the clock-works are going on. Each of them bears a second's index. One of these works stops automatically as soon as the aditional weight is lift off from the bridge. The second work stops immediately after the weight has passed through the limited falling-space. Therunning-pulley is made of aluminium- silver and rests upon sheaves. No. 132. 133. MUller's Fall Machine. — Miillor-Pouillet I. Fig. 339 — for the graphic demonstration of the laws of fall 165. — A swinging spring is writing with a lead-pencil upon a freely falling paper. The sledge and the spring ave loosened simul- taneously by electromagnetic force. 134. Apparatus for demonstrating the Fall upon arc and chord — Frick, Fig. 306 — 33. — 135. — do. new construction, with 2 bells indicating the end of the falling times. The chord can be adjusted, both balls are loosened simultaneously 49. 50 136. Apparatus for showing the fall upon various curved lines 27. 50 137. — do. new construction, with 3 bells, the balls are loosened simultaneously 44. — 138. — do., Weinhold's Fig. 64 16. 50 12 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 139. Apparatusfor demonstrating the parabolic fall of Projectiles. —Frick Fig. 277 27. 50 140. — do. larger 44. — 141. — do., Hagenbach's. — Carl's Rep. Ill pg. 441 16. 50 142. Loewy's Apparatus for showing the simultaneous fall of a body thrown in horizontal line and one falling freely — Weinhold, Fig. 60 15. 50 /i r ■:% i;20 1:50 No. 139. No. It]. 143. Centrifugal Machine or Whirling Table entirely of iron, to be used hori- zontally and vertically 49. 50 144. -• do. same as 143, but with a tube for fixing a throttle-valve-model or Watts Steam engine regulator 60. 50 145. — do. same as 144, with a longer axle and with folding-feet. An arrangment is providedin themiddle upon which parts of fixed apparatus maybeplaced 88. — 146. — do. Bertram's, to be used only horizontally 24. 50 147. — do. with arrangment for experimenting with a throttle-valve-model et cet. 27. 50 No. 143. Accessories for the Centrifugal Machine. Some of these apparatus are marked at 2 different prices. The cheaper of them is suitable for the machines 146 — 147, the dearer one for the machines 143—145. 148. — Centrifugal Pendulum 13. 60 149. — do. smaller 5. 50 150. - Watt's Ball Regulator . . . . ■ 16. 50 151. — do. smaller 8. 25 152. — do. with a thrott le-valve-model, but only suitable for the Centrifugal Machine No. 144 a. 145 25. — 153. — do. smaller, suitable only for the Centrifugal Machine No. 147 . . . 14. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 13 Mk. Pf. Accessories for the Centrifugal Machine. 154. — Two brass-balls of different weights, connected together and sliding on a horizontal wire 8. 25. 155. — do. smaller 4. 50. No. 117 u. 153 156. — 157. — 158. — Ball Weighing 100 Grammes, sliding in a horizontal-line with spring- balance for reading directly the centrifugal force 16. 50 do. smaller 8. 25 Centrifugal Balance — Frick, Fig. 287 15. — 1:8 No. 158. 1:e No. 164. No. 154. 159. — do. smaller 160: — Ball weighing 100 Grammes and sliding in horizontal line, different weights can be lifted vertically 161. — do. smaller 9. 50 15. — 5. 50 162. 163. 164. 165. 166. No. 160. No. 16G. Apparatus for showing, that the centrifugal force depends on the velocity of rotation and the size of the radius of gyration — Frick's, Fig. 289 16. 50 do. same smaller 7. 75 August's Spring-Drawer 13. 50 do. smaller 4. 50 Two tubes inclined to another for liquids of different specific gravity 5. 50 14 C. Gerhardt, Mavquart,'s Lager chemischer Utensilieu, Bonn. Mk. Pf. Accessories for the Centrifugal Machine continued. 167. — do., smaller 4. — 168. — Glass-Ballon, to be filled with water and mercury 9. 25 169. - do. smaller 4. — 170. — Glass-Bottle to show the parabolic surface 6. — 171. — do. smaller 2. 75 172. — August's Swinging Siphon 10. — 173. — do. smaller 4. — 174. _ Semicircular Chanel with two freely running balls 8. 25 175. — do. smaller 5. 176. 177. 178. 179. 180. 181. No. 174 No. 176. No. 17S. — August's Ball Beam with several balls of different weight ..... 9. — — do. smaller 4. — — Bertram's Drying Apparatus • . . . . 13. 50 — do. smaller 7. 50 — Bertram's Apparatus for washing minerals 15. — — do. smaller 8. 25 No. 172. No. 180. 182 183 184 185 186 187 188 189 — Angular Weels, to use only with the Centrifugal Machines No 144 & 145, with arrangments for attaching coloured discs 15. 50 — do. smaller, suitable only for the Centrifugal Machine No. 147 ... 10. 50 — Apparatus for demonstrating the difference between the longest and shortest diameter of the earth 14. — — do. smaller 6. 50 — Apparatus for explaining Foucault's essay of pendulum 15. — — do. smaller 5. 50 — Ring, Cylinder and Chain 5. 50 — do. smaller 2. 25 Accessory apparatus to the centrifugal- machine, which belong to other parts of Physics — are marked at the respective chapters. C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 15 Mk. Pf. 190. Schleiermacher's Apparatus for showing, that the centrifugal force is proportionate to the square of the velocity of rotation — Frick, Fig. 286 44. — 191. Centrifugal Railway with ball 16. 50 192. — do. with carriage • 40. — 193. Busolt'b top with swinging-engine 27. 50 194. — do. VVeinhold's, Fig. 56 53. — 195. — do, Schmidt's. Weiohold, Fig. 82 10. — 196. — do. larger • • ■. 16. 50 No. 200. 197. Bohnenberger's Machine 198. — do. larger 199 — improved by Poggendorff, with swinging engine 200. Fessel's Gyroscop 201. — do. larger Eisenlohr, Fig. 91 20, — 33. - 82. 50 16. 50 27. 50 i:i5 1:10 No. 203. No. 207. 202. Magnus's Polylrop 132. — 203. Mach's Apparatus for illustrating the principles, by which the centre of gravity and the surfaces are obtained. — Carl's Rep. IV. pg. 360 . . 22. — 204. Mechanism for Foucault's Pendulum -Essay — Frick, Fig. 302—305 with graduated disc 38. 50 205. — do. Weinhold's, Fig. 89 & 90 110. — 206. — do. Eisenlohr, Fig. 85 44. — .207. Apparatus for explaining the moment of inertia 8. 25 208. Kurz's Apparatus for determining the moment of inertia — Miiller- Pouillet I. Fig. 384 — upon .stand 49. 50 209. — do. other construction, consisting of two balls suspended on threads of different weight with springhammer in the larger ball — upon Stand with sextant 27. 50 16 C. Gerhardt, Marquart's Lager chemischer Uteusilien, Bonn. Mk. Pf. 210. Apparatus for demonstrating the laws of Pendulum, simple making, with three pendula 6. 50 211. — do. new construction, with 6 pendula 16. 50 212. — do. Frick, Fig. 308 40. — 213. Mach's Pendulum Apparatus fitted in such manner, that the plane of the pendulum can be inclined to any wished angle 27. 50 214. Wiedemann's Apparatus for showing, how the resistance of air Influences upon the pendulum, with support. Frick, Fig. 321 — . 6. — 71 i:2U ' """"^ i:?.c No. 210. No. 2U 215. Second's Pendulum upon support 26. 50 216. — do. with audible stroke 40. — 217. — do. with audible stroke and secundum's index . 55. — 218. Convertible Pendulum upon stand, with iron-ball 33. — 219. — do. the ball's of brass and filled with lead 49. 50 1;10 No.209. 220. Grit-Pendulum upon Stand .... 221. — do. swinging seconds 222. Maelzel's Metronome with clock-work 223. — do. with ball I'.IO No. 220. 224. Open Model of a pendulum-clock to explain mechanism et cct. 16. 50 49. 50 13. 50 16. 50 33. - C. Gerhardt, Marquart's Lager chemisuher Utensilieu, Bonn. 17 Open Model of a Pendulum-clock 225. — do. with adjusting screws . . Mk. Pf. 40. 226. — No. 225. do. Tlie index-work can he easily taken away. It is supplied with a contact-mechanism, by means of which it can be connected with an electric dial 55. ^K 5^ ^ "=/"" ' ""-'%.- - .^.Ti^Eir^ -rfS^Z; ^i=^=S&;3e i:io No. 237. 227. Modell of an escapement by anchor, with weight 33. — 228. — do. with spring 40. — 229. Model of a ohronometric escapement with spring 49. 50 18 C. Gerliardt, Murquart's Lager chemischer Utcusilien, Bonn. 230. 231. 232. 233. 234. 235. 236. 237. 238. 239. 240. 241. 242. 243. Mk. Pf. Model of a escapement by cylinders with spring 49. 50 Apparatus of Percussion with 5 box wood 13. 50 — do. with 10 bosen balls 20. — do. with 9 box wood of different weight 33. — do. with 5 ivory balls and 5 lead balls 53. — — do. with 10 ivory-balls of same weight and 3 box wood of different weight, the points of suspension and the sextants are moveable. . . 99. — Apparatus of reflexion — Frick, Fig. 328 '6. 50 — do. Nollet's, the ivory-ball is falling in a vertical line 49. 50 — do. the ivory-ball is thrown horizontally 44. Coulomb's tribometer for sliding friction — Muller-Pouillet I. Fig. 304 . 27. 50 — do. more complete — do. for rolling friction — Muschenbrock's and NoUel's construction - Frick, Fig. 329 4^- ^0 Kommerell's Apparatus for demonstrating the effect of friction upon in- clined planes, - Frick, Fig. 330 5-50 Prony's dynamometrical break 33. — B. Hydrostatics and Hydrodynamics. 244. Tube-level in brass-frames 3. 25 245. — do. with adjusting-screw and scale 10- — 246. — do. Weinhold's, Fig. 92 — special pattern for schools 14. — No 257. 247. Box-level 2. 75 248. — do. larger and finer 5. 50 249. — do. larger still 9- — 250. Apparatus for demonstrating the equal transmitting of pressure in liquids, — Frick, Fig. 149, — serves at the same as model of a Hydraulic Press 82. 50 251. — do. simple — Frick, Fig. 154 6. — 2:)2. — do. Weinhold, Fig. 94 20. — 253. — do. with 3 lateral pistoD.= 33. — C. Gerliardt, Marquiirt's Lager chcmisclier Uteusilien, BoDn. 19 Apparatus for demonstrating the equal transmitting of pressure in liquids 254. — do. with 5 little monomoters 255. Hydraulic Press giving a pressure of 300—500 Kilos, with iron cyliadcr 25S. — do. with brass cylinder Mk. Pf. 20. - 82. 50 110. - 257. 258. 259. No. 265. do. with glass cylinder .' . . . 137. 50 do. with glass-cylinder and with a table 165. — do. with brass-cylinder, may be used also for pressing plants . . . 220. — i:8 !, No. 270. 260. - do. with iron -cylinder, giving a pressure of 500-700 Kilos, — the pressure can be measured by weights 385. — 2(51. — do. with iron- cylinder, giving a pressure of 10,000 to 15,000 Kilos, — 990. — 262. — do. same as proceeding, with safety-valve and manometer 1100. — 263. Mechanism for showing that in fluids pressure is growing with the depth - Weinhold, Fig. 97. - 8. 25 20 C. Gerhardt, Maiqiiart's Lager chemischer Utensilien, Boim. 264. 2GJ. 266. 267. 268. 269. 270. 271. 272. Mk. Pf. Pascal's Apparatus for measuring the pressure of ground, with 4 different tops 27. 50 — do., same, larger 49. 50 — do. Miiller's — Miiller-Pouillet, Fig. 147, with 3 different vessels ■without scale 27. 50 — do. with scale placed on one same board 66. — — Trick's, Fig. 161, with 3 different vessels, without scale 40. — — do. same with scale on one same board 77. — — do. Haldat's — Frick, Fig. 164, with 4 different vessels 49. 50 Model of Real's Press •- 16. 50 — do .larger ■ 33. — 273. 274. 275. 276. 277. 278. 279. 280. 281. 283. 283. 284. 285. 286. l:5 No. 278. Hydrostatic Bellows 16. 50 — do. more simple — Wcinhold's system without stand 5. — Anatomical Siphon 4. Illustration of buoyancy — Frick, Fig. 165 — 2. 75 — do. larger 5. — do. Vogel's 33. — A detailed description will be sent on demand. Apparatus for proving the Archimedic principle, consisting of a glass-vessel with lateral discharge and swimmer — Frick, Fig. 170 — 8. 25 — do. with a graduated glass-vessel 10. — — do. Sire's, with upper-scale balance. — Carl's Rep. X pag. 451 . . 49. 50 — do. consisting of a hollow and a massive cylinder. — Miiller-Pouillet I., Fig. 158 5. 50 — do. larger 8. 25 — do. consisting o fa hollow and a massive cube, each side about I'/e inch 13. 50 — do. each side is 2 inch large 20. — Mechanism for showing, that a solid body can only swim, when it Is pressed from beneath by the fluid. — Wcinhold's Fig. 103 3. — C. Gerliardt, Marquart's Lager cheraischer Utensilien, Bonn. 21 Mk. Pf. 287. Cartesian Swimmer 1. 75 288. do. larger 2. 50 289. Hydrostatical Balance with brass- beams, with two long and one short brass-scale suspended to wires 30. 50 290. — do upon stand 40. — No. 283 291. — do. Mohr's for determining the specific gravity of fluids, complete in a box 49. 50 292. — Westfahl's scale with one branch for determining the specific gravity of scales 49. 50 293. Nicliolson's Weigiit Areometer, made of varnished tin-plate 5. 50 294. — do. brass-made 16. 50 i:2D No 297. 1:10 i.e No. 290. No. 294. 295. — do. of gilt brass with weights and a glass-cylinder in leather-box . . 296. — do. Tralle's of varnished tin-plate with glass and support —Weinhold's, Fig. 104 297. — do. brass-made 298. Graduated Areometers for liquids the specifiic gravity of which is lighter than water 299. — do. with thermometer fused into the glass 300. — do. for liquids, the specific gravity of which is heavier than water . 40. — 19. 50 27. 50 4. — 5. 50 4. — 22 C. Gerhardt, Marquart's Lager cliemisclier Uteusilieu, Bonu. Mk. Pf. Graduated Areometers 301. — do. with thermometer fused into the glass 5. 50 302. — Universal-Areometer for liquids of 0,700 to 2000 specific gravity . . 5. 50 303. — Wittstock's Areometric Case containing two areometers with weights, thermometer and glass-cylinder in a box 49. 50 304. — Trail's Alcoholometer from 0—100" with thermometer fused into the glass Areometers are supplied for any special purposes and with any desired scales. 305. Twenty Glass-Balls of different weight, swimming on the surface or sinking down and thus indicating the specific gravity of liquids . . 306. Cold-Water-Swimmer. A Metal-Ball which swims on cold water and sinks down in warm water 307. — do. larger 308. 309. 310. 311. 312. 313. 314. 315. 316. 317. 318 319. 5. 50 22. 2. 4. 75 50 i:io No. 320. Element -Glass, containing four not mixing liquids of different specific gravity 5. 50 Gramm-Glasses with ground stopper 3. 25 — do. with a thermometer fused into the glass 8. 25 — do. with a hollow glass-stopper 5. — Weinhold's Picnometer, Fig. 51, with tripod -stand and pipette ... 2. 75 Communlcaling Vessels, Frick, Fig. 166 1. 75 — do. one System of three tubes of different width and bent on different manner, upon wood support 2. 25 — do. with 4 tubes 5. _ Channel-Scale — simple pattern for schools 16. 50 — do. larger and upon stand 27. 50 Apparatus for determining the specific gravity of liquids, consisting of a tube bent in the form of an U, with graduated stand — Frick, Fig. 167 11. 50 — do. Babinet's, conisisting of a tube bent in form of two U, with glass- stopcock and graduated support, - Miiller-Pouillet I., Fig. 134. . . 20. — C. Gerhardt, Marquart's Lager cliemisclier Utensilieu, Bonn. 23 Mk. Pf. Apparatus for determining tlie speciflo gravity of liquids 320. — do. Boyle's, consisting of two vertical tubes upoa graduated stand with one common pump 20. — 321. — do. Mohr's, with Rubber-ball instead of the pump 13. 60 322. Oerstedl's Apparatus for demonstrating the compressibility of liquids, with picnometer and air-nianometer — Frick, Fig. 156 — 126. 50 323. — do. Regnault's — MuUer-Pouillet I., Fig. 173 324. — do. Weinhold's, Fig. 112, fitted for the Sciopticou 325. Salleron's Drop-Glasses — Miiller-Pouillet I., Fig. 174 1:15 No. 323. . . 123. 50 44. — . 174 1. 25 326. Wire-Figures for showing Plateau's Equillbricun Figures, one set of 6 pieces 6. — 327. Apparatusforshowing that liquids endeavour to contract -Weinhold, Fig. 115 5. — 328. — do. with three cocks upon a stand 13. 50 329. Plateau's Apparatus showing the rotation of an oil-ball swimming in an alcoholic liquid 27. 50 330. — do. larger 49. 50 24 C. Gerhardt, Marquavt's Lager chemischer Utensilieu, Bonn. 331. 332. 333. 334. Mk. Pf. Plateau's Apparatus showing the rotation of an oil-ball swimming in an alcoholic liquid — do. with clock work 6S. — Four plain plates of glass, wood, copper and brass, each with three threads for suspending at a scale, for measuring the coherence of liquids 4. — Capillary-Tubes, 10 pieces of different width, with graduated stand ... 8. 25 — do. two larger tubes, each of which is connected with three capillary- tubes of different width, for moistening and not moistening liquids, new construction, with graduated stand 11. ^ 1 ;2 i:io No. 337. No. 352. 335. Apparatus for essays about capillarity, consisting of two hinged glass-plates with glass-vessel 13. 50 336. — do. with micrometric-screw 22. — 337. Gay Lussac's Apparatus for measuring capillary attraction. — Miillcr- Pouillet I., Fig. 187 • . . . . 27. 50 338. — do. Pfaundler's. — Miiller-Pouillet I., Fig. 188 33. — 339. Conical Glass-Tube, to show the form of the Meniscus 2. 25 340. — Two-side-tube for same essay 2. — 341. Two Glass-Balls and two wax-balls for the essays about attraction and repulsion produced by capillarity 5. — 342. — 2 plates of thin plate-glass for same essays, suspended on threads 2. 25 343. Dutrochet's Endosmometer. — Muller-Pouillet I., Fig. 212 3. — 344. — do. with graduated rising-tube 4. — 345. — do. with horizontal tube — Weinhold, Fig. 120 — not graduated . . 3. — 346. — do. with graduated scale 5. .50 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 25 347. Apparatus for demonstrating, how evaporation influences upon endosmosis, consisting of two bent tubes. — MuUer-Pouillet I., Fig. 214 n. 215 348. Apparatus for the essays about the velocity of the efflux of fluids, Weisbach'a system, with three discharging -tubes 349. — do. with stuffing-box. — MuUer-Pouillet I., Fig. 412 350. — do. with stuffing-box, fitted for maintaining a constant level . . . 351. — do. complete with different connecting tubes, orifices of discharge of different forms et cet., with arrangement for obtaining a constant level 352. — do. same as 351, but larger, the adjoined tubes are connected with manometers 353. — Mariotte's Vessel for same essays — Miiller-Pouillet I., Fig. 413 . . 354. — do. with different adjoined tubes and orifices of discharge Mk. Pf. 2. 75 20. 49. 50 06. — 165. — 220. - 13. 50 33. - No. 365. No. 360. 355. — discharging Apparatus — Weinhold, Fig. 105 — for same essays. . 16. 50 356. — do. with arrangement for showing how pressure changes, when water is flowing trough long pipes 25. — 357. Apparatus for demonstrating the parabolic fall of fluids . . 55. — 358. — do. with arrangement for maintaining a constant level 66. — 359. Hydraulic Ram. entirely of glass — Weinhold, Fig. Ill B 8. 25 360. — do. of metal and glass — Weinhold, Fig. Ill A 49. 50 361. Poisseuille's Apparatus for examining the efflux of fluids through capillary tubes. — Miilier-Pouillet I., Fig. 432 5. 50 362. Segner's Water-Wheel, simple, — Frick, Fig. 338 6. 50 363. — do. of varnished tin-plate 11. — 364. — do. of glass, with brass-furniture 22. — 365. — do. Carl's, serving at same time as a reaction-wheel for gases. — Carl's Rep. IV. pag. 118 44. — 366. Woltmann's Hydrodynamic Wing, for measuring the rapidity of currents . 49. 50 367. — do. Baumgarten's with wings similar to water-screws 55. — 368. — Hydrometric Pendulum 20. — 26 C. Gerhardt, Marquart's Lager ehemisolier Uteiisiliea, Bonn. Mk. Pf. C. Aerostatics and Aerodynamics. 369. Apparatus for illustrating Mariotte's Principle — Frick, Fig. 202 — con- sisting of a two-sides-glass-tube upon a graduated board 10. — 370. — do. with a steel-stop-cock 16. 50 371. — do. with two steel-stop-cocks - 27. 50 372. — Weinhold's, Fig. 123 53. — 378. — for proving Mariotte's Principle, when the atmospheric pressure is less than one atmosphere — Miiller-Pouillet I., Fig. 258 20. — 374. — do. with graduated glass-tube and stop-cock 27. 50 375. — do. Pouillet's for different gases. — Miiller-Pouillet I., Fig. 266 . . 99. — 376. Schulze-Straussberg's Apparatus for illustrating the Barometer 49. 50 Serves also for explaining Mariotte's Principle; 5 feet long. 377. — do. same as 576, long only 4 feet 38. 50 378. — Schulze-Straussberg's Apparatus for illustrating the Barometer, cannot be used for explaining Mariotte's Principle, long only 3 feet .... 27. 50 379. — do. same as 376, may also be used for explaining the siphon ... 58. — 380. — do. same as 377, serves also for explaining the siphon 44. — 381. — do. same as 378, serves also for explaining the siphon. 33. — The apparatus 378 and 381 may also serve for showing, how the tension of gases diminishe, when their volume grows larger. — The construction of the apparatus 379 and 380 may be perceived from figure 379, in which the length of the apparatus and the place of the stop-cock is not shown correct, 382. Mercury-Barometer, simple pattern of a siphon-barometer 20. — 383. — do. with index 33 _, 384. — simple vessel-barometer 11. 385. — do. Bertram's, iron-made 18. More particulars about Mercury -Barometers are found at Chapter "Meterology". 386. Anero'id-Barometer, Bourdon's system, with open work 33. — 387. — do. Vidi's with open work 11. — 388. August's Nivelling-Barometer 44. — A full description of this instrument will be sent on demand. 389. Huyghen's Variating-Barometer. - Miiller-Pouillet I. Fig. 250 20. — 390. Say's Slereometer. — Miiller-Pouillet I. Fig. 259 5. _ 391. Kopp's Volumenometer. — Miiller-Pouillet I. Fig. 160 49. 50 392. — do. Regnault's. — Miiller Pouillet I. Fig. 261 53. — 393. Siphon-Barometer upon varnished board-not filled 2 75 394. - do. filled ' .' 3" 35 395. — do. -with silvered metal-scale, not filled ^ . 3. 25 396. — do. filled . . . . 4. _ 397. Closed Mercury-Manometer — Frick, Fig. 265 16. 60 398. Apparatus bor showing, that pressure is uniformly transmitted in gases, glass-made, with 5 small manometers 5. 50 399. — do. brass-made 33. — G. Gerhavdt, Marquart's Lager cliemischer Utensilien, Bonn. 27 400. Glass-Siphon 40J. — with handle 402. — with handle and ground glass-stoppei' Mk. Pf. 1. 25 1. 75 2. 75 403. Suction-pipe, glass-made 404. — do. larger 405. — do. with lateral sucking tube 406. — do. with lateral sucking tube and stop-cock 407. — Equicrural Siphon with sucking tube — Weinhold, Fig. 134 .. . 408. — Turning Siphon of glass with glass-cylinder. • 409. — Three-sides-Siphon -. 90 1. 50 2. 75 4. — 4. — 3. 25 2. 25 28 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Suclion-pipe 410. — do. with sucking-tube and stop-cock . . . 411. — do. with sucking-tcibe and valve 412. Tantalus-Cup, glass-made 413. — do. of varnished plate — Frick, Fig. 241. 414. — do. brass-made No. 430. 415. Magic Funnel glass-made 416. — do. of varnished plate. — Frick, Fig. 250 417. — do. brass-made 418. 419. 420. 421. 422. 423. 424. 425. The Widow's Oil-Cruet, of varnished plate. — Frick, Fig. 251 — do. brass-made Magic Can, glass-made — do. with handle — do. of varnished plate. — Frick, Fig. 252 — do. brass-made Sieve of the Vestal, of varnished plate. — Frick, Fig. 251 . — do. brass-made Mk. Pf. 4. — 3. 25 3. 25 3. 25 6. 50 3. 25 3. 25 G. 50 5. — 9. — 3. 25 5. — 5. — 9. — 3. 25 G. 50 C. Gerhurdt, Marquarfs Lager chemischer Utensilien, Bonn. 29 426. Magic Barrel, glass-made, for explaining the principle. 427. — do. of varnished plate. — Frick, Fig. 257 . . . . No. 446. 428. — do. brass-made 429. Heron's ball, simple, glass-made. 430. 431. 432. Mk. Pf. 3. 25 5. — 9. — 1. 75 No. 4.17. — do. with brass-stop-cock 3. 25 — do. larger 5. 50 — do. with valve and stop-cock. — Frick, Fig. 260 11. 50 30 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 433. Herons Fountain, glass made 3. 25 434. — do. upon wood-stand 5. 50 435. — do. larger, of varnished plate with brass-stop-cock — Frick, Fig. 256 '22. — 436. — both vessels glass-made with brass-fittings upon tripod-stand .... 49. 50 437. Intermittent Fountain — glass-made — Weinhold, Fig. 138 3. 25 438. — do. upon stand 6. 50 438a. Interrupted Fountain, of glass and brass, with receiver and dish of varnished zinc. On metal-stand 27. 50 or 40. — 439. Interrupted Siphon, glass-made — Weinhold, Fig. 138 1. 75 440. — do. with brass-trimmings 5. — 441. Model of a Sucking-Pump, entirely of glass 2. 50 442. — do. with brass-trimmings, upon stand and with water-tank 13. 50 443. — do. with brass-trimmings upon high stand and with water-tank ... 27. 50 1:10 No. -151. 444. Model of a forcing-pump, glass-made 3. 25 445. — do. with brass-trimmings upon stand with air-vessel and water-tank 22. — 446. — do. larger 33. — 447. Model of a sucking- and forcing-pump, upon mahagony-stand may be brought in activity by the same lever, with air-vessel and water-taok ... 44. — 448. Model of a fire-engine, entirely of glass 4. 50 449. — do. with brass-trimmings upon stand with water tank 25. — 450. — do. larger 40, — 451. — do. made exactly as a large fire-engine, with wheels and with water-tank 82. 50 452. Model of a deep-measurer — Weinhold, Fig. 140 5. — 453. Model of a diving-bell 16. 50 454. — do. with light-holder and India-Rubbcr-blower 33. — 455 Doebereiner's Biower. — Frick, Fig. 266 6. 50 456. Water-Jet-Blower — Weinhold, Fig. 23 28. 50 457. Bunsen's Water-air-pump 19. 50 458. — do. with barometer and regulating stop-cock 25. — 459. — do. Arzberger & Zulkowski's — Weinhold, Fig. 163 44. — 460. — do. entirely of glass — Weinhold, Fig. 164 11. — C. Gerbardt, Marquart's Lager cbemischer Utensilien, Bonn. 461. 462. 463. 464. 465, 466. Mk. Pf. Geissler's Mercury-Air-Pump. — MuUer-Pouillet I. Fig. 291 220. — — do. modified construction — Weinhold, Fig. 157 — for 2 pints mercury 192. 50 — do. for 1 pint mercury 165- ~ — do. Sprengel's — Weinhold, Fig. 156 66. — — do. Topler's, modified by Bessel-Hagen — Annalen der Pliysik und Ciiemie XII 3 Piston-Air-Pumps. 1. Stop-Cock-Air-Pumps with one chamber. — Liebig's Hand-Air- Pump with two locking-stop-cocks and one changing- cock, with tree-screw 220. 33. - 467. — do. with vertical chamber and changing cock fixed on a wood-board. Length of the chamber 9 Inch, diameter I'/s Inch, diameter of the plate 5 Inch 40. No. 471). 468. — do. with slope chamber changing cock and cramp for screwiog at a table. Length of the chamber 10 Inch, diameter I'/j Inch, diameter of the glass-plate 7Vj Inch. The changing-cock is fitted with a hermetic brass-cone by which the air enters 55. — 469. do. with slope chamber and changing-cock, fixed on a polished wood- board with cramp for screwing. Length of the chamber 10 Inches, diameter I'/s Inch, diameter of the plate S'/j Inches, also fitted with a hermetically ground brass-cone by which the air enters 55. — 470. — do. same as 469, but with Iron-Support 64. — 471. — do. same as 470, with a manometer placed on the side 83. 50 472. — do- with a horizontal chamber, with rack and pinion — Weinhold Fig. 148 137.50 32 C. Gerhardt, Marquart's Lager cliemischer Uteusilien, Bonn. 473. 474. Mk. Pf. 2 Valve- Air-Pump with one chamber. Mitscherlich's Hand-Air-Pump with two locking-cocks and valves . . 22. — Small Valve-Air-Pump with slope champer, without locking-cock upon iron-stand. Length of the chamber 7 Inch, diameter 1 Inch, diameter of the plate 6 Inch 22. — No. 474. 475. — do. exactly as 467, but fitted with valves and locking-cock 476. — do. exactly as 468, but fitted with valves and locking-cock 477. — do exactly as 469, but fitted with valves and locking-cock 30. 55. 55. 1:20 No. 480. 478. — exactly as 470, but fitted with valves and locking-cock 64. — 479. — exactly as 471, but fitted with valves and locking-cock S3. 50 480. — do. Bianchi's, with double-acting oscillating metal chamber, swinging- wheel, glass-plate upon iron-stand with ludia-rubber-tube. Length of the chamber lllnch,, diameter 3'/a Inch., diameter of the glass plate 9'/j Inch., diameter of the fly-wheel S'/, feet 573. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 33 Mk. Pf. Piston -Air -Pump. 481. — do. same as 480, bat smaller. Length of the chamber S'/s Inch., diameter 2'/2 Inch 418. — 482. — do. Dcleuil's, with free piston and Babinet's cock, with automatical regulator and large fly-wheel 715. — 3. Cock-Air-Pumps with two chambers. 483. — new construction, with oscillating metal-chambers, automatical regulator and fly wheel 330. — This pump is evacuated by turning the fly-wheel continually in one and the same direction. The cocks are bored in a peculiar manner. Steering is done by the oscillating suckers. - ^t'M'HyitiiijimiJMfi MMirmimiTiMm^ No. 483. 484. — Air-Pump with Grassmann's Stop-Cock, metal-chambers and manometer fixed on a mahogany board with iron-cramp for screwing it on a table. Length of the chambers 8 Inch., diameter 2 Inch., diameter of the plate 8'/j Inch 253. — 485. — do. same, but with glass-suckers and larger. Length of the chambers 8'/j Inch., diameter 2 Inches 302. 50 4. Valve- Air-Pumps with two Chambers. 486. — Air-Pump with Babinet's Stop-cock and glass-chambers, manometer fixed on a mahogany board, with iron cramp to screw it on a table. Length of the chambers 8 Inch., diameter 2 Inch., diameter of the plate 8Vj Inch 247. 50 487. — do. same as 486, but larger. Length of the chambers 8'/2 Inch., dia- meter 2 Inches 302. 50 3 34 C. Gerhardt, Marquart's Lager chemischer UteusilieD, Bonn. Mk. Pf. Valve-Air-Pump with two Chambers. 488. — do. extra large and screwed on a peculiar table. Length of the chambers 10 Inch., diameter 2'!^ Inch., diameter of the plate 10 Inch. 412. 50 Supplementary Parts for Air-Pumps. 489. — Plate fixed on a iron tripod-stand with locking-cock, diameter 6 Inch. 22. — 490. — do. diameter 8 Inch 29. 70 491. — do. diameter 10 Inch 39. 50 492. — Tube with screw for connecting the plates of the air-pumps with pe- special plates or other apparatus 6. 60 493. — do. with stop-cock 10. — 494. — Connecting Tube with wire-spiral, one yard 4. 50 (N. B. 90 Centimeter = 1 yard.) 495. — Receiving Vessels of strong, white glass with button and large plain- ground border. Approximative Height 3 4 6 4 6 8 Inches ~„ Diameter ¥f^ 27^ ¥U 4 4 4" „ Price 1.20 1.50 2.— 1.75 2.25 2. 75 Mk. Approximative Height 4 6 8 10 ll'/j 6 Inches ~„ Diameter 6 6 6 6 (5 8~ „ Price 2.25 2.75 3.50 3.75 4.50 4.— Mk. Approximative Height 8 10 12 IS'/s 16 Inches „ Diamete^r 8 8 8 8 8 I Price 5.— 5.60 6.50 8.25 U. — Mk. Receiving Vessels can be supplied also in any other sizes and will be charged moderately. 496. — Receiving Vessels with stuffing-box: Approximative Height 6 9 11'/ , Inches „ Diameter 6 7 8 „ Price 11. - 16.50 25.— Mk. C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 35 Mk. Pf. Supplementary Parts for Air-Pumps. 497. — Barometer -with higli Receiving Vessel. Miiller-Pouillet I. Fig. 286 . 27. 50 498. — do. with scale 33. — 499. - do. Frick, Fig. 216 29. 75 500. — do. with scale 39. 50 501. — shortened Barometer, testing barometer with scale 3. 30 502. — do. larger 5. — 503. — do. larger still and with receiving vessel to screw on 11. 50 504. — Bourdon's Ring tor screwing on the air- pump -plate, serves for ex- plaining the metal-barometer and the metal-manometer 20. — 505. — do. with plain ground stand for placing on the air-pump-plate ... 24. 75 No. 503. 506. — Apparatus for determining the gravity of the air, consisting of a glass- ball with stop-cock, fitted to be screwed on the plate 8. 25 do. larger 13. 25 do. same as 506, with hermetically closing stand for placing on the plate 11. — 509. — do. same as 507, with hermetically closing stand for placing on the plate 16. 50 do. — Weinhold, Fig. 150, entirely of glass with two locking stop-cocks 13. 75 Dasymeter 10. — do. larger 24. 75 Ring for causing bladders to burst, glass-made 1. 75 do. made of metal 6. 60 Apparatus for showing that air presses equally to all directions, with hermetically closing standmade of iron 16. 50 do. made of brass 29. 75 Magdeburg brass-hemispheres with strong and easy handles Diameter 3 3V^ 4 5 Inche s for screwing 12.50 20.- 24.75 29.75 Mk . with hermetical stand 15. 50 23. 75 27. 50 33. — Mk. 3* 507, 508, 510, 511. 512, 613, 514, 515, 516, 517, 36 C. Gerhardt, Marquart's Lager chemischer Utensilieu, Bonu. Mk, Pf. Supplementary Parts for Air- Pumps. 518. — Mercury Rain, simple 519. — do. larger 520. — do. double. The vessels are fitted in such manner, that mercury must remain therein, and can never be poured out 521. — do. same as 520, but larger 522. — Mechanism, for showing that air extends, when pressure is lessened, consisting of an animals bladder, weights and ball 523. — do. for same essay, consisting of an Tndia-Rubber-ball with cock . . 524. — Mechanism for causing, that a hen's egg perforated at the pointed edge empties into the receiving vessel 525. — Mechanism for showing, that a siphon ceases to flow as soon as the ordinairy pressure of the air in lessened — Frick, Fig. 221 ... . 2. 75 6. 60 13. 25 16. 50 8. 25 2. 75 5. 50 2. 75 526. - 527. — 52S. - 529. — 530. — 531. — 532. — 533. - 534. — 535. - 536. - 537. — 539. Mechanism for showing, that the Ueron's Ball begins to flow as soon as the pressure of the air in lessened — Frick, Fig. 221 1. 75 Lever-Fountain, for screwing on the air-pump-plate 8. 25 do. with a hermetically closing brass-stand 1 1. 50 do. same, larger, with convex glass-tube and hermetically ground brass-stand 16 50 Wheel reacting against air, made entirely of glass, — this wheel turns under the receiving vessel when air is being evacuated 6. — Gun-Lock, to be loosened by the stuffiog-box — Frick, Fig. 219 . . 27. 50 Freezing -Apparatus, consisting of glass-cup, clock-glass, tripod-stand and small receiving- vessel 9 75 do. larger ^ ^q Falling-Tube, long l'/^ yard, for screwing on to the air-pump-plate . 13. 25 do. with hermetically ground brass-stand 18. 25 do., 4 Inches long, with stuffing-box and 4 clack-valves 53. — Winged Wheel, to show the resistance of air — Weinhold, Fig. 155 16. 50 Double mill for same essay, consisting of two little wind-wheels with horizontal or vertical wings with rack and weight 27. 50 do. with spring 22 G. Gerliardt, Marquart's Lagev chemischer Utensilien, Boun. 37 Mk. Pf. Supplementary Parts for Air-Pumps. 540. — Sound-Apparatus -n-ith clock-work 20. — 541. — do. with electro-magnetic bell, the receiving vessel fitted with pole-screws 28, 60 542. — do. simple, consisting of a glass-ball with metall- clock therein which may be screwed to the plate 11. — 543. — do. same as 542, with a hermetic brass-stand 16. 50 No. 519 u. 521. No. 523 n. .120. Wooden Models of Air-Pump — Stop- Cocks, made in profile for showing the inner arrangement: 544. — Three-Way-Stop-Cock 13. 25 545. — Grassmann's Stop-Cock 20. — 546. — Babinet's Stop-Cock 22. — 547. — Stop-Cock for a two-chamber-air pump — new construction .... 22. — 548. Gay-Lussac's Force-Pump with two lateral stop-cocks 55. — 549. — do. with receiving vessel 99. — 550. — do. Silbermann's with two foot-valves and two locking stop-cocks mounted on iron-stand — Miilier-Pouillet I., Fig. 299 66. — 551. — do. with receiving vessel HO. — 552. — Hand-Force-Pump with simple foot-valve 33. — 553. Heron's Ball, copper-made, for screwing on to 552 22. — 38 G. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 554. Mechanism for cracking bladders, to be screwed on to 552 11. 50 555. Compression-Fountain, made of glass and metal, for screwing on to 552. 16. 50 556. Heron's Ball with Force-Pump, upon stand 39. 50 557. Air-Gun with Force-Pump 99. — 558. Jndia-Rubber-Balloon, to be filled with hydrogen or coal-gas 2. 75 559. — do. made of collodion 1. 75 560. Silver-plated copper-plate for producing Moser's breathed pictures. ... 3. 25 561. Mechanism for proving, that heat is produced, when gases are absorbed — with thermometer — Frick, Fig. 271 5. — 562. Mechanism for showing, that gases are absorbed by solid bodies and fluids, consisting of a glass-vessel and one glass-tube closed at one end. — Miiller-Pouillet I. Fig. 320 1. 75 563. Bunsen's Absorbtiometer ~ Miiller-Pouillet I. Fig. 324 154. _ 564. Apparatus for Berthollet's Experiments for showing that gases are mixing In equal volumes — MuUer-Pouillet I. Fig. 326 22. — 565. — do. simple, consisting of two glass -cylinders of equal size, one her- metically ground upon the other 4. _ 566. Apparatus for proving by experiment, the diffusion of gases when passing through porous partition-walls 3. 25 567. — - do., new coustructioa with 2 manometers, upon a stand 33. — 568. — do. Ansell's system, so called Gas-Indicator, with electrical contact . 16. 50 569. — do. Weinhold's. Fig. 170 4. 50 570. Bellows with glass-sides, for showing its principle 13. 25 571. Model of a Cylindrlc Blower, glass-made with brass-trimming. — Miiller- Pouillet I. Fig. 440 39. 50 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bona. 39 Mk. Pf. 572. Bunsen's Apparatus for determining the specific gravity of gases by means of tlieir velocity of escaping. — Miiller-Pouillet I. Fig. 442 53. — 573. Hacliet's Meclianism for malting Clement's and Desormes's essay. — Miiller- Pouillet I. Fig. 455 8. 25 574. — do. simpler 2. 75 575. Mechanism for proving that air Is evacuated In the essay of Clement and Desormes — Miiller-Pouillet I. Fig. 447 10. — 576. Model of Reichert's Injector. — Miiner-Pouillet I. Fig. 448 2. 75 577. Dispersing-Apparatus. — Miiller-Pouillet I. Fig, 449 1. 75 578. Air-Reaction-Wheel — Weinhold, Fig. 159. — It may also be connected with the gas -pipe and the gas lighted at the opening 5. 50 579. Model of a Parachute. — MuUer-Pouillet I. Fig. 452 5. 50 580. Screw-Flyer, serves for explaining the action of the ship-screw. — Miiller- Pouillet I. Fig. 455 & 556 1. 50 581. — do. larger 3. 25 582. Apparatus for explaining the deviation of projectiles, Ptaundler's system. Miiller-Pouillet I. Fig. 644—646 a a 33. — 583. — do. Beetz's System. — Carl's Rep. IV, pag. 183 24. 75 584. Apparatus for examining the motions which take place, when gases enter In a space already filled with other gases — Reusch's system. ... 8. 25 585. — do. simpler — Frick, Fig. 357 — with handle 4. 50 586. — do. Weinhold's system, Fig. 181 13. 25 D. Models of Machines and Parts of Machines. Working Models of Steam-Engines, may be put into action by alcohol- or gas-heating and by compressed air. 587. — High-Pressure-Steam-Engine with oscillating cylinder 20. — 588. — High-Pressure -Steam-Engine with upright cylinder and slide-steering 132. ~ 589. — do. same as precedent, but larger, with gauge-cock, regulator, spring- manometer and copper-boiler 275. — 590. — do. same as 589, with a profile-model moved from the tty-wheel-journal 324. 50 691. — do. same as 589, with sucking- and force-pump and with spring- fountain 352. — 592. — Lying High -Pressure -Steam -Engine with expansion-steering, copper- boiler with all fittings 385. — 593. — do. same as precedent, but larger 550. — 40 C. Gerhardt, Marqaart's Lager chemischer Ulensilien, Bonn. Working Models of Steam-Engines, may be put into action by alcohol-or gas-heating and by compressed air. 594, _ Watt's Atmospheric Steam-Engine 595 - Watt's Double- Acting Steam-Engine with condensator, double parallelo- gram, air- and feed-pump, spring-manometer, regulator, copper-boiler and complete fittings Mk. Pf. 165. — 528. No. 590. 596. — Locomotive, constructed exactly as a large one, with simple steering, only with progressive motion ^^''- 597. — do. larger, with double-steering for progressive and backward motion, upon 6 wheels, with all fittings for the boiler 341. — £98. — Bails for the above locomotive-models, one yard 10. — 599. — Model of a Wheel-or Screw-Steamer with 2 steam-cylinders .... 165. — 600. — do. larger with all fittings for the boiler 550. — 601. Model of Lehmann's Hot-AIr Machine 8-2. 50 602. — do. with regulator and water-cooling-pump 132. — 603. Model of a Gas-Motor 82. 50 604. — do. larger '^^- ~ 605. - do. System Otto Langeu ^•'"- C. Gerhardt, Marquart's Lager chemischer Utensilien, Bouu. 41 Mk. Pf. 606. Model of Schmidt's Water-Motor 82. 50 Vertical Water-Wheels and Turbines 607. — Overshot-Watcr-Wheel with sluice and Water-course 27. 50 608. — do. quite simple 10, — 609. — breast-wheel with sluice and water-course . 610. — do. quite simple 611. — Poncelet's Water- Wheel, with water-course 27. 50 10. — 39. 50 612. — Model of a Turbine, brass-made with glass-wall 132. — 613. — Model of a Screw-Turbiue 16. 50 Profile Models of Steam-Engines. 614. — Profile Model of a Iligh-Pressure-Engine with oscillating cylinder, of metal and wood, with turning-crank 55. — 615. — Profile Model of a High-Prcssure-Eugine with upright cylinder, of metal and wood, with turning-crank 88. — 42 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Profile Models of Steam-Engines. 616. — Profile Model of Watts Low-Pressure-Enginc, of metal and wood, with turning-crank 324 50 617. — Profile Model of a Locomotive for progressive and backward motion, of metal and of wood, with tiiruing-crank 324. 50 C18. — Profile Model of a Steam -Cylinder with slide-steering of metal, with tarning crank 29. 75 No. CIS. 619. — do. of wood 20 620. — do. of metal with regulator and throttle valve 49. 50 621. — Profile Model of a Screw -Steamer, made of metal and wood, with turning-crank 335. _ 622. — Profile Model of Watt's Low-Pressure-Engine, made of wood, may be moved by a crank 33. C. Gerhardt, Marquart's Lager chcmischer Utcnsilien, Bona. 43 Mk. Pf. Profile Models of Steam-Engines 623 i — Profile Model of a Locomotive, of wood, with turning-crank .... 33. — 624. — Profile Model of the Machine of a Wheel -Steamer, of wood, with tarning-crank 49. 50 625. — Profile Model of the Machine of a Screw- Steamer, made of board, with tarning-crank 71. 50 626. — do. with 4 coupled cylinders 132. — 627. — Glass-Frame for the models 622-626, each 13. 25 Agricultural Machines 628. — single-share-swinging-plough 55. 629. — single-share-plough with cart 110. 630. — single-share-eariQg-plough with cart 110. 631. 632. 633. 634. 635. 636. 637. 638. 639. 640. 641. deep-earing-plough with cart 132. — Miner or subsoil-plough 55. — Heaping plough 55. — Two-Shares-plough 93. 50 Three-Shares-pIough - 110. — Paring and drill-plough 110. — Two -fields-harrow 49. 50 Universal-Sowing-Machine 165. — Horse-Rake HO. — Threshing-Machine with straw-yielder aud horse-work 660. — Corn-Squashing-Machine 132. — 44 C. Gerhardt, Marquart's Lager chemischer Utensilieu, Bonn. Mk. Pf. Agricultural-Machines 642. — KibbliDg-Mill 165. — All these Models of Agricultural- Machiuess are made exactly as the original Machines and of the same material. Simple Machines 643. - Model of a Reel, of wood 2. 75 644. — do. of metal 11. 50 645. — Model of a Differential- Reel, of wood 11. — 646. — do. of metal 22. — 647. — Model of a Ship-Pulley, of wood 2. 75 648. — do. of metal 11. 50 649. — Model of a Pulley with dented wheel and mover — Miiller-Pouillet I. Fig. 38 — of metal 33. — 650. — Model of a crane, of metal 82. 50 651. — Model of a Screw-Jack. — Miiller-Pouillet I. Fig. 44 — of mttal . 27. 50 652. — Model of a Draw-Beam, of wood H- — 653. - do. of metal 27. 50 654. — - Model of a ram 10- — G. Gerhardt, Marquart's Lager chemischer Uteusilien, Bonn. 45 Mk. Pf. Simple Machines — Model of a steara-iam 66. — — Model of a chain-pump 82. 50 Models of Valves. — Model of a clack-valve, of metal — do. same of glass and metal — Model of a ball-valve, of metal — do. of glass and metal . . . . _ — Model of a conic- valve, of metal — do. of glass and metal — Model of a plate-valve, of metal — do. of glass and metal 1 655. 656. 657. 658. 659. 660. 661. 662. 663. 664. 5. 50 8. 75 5. 50 8. 75 5. 50 8. 75 5. 50 8, 75 1:10 No. 635. 665. — Model of a bladder- valve, of metal 5. 50 666. — do. of glass and metal 8. 75 667. — Model of a safety-valve 5. 50 668. — all the above valves upon same board to gether made, of metal . . 2G. 50 669. — do. same of glass and metal 44. — Transmission of a rotatary motion from one axis of rotation to another. 670. — Running Strap, with wooden-pulleys 10. — 671. — do. same, entirely of metal 16. 50 672. — do. for crossed straps, with wooden-pulleys 10. -— g73_ _ do. as 672, but entirely of metal 16. 50 g74. — do. with right-angle-axles, the pulleys of wood 10. — 675. — do. same as 674, but entirely of metal 16 50 676. — Wheel and Pinion, of wood 6. — 677. — do. of metal 16. 50 678. — Endless Screw with usual dented wheel 8. 25 679. — do. same of metal 20. — 680. — do. with wheel dented in shape of screws, of metal 22. — 681. — Two Angle-Wheels, of metal 20 — 682. — Cog-Wheel with lantern, of metal 22. — 46 C. Gerhardt, Marquart's Lager chemisuher Utensilien, Bonn. Transmissions of a rotatory motion from one axis of rotation to another. 683. — Hooks Key, of wood 684. — do. same of metal Mk. Pf. 24. 75 39. 50 No. 670. A rotary motion is changed into one going to and fro in upright direction. 685. — Crank 39. 50 686. — Bow- Triangle 44. — 687. 688. 689. 690. 691. 692. I 6 No. (;87. No. *:9o. Heart Motion 44 Watt's Parallelogram 27. 50 Simple Eccentric Catch, variable 39. 60 ■ Double Eccentric Catch with twofold steering for moving locomotives forward and backward 82. 50 To- and fro-Motiou by means of 3 half-dented wheels 44. — Planetary Wheel for upright motion 66. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 47 Mk. Pf. II. Theory of Uudiilation. 693. Mechanism for producing transversal waves, consisting of a brass-spiral, of S'/i yards length and fitted with rings on both sides 16. 50 694. — do. consisting of cord with balls sliding on it 8. 25 695. — do. consisting of an India-rubber-strap with sliding balls, Weinhold's system 16. 50 696. Apparatus for explaining tlie undulation of liquids — Eisenlohr, Fig. 214— 21G 44. — 697. Wiedemann's Apparatus for representing the progression and repulsion of waves produced by liquids. — Frick, Fig. 362 39. 50 698 Apparatus for explaining the repulsion and interference of waves, consisting of 3 different mercury-vessels and 2 pipettes 26. 50 699. Miiller's Stroboscopic wave-disl, 20. — or 26. 50 1136. — do. fitted for drawing, with a leus fitted with rack and piniou and a mirror. - MiillerPouiUet II. 1. Fig. 283 82. 50 1137. - do. as 1136, with a Chevallier's prism with convex polished surfaces in place of the lens and mirrors 99. - 1138. Photographic Apparatus, for scientific and technical purposes suitable for all Climates Size of plates : 3 X 4 Inch '7X9 Inch 18 X 10 Inch Mk. Pf. I Mk. Pf. ! Mk. Pf. Else - Wood - Camera with j ! dark-slide for 1 plate . ; 33. - I 105. 50 | 119. — Aplanatical Lens with 5 diaphragms 62. 75 , 154. — | 154. — Printing-frame for paper- j 1 pictures 2. - ! 10. - | 11. 50 3 Papier-Mache-Plates . . ; 8. 25 j 23. - : 31. 50 Dark-room Lantern . . . i 16. 50 | 20. - j 20. - complete Mk. j 122. 50 j 312. 50 ] 335. 50. 76 C. Gerhardt, Marquart's Lager chemischer DtensilieD, Bonn. 1139. Mk. Pf. Photographic Apparatus. — the same, easey portable and specially arranged for travellers et cet. Size of plates Mahogany-Camera with one double-dark- slide for 2 plates 77. — 143. — Folding stand, with bag 29. 75 33. — Aplanatical Lens with •'> diaphragms. . 62. 75 154. — Printing-Frame for paper-pictures ... 2. — 10. — 3 papier-mache-Plates 8. 25 23. — Dark-room-Lantern 16. 50 20. — complete Mk. 196. 25 1 383. — Fnll instruction for making negetives and printing copies will be furnished with each apparatus. — They are iitted to use with dry-plates. Accessories for the above mentioned apparatus: 3X4 Inch Mk. Pf. 7X9 Inch Mk. Pf. 8 X 10 Inch Mk. Pf. 165. — 36. 25 154. — U. 50 31. 50 20. — Size of plates 1140. 1141. — 3X4 Inch Mk. Pf. Bromide of silver - Gelatine - Dryplates 10 in packet Permanent sensitized Albumine -Paper 24 sheets All other Photographic Apparatus, Accessories, furnished at moderate prices to order. 4. — 1. 50 7X9 Inch ] Mk Pf. 13. 25 7. 75 418. — 8 X 10 Inch Mk. Pf. 19. 25 8. 25 Chemicals etc. 1:8 nr — No. 1153. No. 1155. 1142. — Neutral oxalate of potash per pound 3. 25 1143. — Sulphate of Iron „ —.60 1144. — Hyposulfite of Potash . . . . : „ —.60 1145. — Fixing-salt for paper-prints „ — .90 1146. Wollaston's Camera luclda with stand 29. 75 1147. — do. with coloured glasses and two lenses 40. — 1148. — do. Amici's with one prism and a plain parallel-mirror 40. — 1149. — do. Sbmmering's for placing on a microscope. — Miiller-Pouillet II. 1. Fig. 286 16. 50 1150. — do. Nobert's, for placing on a microscope. — Miiller-Pouillet II. 1. Fig. 287 20. - 1151. — do. Nachet's, for same purpose. - MuUer-Pouillet 11. 1. Fig. 288 . 27. 50 1152. Lamp for Magnesium-Light with clock-work and concave mirror .... 49. 50 1153. — do. with arrangement to unwind the magnesium-wire equally. ... 66. — 1154. — do. larger with 2 magnesium-wires 77. — 1155. — do. with arrangement to unwind the magnesium-wire equally. ... 93. 50 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 77 Mk. Pf. Magnifying Glasses 1156. — in horn- cell 1. 2. 25 \\m. — do. „ with two plain-convexe — for botanists, in horn-cell with disl 27 1158. les fitted with 1 2 3 lenses diameter of the lens about '/j Inch 1. 50 2. 60 3. 25 " U 7» V 1. 75 2. 75 4. 25 " 5> 1 » 2. 25 3. 50 4. 75 " " 1 M )! 2. 50 4. 25 5. 75 5> >i 1 /j n 2. 75 5. - 7. 25 »» 1) 1 la n 4. - 5. 75 8. - 1159. convex lenses of about l'/^ Inch d — Cylindric Magnifying Glass, withou ameter 2. 2. 25 1160. t cell . . . 1161. — do. without cell 2. 3. 50 1162. — Coddington's Magnifying-Glass with ground diaphragm 25 1163. — do. achromatic, in brass-cell, with one lens. . 4. 25 1164. — do. „ „ with two lenses and a handle .... 6. 50 1165. — do. with two lenses and ball-hinge-stand, prices varying according to size frnm 16. 50 to )CUS . . . 27. 33. 50 1166. — do, Brucke's System, achromatic, with large distance of f( 1167. — do. same with stand 44 1168. 1169. 1170. 1171. 1172. 1173. 1174. 1175. 1176. Simple microscope. — Microscope for preparations, achromatic with 3 objectives of 15, 25 and 40 fold magnifying power Compound Microscope. — Cylindrical- Stand with sliding tube. With 1 pincette, 1 testing -pre- paration, and 2 object-holders in a box. 1 objective- lens, 1 ocular, not achromatic. Linear-Magnifying power 50 fold — with small horse-shoe-stand, sliding tube, micrometric screw, turning plain-mirror, diapbagm, 2 objective -lenses, achromatic ocular of 80 and 160 fold magnifying power, with pincette, testing-preparation, object- glasses & covering-glasses, in wooden-box — do. same as foregoing, but larger, with concave mirror, 2 objectiv- lenses, 1 achromatic ocular of 100 and 200 fold enlarging power. With accessories in box. With sliding tube — do. especially suitable for controlling meat and testing food. With 2 objective-lenses, 1 achromatic ocular of 100 and 200 fold magnifying power. — With accessories in wooden-box. — With sliding tube . . — do. same as before, the tube fitted with rack & pinion — do. Horse-shoe-Stand, micrometric screw, turning diaphragm, concave and plain mirror, 3 objective -lenses, 1 ocular. — Enlarging power 50 — 200 fold. — With accessories and wood-box — do. With Horse- shoe- stand, fine adjusting screw, with 3 objective- lenses and 2 oculars, concave and plain mirror. Enlarging power 30 to 300 fold. With accessories in box — do. With Horse -shoe -stand, fine adjusting screw, concave and plain- mirror, diaphragm, system No. 4 & No. 7, 2 oculars. Enlarging power 20 to 500 fold. — With accessories and box - • . . . 50. 50 10. — 20. 33. 27. 50 33. - 41. 25 82. 50 82. 50 78 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Compound Microscope. 1177, — With Horse-shoe- stand, rack- and pinion, fine adjusting screw at the table, concave and plain • mirror, diaphragm. May be folded. With 3 objective lenses and 2 oculars. Enlarging power 50 to 300 fold. With accessories and box 66. No. 1170. 1178. - With Horse-shoe-stand, Ihe mirror may be moved horizontally, with cyliodric diaphragms and micrometric screw at the tube. With systems 4, 7, 9 aod 3 oculars. Enlarging power 30 to 700 fold. With acce- sories and box 137. 50 1:5 No. IISO. 1179. — do. With Uorse-shoe-staud, mirror movable in horizontal direction, cylindrical diaphragm with sledge, micrometric screw at the column. — May be folded — Ocular-Micrometer '/so li"*"' system 4, 7, 10 and 3 oculars. Enlarging power 30—800 fold. — With accessories in box 225. 50 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn 79 Mk. Pf. Compound Microscope. 1180. — do. With Horse- shoe -stand, mirror movable in horizontal direction, cylindrical diaphragm with sledge, large rotating table, micronietric screw at the column. — May be folded — with ocular- micrometer, systems 4, 7, 9, 10 and 3 oculars. — Enlarging power 20— 1210 fold. — With accessories in box 352. — 1181. — do. as No. 1180, but with system No. 11 (immersion) and ocular No. 4. Enlarging power 20-2000 fold 885. — 1182. — Microscope for Lectures — to be used like a telescope, with 3 ob- jective-lenses and 1 ocular. Magnifying power 50, 100 and 150 fold 40. — 1183. — do. with 2 objective-lenses and 1 ocular. Magnifying power 30 and 100 fold 33. — 1184. 1185. 1186. 1187. 1188. 1189. 1190. 1191. 1:4 - . - '■^- No. 11S2 u. 1183. No. US5. — do. Kloenne's and Miiller's System, with large object, table turning around the column, 8 preparations may be placed at once on the table. With 2 objectives and 2 oculars. Magnifying power 30 — 600 fold 198. — Microscopical Case, containing: 1 microscope No. 1170, 1 preparing knife, 1 pair of bent scissors, 1 piocette, 2 glass-rods, 1 brush, 2 porcelain-dishes 12 covering glasses, 1 ground object-holder, 1 testing- object, 3 bottles with chemicals, 1 alcool-lamp, Canadiau-balm, asphalte- varnish, dest. water, benzine, caustic potash and alcool (in glasses with ground glass -stopper). With instruction for the use of the microscope and for making microscopical preparations. lu polished wood box 44. — Accessories and Utensiles for Microscopic Observation. — Reversing Ocular 16. 50 — Ocular - Micrometer, to be placed in any ocular, each millimeter is divided into teuths 4. — — do. the millimeter is divided into twentieths 6. 75 — Objective-Micrometer, 1 millimeter is divided into 100 'b 11. — — do. '/a -, ., 100 tn 16. 50 — do. v. „ „ 100 tb 22. — for 100 glasses 80 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Accessories and Utenslles for Microscopic Observation. 1192. — Lena for lightening on stand 5. — , 7. — , 10. 50 or 13. 25 1193. — Table for preparations, the preparations may be moved automatically. — Report on the Scientific Instruments on the Berlin -Industrial-Ex- hibition of 1879. Fig. 156 38. 50 1194. — do. the preparation may be moved automatically on two different ways — Report on the Scientific Instruments on the Berlin-Industrial- Exhibition 1879. Fig. 157 49. 50 1195. — Schultze's heating table for preparations, with thermometer .... 44. — 1196. — Compressorium 24. 75 Micro-Spectroscope see No. 1042, polarisation-apparatus for mi- croscopes see No. 1271 & 1272, Drawing-prisms see No. 1146—1151. 1197. — Object-holders I'/s X I'/s 2'/, XVt 3X1 in ch of Rhenish glass with ground- border 2. 50 3. — 3. 25 do. with polished border 4. — 5. — 6. 75 of finest plate-glass with ground edges 6. — 7. 25 10. 50 do. with polished edges 7. — 8. 50 12. 25 1198. — Glasses for preparations, dimpled with 12 3 dimples price 3. — 4. 50 5. 25 ML 1199. — Covering glasses of finest English glass, square 'U V. % :Vi._mch —.75 1. 26 1. 75 2. 25 Mk. for 50 pieces. 1200. — do. same, round % Vs Vg ^,a °/, in ch diameter 1. 75 2. — 2. 75 3. 50 4. 50 Mk. for 50 pieces. 1201. — Turning disk for making varnished rings on preparations 11. — 1202. — Labels for preparations. 100 — .60 1203. — Boxes, for 50 preparations of board of else-wood of mahogany-wood each 2. 75 4."^^ 5. — Mk. Larger Cabinetts of any size to order. 1204. — Preparing needles with ebony-handle wit h straight bent lancet- like harpon-like point 1. 25 1. 50 1. 50 1. 75 Mk. 1205. — Preparing knife with ebony-handle 2. — 1206. — Shaving knife 4. 25 1207. — Valentin's or Harting's double-knife 4. — 1208. — Scissors with straight- bent-point 2. — . 2. 75. Mk. 1209. — Microtome, for cuts of determined thikness and any wished fineness Micrometric screw with divided drum, glass-clock to make the cut, knife and box 22. — 1210. — Brass-Pincette — . 50, — . 75 or 2. — 1211. — do. of steel with polished points 1. 50 or 2. — 1212. — do. of steel with chanelled points and adjusting-slider with straight, with bent points 47= 5. — Mk. 1213. — Dust- and Varnishing-Brush 1. — 1214. — Glass-Rod —.25 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. Accessories and Utensiles for Microscopic Observation. 1215. — Case of instruments for making microscopical preparations, — : one Valentin's double knife, 2 preparing knives, 4 needles, 1 pincette, 2 scissors in leather box 8. 75 Ail chemicals for microscopic researclies will be supplied at lowest prices. Apparatus for Projection. 1216. Solar -Microscope, with achromatic lenses and heliostate, microscope tube of stout board, the body of the 'heliostate made of wood 82. 50 1217. — do., entirely of metal, with rack and pinion 165. — 1218. — do. with larger lenses and micrometric screw 200. — 1219. — do. same as 1218, but combined with apparatus for polarization, interference and diffraction of light — at prices varying from 275. — to 675. — 1220. 1221. 1222. 1223. 1224. 1225. 1226. 1227. 1228. No. 1228. Magic Lantern, in varnished tin-plate box, paraffine-lamp with round burner and silver-plated reflector, the lens with rack and pinion ad- justment Diameter of the lens 22 24 36 42 48 lines 25. — 277"50 337^^ 447"=^ 55, — Sciopticon, an improved Magic Lantern with double-flame paraffine burner, large lightening lenses and achromatic object lenses 130. — — do. with stand, serves also for the projection of physical and chemical experiments. — MuUer-Pouillet II. 1. Fig. 334 137. 50 — prolongating tube for the projection of microscopic objects, with object- table screw and pinion 50. — — prolongating tube for the projection of horizontal objects. Weinhold, Fig. 77 145. - — Prolongating apparatus for the Sciopticon, for projecting opaque bodies 82. 50 Projection Apparatus, same as No. 1221, but fitted with an automatically regulating arch, lamp for electric light 150. — — do. as 1222, but with an automitically regulating arch, light-lamp . 165. — — do. as 1222, but fitted with an incandescent lamp for electric light, may be turned, for horizontal and vertical projection 132. — 6 82 C. Gerhardt, Marquart's Lager chemischer Uteusilien, Bonn. Mk. Pf. Projections -Apparatus — do. as 1222, but with lime-light- lamp for oxygen, hydrogen and coal- gas — or oxygen and alcohol 154. — For producing the electric light I recommend Grove's or Bunsen Elements, and more especially my dynamo-electric Hand-Machine A. Iron-retort for making oxygen with tripod-stand and gas- or parafine-lamp 13. 25 or 16, 50 Apparatus for making hydrogen 8. —, 12. 50 or 84. — Glass-Gasometer with brass fittings 66. — — do. of varnished tin-plate 50. — 1229. 1230. 1231. 1232. 1233. No. 1232. i;l8 No. 1233. 1234. India-Rubber-Bag with cock, containing about 12 galloons 40. — 1235. — do., containing about 24 galloons 45. — 1236. Press for the Bags 16. 50 1237. — Curtain of Shirting, about 6 feet square 6. 75 1238. Frame for the Curtain 8. 25 The apparatus, which are especially fitted for projection, are mentioned at the respective chapters. Glass -Photographs for projection apparatus from all Scientific Branches as Physics, Astronomy, Mineralogy, Botany, Zoology, Gcograghy, ancient History etc.. Views of countries, cities, monu- ments, sculptureswill be supplied at a moderate cost. Telescopes. 1239. — small Gallilei's Telescope with achromatic object lens and concave ocular 8. 25 1240. — achromatic telescope with terrestrial ocular and 3—6 prolongating tubes, varying according to size from 13. 50 to 135. — 1241. — Telescope with brass-stand, may be used vertically and horizontally, with terrestrial and astronomic oculars, varying according to size and make from 66. — to 440. — 0. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 83 Mk. Pf. 1242. Open Model of a compound Microscope 11. — 1243. Open Model of Gallilei's Telescope 8. 25 1244. Open Model of an astronomic Telescope 8. 25 1245. Open Model of a terrestrial-Telescope 11. — No. 1242. 1246. Model of Newton's Mirror-Telescope 16. 50 1247. Model of Herschel's Mirror-Telescope 16. 50 1248. Model of a Brachy-Telescope 22. — 1249. Model of a Meridian-Circle, entirely of wood 50. — G. Interference and Difraction of Light 1250. Fresnel's Mirror -Apparatus, with 2 black plain -mirrors and micromctric screw with coloured glasses placed on a support, also with linear slit, upon seperate stand 53. No. 1260. 1251. Prism to show interference 13. 50 1252. — do. with stand and lens with seperate support 20. — 1253. Figeau's Interference Apparatus with support 33. — 1254. Billet's Lens with lens-cell and micrometer screw upon support .... 40. — Cylindric-Lens for producing a light-line see No. 978. 6* 84 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1255. Diffraction-Apparatus, consisting of an achromatic telescope with support, some slits, apertures and grates 94. — 1256. — do., more complete, the slit being fitted with micrometer screw and graduated screw-knob, also with glass-grate, double-grate, double slitetc. 230. — 1257. Diaphragm with one or more fine apertures, slits or double-slits, with frame, fitted for being adapted to the object lense of a telescope . . 5, 50 1258. IVIOvable Slit with exactly graduated micrometer screw, with frame, may be placed in front of the telescope-object lens 25. — 1259. Screen with stand and with turning diaphragm, with 6 different apertures and slits 13. 25 12G0. — do. on stand, with slit fitted with a fiue micrometer screw .... 27. 50 1261. Wire-grate, of different thickness from 1. 75 to 11. — 1262. Glass-grate, 1 Square Centimeter (about Vj Square Inch) divided into 100 150 200 250 300 400 10. — 14. 50 19. — 25. — 30. — 40. - 500 600 800 1000 1200 1600 50. — 60. — 66. — 74. — 80. — 90. — 3200 64 00 parts 100. ^ 132;"^= No. 1264. 1263. Grates photographed on glass, of different fineness . . . from 8. 25 to 33. 1264. Illustration of Newton's Coloured Rings, with brass-fittings and press-screw U. 50, 20. — , 26. 50 or 33. 1265. Eisenlohr's Mechanism for observing Newton's rings in thin pellicles at the surfaces of liquids, may be placed on the centrifugal machine ... 10. H. Polarization and double Refraction of Light. 1266. Simple Polarizing Apparatus, may be placed on the centrifugal machine. Muller-Pouillct II. 1. Fig. 406 — By means of this apparatus the diflercnce of polarized and not polarized light may be sliowu simul- taneously to a large number of pupils 22. 1267. — do. Duboscq's may be placed on front of a projection apparatus — Miiller-Pouillet II. 1. Fig. 407 22. 1268. Norremberg's Polarizing Apparatus, of simplest kind, consisting of a frame and 2 black mirrors, the upper of which may be turned 40. 1269. — do. with glass-clock-analysator 46. C. Gerhardt, Marquart's Lager chem. Uteusilien, Bonn. 1270. Mk. Pf. Nbrremberg's Polarizing-Apparatus, — do,, on mahogany-box with 1 black mirror, glass-plate-analysator, Nicol's prism, glass -table, holder for crystals, graduated disc and turning table, 2 lenses, 6 glasses (cooled), 6 crystals, 1 plaster- figure, 8 thin plates of gypsum, 1 gypsum -wedge, 1 quartz turning to left and to right, 1 press with 2 glasses, 1 glass-tube for fluids .... 200. — 1271. Lang's Microscopical Polarizing-Apparatus, with large field of view — Miiller-Pouillot II. 1. Fig. 505 20O. — 1272. — do. Hofmann's, complete. Miiller-Pouillet 11. 1. Fig. 506 165. — i:to No. 1277 1273. Dove's Apparatus to show Polarization, consisting of a stand with 4 sliding holders, graduated disc, black mirror, Nicol's prism, glass-press, crystal-holder with 4 cooled glasses and 3 crystals 165. 1274. — do., more complete, with 2 Nicol's Prisms, tube for liquids, 6 cooled glasses, 6 crystals, glass-press et cet.also with 7 sliding holders 275. — or 400. 1275. — do. Seebeck's model, with 2 black mirrors, one of which may be turned, with stand, 3 cooled glasses and glass-holder 33. — do. with graduated disc and Nicol's prism, with 3 cooled glasses, 3 crystals and glass-holder 94. — do. Mach'fl, with rotating aualysator. — Miiller-Pouillet II. 1. Fig. 513 with 2 Nicols prism, right-view-prism, quartz-plate, glass-press . . . 132. 1278. Lang's Projection Apparatus to show Polarization. — Miiller-Pouillet II. I. Fig. 511 160. 1276. 1277. 86 C. Gerliardt, Mavquart's Lager chemischer Utensilieu, Bonn. Mk. Pf. 1279. Soleil-Schcibler's Polarizing Apparatus for sugar-analysis, consisting of the complete apparatus witli scale graduated in 100 'bs. and nonius, magni- fying mirror, 2 observing tubes of about 8 and 4 Incii lengtii, in mahogany-box 425. — 1280. — do. with 4 observing tubes of about 24, 16, 8 and 4 Inch lenght . . 470. — 1281. Jelelt-Corny Half-Shade or Penumbral Polarizating-Apparatus with wedge- compensator, consisting of the complete apparatus with scale divided into 100 tlis. and nonius with magnifying mirror, 2 observing tubes of S and 4 Inch length, complete in mahogany-box 435. — 1282. Hoppe-Seiler's Polarizing Apparatus for analysis of saccharine and urine, with brass-column and two observiug tubes, complete in mahogany- box 250. — or 320. — 1283. — do. for the analysis of wines, which have be«n treated with saccharine (Gall's method), with an examiuing tube of 8 Inch length, complete with accessories and a mahogany-box 66. — 1284. — do. Mitscherlicb's with an observing tube of 8 Inch length .... 66. — 1285. — do. with a shadow-plate 127. 50 i;12 No. 1279. No. 1293. 1286. Wild's Polarlstrobometer, improved construction, with 3 observing- tubes of 9, 8 and 4 Inch length, alcool-or gas-lamp fitted for homogeneous light, with telescope- indicator, complete iu a mahogany-box .... 346. — 1237. — do., smaller and more simple, with 2 oh serving-tubes of 1 and 2 Inch length, with magnifying glass 160. — 1288. Observing Lamp, for oil and paraffine with glass- and clay-cylinder ... 15. 50 1289. — do. for gas 17. 50 1290. Observing tubes with frame, covering-glasses and India-Rubber-rings long 1 2 4 8 16_ 2 4 Inch. of glass 10. — 10. — 10. — 10. — 11. — 13. 25 Mk. 1291. — of brass U. — 11. — 11. — 11. — 12. — 15. — Mk. 1292 Stiihrer's Polarizing Apparatus fitted for the Sciopticon — Wcinhold, Fig. 293 110. — 1293. Turmalin-Tongs with 2 turmalio -plates, to show the coloured rings in crystal-plates 13. 50, 20. — or 26. 50 1294. — do. same, arranged in such manner, that the turmalins may be moved in long parallel liuc from another 30. — 1295. — do. Bertin's, with lens-system for a large field of view, and with graduated polarizer 60. — C. Gerhardt, Mar quart's Lager chemischer Utensilien, Bonn. 87 Mk. Pf. 1296. Bablnet's Compensator, in brass-frame, with raclc and pinion and with graduated ciicle 105. — 1297. Fresnel's Parallelepiped, with frame 26. 50 or 40. — 1298. Loyd's Apparatus for conical refraction 24. 50 1299. Bresina's Stauroscope 82. 50 1300. Glass-Press to press the glass 13. 25 or 16. 50 1301. — do. for bending the glass 13, 25 or 16. 50 Crystal-Plates in cork-frames. 1302. — (with one axis) positive, ground in a line perpendicular to the axis, amethyst, prussiate of potash, brucit, dioptas, parisit, quartz, smoke- quartz, hyposulfite of potash, tin-stone, zirkon etc. from 2. 75 to 20. — 1303. — Crystals with one axis, negative: Arragonit, Beryl, Calcareous Spar, Kalium, Copper, Chloride, Cyanure of Potash, Chlorate of Potash, Phosphate of Amonium, Rubin, Saphire, Nitrate of Soda, Sulphite of Nickel, Emerald, Turmaline et cet from 1. 75 to 16. 50 1304. — Crystals with two axis : Adular, Arragonit, Baryte, Borax, Bichromate of Potash, Glauberit, Mica, Gypsum, Nitrate of Potash, Sulphate of Copper, Hyposulphite of Soda, Tartrate of Potash, Sugar et cet from 1. 75 to 16. 50 1305. Niool's Prisms, size ab out 2 3 5 7 1 lines price 6. 50 10. — 20. — 40. — 77. — Mk. size about 12 14 lines price 120. — 176. — MkT" 1306. Rhomboids of Calcareous Spar, size ab out % 1 IVs IV, 2 Inc hes price 16. 50 22. — 29. — 50. — 72. — Mk. 1307. Dies of Calcareous Spar, perpendicular and parallel to the axis 13. 25 to 22. — 1308. Plate of Calcareous Spar, between 2 glass prisms, showing from one side rings and from the other side the double refraction .... 8. 25 to 16. 50 1309. Arragonit, showing both system of rings without polarizing apparatus 13. 25 to 22. — 1310. Double Plate of quartz turning to the left and right 10. — 1311. Thin Plate of mica for observing Talbot's lines 8. 25 to 16. 50 1312. Collection of 7 plates of quartz, showing the colours of the' Spectrum, from 33. — to 55. — 1313. Weci^s of Gypsum 16. 50 1314. Plates of Gypsum of '/,, ^^ and "/« length of wave, — 13 different re- tartations of waves may be produced by superposing alternatively one plate upon the other, with brass-frame, price per set from 13. 25 to 27. 50 1315. Plates of Mica — of '/, undulation — serve for examining the double refraction in single-axis-crystals 2. 25, 3. 30 or 5. 50 1316. Noerrenberg's Combination of Mica- Plates, for showing, how single-axis- mica is produced from a two-axis-one set of 6 pieces 27. 50 88 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Y. Heat. Mk. Pf. A. Extension by heat. 1317. Cylindrical Vessel for determining the freezing - point on thermometers. Miiller-Pouillet II. 8. Fig. 3 with a filled thermometer-tabe 8. 25 1318. Apparatus for determining the boiling point, witli fiUed-thermometer-tube. — Miiller-Pouillet II. 2. Fig. 4 6. 7.5 1319. — do., with double walls, manometer and filled thermometer -tube. — Muller-Pouillet II. 2. Fig. 5 16. 50 1320. Standard-Thermometer with opal-glass-scale + IOC Celsius each degree is divided into '/s ° 20. — each degree is divided into '/io° 26. 50 1321. Chemical Thermometer with scale edged on the tube, graduated into '/i° from — 10 to + 100 ° to 250 ° to 300 » Celsius 5. 50 6. 75 8. 25 Thermometers for usual purposes, window-thermometers, house- thermometers etc., filled with mercury or alcool, are supplied in various patterns and at wholesale prices. — See also chapter Metereology. 1322. Reaumur's, Celsius' and Fahrenheit's Thermometer. Scale, on wood, with opal glass-scale 4. — 1323. Small Thermometer with plate -glass -scale, the numbers written inverted for the Sciopticon 4. 50 1324. Muschenbrock's Lever - Pyrometer, simple. Miiller - Pouillnt II. 2. Fig. 8, 9 10. — or 13. 25 1325. — do., with 3 different rods of metal and with alcool lamp . 26. 50 or 40. — C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 89 Mk. Pf. 1326. — do., in finest execution, with mirror, suitable for exact measuring. — Miiller-Pouillet II. 2. Fig. U. — with oil bath 50. — 1327. Apparatus for determining tlie co-efficient of extension, with 6 different metal -rods 27. 50 or 44. — 1328. — do., Weinhold's model, with 3 metaltubes, each 3'/s feet long fitted for the Sciopticon. — Weinhold, Fig. 303 66. — 1329. — S'Gravesande's Pyrometer, to show the extension of solid bodies. — Consisting of ball and ring, of metal 5. — 1330. — do., with stand and lamp . . . '. 16. 50 No. 1332. 1331. Apparatus for showing fbe action of steam in steam-engines . . 4. — or 5. 50 1332. Tyndall's Apparatus for showing ttie violent contraction produced by the cooling of heated bodies. — Miiller-Pouillet II. 2. Fig. 16 — with alcool-lamp ^^- — 1333. — do., with 4 Bunsen-burners (Fig. 1339) 25. — I c No. 1339. 1334. Strips of Iron and brass, riveted together, to show the unequal extension of these metals 2. 75 1335. Model of a rust pendulum — MuUer-Pouillet II. 2. Fig. 18 from . 10. — to 27. 50 1336. Hermann & Fister's Metal -Thermometer, with maximum- and minimum- indicator. — Miiller-Pouillet II. 2. Fig. 21 35. — 1337. — do., with electric contact o 40. — 1338. — do., shape of a watch, in nickelled case 33. — 1339. — do., Breguet's, with spiral of platinum, gold and silver. — Muller- Pouillet II. Fig. 2.S 33. - 1340. — do., with hold-screws for the galvanic current 40. — 90 C. Gerhardt, Marquart's Lager chemischer Dtensilien, Boim. Mk. Pf. Apparatus for determining the co-efficient of the extension of mercury — Weiohold, Fig. 306 .. . 50. - — do , Dulong & Petits, suitable for exact measurings, with Itathetometcr. — Miiller-Pouillet II. 2. Fig. 28 275. — 1341. 1342. 1343. 1344. 1345. 1346. 1347. 11. 50 2. 75 5. 50 Regnault's Dilatometer. — Miiller-Pouillet II. 2. Fig. 32 Weight Thermometer, simple. Miiller-Pouillet II. 2. Fig. 33 — do., Gay-Lussac's- MuUer-Pouillet II. 2. Fig. 34 Water-Thermometer, with graduated scale and comparing scale 13. 25 Glass-Cylinder witli 2 lateral thermometers and one vessel for ice, serves for showing the stratification of water according to its specific weight. Miiller-Pouillet II. 2. Fig. 47 9- — 1348. Apparatus for determining the greatest density of water. — Weiuhold, Fig. 307 — 20. — 1349. Cold-Water-Swimmer. Ball of brass, which swims in cold water and sinks down in warm water 2. 75 or 5. — 1350. Mechanism for showing the circulation of heated water, consisting of a glass-tube bent in a right angle 7. 25 1351. — do,, smaller and on stand, with lamp and fitted for projection ... 5. — 1352. Apparatus for showing the extension of air, if submitted to a constant pressure. VVcinhold, Fig. 311 33. — 1353. — do., fitted for projection. — Weinhold, Fig. 310 20. — 1354. — do., Regnault's, for exact measurings. — Miiller-Pouillet It. 2. Fig. 57 132. — 1355. Apparatus for determining the co-efficient of the extension of gases, if submitted to a constant pressure 10. — 1356. — do., combined with Feilitzsch's Apparatus for proving Mario ttc's law, serving at same as air-thermometer 22. — C. Gerhardt, Marquart's Lager chemisclier Utensilien, Bonn. 91 Mk. Pf. 1357. Jolly's Air-Thermometer, simplest construction on wood-stand 72, — 1358. — do., Pfaundler's improved system, on an iron stand. — Miiller- Pouillet II. 2. Fig. 73 115. — 1359. — do., Weinhold's, especially suitable as demonstratiug-thermometer for schools — "Weinhold, Fig. 313 176. — 1360. — do, Riess's — Weinhold, Fig. 421 — ; . . 44. — 1361. — do , Rudberg's — Miiller-Pouillet II. Fig. 64 60. — 1362. Leslie's Differential-Thermometer. Miiller-Pouillet II. 2. Fig. 76. 5. — or 11. — 1363. Schumann's do. The balls of this differential-thermometer are sur- rounded by vessels, which serve for receiving liquids. — With special instruction 19. 50 1364. Rumford's Differential-Thermometer. — Miiller-Pouillet II. 2. Fig. 77 . . 11. - 1365. Dufour's DifTerentlal-Thermometer for demonstrating purposes. — Journal de Physique 83 pag. 321. — Zeitschrift fiir Instrumentalkunde 1884 Heft 2. — 40. — 1366. Pfaundler's Double-Vessel-Air-Thermometer. MuUerPouillet II. 2. Fig. 79. 11. 50 1367. Glass Balloon with stop-cacl( for determining the specific weigth of gases MuUer-Pouillet II. 2. Fig. 81 16. 50 B. Changes of the State of Aggregation. 1368. Freezing-Thermometer on stand 8. 25 or 16. 50 1369. — do., smaller and with a transparent scale for projection 20. — 1370. Hugi's Apparatus for proving, that freezing of water may be retarded by pouring oil on the surface. Miiller-Pouillet II. 2. Fig. 86. 8. 25 92 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1371. Small Rod of Wood's Metal — melting at about C5« Gels 2. 25 1372. Iron-Sprinkling-Ball to show, that freezing water changes its volume . . 2. 50 1373. Moussons Apparatus for proving, that ice at low temperature may be made liquid by strong pressure. — Miiller-Pouillet II. 2. Fig. 93 40. — 1374. Grubeaud's Freezing -Apparatus, to be experimented with by dissolving Nitrate of Amonium. Miiller-Pouillet II. 2. Fig. 102 55. — 1375. Apparatus for showing the elasticity of different vapours, consisting of 3 barometer -tubes with stand and mercury- trough. — Miiller- Pouillet II. 2. Fig. 102 55. - 1376. Apparatus for showing the difference of gases and vapours. — Miiller- Pouillet II. 2. Fig. 193 27. 50 1377. Steam-Barometer, Apparatus for measuring the elasticity of saturated steam of water at different temperatures. — Weinhold, Fig. 317 . . 30. — 1378. 1379. 1380. 1381. 1382. 1383. 1384. 1385. 1386. 1387. 1388. 1389. Dalton's Apparatus for measuring the elasticity of saturated steam of water at temperatures between 0° and 100* — Miiller-Pouillet II. 2. Fig. 115 60. — — do., Gay-Lussac's for measuring the elasticity of vapours under 0" . 53. — — do., Schmidt's for determining the elasticity of water vapours below the boiling temperature 22. — — do., Regnault's for the temperatures from 0° — 50". — Miiller- Pouillet II. 2. Fig. 120 165. — — do., Magnus's. — Miiller-Pouillet II. 2. Fig. 119 200. — — do., Weinhold's, for measuring the elasticy of steam in a space filled with air — for ethereous vapours. — Weiohold, Fig. 325_ — .... 16. .'iO — do,, Weinhold's, for measuring the elasticity of steam in a space filled with air — for steam of water. — Weinhold, Fig. 326 11. 50 Papin's pot, iron made 8. 25 or 13. 25 — do., made of copper, with thermometer, safety-valve and tripod-stand 40. — — do., same as 1386, but with a manometer 53. — Apparatus for showing the equilibrium of the elasticity of vapours in communicating vessels which are heated in unequal manner. — Miiller-Pouillet II. 2. Fig. 127 U. 50 — do., with stand 20. — C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1390. Gay-Lussac's Apparatus for proving Dalton's Principle, that saturated steam has the same maximum of elasticity in a space filled with gas, as in the vacuum 16. 50 1391. — do., with stop-cock. - Miiller-Poaillet II. 2. Fig. 128 25. - 1392. — do.. Prick's, Miiller-Pouillet II. 2. Fig. 130 8. 25 1393. IVtechanism for determining the boiling point of fluids, with thermometer — Miiller-Pouillet II. 2. Fig. 135 8. 25 1394. Apparatus for demonstrating Leydenfrost's essay, consisting of a platinum- cup with stand 20. — 1395. — do , with a copper-cup 13. 25 1396. Liebig's Cooling Apparatus, made of glass. — Miiller-Pouillet II. 2. Fig. 139 13. 25 or 22. — 1397. — do., of brass 18. - , 27. 50 or 33. — 1398. Ice-Apparatus, for making ice in a rarefied space by means of uther 1. 75 or 2. 50 1399. — do., Leslie's, for making ice in a rarifled room by means of sulfuric acid. — Miiller-Pouillet II. 2. Fig. 140 4. — 1400. — do., Weinhold's, serves also for explaining Carre's Ice -Machine. — Weinhold, Fig. 348 — 22. — 1401. — do,, as 1400, but with stand and thermometer 33. — 1402. Carre's Sulfuric- Acid- Ice-Machine, with air-pump. — Miiller-Pouillet II. 2. Fig. 141 — from 175 to SCO. — 1403. — do., for ammonia-gas. — Miiller-Pouillet II. 2. Fig. 146 with furnace and cooling-vessel from 55. — to 165. — 1404. Wollaston's Kryophor. — Miiller-Pouillet II. 2. Fig. 142 2. 50 1405. do , with cylindrical condensating-vessel. — Weinhold, Fig. 350 .... 2. 50 1406. Water-hammer. — Frick, Fig. 842. — I. 75 or 3. 50 1407. Pulse-Hammer. — Fric',c, Fig. 844 1 — or 1. 75 1408. Gay-Lussac's Apparatus for determining the density of vapour. -- Miiller- Pouillet II. 2. Fig. 147 53. — 1409. — do., Hofi'mann's, complete with cooling apparatus and mechanism for minute reading. Miiller-Pouillet II. 2. Fig. 148 82. 50 1410. — do., Dumas's — Miiller-Pouillet II. 2. Fig. 150 33. — or 44. — 1411. Weinhold's Apparatus for the essays with saturated and over-heated steam — Weinhold, Fig. 321 72. — 1412. Weinhold's Apparatus showing that ice evaporates, when being in vacuo — Weinhold, Fig. 352 11. — 1413. — do. with heating by means of the galvanic current — Weinhold, Fig. 353 16. 50 1414. Natterer's Compression-Apparatus, for compressing carbonic acid — with 2 bottles essayed at 130 atmospheres — Miiller-Pouillet II. 2. Fig. 156 715. — 1415. Andrew's Press for condensing gases, for projection, Weinhold, Fig. 327 22. — 1416. Tube filled with liquid carbonic acid — the quantity of carbonic acid is so small, that the tube appears empty at usual temperature and that the liquid carbonic acid becomes only visible, when cooling .... 16. 50 1417. — do. containing 2—5 Cubic Centimeter liquid carbonic acid at usual temperature and appearing empty again, if warmed with the hand . 22. — 94 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Tube filled with liqult carbonic acid 1418. — do. half filled with carbonic acid, to show the great movableness of the liquid 22. — 1419. — do. containing so much carbonic acid, that the latter fills the whole tube, when heated to 25° Celsius 33. — 1420. Faraday's Mechanism to maice mercury freeze in a glowing crucible by means of condensed carbonic acid — Miiller-Pouillet II. 2. Fig. 162 20. — or 50. — 1421. Apparatus to make mercury freeze by means of liquid sutphurous acid — Weinhold, Fig. 361 16. 50 1422. — do. Weinhold, Fig. 362 13. 25 1423. Moulds for the recongelation of ice, of box-wood in iron-trimming, in form of cylinders, balls or cups, Weinhold, Fig. 363, 354 and 365 ... . 16. 50 1424. Weinhold's Mechanism for fusing a loaded wire by means of an ice-block 22. — C. Calorimetry. 1425. Tyndall's Apparatus to prove the relative warmness of diiferent metaUs, with 5 different balls — Miiller-Pouillet II. 2. Fig. 173 11. — 1426. — do. Weinhold's Fig. 343 22. — 1427. Lavoisier's Ice-Calorimeter. — MuUer Pouillet II. 2. Fig. 179 . 40. — or 50. — 1428. — do. Bunsen's. Miiller-Pouillet II. 2. Fig. 176 13. 25 1429. — do. Reichert's for lectures. Carl's Rep. XII. pag. 77 55. 1430. Weinhold's Calorimeter, with warming vessel and testing ball. Weiahold, Fig. 344 & 345 7. __ 1431. Double Calorimeter. — Demonstrating Apparatus to compare rapidly the specific warmness of two bodies, with 2 thermometers graduated into '/,„" 82. 50 1432. Regnault's Steam-Heating-Apparalus. — Miiller-Pouillet II. 2. Fig. 179. . 22. — 1433. — do. serves for larger quantities. Miiller-Pouillet II. 2. Fig. 182 . . . 275. 1434; do., Neumann's. Muller-Pouillet II. 2. Fig. 184 66. — 1435. Kopp's Apparatus for determining the specific warmnes of liquids by means of the mixing method — Miiller-Pouillet II. 2. Fig. 186 and 187. . . 33. — 1436. Andrew's Calorifer, modified by Pfaundler — Muller-Pouillet II. 2. Fig. 192 6. 75 1437. Pfaundler's Apparatus for determining the specific warmness of liquids by means of the electric current. — complete with 2 thermometers divided into '/,„». — Muller-Pouillet II. 2. Fig. 193 215. — 1438. Favre & Silbermann's Mercury-Calorimeter — Muller-Pouillet II. 2. Fig. 194 116. — 1439. Dulong & Petit's Apparatus to determine the specific warmness by means of the cooling theory — Miiller-Pouillet II. 2. Fig. 196 40. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 95 Mk. Pf. U40. Weinhold's Apparatus for the calorimetric measuring of high temperatures. — MuUer-Pouillet II. 2. Fig. 197 and 19S 60. — 1441. De la Roche & Berard's Apparatus to determine the specific warmness of gases submitted to a constant pressure. — Miiller-Pouillet II. 2. Fig. 199 165. - or 330. — 1442. Clement & Desormes's Apparatus to determine the specific warmnes of gases, when their volume remains constant. — Miiller-Pouillet 11. 2. Fig. 203 27. 50 1443. Brix's Apparatus for determining the eraporating warmness of vapours. — Miiller-Pouillet II. 2. Fig. 203 - 33, — 1444. Berthelot's Apparatus for determining the whole warmness of steam. — Miiller-Pouillet II. 2. Fig. 210 40. — 1445. Favre & Silbermann's Calorimeter for the assays about the heat of com- bustion — Miiller-Pouillet II. 2. Fig. 211 160. — D. Heat and Work, 1446. Apparatus for proving that temperature changes, when gases expand or are compressed — Weinhold, Fig. 368 44. — 1447. Favre & Silbermann's Apparatus for showing, that rapidly compressed air grows warmer and that it cools, when it expands suddenly — with a sensitive metal-thermometer 150. — 1448. Compression-tinder-box with metal-sucker — Miiller-Pouillet II. 2. Fig. 225 5. — or 6. 75 1449. — do., withastrongmetal-suckcr. — Miiller-Pouillet II. 2. Fig. 227 10.— or 16. 50 1450. Tyndall's Apparatus to malie water er ether boil by rubbing — Fitted for the centrifugal machine 4. 50 or G. — 1451. Puhy's Apparatus for determining the mechanic equivalent of warmness — Muller-Pouillet II. 2 Fig. 230 — with swinging engine Papiu's Vapour-Piston see No. 1331 100. — 1452. Glass-Model for explaining Newcoman's Steam-Engine 40. — IModels of steam-engines parts of machines et cet. see No. 587 and following numbers. 1453. Steam- Reaction-Wheel of copper, with stand and spirit-lamp 16.50,22. — or 33.— 1454. Heron's rotating ball, entirely of glass. Frick, Fig. 867 3. 25 1455. Eolipile with safety-valve 10. —, 13. 25 or 20. — 1456. Steam-ferry, small glass-model of Rchaeffer's pattern, moving upon water by escaping steam 22. — 1457. Fire-fountain, Heron's ball of copper with stop-cock, to be filled with spirit - Frick, Pig. 908 13. 25 96 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn, Mk. Pf. Propogation of Heat 145S. Ingenhousz's Apparatus for showing the conduction of the heat in different rods. — MuUer-Pouillet II. 2. Fig. 264 6. 75, 1 1. — or 20. — 1459. — do., on stand. — "Weinhold, Fig. 339 27. 50 1460. — do., smallfir fitted for the sciopticon 20. — 1461. Tyndall's Apparatus for showing that heat propagates unequally in copper and iron. — MiillerPouillet II. 2. Fig. 265 — with stand 20. - 1462. Davy's Safety-Lamp. — Miiller-PouiUet II. 2. Fig. 268 8. 75, 13. 25 or 22. — 1463. Depretz's Apparatus for showing that temperature diminishes in proportion to the distance of the heating source. — with 7 thermometers and a lamp — MuUer-Pouillet II. 2. Fig. 270 66. — 1464. — do., with 5 thermometers and a lamp 60. — 1465. — do., smaller, with 3 thermometers, for objective demonstration ... 40. — 1466. Apparatus for essays about the conducting power of different liquids. — Weinhold, Fig. 341 — with stand and thermometer 13. 25 1467. Mechanism for showing that liquids have little conducting power — Miiller- PouiUet II. 2. — with thermometer 10. — or 13. 25 1468. Grove's Apparatus for comparing the conducting power of two different gases. — MuUer-Pouillet II. 2. Fig. 577 — 22. — 1469. Magnus's Apparatus for determining the conductibility of different gases — MuUer-Pouiliet 11. 2. Fig. 278 16. 50 1470. Gypsum -Plate for showing the elUptic propagation of heat in crystals, with conducting wire — Weinhold, Fig. 340 1. 75 1471. Concave Mirror for the essays about radiant heat, mounted on stands with coal-and sponge holder Diameter IL 13^ 15^ 19. Inch one pair, brass, made 60. — 66. — 94. — 120 — „ nickelled 66. — 7 5. — 103. — 132. — „ german-silver 72. 50 88. — 110. — 154. — 1472. Hat of platinum net, to place on Bunsen'a burner, for essays about radiant heat. — Weinhold, Fig. 331 1. 50 1473. Thermosoop, simple air-thermometer. — Weinhold, Fig. 332 2. 75 1474. IMelloni's Thermo - Multiplicator, consisting of an else-wood-board, long 3'/, feet, with graduated rail and the following accessories! 6 stands with heavy foot, which may without difficulty be taken from the to be risen or lowered. 1 Locatelli's brass-lamp. 1 Copper- die. 1 alcool-larap with platinum-spiral. I copper-wire. 1 table for Locatelli's lamp. 1 table. C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 97 Mk. Pf. Melioni's Thermo-Multipllcator. 1 rock-salt-prism. 1 simple screen with square opening. 1 screen with adjusting slit and micrometer -screw. 1 double-screen with hinge. 1 screen with 5 adjusting apertures 1 stand with vertical mirror turning round its axle, with hori- zontal graduated circle an-d indicator, turning scale at the foot of the stand. 1 holder for the glass-plates. 1 thermo-pile with funnel and cylindric tube. 1 Bertram's Galvanometer. 1 double screen withont hinge. This apparatus in finest execution 340. — 1475. — do., more simple 285. — The parts may also be obtained single at following prices. 1476. 1 Stand with heavy foot and column 6. 75 or 8. 25 1477. 1 Locatelli's lamp with parabolic or spherical mirror 11. — or 15. 50 1478. 1 Copper dice, 1 side polished, 1 side white, 1 side rough, 1 side black 5. 50 or 8. 25 1479. 1 Table for Locatelli's lamp 2. 75 or 4. 50 1480. 1 Alcool-Lamp with platinum- spiral 2. 75 or 4. — 1481. 1 bent copper wire 2. 25 or 3. 50 1482. 1 table to place several objects upon 3. 25 or 5. 50 1483. 1 rock-salt-prism 13. 25 or 20. — 1484. 1 simple screen with square opening 3. 25 or 4. 50 1485. 1 screen with adjusting slit and micrometer-screw 8. 25 or 11. — 1486. 1 double screen with hinge 6. 75 or 9. — 1487. 1 stand with 5 adjusting apertures 8. 25 or 11. — 1488. 1 stand with turning scale at the foot, vertical mirror turning round its axle, graduated horizontal circle with index, turning scale at the foot of the stand 37. — or 51. — 1489. I holder for glass-plates 2. 50 or 3. 50 1490. 1 Thermo-pile with funnel and cylindric tube 33. — or 44. — 1491. 1 Bertram's Galvanometer 33.— 72. 50 1492. 1 double screen without hinge 4. 50 6. 75 1493. 1 steam-capsule, brass-made. — VVeinhold, Fig. 333 3. — or 5. — 1494. 1 flat-vessel, filled with a solution of iodine and bi-sulphuret of carbon, on stand. — Weinhold, Fig. 334 5. 50 1495. 1 brass-tube, closed on both sides by plates of rock - salt, serves for conducting gases G. 75 or 10. — 1496. Rock-salt-lenses, diameter 1—2 Inches U. — to 27. 50 1497. Rock-salt-plates, according to size and purity . 6. 75 to 27. 50 1498. Alum-plates, diameter 1-2 lines 4. 50 to 6. 75 1499. Plates of citric acid 3. 25 to 5. oO 7 98 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1500. Plates of gypsum, ground and not ground 2. 75 to 5. — 1501. — „ calcareous spar 2. 75 to 8. 25 1502. - „ mica 2. 75 to 5. — 1503. — „ agate 3. 25 to 5. — 1504. — „ quartz 8. 25 to 13. 50 1505. — „ sal-ammoniac 4. 50 to 6. 75 1506. — „ Iceland crystal 5. — to 8. 25 1507. — „ sugar 3. 25 to 5. — 1508. Coloured glasses with ground edges, 4 Inch square 60. — 1509. Plate-glasses, not coloured, with ground edges 4 Inch square 60. — Thermo-EIectric Piles see chapter Thermo-Electricity. 1510. Concave lens filled with a solution of jodine and bi-sulphuret of carbon, for showing that dark rays penetrate trough the solution. Weinhold, Fig. 335 33. — 1511. Tin-foil-screen with brass-frame, for the absorption of the caloric rays. Weinhold, Fig. 338 5. 50 1512. Croocker's Radiometer with wings blackened on one side. — Miiller- Pouillet II. 2. Fig. 300 9. — 1513. — do., with 2 superposed wheels, turning opposite to another .... 11. — 1514. — do., with a fixed metal-disk and two not blackened mica- balls turning upon it 16. 50 1515. — do., with blackened wings and one metal-disk turniag in opposite direction 20. — 1516. — do., with a platiua-wire-ring, which can be heated by the galvanic current 22. — YL Ma A'uetism. 1517. Load stone natural one pound 9. 1518. — do, caped and with anchor, prices varying to capacity of bearing (Figur No. 1518' from 16. 50 to 85. 1519. Load-Stones, from best Wolfram-Steel length ab out 4, 6, 8, 10, 12 Inch price 1. 2.i 1. 75 2 25 3. 50 5. — C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 99 Mk. Pf. 1520. Two Load-Stones with anchors and several rods of soft iron, with box Length of the rods about Inch 4, 6, 8. 12, 1 6 price 6.50 10.— 12.— 20.— 27.50 1521. Coulomb's Magnetic Store-House. — Mttller-Pouillet III, Fig. 19, long — 12 Inch, caped and with 3 sheets 20. — 1522. — do., with 6 sheets 40. — 1523. — do., with 9 sheets 60. - 1524. Horse-Shoe-magnets. Stone with anchor Number of the sheets 4 Length 6 of the sides 8 10 12 1 1.75 2.75 4.50 8.25 13.25 3 11.- 16.50 22.- 27.50 33.- 5 16.50 27.50 33.- 42. - 50.- 7 25.— 40.— 46.- 53.- 66.- Rods and Horse-Shoe-magnets will be supplied of best wolfram- steel in any wished size and form. No. 1526. 1525. Jamln's Foil-magnets : Number Length of Sides of foils. 8 Inch 12 Inch 10 16.50 27.50 15 25.- 39.- 20 27.50 50.- 25 40.- 62.- 30 53.- 82.50 1526. Compass-Needles in form of rhombs long about 2. 4. 10 Inches with brass-caps 1.50 2.25 2.75 4.25 5.50 „ agate-caps 2.25 3.23 4.- 5.50 7.25 1527. Brass-Stand for Compass-Needles with steel-point 1528. — do., of wood with steel-point 1529. — do., Lamont's with glass-swimmer 1530. Iron-and Steel-Rods for essays about magnetic distribution, 4 of soft iron & 4 of steel, long 10 lines, diameter '/^ Incli _ 1. 10 12. — 4. — 100 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1531. Rod of soft Iron, long 3'/i foot, to prove the terrestrial magnetism . . 5. — 1532. Apparatus for showing the distribution of magrelism in magnets — consisting of 24 small magnets suspended on points 26. 50 1533 — do., consisting of 18 small electro-magnets, turning single on points, with glass-plate and stand 50. — 1534. Two Glass-Plates, upon which small rod-and horse-shoe-magnets are cemented, for the demonstration of the magnetic curves 12. — 1535. Iron-Pcwder, filings one pound 2, 25 1536. — do., most finely divided 4. — 1537. Needle on stand to show declination, with graduated circle 13. 50 1538. Pocket-Compass-Needle in form of a watch 1. 75 to 7. — 1539. Marine-Compass-Needle with Cardanian Suspension . . . from 16 50 to 50, — 1540. Declination-Box-Compass with diopter and laying-down-needle 50. — 1541. A Pair of Astatic Needles from 3.50 to 12. — 1542. — do., on stand from 6.75 to 16. 50 1543. — do., larger, to be adjusted and with stand 20. — 1544. Inclination-Needle with fork for suspending. — Miiller-Pouillet III. Fig. 34 6. — 1545. — do., on stand 8. 25 or 11. — 1546. — do., with graduated circle 16. 50 1547. Inclination and Declination-Needle, to be used also as galvanoscope ... 22. — 1548. — do , with graduated circle (inclinatory and declinatory) 31. — 1549. — do., with 2 graduated circle and adjusting micrometric screw. ... 40. — 1550. August's Universal Compass-Needle, for declination and inclination, with silvered graduated circle 44. — 1551. — do , without graduated circle, quite simple 16. 50 1552. Magnetic Inclinatory. — Miiller-Pouillet III. Fig. 35 105.— or 132. — 1553. Leyser'sMagnetometer with mirror — Miiller-Pouillet III. Fig. 44. 110. — or 175. — 1554. Lament's Magnetic Theodolite for the Journey. — Miiller-Pouillet III. Fig. 46 205. — 1555. Coulomb's Turning Scale for showing the principles of magnetic attraction and repulsion — with round glass-vessel and engraved scale 50. — or 66. — 1556. — do., with mirror 66. — or 82. 50 1557. Weber 8 Apparatus for determining the full effect of magnets. — Consisting of a scale long I'/i, yard, with sliding box-compass and load-stone — MiillerPouillet III. Fig. 64 31. — C. Gerhardt, Marquart's Lager chem. Utensilieu, Bonn, 101 Mk. Pf. 1558. Apparatus for determining tlie intensity of terrestrial magnetism — with 1 small heavy load-stone. — Miiller-Pouillet III. Fig. 66 78. — 1559. Gauss's Bifiiar-Magnetometer, for detormiDlDg how the intensity of terrestrial magnetism variates 330. — or 500 — 1560. — do., with stopper 500. — 1561. Dove's Magnetic top 16. 50 or 22. — yil. Electricity. Frictional-Electricity, Voltaic Electricity, Thermo-Electricity. Induction, Electro-Magnetism, Diamagnetism, Dynamic-Electricity. No. 1562 No. 1563. 1562. Electrical -Maclilne, Winter's System, with ring and exciter, best make, diameter of the disk about Inch 8. 10. 12. 15. 20. 24. 25. 27. 33. -, 50. -, 60. -, 82. -, 105. -, 120. -, 150. -, 200. - 1563. — do., without ring and without exciter, simple make diameter of the exciter lach 8. 10. 12. 15. 20. 24. 25. 27. 94. 132. 165. - 27. 50, 35. -, 42. -, 54. -, 72. 1564. — do., Ramsden's, with 2 conductors and 2 pairs of rubbing cushions, best make diameter of the discs: 20. 24. 25. 27. 30. Inches price: 275. -, 385. -, 440. -, 500. -, 6G0. 102 C. Gerhardt, Marquart's Lager chem. UtensilieD, Bonn. 1565. Holtz's Electrical -Machine (Influence Machine), with frame of polished elsewood, without India-Rubber-Stand for the sucliing arma and without electrodes, simple make, diameter of the turning discs: Inch 10. 12. 16. 18. Mk. Pf. 20. price: 40. — , 60. — , 88.- 126.- 1566. do., best make, with India-Rubber-Standa for the sucking arms, with electrodes, frame of polished mahogany or walnut diameter of the turniD!; disc: Inch 10. 12. 16. 18. 140.— 20. price: 60. -, 82.50, 110.—, 155.- 205.— No. 1565. 1567. — do., Topler's Self-exciting Machine, simple make diameter of the turning disc: Inch 10. 12. 16. 18. 20. 1568. — do., best make price: 44.-, 66.-, 120.-, 165.— 210. 82.50, 132.-, 165.-, 210.-, 250. No. 1572. 1569. — do,, Leyser's — Weinhold, Fig. 399 127 50 1570. Wafer-Influence-Electrical- Machine — Weinhold, Fig. 390 33 — 1571. Armstrong's Steam -Electrical -Machine length of the boiler 38 Inches, diameter 17 Inches ' 55Q _ Accessories for Electrical -Machines: 1572. Apparatus for piercing ice 6. — or 11 — 1573. — do., for the essays about bound electricity 16. 50 or 20. — 1574. - do., to show the electric action of points — Frick, Fig. 607 5. 50 or 8. 25 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 103 Mk. Pf. Accessories for Electrical Machines 1575. — Griiel's apparatus to show the electric action of points (ElectricTourbillon) 20. — 1576. — Apparatus for showing the difference of both electricities — Wcinhold, Fig. 397 — 20. — or 27. 50 1577. — Apparatus for showing the attraction and repulsion of electric bodies — Weiuhold, Fig. 374 13. 25 1578. — Apparatus for proving the repulsion of homonymous electricities. — The 3 metal-rings, place themselves in a rigth angle to another, when being electrified 11. 1579. — do., for proving the electric density. — A hollow brass body on isolated stand , 10. EH No. 1586. 1580. — do, for proving, that electricity accumulates at the surface of bodies. — Frick, Fig. 612 — on stand 0. 75 or 11. — 1581. — do., Faraday's. — Frick, Fig. 609 8. 25 1582. — do, Frick, Fig. 610 10. - 1583. - do , Frick, Fig 613 13-25 1584. Isolated brass-ball on stand. — Miiller-Pouillet III. Fig. 126 10. — 1585. Distributing Conductor. — Frick, Fig. 614 6. 75 or U . — 1586. Riess's Distributing Apparatus 20. — or 27. 50 104 C. Gerliardt, Marquart's Lager chem. UtcDsilien, Bonn. Mk. Pf. Distributing Apparatus. 1587. — do., Bertram's, consistiug of a ball on isolated stand, with two hemispiieres, which may be taken off, isolated handles, a hollow zinc- screen on stand, 2 pendulum stands and 1 case with 12 balls of sun- flower-pith suspended on silk and linen-threads, with pincette . . . 33. - No. 1587. 1588. — do., with Riess's distributing apparatus No. 1586 53. 1589. — do., Faraday's, consisting of 2 hemispheres, one of which contains another isolated brass-ball. — On stand 33. 1590. Franklin's India-Rubber-Plate on isolated stand, prices varying according to size 6, 75, 11.— or 1591. — do., with swinging figure 20. — or 1592. — do,, dissectible, to show the theories of flasks 13. 25 or 1593. Frick's Apparatus for proving the repulsion of hymonymous electricities 1594. Discharger, simple without hinge 1.75 2. 75 or 1595. — do., with hinge 4. 50 or 1596. - do, with double handle and hinge 5. 50 or 16. 50 27. - 20. - 10. — 4. — 6. 75 9. — C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 105 Mk. Pf. Discharger. 1597. — do., Henley's, universal on mahogany board. — MuUer-Pouillet III. Fig. 153 18.— or 22. — 1598. Leyden Jars, cylindrical, closed high I nch 4, 5, 6, 7, 8, 10, 12 price 1. 75 2. — 3. — 4. 50 5. 50 6. 50 7. 75 1599. — do., cylindrical, open, with India Rubber cover high Inch 4, 5, 6, 7, 8, 10, 12 price 2, 50 4. 4. 50 5. — 6. 75 8. 25 9. No. 159S. 160). 1601. 1602. 1603. 1604. 1605. 1606. — combined to batteries, in box, with conducting wires — one battery of 4 jars, high Inch 4 II. 4 4 4 4 4 4 5 13. 25 6 17. 75 7 27. 50 8 33. - 10 42. - 12 50, — No. 1608. n. 1G09. Larger batteries may also ba obtained at prices proportionate to tlie number and size of jars, boxes and wire, 1607. Lightn ing Jars high Inch 4. 5. 6. 7. 8. 10. 12 price 2. 25 2.50 4.— 6.75 7.25 7.75 9.50 1608. Leyden Jar, dissectible, of bronce-varnished tin-plate, with glass handle high Inch 4. 5. 6. 7. 8. 10. 12 price 3.— 4.50 6.75 8.75 10.— 1609. — do., dissectible, of brass, India Rubber handle high In ch 4, 5, 6, 7, 8, price 3. 75 11. 10, 13.25 12 5. _ 7.75 10.50 11.50 13.25 16.50 106 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. Leyden Jar. 1610. — do., with chime of 2 bells 11. — or 16. 50 1611. — do., with automatical discharger 11. — or 16. 50 1612. Land's Measuring Jar, on an mahogany board, (he scale may be regulated with the hand 13. 25 1613. — do., with micrometric movement and divided scale ... 27. 50 or 40. — 1614. Lightening Tube long Inch 20, 40 according to diameter 2. 75 or 4. 50 4. 50 or 6. 75 1G15. India-Rubber Lightening-Plate with handle 5. — 1616. — do., on stand, prices varying to size from 6. 75 to 22. — 1617. Paper Tuft on isolated stand 5. — to 6. 75 1618. Glass Tuft with handle 1. 25 1619. — do., on stand 3. — No. 1612. No. 1622. No. 1634. 1620. Bullet-Rain, simple, with bullets 2. 75 1621. — do., on stand, with bullets 5, _ or 8. 25 1622. Flying wheel with 4 beams on stand 5. — 1623. — do., with 6 beams 6. 75 1624. Dancing Puppets, on stand 9. _ or 13. 25 1625 Electric Pistol 4. _ or 5. 50 1626. Lightening Tower or thunder-house 10. — or 13. 25 1627. Electric Pendulum, simple, on stand 4. — or 5. 50 1628. India-Rubber -Rod 2. 75 or 4. — 1629. Glass-Rod 1. or I. 75 1630. Mechanism for inflamming guo-powder 2. 75 or 4. 1631. — do, „ „ ether. — Frick, Fig. 600 5. — 1632. Electric Mortar — Frick, Fig. 639 8. 25 1633. Isolating Chair 6. — or 8. 25 1634. Carillon with 5, 5, 7 bells price G. 75 11. — 16. .50 1635. Glass Tube, the half of which is coated with sealing-wax 4. — 1636. Testing- Discs on isolated handle, each 1. — 1637. Isolating Plate 5. — or 10. — C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 107 Mk. Pf. 1638. Quadrant-Electrometer. — India Rubber Scale 5. 50 1639. — do., with etched glass-scale 8. 25 1640. Connecting Chain — .55 1641. Connecting Rods, supplied at the ends with hooks and bullets 1.75 to 5. — 1642. Lightening Plate for Rosetti's Figures, of India Rubber, with stand and with disc of 12 Inch diameter — Carl's Repert. 1873 — . 20. — or 27. 50 1643. Thomson's Quadrant-Electrometer. — Miiller-Pouillet III. Fig. 122 .. . 82. 50 1644. Apparatus for showing the magnetic effect of discharging. Miiller- Pouillet III. Fig. 199 5. 50 1645. Bullets of Sun-Flower-pith one dozen — . 55 1646. — do, coloured or giit one dozen — .85 or I. 10 No. 1647. No. 1658. 1647. 1648, 1649. 1650. 1651. 1652. 1653. 1654. 1655. 1656. 1657. 1658. 1659. 1660. Bennet's Electoscope, simple 3. 50 or 6. — — do., in form of a bullet, with stand and aluminium pendulum ... 13. 25 — do., with condensator 20. — — do., Beetz' Electroscope, with metal-casing and plate-glass-closing — Weinhold, Fig. 381 27. — Electric Condensator with metal-plates (to be taken off), India Rubber Disc and pendulum 27. 50 Mascard's Isolated Stand on Glass-Jar, partly filled with concentrated sulphuric acid 13. 2o Exciter for positive and negative electricity in form of a small disc- electrifying machine 20. — Dellmann's Electrometer. - Miiller-Podllet III. Fig. 119' . . . 33. — or 53. — — do., improved by Kohlrausch. — Miiller-Pouillet III. Fig. 120 . . . 220. — Carl's Tangent-Electrometer. — Carl's Repert. X. 69 66. — Apparatus for showing, that electricity exists only on the surface ... 11. — Kinnersley's Thermometer "2. — do. entirely of glass. — Weinhold, Fig. 420 6. 75 — do., Mascard's with fiae platinum-spirals — Carl's Repert. XI, pag. 338 22. — 108 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1661. Kohlrausch's Sliding Condensator 66. — or 110. — 1662. Conductor for surfaces with isolated liandle by means of wich the hemis- pheres may be taken off 27. — 1663. Resin Electrophore with simple zinc-cover and glass-handle diameter Inch 6, 8, 10, 13, 19 price 5. 50 7. 75 11. — 13. 25 20. — 1664. — do., with double zinc-cover and India-Rubber-handle diameter Inch 6, 8, 9, 13, 19 price 6. 25 9. — 13. 25 15. 50 25. No. 1662. No. 16G9.' 1665. — of thick India- Rubber, not of cut plates, but each plate pressed to avoid the shrinking of plates. With double cover and India-Rubber- handle diame ter Inch 6, 8, 9, 13, 19 price 7. 75 11. 50 16. 50 25. — 33. — 1668. Fox-tail 1. 50' 1667. — do , with handle 1. 75 1663. Electric Egg 20. — 1669. — do. large, with stop-cock and groand brass-stand 33. — 1670. Kienmayer's Amalgam, '/* pound 1. 75 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 109 Mk. Pf. 1671. I Copper and I Zinc-Plate, connected by copper-wire for the fandamental essay about galvanism 1. 50 1672. Volta's fundamental Essay, consisting of an electroscope with 4 con- densating plates varnished on 4 different sides 27. 50 1673. Quadrant-Electrometer. — Weinhold, Fig. 423 - 132. — 1674. Discharging Electrometsr. — Weinhold, Fig. 430 — 16. 50 1675. Fechner's Electrometer, in glass-box, with a zambonic column. — The electrodes may be regulated by micrometric-screw 53. — 1676. — do., without glass-box 40. — 1677. — do., with two zambonic columns, vertically standing . . 27. 50 or 40. — 1678. - do., Carl's 46. 50 1679. Condensing -Plates, consisting of a copper-and zinc-plate, with India- Rubber handles U. 50 1680. Buff's Apparatus for proving the electro-metoric power, which is produced when solid and liquid conductors are brought into contact. — MuUer- PouiUct III. Fig. 224 22. - no C. Gerbardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1681. Voltaic Pile. - Mullcr Podllet III. Fig. 228 with 10, 20, 30^ 40^ 5 pairs of plates Sh. 11.— 16.50 25.— 33.— 40.— 1682. Voltameter. — Muller-Pouillet III. Fig. 277 22. — 1683. — do., for separated gases — on stand 13. 50 1684. — do., for producing large quantities of hydrogen and oxygen. — Miiller-Pouillet III. Fig. 354 44. — 1685. — do., Bunsen's, only for hydrogen and oxygen gas 9. — 1686. — do., Hoffmann's. — Miiller-Pouillet III. Fig. 353 27. — 1687. — do., with glass-tube turning round its axle and adjusting pressure vessel — the gases may be led away combined or separately 40. — 1688. — do., with graduated tubes and separated pole-electrodes, for collecting the gazes mixed or separately 27. 50 or 44. — 1669. — do., for the objective demonstration of electrolytical decompositions and crystallisations. — Muller-Pouillet III. Fig. 364 — 13. 25 1690. Wiedemann's Apparatus for the Electrolysis of solutions of salts. — Miiller- Pouillet III. Fig. 368 50. — 1691. Apparatus for the electric endosmosis. — A glass-tube bent in form of an U with porous wall. - Miiller-Pomllet III. Fig. 370 — 2. 75 1692. Apparatus for decomposing salts, with platinum electrodes. — Frick, Fig. 728 2, 75 or 5. — 1693. Wiedemann's Apparatus for the exact measuring of the fluid conduced to the negative pole — With copper or platiuum-cylinder 27.— or 50. — 1694. Jacoby's Galvanoplastical Apparatus 5. — or 6. 75 1695. — do., consisting of a large vessel of glass or wood — (through-apparatus) 5.—, 8.25 or 13. 25 1696. Bertram's Apparatus for decomposing water 13. 25 1697. — do., with graduated tubes 20. — 1698. — do., smaller and simpler 6. 75 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Ill Mk. Pf. 1699. Horsford's Apparatus for determining the resistance of fluids — Miiller- Pouillct III. Fig 321 10. — 1700. — do,, Miiller-Pouillet HI. Fig. 3-22 • 22. — 1701. — do. Becquerel's. MuUer-Pouillet III. Fig. 320 11. 60 1702. — do., Miiller-Pouillet III. Fig. 823 11. 50 1703. Apparatus for examining volatile liquids. — Miiller-Pouillet III. Fig. 324 16. 50 1701. Apparatus for proving that heat is produced by the galvanic current. — MuUer-Pouillet III. Fig. 343 , 20. — 1705. Apparatus for proving that heat Is produced in metal wires. — MuUer- Pouillet III. Fig. 346 13. 25 1706. — do., on stand 16. 50 1707. Daniel's Apparatus for the electrolysis ef solutions of salts — Miiller- Pouillet III. Fig. 358 40. - 1708. Daniel's Elements, prices varying according to size 1. 75, 2. 75, 4. — or 6. 75 1709. — do., transportable, high 4'/2 Inch 3. — 1:9 No. 1704. 1710. 1711. 1712. 1713. 1714. 1715. 1716. 1717. 1718, 1719, 1720, 1721, 1722. 1723, Meydinger's Element, high 6 Inch — do., high 9 Inch — do., simplest construction, high 6 Inch — Pattern such as used in the German Empire Element of Siemens & Halske's, high d'/j Inch — do., Minetto's, high 6 Inch — do,, Wollaston's, high 8 Inch Hare's Spiral, active surface I-/3 n yard. — Two parallel plates of copper and zinc are wound in form of spirals and isolated from another — This spiral is supplied with a handle and placed in a vessel, which is filled with thin sulhpuric acid (I: 10 or 12 volumioa) Smee's Element, consisting of a vessel and a silver-plated a plate placed between two zinc-plates, price varying according to size 5.50 11 — 16,50 or Grove's Platinum-Element size of platinum plate 6X3 Inch do., „ „ 4 X 2'/, „ do., „ „ IX I'/j „ Bunsen's Elements, with hollow coal-cylinders 4 — , 4. 50, 5. 25, 6. 50 or — do,, with massive cylinders . . . . 3. -, 3.75, 4.25, 5.—, 6.25 or 3. — 5. — 2. 25 2. 50 3. — 3. — 7. 75 60. 25. 25. 15. 10. — 7. 75 7. 50 50 112 C, Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1724. Chromic-Accid-flask-element with 3 coal and 2 zinc-plates 20. — 1725. — do., with 3 coals and 1 zinc-plate' 16. 50 1726. — do., smaller 13. 25 1727. — do., smaller, with 1 coal- and 1 zinc-plate 8. 25 1728. Dipping battery ot my own construction, without rack and pinion and without dented rods, by which frequently the frame is shaked, with 2 elements 30. — 1729. — do., with 4 elements ■ 46. — 1730. — do , „ 6 „ 64. — 1731. - do., „ 8 , 80. — 1732. — do., „ 10 „ 94. — 1733. - do., „ 12 „ 107. 50 118 No. 1733. No. 1727.. 1734. Leclanche-Elements, according to size 3. — , 3. 50, 5. — , or 6. 75 1735. Manganese-Element, high 10 Inches 5. 50 1736. Chloride of Silver Element. 3'/e Inches high 10. -- 1737. Plante's secondary element, 6 Inches high 15. 50 1738. — do., high 10 high 33. — Clamps for Elements. 1739. — for 2 wires, square or round — .50 1740. — for wire and plate —.70 1741. — for 2 wires —.70 1742. — for coal-plates 1.75 or 2. — 1743. — with wood-screws • — .70 1744. — with metal-screws from — . 70 to 1. 75 1745. Metal-Galvanoskope of metal in form of a box 11. — or 16. 50 1746. — do., of wood 11. — 1747. — do., with adjusting screws and stopper 22. — 1748. — do., with copper-band, on polished wood-board Miilicr-Pouillet III. Pig. 390 10. - C. Gorbardt, Marquart's Lager chemischer Utensilien, Bonn. 113 Mk. Pf. 1749. Slohrer's Vertioal-Galvanoscope. — Miiller-Pouillet III. Fig. 391 22. — 1750. — do., Stohrer's - Miiller-Pouillet III. Fig. 398 40. — or 66. — 1751. r. 'K No. 1750. No. 1781. do., simple with a strong spiral and long index, for demonstration 13. 25 or 25. 1752. Bertram's Galvanometer, with divided opal-glass-scale 66. - 1753. — do., with brass-scale, silvered or nickelled, with micrometric screw, the frame throughout of metal 137. 50 114 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. Bertrams Galvanometer 1754. — as 1752, but smaller, with scale on satinized paper 30. — 1755. — as above, but with scale on opal-glass 33. — 1756. Schweigger's Multiplicator with simple needle 27. — 1757. — do., with a pair of astatic needles 40. — 1758. — do, Nobili's with a pair of astatic needles, MuUer-Pouillet III. Fig. 395. 53. — or 72. — 1;B No. 1754 u. 1755 No. 1760. 1759. — do., Wiedemann's. Miilier-Pouillet III. Fig. 408 ... . 82. 60 or 132. 17C0. Weber's Mirror-Galvanomefer. — Miiller Pouillet III. Fig. 406 165. 1761. Toepler's Reflecting Galvanomelep. Weinhold, Fig. 438 & 439 .... . 143. i:i2 "^iTs " No- 1'62. No. 1768. 1762. Weber's Tangent-Box-Compass, with simple copper-ring, and needle on a point, diameter 11 Inch. Simple. Miilier-Pouillet III. Fig. 284 . . 30. — 1763. — diameter 13 Inches, best make 66. — l'?64. — do., needles suspended on threads of cocoon 82. 50 1765. — with several wire-windings, needle suspended on threads of cocoon 66. — or 94. — 1766. — do., Gaugain's. — Muller-Pouillet III. Fig. 402 100. — or 155. — 1767. Sine-Box-Compass. — Miilier-Pouillet III. Fig. 403 133. — 1768. — do., Siemens & Halske's. — Miiller Pouillet III. Fig. 404 165. — or 230. — G. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 115 Mk. Pf. 1769. Oersted's Fundamental Essay for showing how the galvanic current acts upon the compass-needle. — MiiUcr-Pouillet III. Fig. 387 . . 13. 25 or 16. 50 1770. Amperes Frame with 3 figures and Soleuoide. Muller-Pouillet III. Fig. 479 27. — or 40. — 1771. — do., new constructioD, with 4 figures, solenoide and commutator. — Miiller-Pouillet III. Fig. 484 55. — No. 1771. 1772. — do., as 1771, but with conductors of aluminium 82. 50 1773. De la Rive's Apparatus for demonstrating how magnets are acting upon -^ moveable currents. — Miiller-Pouillet III. Fig. 483 — 5. 50 1774. — do., with solenoide 10. — 1775. Buff's Apparatus for showing the attraction of parallel currents of same direction and the repulsion of parallel currents which have opposite direction. - Miiller-Pouillet III. Fig. 490.- 40. - 1776. Roget's Spiral. - Muller-Pouillet III. Fig. 492 13. 25 1777 Garthe's Apparatus for showing how crossed currents are acting upon another. - Miiller-Pouillet IH. Fig. 496 16. 50 or 27. - 116 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Garthe's Apparatus for showing how crossed currents are acting upon another. 1778. — do., de la Rive's. - Muller-Pouillet III. Fig. 499 9. — or 13. 25 1779. Apparatus for making a moveable magnet turn round a firm current. — Muller-Pouillet III. Fig. 520 22. - 1780. Apparatus for making a magnet turn round its own axle. — Miiller-Pouillet III. Fig. 521 22. — 1781. - do., Miiller-Pouillet III. Fig. 522 20. - i:6 No. 1783. 1782. Apparatus for making a conductor turn round a fixed magnet 22. 1783. The apparatus 1779, 1780 & 1782 combined on one stand 53. 1784. Gore's rotating bullet 15. 50 or 20. 1785. Barlow's rotating Wheel. — Miiller-Pouillet III. Fig. 517 . . 16. 50 or 22. .LB; No. 1788. 178G. Apparatus for making one current turn under influence of an other. — Muller-Pouillet 111. Fig. 525 — 16. 50 1787. Apparatusforshowing the inclination of moveable currents. — Frick, Fig.' 819 20. — 1788. Wheatstone's Rheostate, consisting of a roller of serpentine or alabaster, with strong wire, Muller-Pouillet Fig. 301 50. — 1789. — do., with a double roller and fine wire — Muller-Pouillet IIF. Fig. 303 60. — 1790. Poggendorf's Rheocord. — Miiller-Pouillet III. Fig. 304 53. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 117 Mk. Pf. 1791. Eisenlohr's Resistance-Column, with roller of serpentine-stope. — MuUer- Pouillet III. Fig. 305 22. — or 40: — 1792. Siemen'8 Stopper-Rheostate. — Miiller-Pouillet III. Fig. 306 50. — 1793. Siemen's Etalon of the Unify of resistance - Miiller-Pouillet III. Fig. 307 18. — 1794. Wheafsfone's Bridge. — Miiller-Pouillet III. Fig. 317 22. — 1795. — do, same modified by Siemens, — Miiller-Pouillet III. Fig. 319 . . 50. — 1796. Sfohrer's Pacfiytrope. — Miiller-Pouillet III. Fig. 267 22. — 1797. Ruhmkorrs Gyrotrope. - MuUer-Pouillet III. Fig. 272 U. 50 1798. Ruhmkorff's Commutator. — Miiller-Pouillet III. Fig. 273, according to size 11. 20 or 27. 50 1799. — do., same, in other form, open for schools 16 50 1800. — do., Du Bois-Reymond's 16. 50 1801. — do., Hermann's. - Weinhold, Fig. 436 11. — or 16. 50 1802. — do., MuUer-Pouillet III. Fig. 274 13. 25 or 20. - 1803. — do., Pohl's. - Miiller-Pouillet III. Fig. 275 16. 50 1804. - do., Renschs. - Frick, Fig. 799 16. 50 1805. — do., as used for Ampere's frame — Miiller-Pouillet III. Fig. 43t . . 20. — 1S06. Seebeck's Thermoelectric Element, consisting of a rod of bismuth with copper-band and load-stone, on stand. — Muller-Pouillet III. Fig. 527 — 13. 25 or 16. 50 1807. — do., same but with a rod of antimony 10. — or 13. 25 1808 Thermoelectric rectangle, consisting of bismuth and antimony. — Miiller- Pouillet III. Fig. 528 15. 50 or 20. - 1809. Thermoelectric element, consisting of a rod of bismuth and a copper-wire- band - Miiller.Pouillet III. Fig. 529 8. 25 1810. - do., open, consisting of a bismuth, rod and 2 soldered strips of copper — Miiller-Pouillet HI. Fig. 530 10- — 1811. — do,, Miiller-Pouillet III. Fig. 531 20. — 1812. - do., for determining the temperature of different bodies - MuUer- Pouillet III. Fig. 533 20. - 1813 - do, consisting of antimony and bismuth, with 2 fastening screws . . 10. - 118 C. Gerbardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1814. Becquerel's Thermoelectric Knot, of platioum wire — Miiller-Pomllet III. ■ Fig 539, varying according to weight from 6. — to 13. 50 1815. — do., Nobili's, of easily oxydating metals, as: zinc, iron &cet. — from 1. — to 3. — 1816. Peltier's Thermoelectric Cross. — MiiUer-Pouillet III. Fig. 540 16. 50 or 22. — 1817. Peltier's Apparatus for producing heat or cold by the electric current — Frick, Fig. 716 - 16. 50 or 22. — 1818. — do., Weinhold, Fig. 48S 40. — 1819. — do., Magnus's. — MuUer-Pouillet III. Fig. 541 27. 50 1820. — do., Magnus's. — MuUer-Pouillet HI. Fig. 542 . 5. — No. 1817. 1821. Nobili's Thermoelectric Column, on stand, turning to all directions and to be risen or lowered. — Miiller-Pouillet III. Fig. 543. — With 15 elements 1822. 1823. 1824. 1825. 1826. 1827. 1828. 1829. 1830. 1831. 1832. 1833. 1834. 1835. — do., with 20 elements. - do., „ 25 „ - do., „ 30 „ - do., „ 40 „ — do., „ 50 „ Conical Receiver of brass, for the precedent thermo piles — do., of german silver Cylindrical Receiver of brass do., of german silver Franz's Thermoelectric Pile. — Miiller-Poaillet II. 2 Fig. 388 1.16.- — . do , Markus's. Miiller-Pouillet III. Fig. 245 with 16 elements . — do., with 20 elements - do., „ 40 „ — do. „ 60 27. 50 40. — 4G. 50 55. — 72. — 82. 50 5. 25 6. 75 2. 50 3. 75 63. — 50. — 72. — 137. 50 200. - C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. 119 Mk. Pf. Franz's Thermoelectric Pile. 183S. — do., Noe's. Muller-Pouillet III. Fig. 54S . . . . 33. — 44. — or 66. — 1837. — do., Clamond's fitted for coal-gas, witli regulating gauge; especially recom- mended for chemical and galvanoplastical labours — with CO elements 110. — 1838. — do , with 120 elements 190. — 1839. — do, ,,150 „ 215. — 1840. — do., ,,270 „ 3C5. — No. 1837 bis 1840. 1841. Electro-Magnet, bearing about 30 £, without stand 13. 25 1842. — do., with stand 20. — 1843. — do., bearing about 80 f, on strong wood-board, to turn the poles above, and to show the magnetic figures by means of filings with scale 40. — or 53. — hE= IL llMPjl^ k- — =^- — — — — — — — v-s No. 1850. 1844. — do, smaller, without stand from 3. 50 to U. 1845. — do., larger, with lever and scale, t'ricli, Fig. 782. .. . 83. — or 132. Electro-Maflnets for the diamagnetic essays — see No. 1930 to 1932 — 184G. Joule's Electro-Magnet, in form of cylinders, bearing 50 £ 20. 1847. — do., bearing 100 £ ^°- 1848. — do,, bearing 200 £ ^^■ 1849. Magnetizing Spiral 11. — or 22 1850. Ritchie's Electromagnetic top. - MuUer-PouiUct III. Fig. 448 22. - or 33. 120 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk Pf. Ritchie's Electromagnetic top 1851. — Ritchie's small, with mercury-iDterruptor 10. — 1852. Gruel's Electro-Magnetic Swinging-wlieel 11. — 1853. — do., large 50. — or 66. — 1854. Electromotor or turning Geissler's tabes, coloured discs etc. 33. — or 44. 1855. Electric Railway of simplest kind, element excl 25. 1856. — do, with a bottle-element 38. No. 185.5. No. 1S59. 1857. Wagner's Electromagnetic Hammer. — Miiller - Pouillet III. Fig. 564 16. 50 or 27. 50 1858. — do., connected with a clock and receiver, to be nsed also as acoustic apparatus for the air-pump 27. 50 1859. — do., same without receiver 22. — C. Gerhardt, Marquarl's Lager cheraischer Utensilien, Bonn. 121 Mk. Pf. 1860. Schumann's Electromagnetical Inclinatory, for the following experiments: 1. attraction of iron by a magnet. 2. Poles of the same name repel and those of different names attract each other. 3. the phenomenon of the inclination. 4. the magnetic excitement of soft iron throngh the terrestrial globe. With full instruction for use 33. — 1861. Electromagnetical rotating apparatus. — Frick, Fig. 788 . . . 10, — or 16. 60 1862. Page's Electromotor, with two vertical spirals, in form of a steam-engine. — Miiller-Pouillet III. Fig. 458 & 459 165. — or 220. — 1863. — do., as water-pump 22. — or 30. — 1864. — do., as stroboscopic cylinder 22. — or 30. — 1865. Telephone with 27 yards conducting wire, each pair 13. 50 or 16. 50 No. 18G0, No. 1866. 1866. 1867. 1868. 1869. 1870. 1871. 1872. 1873. 1874. 1875. 1876. 1877. Interrupting wheel. — MuUer-Pouillet III. Fig. 563 11. — or 16. 50 Spiral-Band for magnetizing steel-rods. — Miiller-Pouillet III. Fig. 434 10. — , 13. 50 or 16. 50 Oberbeck's Iron Ring with magnetizing and inducing spiral. — Miiller- Pouillet III. Fig. 437 7. - Waltenhofen's Apparatus for showing the action of a spiral on magnets and soft iron, Muiler-Pouillet III. Fig. 439 20. — Wertheim's Apparatus for producing galvanic tunes. — MuUer-Pouillet III. Fig. 445 — 40. — Stbhrer's Electromagnetic Motor. — Miiller-Pouillet III. Fig. 455 ... . 1G5. — Index-Telegraph, small pattern with key 27. 50 — same as precedent, but with 2 stations 53. — — larger pattern with key 60. — Morse-Telegraph, small with clock-work and key, one station 53. — — do., two stations 100. — — do., without clock-work, with winch and weights 35..— 122 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. Morse-Telegraph 187S. — do., constructed in my own works, new pattern exceedingly adapted for ttie instruction, 2 stations, complete with clock-worck aod elements 110. — 1879. — do., without clock-work, with winch, 2 stations 82. 50 No. 1878. u. 1379. 1880. — do., large, under glass-box. — With galvanoscope, feeler, relais &c. — Muller-Pouillet III. Fig. 462 150. — 1881. Plettner's Relais 53. — 1882. Electric Clock, for schools. Demonstration Apparatus .... 50. — or 82. 50 1883. Inductions-Cylinders, one of which moveable, with steel-magnet, interrupter and handles. — Miiller-Pouillot III. Fig. 562 and 575 — 40. — 1884. Du Bouis-Reymond's Sliding Apparatus, for physiological purposes. — Muller- Pouillet III. Fig. 566. — 20. - or 27. 50 1885. RIess's Inductions-Spiral, horizontal. — Muller-Pouillet III. Fig. 657. — 27. 50 18S6. — do, vertical, with sledge and scale divided into millimeters 40. — C. Gerhardt, Marquart's Lager chem. Utensilieu, Bonn. 123 1887. Buff's Disjunctor. — Muller-Pouillet III Fig. 679 1888. Induction-Apparatus, small, on board 1889. — do., larger, on mahogany-box 13. 25 or 1890. — do., du Bois-Rey mend's. 40. — or 1891. — do., Bo.yerlacber's 1892. - do., Gaiffe's ■ 1893. — do., Spamer's Mk. Pf. 27. 50 8. 25 27. 50 50. — 39. — 27. 50 60. — No. 188«. 1894. Magneto -Electric Rotating -Apparatus with lying magnets and handles, in box ' 27. 50 or 40. — 1895. — do., with 2 magnets 50. — 1896. Stohrer's Magneto-Electric Induction-Machine - Muller-Pouillet III. Fig. 612 200. — 1897. Fundamental Essay about Induction: two wire-spirals, one with fine, the other with strong wire — Weinhold, Fig. 472 27. 50 1898. Weber's Induction-lnclinatory. - Muller-Pouillet III. Fig. G67 . 82.50 or 110. — 1899. Arrago's Apparatus for showing the action produced on the compass-needle. — To be placed on the centrifugal - machine — Muller-Pouillet III. Fig. 662 22. — 1900. Apparatus for showing the induction produced on electric currents by terrestrial magnetism — Muller-Pouillet III. Fig. 666 .. . 94. — or 120. - 1901. Puckler & Fessel's Apparatus, for proving tlie reaction of currents induced by movement — Muller-Pouillet III. Fig. 663 60. — 124 C. Gerhardt, Marquart's Lager chemischer Utensilien, Boun. Mk. Pf. Plucker & Fessel's Apparatus, for proving the reaction of currents induced by movement 1902. — do., Faraday's. — MiillerPouillet III. Fig. 658 45. — 1903. Microplione, — Muller-Pouillet III. Fig. 653-655 5. — or 6. 75 1904. De la Rieve's Apparatus for sliowing liow the magnet acts upcn electric discharging in thin gases. — Miiller-Pouillet III. Fig. 603 — . . . . 50. — 1905. — do., more simple, without electro -magnet — Miiller-Pouillet III. Fig. 604 — 20. — 1906. Ruhmkorff's Spark-Inductor, with 800 windings 10. — 1907. „ „ 1000 , 13. 25 1908. „ „ 2000 „ 18. — 1909. „ „ 3000 „ 25. — 1910. „ „ with platinum-interruptor and pole-screws which may be taken off, lengh of the coil '/s ^^<^^ ^5. — 1911. — do., same but with current-changer 54. — No. 1902. No. 1911. 1912. — do., as 1911, length of coil Vs Inch 105. — 1913. - do., „ „ iVs „ 175. - 1914. - do., „ „ 3 „ 265. — 1916. - do., „ „ 6 „ 420. — 1916. - do., „ „ 10 „ 600. - 1917. Geissler's Tube with uranium-glass in different colours, 4 Inch long ... 1. 75 1918. — do., 6 Inch long . . . • 2. 75 1919. — do., 8 Inch „ 3. 75 1920. — do., fluorescing, 6 Inches long 4. 25 1921. - do., „ 8 „ „ 5. - Larger Tubes on demand at moderate prieces. 1922. Spectral tube, filled with gases or vapours 5. — or 10. — 1923. MItscherlich's" Eight Spectral Tubes 18. — 1924. Phosphorescing Tube 5. 25 or 6. 75 1925. Fluorescing tubes showing different fluorescences in different form and execution from 5. — to 60. — 1926. — do,, lighting at night from 11. — to 40. — 1927. Houzeau's Ozon-Tubes each 20. — 1928. Spectrum of 7 phophorescing tubes in form of a Stereoscope 15. 50 1929. Fluoroscope 10. — C. Gerbardt, Marquart's Lager cliemischer Uteusilien, Bonn. 125 Mk. Pf. 1930. Large Electro-Magnet for diamagnetical essays. — Height of the iron- nucleus about 16 Inches, thickness 2-2'/, Inch. With 6 graduated spirals to be connected with eachother. With commutator & 2 perforated half- anchors, the cylindrical iron-sets of which have a different form at each end; on these half-anchors are placed two angles on which several objects may be attached; glass-box with mechanism for rising and lowering the cocoon-thread 550 — 1931. — do., same but with only 2 spirals 470. 1932. — do,, height of the iron-nucleus lO'/j Inch, thickness 20 Inch. — With only 2 spirals, without glass-box, with simple stand 320. — 1933. 1934. 1935. 1936. 1937. 1938. 1939. 1940. Secondary Apparatus for diamagnetic essays. Small massive copper-disc 2. — ' „ „ bismuth-disc 3. 75 „ „ bismuth-bullet 3. 50 Faraday-Glass with stand to place the glass upon 22. — Large Stand with copper- disc of 13 Inch diameter, with axle and winch, for showing, that it is not possible to turn the copper- disc, when it is placed between both poles 27. — Rotating-Mechanism with tube, for melting easily fusible metals between both poles 20. — Tube, which can be put In both half-anchors — With 2 Nicol's prisms, divided disc and index 55. — Rods of different metals from 1. — to 2. 50 126 C. Gerhardt, Marquart's Lager chem. Utensilien, Bonn. Mk. Pf. 1941. Tyndalls' Apparatus for showing, that a magnetic polarity is produced in a diamagnetic body under influence of a magnetizing power and that this polarity is opposite to that, which an Iron rod would assume under similar circumstances. — Miiiler-Pouillet III. Fig. 684 305. — 1942. Ruhmkorff's Apparatus for proving that the polarizing plane is turned by magnetizing powers, — Miiller-Pomllet III. Fig. 693 600. — 1943. — do., Bottcher's. — Muller-Pouillet III. Fig. 695 105. — 1944. Siemens' Dynamo-Electric Hand-Machine A. Constructed for hand-movement in my works. Cylinder-Inductor (Double T Anchor) System. — This system is acknowledged by authorities as being the best for schools, for acquainting pupils with dyuamo-elcctiic principle and its application. The required expense of power is a very small one. — The current (20 Bunsen-Elemente) is fully sufficient for all essays which may bo made in schools. — The machine can be put into action by any boy. — Full particulars on application. Complete, with strong wooden table, swinging-weels Ac. but without the supplcmenfary apparatus. — With special instruction for use. . 420. C. Gerbardt, Marquart's Lager chem. Utensilien, Bonn. 127 Mk. Pf. Siemens' Dynamo- Electric -Hand- Machine 1945 — B. same machine, smaller, mounted on a oak-wood-block. — Force of current = 4 Bunsen Elements. — Special instruction on demand 165. — 1946. — C. same, for physiological effects 105. The excellent action of my dynamo-electric Machine is fully warranted; for testimonials received see the first side of this Catalogue. Any other constructions of dynamo-electric Machines will also be supplied on demand-although for school-purposes only Siemens' Cylinder-Inductor- (Double T. anchor) System can be recommended. 128 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Supplementary Apparatus for the dynamoelectric Machines A. & B. 1947. Wood-Model of the double T. anchor, for the machine A 2. 75 1948. — do., same for macliiae B 1. 75 1949. Vacuum-Incandescent-Lamp on wood-stand, with fastening screws .... 11.— 1950. — more elegant, on large stand IG. 50 1951. 1952. on brass-stand, moveable in bullet-hinges, with parabolic-mirror (to be taken off) and bullet-clock of opal-glass 50. — do., Bernstein's, with a hollow-coal- band 16. 50 No. 1957. 1953. Candelaber with 2 incandescent lamps and commutator, to make the lamps buro single or together 27. 60 1954. — with 3 incandescent lamps and commutator 40. — 1955. — „ 4 „ „ „ 50. — 1956. Hand-Regulator for bow-light 13. 50 1957. Automatical Regulator for bow-light, on which the top coal is moveable, the bottom one fixed 55. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 129 Mk. Pf. Automatical Regulator for Bow -Light. 1958. — do., regulating both carbons in such manner, that the light remains of equal intensity 100. — 1959. Carbons for No. 1957 and 1958 a pair 1. 10 1960. Magic Lantern, fitted with a bow-light lamp No. 1958 210. — (Other Lanterns see No. 1226, 1227, 1228). Any Sciopticons will be fitted with bow- or incandescent light at cheapest prices. 1963. 1964. 1965. 1966. 1:6 No. 19G2. 1 -M No. 1966 u. 1967. 1961. Stand for fixing thin wires for glowing- or melting essays, simple, on wood-stand ...-...,/' 5. 50 1962. — do., more elegant, on brass-stand 10. — 1 No. 1966 u. 1967. Platinum-Spiral for Machine A — do., „ „ B Iron-Wire e^'='» '=y"°"^«'^ "• Apparatus for decomposing water No. 1682-1639, and 1696-1698. Coil-Inductors see No. 1906-1916. Electro -Magnets see No. 1841-1848, 1930-1932. Electro-Magnetic-Motors, see No. 1850—1864. Apparatus for transversal swingings see No. 809 and 810. Electric Railway with rails. The machine of this electric railway is of the same construction as my dynamo-electric machines. By loosening 9 50 40 45 130 C. Gerbardt, Marquart's Lager cbemischer Utensilien, Bonn. Mk. Pf. of three screws it may be taken from the waggon and fastened at a stand (this will be added to each apparatus). It may then serve as motor for turning Geissler's Tubes, Coloured discs &-cet S2. 50 Electric Railway. 1967. — do., same as 1965, but without the mentioned stand 80. — 1968. Mechanism for placing Geissler's Tubes &-cet. on the stand 8. 25 1969. Electric Railway, same as 1966, but smaller and fixed on the waggon . 33. — 1970. Apparatus for registering the number of rotations 7. — 1971. — do., automatical, registering up 1000 15. — 1972. Jablochkoff's Candles 1. 75 Other apparatus which can be used with the dynamo -electric hand-machine are mentioned at the respective chapters. yill. Meteorology. 1973. Pouillet's Pyrheliometer. — Miiller-Pouillct II. 2 Fig. 301 82. 50 1974. Standard Thermometer, divided into '/n " degrees, 0— 102 ♦, patented from 50. — to 66. — 1975. — do., each degree divided into '/s ° — from 30 up to 50. — patented from 16. 50 to 33. — 1976. — do., in brass frame, mounted for being attached to the window, scale divided into '4° 27. — 1977. Maximum and Minimum -Thermometer with milk-glass-scalc and brass-arm 27. — 1978. Minimum -Thermometer, Negretti' & Zambra's Pattern, Vs °> with patented fastening mechanism from 1.3. 50 to 16. 50 1979. IMinimum-Thermometer, the tube filled with amyl-alcohol, each degree divided into '/j" from 10. — to 16. 50 1980. Maximum- and Minimum-Thermometer, small, for travellers, with box . . 22 . — 1981. Pocket-Thermometer in brass-box from 4. 50 to 6. 75 1982. Thermometer for measuring the temperature of earth, for great depths, each degree divided into tenths 13, 25 1983. — do., same for less profound depths, each degree divided into fifths . 11. — 1984. — do., for the surface of earth, each degree divided into fifths .... 11. — 1985. Laments Box, for 4 earth-thermometers 40, — 1986. Thermometer- Case, which may be approached to the window of the observing room and automatically opens 72. 50 1987. — do., more simple 60. — 198S. Thermometer for wells 8, 50 1 989. Hypsomeler, with boiling vessel, steam-casing, and thermometer, each degree divided into '/,„", with box 55. — to 75. — C. Gerhard t, Marquart's Lager chemischer Uteusiliea, Bonn. 131 Mk. Pf. Hypsometer. 1990. — do., large, with a thermometer divided into V5/ 132. — 1991. Apparatus for testing and comparing thermometers, with rotating stirrer and mechanism for maintaining a constant temperature from . 55. — to 132. — m |lil9f'i: llil!'''': Iff ri'' If " iiiii ;( in i ail 'i. !'■ .'''.' '1 Wm •If m No. 19S5. 1992. Standard -Barometer, (Vessel-Siphon-Barometer), System Wild-Fucss. — Adjusting is made by microscopes. The coincidence of axles of the microscopes and of the zeros of the nonius may be determined at the instrument. The nonius shows 0,05 and can be supplied at special demand also on 0,02 Mm., with a tube of Vs Inch diameter 360. 9* 132 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. Standard -Barometer. 1993. — do., like 1991, but without microscopes. System Wild-Fiiess. — Ad- justing is made by a visor, the nonius may be read up to 0,05 Mm. Report on the scientific Instruments on the Berlin Industrial- Exhibition 1880, page 222 295. — 1994. - do., System Wild-Fuess. — With a tube of 8 Mm. diameter, without adjusting screw at the nonius, the nonius shows 0,10 Mm 210. — 1995. Siphon-Barometer with glass-stop-cock, for chemical laboratories, divided glass-tube. With glass-nonius indicating 0,10 Mm. . _ 165. — No. 2005. 1996. — a wide glass-tube with scale divided into millimeters on a board . . 66. 1997. Fortin's Travellers Barometer for measuring heights. The nonius indicates up to 0,10 millimeter. With stand in case 265. 1998. — do., more simple, without stand and without box 140. 1999. Vessel -Barometer with reduced scale. The nonius indicates up to 0,10 millimeter — this instrument is employed by the stations of the German Maritimal Observatory 165. 2000. — do., same as 1998, but simpler 127. No. 2008. 2001. Barometer for Ships, introduced by the English, German and Russian Marine 145_ 2002. Metal-Barometer (Aneroid-Barometer) different patterns from 27. — to 66. 2003. Regnaulfs Hygrometer, with simple aspirator 110. — or 155. 2004. — do., with double aspirator . 100. — or 140. 2C05. — do., Daniel's with stand 14. — 20. or 40. 2006. — do., Saussure's Hair- Hygrometer, simple, on japaaned wood with thermometer 13. 2007. — do., entirely of metal, with thermometer and box 40. 2008. - do., Ernecke's New Hair- Hygrometer in brass frame 33. 60 C. Gerhardt, Marquart's Lager cliemischer Utensilien, Bonn. 133 Regnault's Hygrometer. 2009. — do., same with thermometer, in oak-wood-frame ■ 2010. — do., with thermometer and aneroid-barometer, in oak-wood-frame . Mk. Pf. 44. - 66, - No. 20O9. No. 2010. No. 2011. 2011. — do , in varnished metal-easing . . . . 2012. do., with thermometer upon the scale 22. - 27. 50 134 C. Gerhardl, Marquart's Lager chemisclier Utensilien, Bouu. Mk. Pf. 2013. 2014. Regnault's Hygrometer. — do., with ringing arrangement, the electric current is closed by the index of the instrument at two different degrees of humidity, which may be at liking determined. — Most practical for hot-air-heating- systems, spin-houses, breweries. — Id japanned metal-casing, without ringing arrangement and elements — do., same as 2012, but in brass-frame on polished wood-board . . . 33. — 44. — No. 2013 n. 2014. 2015. Brass-Arm by means of which the hygrometers No. 2008 and 2011 may be fastened out of the window G. 75 2016. Eaves for placing upon the hygrometers No. 2008 and 2011 4. 50 ^ w-T^r lnJjmosc(ir*i5 |p4liJ ♦ I' |r^/- •«° III W'-'"""^ Arm and Eaves or No. 2015 and 2016. No. 2017. i;3 No. 2019. 2017. August's Hygroscope. — With vegetable fibre, metal casing, opal-glass scale 16. — 2018. — do., same, with thermometer 20. 2019. — do., in japanned metal-casing 8. 25 2020. — do., same with a thermometer 11. — 2021. August's Psychrometer, on metal-stand, with opal-glass-scale divided into tenths of degrees 55. — 2022. — do., same, each degree divided into fifths of degrees 48. — 2023. — do., on opal-glass-scale, each degree divided into tenths, but on a simple wood-stand 35. — C. Gerhardt, Mai-quart's Lager chemisclier Utensilien, Bonn. 135 Mk. Pf. August's Psychrometer. 2024. — do., each degree divided into fifths 31. — 2025. — do., on paper scale, each degree divided into tenths 30. — 2026. — do., on paper scale, each degree divided into fifths 2.5. — 2027. Pschyrometer, for travellers, with dissectible brass-stand and box ... 66 — 2028. Riidorfs Apparatus for determining the quantity of vapour contained in the atmosphere. — Report of the German chemical Society, XIII"'. year; No. 2, 1880 50. — 2029. Rain-Measurer, simplest kind, of japanned tin-plate 22. — 2030. ~ do., Ernecke's with automatical registering 82. 50 No. 2036. 2031. Anemometer, with Robinson's dish-cross, dissectible, numbering up to 10,000 rotations, in bos ^0^- — 2032. — do., Casella's. — With stopping -arrangement and numbering-work to be used up to 10,000,000 meters, with leather box 94. — 2033. Wlld'8 Wind-flag ^*- ~ 2034. August's Apparatus for measuring the height of the sun and for dotcrmimng the exact time of day 40. — 2035. August's Sun Dial (Sklostate) 40. — 2036. — do., same, in most perfect execution . . . ' • • 200. — 2037. — do., same with heliostate 2^5. — 2038. August's Fenestrole 16. 50 2039. August's Apparatus for indicating mid-day 8. 2y 136 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Set I for Superior Schools recommended of C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 2040. 1 Parallelogram as No. 7 . 8. 50 2041. 1 inclined plane as No. 19 16. 50 2042. 1 Mechanism for explaining the screw as No. 26 . . . 2. 25 2043. 1 Stand with one moveable and one fixed pulley ... 11. 50 2044. 1 Lever-Apparatus. — Frick as No. 65 8. 25 2045. Equilibrium figures No. 76 5. 50 2046. 1 Chinese Stair • chimber No. 82 3. 25 2047. lOBolognianflasksasNo. 109 1. 75 2048. 25 Batavian Glass -Tears as No. 110 1. 25 2049. 1 pair of adhesive Glass- Plattes as No. 121 ... . 6. 50 2050. 1 Bertram's Centrifugal - Machine as No. 146 . . . 24. 50 2051. 1 Centrifugal -Pendulum as No. 149 5. 50 2052. 1 Glass- Ballon as No. 169 4. — 2053. 1 Apparatus showing the difference of the diameter of earth — as No. 185 .. . 6. 50 2054. 1 Apparatus - laws of the Pendulum — as No. 210 . 6. 50 2055. 1 Apparatus — Illustration of buoyancy — as No. 276 '2. 75 2056. 1 Cartesian swimmer as No 287 1. 75 2057. 1 Weight Areometer as No. 293 5. 50 2058. Communicating Vessels as No. 313 1. 75 2059. 1 Segner's Watter- Wheel as No. 362 6. 50 2060. 1 Suction-pipe as No. 403 — . 90 2061. 1 Heronsball as No. 429 . 1. 75 2062. 1 Model of a Sucking-Pump as No. 441 2. 50 to be Carried forward: 135. 65 2063. 2064. 2065. 2066. 2067. 2068. 2069. 2070. 2071. 2072. 2073. 2074. 2075. 2076. 2077. 2078." 2079. 2080. £081. 2082. 2083. 2084. 2085. 2C86. 2087. 2C88. 2089. Mk. Pf. Brought forward: 135. 65 1 Model of a fire-engine as No. 448 4. 50 1 Air Pump as No. 474 . 22, — 1 Receiving -Vessel for air- Pump as No. 495 ... . 2. 25 1 testing barometer with scale as No. 501 3. 30 1 India- Rubber- ball with cock as No. 523 2. 75 1 simple labium as No. 759 5. — 1 tuning-fork a ore as No. 830 2.25 2 Angular mirror as No. 917 3. 25 1 Caleidoscope, as No. 919 3. 25 lSpherical-mirrorasNo.941 4. — 1 Prism No. 957 1. 25 1 Microscope No. 1169 . . 10. — 1 dz. Microscopic Objects . 3. — 1 Apparatus action of steam No. 1331 4. — 1 Compression- tinder- bos, as No. 1448 5. — 1 Apparatus- Conduction of heat — as No. 1458 .. . 6. 75 1 Load -Stone as No. 1519 1. 25 lHorse-Shoe-loadasNo.1524 1. 75 ICompassNeedleasNo. 1526 1.50 1 Stand for the needle as No. 1528 1. 10 1 Electrifying -Machine as No. 1562 33. — 1 Discharger as No. 1594. 1. 75 1 Leyden Jar as No. 1598 1. 75 1 Electroscope as No. 1647 3. 50 1 Apparatus for decompo- sing water — as No. 1698 6. 75 1 Flask-Element asNo. 1727 8.25 Elecfro-Magnet as No. 1844 3. 50 Total Mk. 282. 30 The whole set of 50 apparatus 265. — C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 137 Set II for Superior Schools recommended of C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 2090. 1 Frick's Parallelogram as No. 2 11. 50 2091. 1 Frick's Inclined plane — as No. 19 16. 50 2092. 1 Archimedic Screw as No. 39 10. — 2093. 1 Stand with oue moveable and one fixed pulley . . . 11. 60 2094. 1 Frick's Lever- Apparatus as No. 65 8. 25 2095. 10 Bolognian- Flasks as No. 109 1. 75 2096. 25 Glass -Tears as No 110 1. 25 2097. 2 Adhesive Glass-Plates as No. 121 6. 50 2098. 1 Cartesian Swimmer as No. 287 1. 75 2099. 1 Nicholson's Weight Areo- meter as No. 293 ... . 5. 50 2100. Communicating - Vessels as No. 313 1. 75 2101. 1 Dutrochet's Endosmome- ter as No. 343 3. — 2102. 1 Segner's WaterWheel as No. 362 6. 50 2103. 1 Mariotte's Principle as No. 369 10. — 2104. 1 Suction-pipe glass-made, as No. 403 — . 90 2105. 1 Tantalus-Cup No. 413 . 3. 25 2106. 1 Heron's ball No. 429 . . 1. 75 2107. 1 Heron's fountain No. 433 3. 25 21C8. 1 Forcing pump No 444 . 3. 25 2109. 1 Fire-engine No 448 . . 4. 50 2110. 1 Air-Pump No. 474 .. . 22. — 2111. 1 Receiving Vessel No. 495 2.25 2112. 1 Testing Barometer with scale No. 501 3. 30 2113. 1 Ring for bursting bladders as No. 513 1. 75 2114. 1 Mechanism for showing that a siphon ceases to flow as soon as the ordinary pres- sure of air is lessened, as No. 525 2. 75 Mk. Pf. 2115. 2116. 2117. 2118. 2119. 2120. 2121. 2122. 2123. 2124 2125. 2126. 2127. 2128. 2129. 2130. 2131. 2132. 2133. 2134. 2135. 2136. 2137. 2138. 2139. 2140. 2141. 2142. 2143. 2144. 2145. 2146. 2147. 144. 8. 13. 10. 13. 3. brought forward: 1 lever-fountain as 527. . 1 falling-tube as No 534 . 1 breast-water-wheel as No. 610 10. 1 monochord as No. 801 . 1 apparatus, Chladni's soun- ding figures as No. 811. . 1 Angular mirror as No. 917 1 Caleidoscope No. 919. . 3. 1 Spherical mirror No. 941 4. Illustration of refraction No. 946 10. Crystal Glass-Prism No. 957 5. G lenses No. 977 6 1 optical model of the eye as No. 1099 1 thaumatrope as No. 1120 1 Magnifying glass with tripod-stand as No, 1159 . 1 telescope No. 1240 . . . 1 chemical thermometer . 1 pyrometer as No. 1329 . 1 Gay-Lufsac's weight-ther- mometer as No. 1345. . . 1 3 sheets-horse-shoe-load as No. 1524 70 25 25 25 25 25 6. 75 13. 25 2. — 2. 25 13. 50 4. — 5. — 5. 50 11. 4. 42, I, 2 2, 5, 5 9 75 75 1 compass-needle as 1526. 1 electrifying machine as No. 1563 1 discharger as No. 1594 . 1 Leyden Jar as No. 1598 1 Lightening tube No. 1614 1 Lightening plate No. 1615 1 Paper tuft No. 1617 . . 1 Bullet-rain No. 1620 . . 2. 75 1 flying wheel No. 1622 . 5. — 1 isolating chair No. 1633 6. — 1 apparatus for decomposing water No. 1698 6. 75 1 chromic acid flask element as No. 1727 8. 1 electro -magnet No. 1841 13. 1 electromagnetic hammer as No. 1857 16. 25 25 50 Total Mk. 409. 20 to ce carried forward: 144. 70 [ Price of the whole set, containing 58 apparatus 380. — 138 C. Gerliardt, Marquart's Lager cliemischer Utensilien, Bonn. Set III. for Superior Schools. recommended of C. Gerliardt, Marquart's Lager chemischer Utensilien, Bonn. Mk. Pf. 2148. 1 parallelogram as No. 2 . 11. 50 2149. 1 inclined plane as No. 19 16. 50 2150. 1 mechanism for explaining the screw as No. 26 . . . 2. 25 2151. 1 Model of an Archimedic screw as No. 39 10. — 2152. 1 screw and wheel as No. 40 8. 25 2153. 1 stand with moveable and fixed pulleys 16. 50 2154. 1 lever-apparatus as No. 66 16. 50 2155. 1 wheel on the axle as No. 74 6. — 2156. 1 Mechanism for explaining the equilibrium as No. 77 6. — 2157. 1 Mechanism for explaining the indifferent, stable and variable eqnilibrium as No. 79 3. 25 2158. 1 Cone-running-up-hill as No. 80 4. — 2159. 1 Chinese Stair climber as No. 82 3. 25 2160. 1 oblique tower as No. 91 4. 50 2161. 1 Column-scale as No, 95 22. — 2162. 1 Model of a weigh-bridge as No. 106 16. 50 2163. 1 Mechanism for demonstra- ting the elasticity of ivory — as No. 107 13. 50 2164. 1 Bolognian Flask asNo. 109 1.75 2165. 25 Batavian Glass-tears as No. 110 1. 25 2166. 1 pair of adhesive glass plates as No. 121 ... . 6. 50 2167. 1 falling-channel as No. 125 26. 50 21G8. 1 Centrifugal Machine as No. 147 27. 50 2169. 1 Ball-Regulator as No. 151 8.25 2170. Two Brass-balls as No. 155 4. 50 2171. 1 Glass-Balloon as No. 169 4. — 2172. lUustratioD of the difference between the longest and shortest diameter ol earth — as No. 185 G. 50 2173. 1 Apparatus Foucault's essay of pendulum — as No. 187 5. 50 2174. 1 Box-level as No. 247 . . 2. 75 to be brought forward: Mk. 255. .^0 2175. 2176 2177 2178. 2179. 2180. 2181. 2182. 2183. 2184, 2185, 2186. 2187. 2188. 2189. 2190. 2191. 2192. 2193. 2194. 2195. 2196. 2197. Mk. Pf. Carried forward: 255. 50 1 Pascal's Apparatus for measuring the pressure of ground — as No. 264 . . 27. 50 1 Illustration of buoyancy — as No. 276 2. 75 1 Apparatus for proving the Archimedic principle — as No. 282 5. 50 1 Weight Areometer as No. 293 5. 50 Communicating Vessels as No. 313 1. 75 10 Capillary-tubes on stand as No. 333 8. 25 1 Endosmometer as No. 313 3. — 1 Segner's 'SVater-Wheel as No. 362 6. 50 1 Apparatus for illustrating Mariotte's Principle as No. 369 10. — 1 Suction-pipe as No. 403 — . 90 1 triangular Suction - pipe with sucking-tube and stop- cock as No. 410 4. — 1 Heron's ball as No. 429 1. 75 1 Heron's fountain as No. 433 3. 25 1 Model of a Sucking-Pump as No. 441 2. 50 1 Model of a Sucking-Pump as No. 444 3. 25 1 Model of a lire-engine as No. 448 4. 50 1 Stop-Cock-Air-Pump with one chamber as No. 468 . 55. — 1 Receiving - Vessel as No. 495 4. 50 1 Barometer-test as No. 501 3. 30 1 Illustratiou of gravity of air — as No. 506 ... . 8. 25 1 pair of Magdeburg hemi- spheres as No. 517. ... 15. 50 1 Lever-fountain as No. 527 8. 25 1 Monochord as No. 801 . 10. — to be brought forward: Mk. 451. 20 C. Gerhardt, Mavquart's Lager cliemischer TJtensilien, Bonn. 139 Mk. Pf. Carried forward: 451. 20 2198. 1 Reflection - Apparatus as No. 90t5 13. 25 2199. 1 Angular mirror as No. 917 3. 25 2200. 1 Spherical mirror as No. 941 10. — 2201. 1 Illustration of reflection as No. 946 13. 20 2202. 1 Prism as No. 957 .. . 1. 25 2203. 1 Stereoscope as No. 1109 3. 30 2204. 1 dz. Stereoscope - Photo- graphs 3. 30 2205. iCameraobscuraasNo. 1135 13. 25 2206. 1 Microscope as No. 1170 20. — 2207. 1 dz. Microscopic-objects . 4. — 2208. 1 Lever - Pyrometer as No. 1324 10. — 2209. 1 Pyrometer as No. 1329 . 5. — 2210. 1 Compression-tinder-box as No. 1448 5. - 2211. 1 Heron's rotating ball as No. 1454 3. 25 2212. 1 Load-Stone as No. 1519 1. 25 2213. 2 Bertram's Load-Stones as No. 1520 6. 50 to be brought forward: Mk. 567. — Mk. Pf. Carried forward: 567. — 2214. 1 Horse - shoe -load, with 3 foils, as No. 1524 . . . 2215. 1 Compass - Needle as No. 152G 22 16. 1 Stand for it as No. 1528 2217. 1 Electrifying Machine as No. 1563 2218. 1 Apparatus to show the electric action of points as No. 1574 2219. 1 Distributing Conductor as No. 1585 2220. 1 Discharger as No. 1594. 2221. 1 Leyden Jar as 1598 . . 2222. 1 -Paper Tuft — as No. 1617 2223. 1 Flask-Element as No. 1727 2224. 1 Vertical-Galvanoscope as No. 1751 2225. 1 Electro-Magnet as No. 1841 2226. 1 Electro-Magnetic- Mallet as No. 1857 2227. 1 Index - Telegraph as No. 1872 11. — 1. 50 1. 10 42. — 5. 50 6. 75 1. 75 3. - 5. — 8. 25 13. 25 13. 25 16. 50 27. 50 Mk. 723. 35 Price of the whole set, containing 58 apparatus 680, — 140 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Set IV for Superior Schools recommended of C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. Mk, Pf. 2228. 1 Parallelogram of forces as No. 2 11. 50 2229. 1 Inclined plane as No. 19 16. 50 2230. 1 Illustration of the screw- as No. 26 2. 25 2231. 1 Pattern of a screw as No. 27 2. 75 2232. 1 Model of an Archimedic screw as No. 39 10. — 2233. L Screw and wheel as No. 40 8. 25 2234. 1 Apparatus for demonstra- ting the principles of the wedge — as No. 42 ... 13. 50 2235. 4 different pulleys with pul- leys and support — as No. 56 33. — 2236. 1 Lever-Apparatasa3No.65 8.25 2237. 1 Wheel on the axle as No. 74 6. — 2238. 1 Mechanism for explaining the stable equilibrium as No. 77 6. - 2239. 1 Mechanism for explaining the indifferent, stable and variable equilibrium as No. 78 2. 25 2240. 1 Cone running up hill as No. 80 4. — 2241. I Oblique tower as No. 90 2. 25 2242. 1 Model of an Unequal- armed-balance as No. 102. 9. — 2243. 1 Model of a weigh- bridge as No. 106 16. 50 2244. 1 Pair of adhesive glass- plates as No, 121 .... 6. 60 2245. 1 Falling-Channel as No. 125 26. 50 2246. 1 Centrifugal Machine as No. 146 24. 50 2247. 1 Ball Regulator as No. 151 8. 25 2248. 2 brass-balls as No. 155 . 4. 50 2249. 1 ball as No. 157 . . . . 8. 25 2250. 1 apparatus for demonstra- ting the difference between the longest and shortest dia- meter of earth — as No. 185 6. 50 2251. 1 Gyroscope as No. 200 . 16. 50 To be brought forward: Mk. 253. 60 Mk. Pf. Carried forward: 253. 50 2252. 1 Illustration of the laws of Pendulum as No. 210 . 6. 50 2253. 1 Grit-Pendulum upon stand as No. 220 16. 50 2254. 1 Box-Level as No. 247 . 2. 75 2255. 1 Illustration of the equal transmitting of pressure ia liquids as No. 251 .... 6. — 2256. 1 Pasqnal's Apparatus for measuring the pressure of ground as No. 261 ... . 27. 50 2257. I Illustration of buoyancy — as No. 276 2. 75 2258. 1 Cartesian - Swimmer as No. 287 1. 75 2259. I Weight Areometer as No. 293 5. 50 2260. 1 Cold-Water-Swimmer as No. 306 2. 75 2261. Communicating Vessels as No. 313 1. 75 2262. 1 Endosmometer as No. 343 3. — 2263. 1 Segner's Water-Wheel as No. 362 6. 50 2264. 1 Illustration of Mariotte's Principle as No. 369 .. . 10. — 2265. 1 Apparatus for showing that pressure is uniformly trans-mitted iu gases — as No. 398 5. 50 2266. 1 Glass -Siphon as No. 400 1. 25 2267. 1 Suction- Pipe as No. 403 — . 90 2268. I Heron's ball as No. 430 3. 25 2269. 1 Model of a Sucking Pump as No. 442 13. 60 2270. 1 Model of a forcing-pump as No. 445 22. — 2271. 1 Model of a fire-engine as No. 449 25. — 2272. 1 Stop-Cock- Air-Pump with one chamber as No. 468 . 55. — 2273. 1 Receiving - Vessel as No. 495 2. 75 To be brought forward: Mk. 475. 90 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 141 . Mk. Pf. Carried forward: 475. 90 2274. 1 Apparatus Gravity of air as No. 506 8. 25 2275. 1 Ring for causing bladders to burst — as No. 513 . . 1. 75 2276. 1 pair of Magdeburg hemi- spheres as No. 517. ... 12. 50 2277. 1 Lever-fountain as No. 527 8. 25 2278. 1 Falliag-tube as No. 534. 13. 25 2279. 1 India- Rabber-BaUoon as No. 558 2. 75 2280. 1 open labial Whistle as No. 755 5. 50 2281. 1 Labium, as No. 759 . . 5. — 2282. 1 Cagniard de la Tours Sirene as No. 784 ... . 13. 25 2283. 1 Monochord as No. 801 . 10. — 2284. 1 Apparatus Chladni's soun- ding figures as No. 811. . 13. 25 2285. 1 Tuning-Fork as No. 830 2. 25 2286. J Apparatus for showing, that light is transmitted in a straight line as No. 895 1. 75 2287. 1 Angular mirror as No. 9 IS 9. — 2288. 1 Spherical mirror as No. 941 10. — 2289. 1 Apparatus for illustrating reflection as No. 946 . . . 13. 20 2290. 1 Prism as No. 957 .. . 1. 25 2291. 1 optical bank as No. 979 15. 50 2292. 1 Model of the human eye as No. 1098 11. — 2293. 1 optical Model of the eye as No. 1099 13. 25 2294. 1 stereoscope as No. 1109 3. 30 2295. 1 dz. stereoscope - photo- raphs 3. 30 2296. 1 Thaumatrope as No. 1120 2. — 2297. 1 Camera obscuraasNo.il 35 13. 25 2298. 1 magnifying glass as No. 1157 2, 75 2299. 1 Microscope as No. 1170 20. — 2300. 1 dz. microscopical prepa- rations 4. — 2301. 1 open model of a terrestrial Telescope as No. 1245 . .11. — 2302. iTurmalin-TongasNo. 1293 13. 50 2303. 1 Chemical Thermometer as No. 1321 5. 50 2304. 1 Lever - Pyrometer as No. 1324 13. 25 2305. 1 Pyrometer as No. 1329 . 5. — 2306. 1 apparatus for showing the action of steam in steam engines 4. — 2307. 1 Differential-Thermometer as No. 1362 11. — 2308. lice-Apparatus as No. 1398 2.50 2309. 1 Water-hammer as No. 1406 1.75 2310. 1 Pulse-hammer as No. 1407 1. — 2311. 1 Compressions -tinder-box as No. 1448 ^ 5. — To be brought forward: Mk. 768. 95 Mk. Pf. Carried forward: 768. 95 2312. 1 Heron's rotating ball as No. 1454 3. 25 2313. 1 Apparatus for showing the conduction of the heat as No. 1458 6. 75 2314. 1 Davy's Safety -Lamp as No. 1462 8. 75 2315. 1 Depretz' Apparatus as No. 1465 40. — 2316. 1 Apparatus for essays about the conducting power of different liquids — as No. 1466 13. 25 2317. 2Concavemirror8asNo.l471 60. — 2318. 1 Thermoscop as No. 1473 2. 75 2319. 2 Bertram's load-stones as No. 1520 12. — 2320. morse-shoe-loadasNo.1524 11. — 2321. 1 Compass - Needle as No. 1526 2. 25 2322. 1 Stand for compass-needles as No. 1527 2. 75 2323. 1 Pair of astatic needles as No. 1542 6. 75 2324. 1 Inclination - needle as No. 1545 8. 25 2325. 1 Apparatus for determining the full effect of magnets as No. 1557 31. — 2326. 1 Electrifying Machine as No. 1562 82 — 2327. 1 Electrifying Machine as No. 1565 40. — 2328. 1 Apparatus for piercing ice as No. 1572 6. — 2329. 1 Apparatus to show the electric action of points — as No. 1574 5. 50 2330. 1 Apparatus Electricity at the surfaces of bodies as No. 1580 6. 75 2331. 1 Distributing Conductor as No. 1585 6. 75 2332. 1 Franklin's Platte as No. 1590 6. 75 2333. 1 discharger as No. 1595 . 4. 50 2334. 1 Leyden Jar as No. 1598 4. 50 2335. 1 Lane's measuring jar as No. 1612 13. 25 2336. 1 Paper -Tuft as No. 1617 6. 75 2337. 1 Bullet-raiu as No. 1621 5. — 2338. DancingPuppetsasNo. 1624 9. — 2339. 1 Electric Pistol as No. 1625 5.50 2340. 1 Isolating Chair as No. 1633 8.25 2341. 1 Carillon as No. 1634. . 11. — 2342. 1 Electroscope as No. 1647 6. — 2343. iKinnersley's Thermometer as No. 1653 22. — 2344. 1 Electrophore as No. 16 65 1 1. 50 To be brougth forward Mk.~T238. 70 142 C. Gerhardt, Marquart's Lager cheraisclier Utensilien, Bonn. 2345. •23-lG. 2347. 2348. 2349. 2350. 2351. 2352. 2353. 2354. 2355. 2356. Mk. Pf. Carried forward: 1238. 70 Amalgam as No. 1670 . . 1. 75 1 Electrometer as No. 1677 27. 50 Condensator - Plates as No. 1679 11. 50 1 Apparatus for decompo- sing salts as No. 1692 . . 5. — 1 galvanoplastical apparatus as No. 1694 6. 75 1 apparatus for decomposing water as No. 1697 .... 20. — 1 flask-element as No. 1725 16. 50 1 galvanometer as No. 1755 33. — 1 Oersted's Fundamental Essay as No. 1769. ... 13. 25 1 Ampere's frame as No. 1770 40. — 1 Apparatus, action of cros- sed currents as No. 1777 . 16. 50 1 Barlow's rotating wheel as No. 1785 16. 50 To be brougth forward Mk. 1446. 95 Mk. Pf. Carried forward: 1446. 95 2357. 1 Commutator as No. 1798 20. — 2358. I Thermoelectric Element as No. 1806 13. 25 2359. 1 Thermoelectric Column as No. 1822 40. — 2360. 1 Electro-Magnet as No. 1842 20. — 2361. 1 Electro -Magnetical Incli- natory as No. 1860 ... 33. - 2362. 1 Interrupting wheel as No. 1866 11. — 2363. 1 Morse - Telegraph as No. 1878 UO. — 2364. 1 Ruhmkorif's Coil-Inductor as No. 1910 45. — 2365. iGeissler'stubeasNo. 1917 1.75 2366. 1 do. „ „ 1918 2. 75 2367. 1 do. „ „ 1920 4. 25 Total Mk. 1747. 95 Price of the whole set, containing 140 apparatus 1650. — C. Gerhardt, Marquait's Lager chemischer Utensilicn, Bonn. 143 n e X. Xo. A. Absorbtiometer 563 Absorption of the caloric rays, tin-foil screw 1511 Absorption of gazes 561. 562 Achromatic lens 1019. 1020 Acoustic Dust-figures 782.783 Action of crossed currents upon another 1777 Action of magnets upon moveable currents 1773. 1774 Action of the magnet upon electric discharging in thin gases. . . 1904. 1905 Action of a rotating copper-disk on the compass needle 1899 Action of a spiral on magnets and soft iron 1869 Action of steam in steam-engines . . 1331 Adhesive Glass-Plates 121—123 Aeolian harp 806 Aeoline 816 Agricultural Machines 628—642 Air extends, when pressure is lessened 522. 523 Air Evacuation — Essay of Clement and Desormes 575 Air-Gun with Force-Pamp 557 Air-Pump, Accessories 497 — 547 Air-Pump-Stop-Colts 544—547 Air-Pump — Supplementary Parts 489—496 Air-Thermometer . 1356-1361, 1366-1473 Amalgam 1670 Ampere's Frame ....... 1770-1772 Analysis of oscillating frames .... 745 Anatomical Siphon 275 Anchor, double T 1947. 1948 Andrew's Press for condensing gases 1415 Anemometer 2031. 2032 Aneroide Barometer .... 386. 387. 2002 Angle of reflexion depends upon the angle of incidence 969 Angular mirror 917. 918 Angular Wheels 182. 183. 681 Anorthoscope 1126. 1127 Anthoscope 9^5 Aphaneidoscope 926 Apparatus for uniting the divided co- lours of the Spectrum . . . 1010. 1011 Arago, Action of a rotating copper-dislc on the Compass Needle 1899 No. Archimedio Principle 279-285 Arohimedic Screw 38. 39 Areometer-Scale 298. 304 Areometer-Weight 293. 297 Arragonite 1309 Astatic Needles 1511—1543 Atmosphere, the vapour contained therein 2028 Attraction and repulsion of curreuts . 1775 Attraction and repulsion of electric bodies 1577 Atwood's Fall Machine 126—132 Audibility, determing of its limits . 79—800 B. Babinet's Compensator 1296 Babinet's Stop- Cock . 546 Babo's bi-sulphuret of carbon lamp . 1082 Balances 93—96 — Chemical 96. 2478 — hydrostatical 289. 292 — unequal armed .... 102 — 104 Ball-Beam 176. 177 Ball for sprinkling essays by the means of freezing water. 1372 Ball indicating the centrifugal force 156. 157 id. same with weight 160. 161 Ball made of glass and wax .... 341 Ball-Regulator 150-153 Ball-Valve 659. 660 Barium-platina-cyanure .... 1080. 1081 Barlow's rotating wheel. 1785 Barometcrs-Aneroide 386. 387 — for demonstrations . . 376. 381 — Fortin's for travellers 1997. 1998 — made of metal (Aneroides). 2002 — with Mercury 382-385 — Nivelliug 388 — for Ships 20U Barometer-Siphon 1992—1996 — Standard 1992-1994 — Steam 1377 — testing for tlie air-pump 497—503 — variating 389 _ vessel 1999. 2000 Beam of a balance, modell .... 92. 93 Bellows hydrostatic 273. 274 id. 570. 750. 754 144 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. No. Berthollet's Experiment- gases mixiDg in equal ■volumes 564. 565 Bifilar-Uagnetometer 1559. 1560 Billet's Lens 12.54 Bismuth-Bullet 1934 Bi-Salphuret of carbou-lamp .... 1082 Bladder Valve G65. 666 Blower 2401-2103 Blowing table 747-749 Bohnenberg's Machine 197—199 Boiling point of fitiids . . 1318. 1319. 1393 Boiling of water or ether by rubbing 1450 Bolognian Flasks 109 Bound Electricity 1573 Bourdon's Ring 50i. 505 Bow Light Regulators .... 1956-1958 Bow triangle 6S6 Boxes 1203 Box-Compass 1762-1768 Box-Declination 1540 Box-level 247-249 Brachytelescope, Model of it .... 1248 Brass-balls of different weight. . . 154. 155 Brass-tubes 737 Brass-stands for Compass Needles 1527—1529 Brass- and Iron-Strips 1334 Breathed pictures, Moser's 560 Breitenbohner's Spirit-Lamp .... 1045 Brushes 1213 Bullets of Sun-Flower-Pith . . . 1645. 1646 Bullet-, Rain 1620. 1621 Bunsen's Gas-Lamp 1043. 1014. 2378. 2379 Buoyancy 276. 278 Bursting bladders ..... 513. 514. 554 C. Calcareous- Spar-Rhomboeder, dies and plates 1306. 1307. 1308 Caleidophon 824. 829 Caleidoscope 919. 924 Calorifer 1436 Calorimeter 1427. 1431. 1445 — -Mercury 1438 Calorimetric measuring of high tempe- ratures 1440 Camera lucida 1146. 1151 Camera obscura 1135. 1137 Capillary-Attraction, its measuring 337. 338 Capillarity, essays about it ... . 335. 336 Capillarity- attraction and repulsion produced by it 341. 342 Capillary-tubes 333. 334 Cardanish Suspension 84 Carbons 1959 Carillon 1634 Carre's Sulferic-Acid-Ice-Machine 1402. 1403 Cartesian Swimmer 287. 2?8 Centre of gravity obtained 203 Centrifugal Balance 158. 159 Centrifugal Force, depending on the velocity of rotation 162. 163 Centrifugal Force, proportionate to the square of velocity of rotation . . . 190 Centrifugal Machine 143. 147. 189. 1005 143. 147 — — Accessories for it 148. 189 — Pendulum 148. 149 No. Centrifugal Railway 191. 192 Chain, Ring, Cylinder 188. 189 Chaiu-Pump 656 Channel-semicircular 174. 175 Channel-Scale 316. 317 Changes of Spectra by reflection . . 1064 Chemicals for Spectral Essays. . 1036. 1057 Chemical Balance 96 Chemical Harmonica 726. 736 Chemical Spectra — objective demon- stration ■ 1066 Chemical Thermometer 1321 Chinese Stair-climber 82. 83 Chiadni's sounding figures .... 811. 812 Chronometric escapement 229 Circulation of heated water . . . 1350. 1351 Clack-Valve 657. 658 Clamps for elements 1739. 1744 Clement & Delorme's Essay . . . 573. 675 Clock-electric 1882 Clock-work for quick rotation of co- loured disks 1006 Coefficient of the refraction of gases. 964 Coefficient of extension 1327. 1328 Coefficient of the extension of mercury 1341. 1342 Cog-Wheel 682 Coherence of liquids 332 Coil-tubes 1051. 1052 Coil-Inductors 1906-1916 Cold-Water swimmer . . . 306a. 307a. 1349 Collodion-Ballon 559. 2376 Coloured Shadows 1132 Columns-thermo-electrical .... 1821. 1840 Columns of liquids, sounding and vi- brating 866 Coloured Disks 1004-1008 Coloured rings, Newton's .... 1264. 1265 Column of resistance 1791 Combination of heterogenous yibrations, which are swinging in a right angle 850 — 853 Combined movement produced by the continuous action of forces . . . . 17. 18 Communicating Vessels 313—315 Commutator 1798. 1805 Comparing of tuning-air-colamns by the means of manometric flames 780. 781 Compass 1538. 1539 Compass-Needles 1526 Compass-Needles, Universal, August's 1550. 1551 Compressibility of liquids 322. 324 Compression-Apparatus, Natterer's . . 1414 Compression-fountain 555 Compression-tinder-box 1448. 1449 Compressorium 1196 Concave lens 1510 Concave mirror, radiant heat .... 1471 Condensator 1651. 1661. 1679 Condensing of gases 1415 Conducting of heat, apparatus for it 1458-1461. 1466-1470 Conducting surfaces 1662 Cone-Mirror 945 Cone running up-hill 80 Cone-Valve 661. 662 Conical-Glass-Tubo 339. 340 C. Gerhardt, Marquart's Lager ehemischer Utensilien, Bonn. 145 No. Conical-Lens 1012. 1013 Conical Refraction, Lloyd's apparatus for it 1298 Connecting Chain 1640 Connecting Rods 1641 Contraction of heated be dies, when cooling 1332. 1333 Contraction of liquids 327. 328 Contrasting colours 1133. 1134 Cooling-Apparatus 1396. 1397 Copper-disc 1933 Copper-plate, silver plated 560 Copper- and Zincplate 1671 Corn-Squashing-Machine 641 Coulomb'sTurning-Balancell8.120. 1555.1556 Covering Glasses 1199. 1200 Crane 650 Crank 685 Crystal Plates 1302. 1304 Curtain of shirting 1237. 1238 Curves Lissajous 844 — 849 Curved Prism 956. 960-963 Cylinder 81 Cylinder escapement 671 Cylinder-ring and chain 188. 189 Cylinder running-up-hill 81 Cylindric blower 571 Cylindrical Mirror 943. 944 D. Dalton's Principle 1390-1392 Dancing Puppets 1624 Dasymeter 511. 512 Davy's Safety Lamp 1462 Debuscope 922 Declination-needle .... 1537. 1547—1549 Decomposition of salts 1692 — ofwaterl682— 1689— 1696-1698 Declination-box- compass 1540 Deep-measurer 90 — 91 Demonstrating-Balance 93 — -Barometer 376—381 — -Goniometer ... .927-929 Density of vapour, its determination 1408—1410 — of water, its maximum . . . 1348 Depretz, temperature diminishes in proportion to the distance of the heating source 1463—1465 Deviation of projectiles 582. 583 Diagonal machine 14—16 Diapason two tuning forks . . . .832—833 Dies of uranium -glass, didym -glass, fluor-spar, calcareous spar .... 1307 Diaphragm 1257 Difference between the longest and shortest diameter of earth .... 184 Difference between gases and vapours 1376 Difference between both electricities . 1576 Difference between the usual glass- reflection and the total reflection . 953 Differential-Pulley G3. 64 Differential-Reel 645. 646 Differential-Thermometer . . . .1362—1365 Diffraction-Apparatus 1255—1256 Diffusion of gases 566—569 No. Dilatometer 1343 Dipping battery 1728-1733 Discharger 1594—1597 Discharging-Electrometer 1674 Disjunctor 1887 Dispersing Apparatus 557 Distributing Apparatus 1586 — 1589 — Conductor 1535 Distribution of magnetism in magnet rods 1532. 1533 Diving bell 453. 454 Dobereiner's tinder box 455 Double Calorimeter 1431 Doable mill, resistance of air . . . 638. 539 Double knife 1207 Double Vessel-Air-Thermometer . . . 1366 Draw Beam-Model 652. 653 Drop-Glasses 325 Drying-Apparatus 178. 179 Dynamometer 115 — 117 Dynamometrical break 243 Dynamo-Electric-Eugine . . . .1944—1946 — Accessories for it 1947—1972 E. Bar-model 892-894 Eccentric catch . : 689. 690 Efflux of fluids through capillary tubes 361 Egg emptying into the receiving vessel 624 Elasticity of different vapours 1375. 1378— 1384. 1388—1392 Elasticity of ivory 107 Elasticity of metal wires 113. 114 Electric density 1579 — Clock 1882 — Condensator 1651 _ Egg 1668. 1669 — Endosmosis 1691 — mortar 1632 railway . . 1865. 1856. 1966—1969 — pendulum 1627 — pistol 1625 Electrical Machines 1562 — 1571 — — Accessories .1572—1670 _ _ Water Influence . 1570 — — with steam . . . 1571 Electricity at surfaces . . 1580—1583. 1657 Electro-Dynamo-Machine . . . .1944—1946 — — its accessories 1947—1972 Electrolysis of solutions of salts 1690—1707 Electrification of points .... 1574. 1575 Electro-Magnets 1841—1848 — for diamagnetical essays 1930—1932 — for diamagnetical essays 1930-1932 _ Accessories . . . .1933-1940 Electro-Magnetic-hammer . . . .1857—1859 — Inclinatorium . . . 1860 — rotating apparatus . 1861 — motor 1871 _ top 1850. 1851 swinging wheel . 1852. 1853 Electrometer 1638. 1639. 1643. 1654-1656 1673—1678 146 C. Gerhardt, Marquart's Lager chemischer Uteusilien, Bonn. No. Electromotoric-power produced, when solid and liquid conductors are brought into contact 1680 Electromotors 1854. 1862—1864 Electrophores 1663 — 1665 Electroscopes 1647 — 1650 Element. Glass 308 Elements of different kinds 1708—1716. 1718 —1727. 1734—1744 Element, thermo-electric . . . .1806—1816 Endosmometer 343 — 346 Endosmosis, influence of evaporation upon it 347 Eolipile 2374, 1455-2371 Equilibrium-Figures 75. 76 — indifferent, stable and changing 78. 79 Equilibrium of the elasticity of vapours 1383. 1389 — plateaux 326 — stable 77 Escapement by anchor 227 Etalon of the Unity of resistance, Siemens 1793 Ether inflamed 1631 Evaporating of ice in vacuo. . . 1412. 1413 — warmness of vapours . . 1443 Examining of volatile liquids .... 1703 Exciter for electricity 1653 Extension of air submitted to a con- stant pressure 1352 — 1384 Extension of air, when pressure is lessened 522. 523 Extension unequal of metals .... 1334 Extension of gases submitted to equal pressure, its co-efficient. . . . 1355. 1356 Eye human 1096—1101 F. Fall, parabolical of liquids .... 357. 358 Fall, parabolical of projectiles. . .139 — 141 Fall, the simultaneous of a body thrown in horizontal line and one falling free 142 Fall upon arc and chord 134 Fall upon various curved lines . .136—138 Fall-Machine, Atwood's 126—132 — Miiller's 133 Falling Channel 124. 125 Falling Tube 634-636 Faraday's Glass 1936 Felling for clearness diminishes under continuous action of light. .... 1128 Fenestrole 2028 Figeau's Interference-Apparatus . . . 1253 Fire-engine 448—461 Fire-fountain 1457 Flask-Bolognian 109 Flask with parallele walls. . . .1058—1060 Flights of theaters 18 Fluids, their parabolical fall . . . 357. 358 Fluorescence, essays about it ... . 1076 Fluorescent liquids, vans for them . . 1071 Fluorescing spectrum of the electric coil 1083 Fluorescing tubes . . 1084. 1085. 1925. 1926 Fluoroscope 1929 No. Flying wheel 1622. 1623 Force pump 548 — 552 Forcing pump 444 — 446 Foil Magnet 1525 Fortin's Barometer for Travelling 1997. 1998 Foucault's Essay of Pendulum 186. 187. 204-206 Fox-tail 16G6. 1667 Franklin's Plate 1590. 1592 Frauenhofer's Lines 1021 Freezing Apparatus . 532. 533. 1398—1401 — of Mercury ...... .1420—1423 — point at thermometers ... 1317 — thermometer 1368. 1369 Fresnel's Mirror Apparatus 1250 — Parallepiped 1297 Friction on inclined planes 242 Full effect of magnets 1557 Fundamental essay about induction . 1897 Fundamental essay. Oersted's . . . 1769 Fundamental essay, Volta's 1672 Fusing of a wire by means of an ice- block 1424 a. Galilei's Falling Channel 124. 125 Galvanic tuning 1870 Galvanometer 1752—1761 Galvanoplastical apparatus . . . 1694. 1695 Galvanoscope 1745 — 1751 Gas-Bottle 170. 171 Gas-burner, Bunsen's 1043. 1044 Gas-flame-manometer 777 — 779 Gas-indicator 568 Gas-lamp for the chemical harmonica 733-736 — for raonochromatical light . 1048 Gas-Motor 603—605 Gasometer 1232. 1233. 2399. 2400 Gay-Lussac's Apparatus . . . .1390—1392 Geissler's Tubes 19)7—1921 Glass-balloons 168. 169 Glass-balloon for determining the spe- cific weight of gases 1367 Glass-balls of different weight .... 305 Glass-Cylinder, stratification of water 1347 Glass-grate 1262. 1263 Glass-harmonica 823 Glass -model for Newcoman's steam engine 1452 Glass-plates with cemented magnets . 1634 Glass-presses 1300. 1301 Glass-rods 1214—1629 Glass-Siphon . . .400-411. 439. 440. 526 Glas-tears, batavian 110 Glass-tubes 1046-1635 Glass-tuft 108. 1618. 1619 Glass-wall-whistle 771. 772 Glasses for preparations 2450 Goniometer 927. 929. 930. 933 Gore's rotating ball 1784 Gramm glasses 309. 312 Graphic representation of the undula- tion of two tuning forks .... 888. 889 Grassmann's Stop-Cock 545 Gravity of air , . 506. 510 Gravity of gases, specific 572 C. Gerliardt, Marquavt's Lager chemischer Utensilien, Bonn. 147 No. Grubeaud's Freezing-Apparatus . . . 1374 Gun-lock 531 Gun-powder, inflamed 1630 Gyroscope 200—214 Gyrotrope 1797 H. Haldat's Apparatus for measuring the pressure of ground 270 Hare's Spiral • . . . 1717 Harmonica Chemical 726—736 — Glass 823 — Metal 822 Hat of platinum 1472 Hearing-trumpet 722. 723 Heart — its motion 687 Heating of air by compression . . . 1447 Heating and cooling of air by extension 1447 Heat and Cold produced by the electric current 1817—1820 Heat is produced, when gases are ab- sorbed 56] Heat produced by the galvanic current 1704 Heat produced in metal wires. 1705. 1706 Heliostate 911 916 Heron's ball 429-432. 526a. 1457 Heron's ball with forcing pump . 553—556 Heron's fountain 433-436 Heron's rotating ball 1454 Hook's Key 683. 684 Horse-Rake 639 Horse-Shoe-Magnet 1524. 1534 Hugi's freezing of cooling water. . . 1370 Hugi's freezing of water retarded . . 1370 Human ear, model of it ... . 892—894 Human eye 1096-1100 Hunter's screw-Press 37 Hydraulic Press 255—262 HydrauUc Ram 359. 360 Ilydrodynamic Wing 366—368 Hydrogen, Apparatus to make it . . 1231 Hydrostatical Balance 289—292 Hydrostatic Bellows 273. 274 Hygrometer ' . ■ 2003-2007 Hygroscope 2008 -2020 1. Jablochkoff's Candles 1972 Jamin's Foil Magnet 1525 Ice-Calorimeter 1427-1429 Ice, made liquid by strong pressure, Mousson'a 1373 Ice-Machine, Cane's with sulfuric acid 1402. 1403 Inclination-needle 1547—1551 Inclination and Declination needle 1 547 — 1551 Inclination of moveable currents . . 1787 Inclinatory 1898 Inclinatory-electro-magnetical .... 1860 Inclinatory-induction 1898 Inclinatory magnetical 1552 Inclined-Plane 19—25 Index-Telegraph 1872-1874 India-Rubber-Bag 1234. 1235 India-Rubber-ball with cork. . . 523. 558 No. India-Rubber rod 1628 Induction-Apparatus 1888 — 1893 Induction-Coils-juniping 1053 Induction-Cylinders 1883 Induction, fundamental essays about it 1897 Induction-Machine, magneto-electrical 1896 Induction-Spiral 1885. 1886 Induction of electric currents by tere- strial magnetism 1900 Influence-Machine 1565 — 1569 — of Water 1570 Injector 576 Intensity of terestrial magnetism 1558. 1560 Interference-apparatus, Figeau's . . . 1253 Interference-fork 880. 881 Interference, its phenomena, illustrated by Eisenlohr's apparatus 709 Interference and repulsion of waves . 698 Interference-prism 1251. 1252 Interference-tube 882. 885—887 Intermitting fountain 437. 438 Interrupting wheel 1866 Inverting of the natrium-line .... 1065 Joint-Lever 11. 12 Joint-Lever-Press 13 Iron- and Brass-strips 1334 Iron- und Steel-rods for magnetical distribution 1530 Iron-Powder 1535. 1536 Iron-Rod to prove terrestrial magne- tism 1531 Iron- Wire 1965 Isolating-brass-ball 1584 Isolating-chair 1633 Isolating-plate , . . 1637 H. Kibbling mill 642 Kinnersley's thermometer. . . . 1658. 1660 Knote-line 813. 815. 817 Koenig's whistle 773. 775 Kopp, specific warmness by means of the mixing method 1435 Kommerell's Apparatus to show the effect of friction upon inclined planes 242 Kryophon 1404. 1405 Kundt's Tube 782. 783 Kundt's Whistle 776 Labels 1202 Labial-Whistle 755. 758. 760. 766 Labium 759 Lament's box 1985 Lamps 2416-2423 Lane's measuring jar 1612. 1613 Larynx model of it 890. 891 Lehmann's Hot-Air-Machine . . . .601. 602 Lens-Apparatus 1002 Lenses 977.978. 1012. 1013. 1019a. 1020. 1254 Lenses optical, model of different kinds ^ 973. 976 Lens for ligthoning 1192 Levels 244-249 Lever-Apparatus 65. 71 148 C. Gerhardt, Marquart's Lager chemischer UtensiUen, Bonn. No. Lever-Barometer 1992. 1996 Lever-Fountain 527—529 Lever-Pyrometer 1324-1326 Leydentrost's essay 1394. 1395 Leyden Jars. . . . 1598—1606. 1608-1611 Liebig's Cooliug Apparatus . . 1396, 1397 Lightening plate 1615. 1616. 1643 Lightening tower 1626 Lightening tube 1614 Lightning jar 1607 Lloyd's Apparatus for conical refraction 1298 Load-Stones 1519. 1520-1525. 1532. 1534 Load-Stone, natural 1517. 1518 Locomotive, going 596. 598 Locomotive, profile-model of one .617. 623 Longitudinal vibrations 864. 685 M. Machine-Bohnenberg's 197 — 199 Machine, the Dynamo-Electric- 1944 — 1946 id. id. id. Acces- sories for these machines. . 1947 — 1972 Magdeburg-Brass-Hemispheres .... 517 Magic Carrel 426. 428 Magic can 420. 423 Magic funnel 415. 417 Magic lantern 1220 Magnesium -lamps 1152 — 1155 Magnetic attraction and repulsion 1555. 1556 Magnetic effect of discharging. . . . 1644 Magnetic curves 1534 Magnetic distribution, essays about it 1530 Magnetic distribution in magnets 1532. 1533 Magnetic inclinatory 1552 Magnetic top 1561 Magnetic polarity 1941 Magnetic thcodolit for the journey. . 1554 Magnetism terrestrial, its intensity 1558. 1560 Magnets, its full effects 1557 Magnetizing Spiral 1849 Magnetizing- and Induction-Spiral . . 1868 Magnetizing of steel rods 1867 Magneto - electric, rotating- apparatus 1894. 1895 Magnetometer 1553. 1559. 1560 Magnifying glasses . . . . 1156. 1167.2425 Manometer, Cosed with mercury. . . 397 — with gas flame . . . 777—779 Marine-Compass-needle 1539 Mariotte's Principle (376-381 see also accessories) 369, 381 Mascard's Isolated Stand 1652 Mechanism for inflaming gun-powder 1630 Measuring of electricity conduced to the negative pole 1693 Melloni's Thermo-Multiplicator . 1474. 1475 — — — Acces- sories for it 1476—1509 Membraneous tongue-whistle 877 Meridian circle, model of it 1249 Metal-barometer 2002 Metal-harmonica 822 Metal-thermometer 1336—1340 Metronome 222—223 Mica-Plates for '/, undulation . . 1311. 1316 Micrometer 1187. 1191 No. Microscope — Vibration ..... 854. 856 Mercury-air-pump 461—465 — calorimeter 1438 — rain 518—521 — apparatus to make it freeze 1420. 1422 Microphon 1903 Microscope, open model of a compound one 1242 Microscopy, accessories and utensiles for it 1186-1215 Microspical box 1185 Microscopical polarizing apparatus 1271 — 1273 Microscope — Sun -Microscope 1216 — 1219 Microtome 1209 Mid-day indicator 2039 Mirror-apparatus, Fresnel's 1250 Mirror conical 945 Mirror cylindrical 943. 944 Mirror galvanometer 1760 Mitscherlich's apparatus for permanent spectra 1049 Mixing of gases in equal voluniina 564. 565 Mixing of spectral colours, oscillating prism 1009 Model of a screw press 35. 37 Model of a water motore 606 Moment of inertia 207. 208. 209 Monochord 801. 805 Morse's telegraph . 1875—1880 Mortar electric 1632 Morser's breathed pictures 560 Motions taking place, when gases enter into a space filled with other gases 584. 586 Motor, electro-magnetical for rotating coloured disks 1007. 1008 Motor, electro-magnetical 1871 Moulds for the recongelation of ice . 1428 Mousson's apparatus to make ice liquid by strongest pressure 1373 Movable slit 1258 Miiller's fall machine 133 Multiplicator 1752—1761 ST. Natterer's-Compression-Apparatus . . 1414 Needles astatic 1541. 1543 Newton's Coloured ring 1264. 1265 O. Oblique towers 90. 91 Object-holders 1197. 1198 Observing lamps 1288. 1289 Observing tubes 1290. 1291 Ocular reversing 1186 Oersted's apparatus 322. 324 Oersted's fundamental essay 1769 Optical apparatus 1003 Optical bank 979-982 — — fittings for it . . 983—1001 — illussion, its illustration ... 1119 — model of the eye ... . 1099. 1100 Optometer 1104. 1105 Ozon-Tubes 1927 C. Gerliardt, Marquart's Lager chemischer Utensilien, Bonn. 149 No. Pachytrope 1796 Paper tuft 1617 Papin's pot 1385-1387 Papin's steam-piston 1331 Parabolical fall of projectiles . . 139—141 — — liquids 357. 358 — mirror 942 Parachute 579 Parallele piped, Fresnel's 1297 Parallelogram of forces 1—10 — Watts 688 Pascal's apparatus, pressure of ground 264. 265 Pendulum apparatus 210—221 Pendulum clock, open model . . 224—226 Pendulum electric 1627 Pendulum essay, Foucault's 186. 187. 204. 206 Penumbral- Polarizing-Apparatus . . 1281 Percussion-Apparatus 231. 235 Pfaundler's, the angle of reflexion de- pends upon the angle of incidence 969 — apparatus, specific warmness of liquids by means of the electric current 1437 Phonautograph 857. 860 Phonograph 861. 863 Phosphorescing- Glass-Clock 1094 — tubes 1086. 1087. 1924. 1928 — substances. . . . 1088. 1089 — of painting colors 1092. 1093 Phosphorescope 1090. 1091 Photographic apparatus 1138. 1139 — — chemicals for them 1140—1145 Photometer 897-805 Picnometer 312 Pincettes 1210. 1212 Pistol-air-pump 466—488 Pistol electric 1625 Planetary-Wheel for upright motion . 692 Plates- of plate-glass 342 Plates for air-pumps 489— 491 Plates of uranium-glass, didym-glass fluor-spar, calcareous spar, quartz, mica and gypsum 1072. 1075. 1308. 1310-1312. 1311 — 1315. 1314 Plate-valve 663. 664 Plateau's equilibrium figures .... 326 Plateau's apparatus, rotation of the earth-ball 329. 331 Plateau's disks for irradiation. . 1116. 1117 Platinum-hat 1472 Platinum-spiral 1963. 1964 Plettner's Relais 1881 Plough 628. 636 Pocket-Oompass-Needle . 1539 Polaristrobometer 12S6. 1287 Polarizing-Apparatus . . . 12G6— 1287. 1292 Polarizing-Caleidoscope ..... 923. 924 Polytrope 202 Powers mechanical 71a. 71b Preparing needles 1204 Preparing instruments case of. . . . 1215 Preparing tables 1143—1195 Presses . . 255. 262. 271. 272. 1236. 1415 No. Press for plants 259 Pressure, its equal transmitting in liquids _. 250. 284 Pressure of air, equal to all directions 515. 516 Pressure in fluids, growing with the depth 263 Pressure of fluids, from beneath . . . 286 Pressure of ground, its measuring 264. 270 Pressure uniform in gases .... 398. 399 Prisms 951. 953. 955. 963 965. 968. 1009. 1016. 1018. 1035 Progression and repulsion of waves . 697 Projecting-Apparatus 1216. 1229. 1278. 1960 Projecting-Caleidoscope 921 Projecting Wave-Machine 704 Propagation of heat in crystals, gypsum- plate for it 1470 Propagation of light, Eisenlohr's 710 —712. 895. 896 Pschyrometer 2021—2027 Puhy, mechanical equivalent .... 1451 Puhy, equivalent of heat 1451 Pulleys 54—64 Pulleys, movable or fixed 46 Pulley with dented wheel and mover 649 Pulley-weights 47. 48 Pulse-hammer 1407 Pyrheliometer 1973 Pyrometer 1324—1326. 1329. 1330 Quadrant Electrometer 1638. 1639. 1643. 1673 Quartz-Plates 1310. 1312 R. Radiometer 1512. 1516 Rain-bow, its arch, form .... 1014. 1015 Rain-measurer 2029. 2030 Ram G54. 655 Reaction of currents induced by mo- vement 1901. 1902 Real's press 271. 272 Receiver for thermopiles .... 1827. 1830 Receivers 495. 496 Recongelation of ice 1423 Reel 643. 646 Reflecting-circle 938. 939 Reflection ceases at the limits of media which have same refractive power. 954 Reflection complete in a jet of water 952 Reflection total, prism for it ... . 951 Reflection apparatus . . 236. 238. 906-910 Reflection galvanometer 1761 Reflection goniometer 930—933 Refraction apparatus . . . .946-949.1298 Refraction of light, mechanically imita- ted 971. 972 Refraction of light, moveable model . 970 Refraction of parallel glasses .... 950 Reaistering of the number of rotations ° 1970. 1971 Relais, Plettner's 1881 Relative warmness of difterent metals 1425. 1426 150 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. No. Repulsion of homonymons electricities 1578. 1593 Repulsion and interference of waves . 698 Resistance of air 537—539 Resistance of fluids 1699—1702 Resonators 875 Retort for making oxygen 1280 Reusch's rain-bow 1014. 1015 Reusch's refraction of light 970 Rheocord 1790 Rheostate 1788. 1789. 1792 Rhight-view-prism 1018 Ring-cylinder and chain 188. 189 Ring-Iron with magnetizing and in- ducing spiral 1868 Rhomboeder made of calcareous spar 1806 Rods of wood, 8 pieces sounding in accord 821 Roget's spiral 1776 Rosetti's figures 1642 Rost's pendulum, model 1335 Rotating apparatus, electro -magnetic 1861. 1894. 1895 Rotating ball, Gore's 1784 Rotating current under influence of another current 178S Rotating magnets or round magnets 1779-1783 Rotating mechanism 1938 Rotating mirror 739 -744 Rotating wheel. Barlow's 1785 Running strap 670 — 675 Rust pendulum 1385 Ryke's essay 738 S. Safety-Lamp, Davy's 1462 Safety- Valve 968 Saturated and overheated steam . . . 1411 Savart's apparatus, to show vibrations of sound between solid bodies. . . 878 Savart's wheels 797. 798 Scales 93-96 Scale- Areometer 298—304 Sciopticon. 1221-1225 Scheiner's Essay 1103 Scissors 1208 Schleiermachers Apparatus 190 Screen on stand 1259 1260 Screws . .■ 26-41. 678-680 Screw-Flyer 580. 581 Screw-jack 651 Screw-Turbine 613 Seeing with two eyes is a correct means for estimating distance. . . 1106 Segner's water-wheel 362 — 365 Semicircular chanel ....... 174. 175 Sensitized photographic paper. . . . 1095 Set I of apparatus , n „ „ ni „ , IV , Shaving-knife 120G Ship-pulley G47. 648 Siemens etalon of the unity of resistance 1793 Sieve of the Vestal 424. 425 Sine-box-compass 1767. 1768 No. Siphon ceases to flow, when pressure of air is lessened 625 Sirenes 784—798 Siphon-manometer 393. 396 Sliding apparatus 1884 Sliding condensator 1661 Slit moveable 1258 Sound-apparatus 540—543 Sound- vibrations between solid bodies 878 Sowing machine 638 Speaking trumpets 720. 721 Specific gravity of gases 572 — — of gases, glass-balloon for it . 1367 — — liquids ... .305 318-321 — warmness by means of the mixing method, Kopp's 1435 Specific warmness of liquids by means of the electric current 1437 Specific warmness of liquids by means of the cooling method 1439 Specific warmness of gases . . . 1441. 1442 Spherical mirror 940. 941 Spectral- Apparatus vz. Spectroscopes 1025. 1043 Spectral-Tables 1067. 1070 Spectral-Tubes 1054. 1922. 1923 Spectrometer 1022-1024 Spectrum of 7 phosphoring tubes . . 1928 Spiral band 1867 Spiral, Hare's 1717 Spiral, Roget's 1776 Spirit, lamp, Breitenbohner's .... 1045 Spring-Steel Yard 111. 112 Spring Drawer 164. 165 Sprinkling essays made with freezing water, iron ball for it 1372 Stability, its determination 85—89 Stable Equilibrium 77 Stable vibrations in closed tubes . 724. 725 Stair-climber 82. S3 Standard-Thermometer 1320 Standing undulations produced by the interference of direct and indirect waves 807 Stands for pulleys 50—53 — for prisms 959 — for holding glass -tubes .... 1047 — — spectral-tubes . . 1055 — for magnet-needles. . . .1527 — 1529 — for examining the coil-spectra 1050 — for mounting the eye of an ox 1102 — with copper disc 937 — for screwing wire .... 1961. 1962 Stauroscope 1299 Steam barometer 1377 — -cylinder, profile model. . .618—620 — -engine-models, going. . . .587 — 600 — -glass-model for explaining New- coman's steam-engine 1452 Steam-engine, profile model . . . .614—627 — — -piston 1331 — -ferry 1*56 — -heating-apparatus . . . .1432—1434 — -ram 655 — -reaction-wheel 1453 Steamer-model, going 599. 600 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. 151 No. Steel-rod on one same board .... 818 Steel-rod on one same brass board . 819 Steering of ships 9 Stereometer 390 Stereoscopes 1107—1115 Stratification of water, glass-cylinder for it 1347 Straight propagation of light . . . 895. 896 Stroboscope fitted for the sciopticon . 1123 Stroboscopic wave-disks 699. 701. 1121. 1122 Subjective Colours 1129—1131 Suction pipe 403—411 Sucking pump 441—443 Sun-Dial (Skiostate) 2035—2037 Sulfuric acid-ice-machine Carre's 1402. 1403 Sun-flower- piths-bullets 1G45. 1646 Sun-height-measurer 2034 Surfaces conductor 1662 Swinging siphon 172. 173 Swinging wheel, electro - magnetical 1852. 1853 T. Tack-fiddle 820 Tangent-box compass 1762. 1776 Tangent-electrometer 1656 Tantalus-cup 412—414 Taring-scale for pulleys 49 Telegraphs 1872. 1880 Telephon 719—1865 Telescopes 1239—1241 — open models .... 1243—1245 — mirror, model 1246. 1247 Telephon 719—1865 Temperature changes, when gases ex tend or are compressed 1446 Temperature diminishes in proportion to the distance of the heating source, Depretz's 1463—1465 Terrestrial magnetism .... 1558—1560 Testing disks 1636 Thaumatrope 1120 Theodolite magnetical for the journey 1554 Thermo-electric-column . . . 1821 — 1840 Thermo-electric-cross 1816 Thermo-electric elementl806. 1807. 1809. 1813 Thermo-electric-knot 1814. 1815 Thermo electric- rectangle 1808 Thermometer . . . .1320. 1323. 2469. 2471 — Air-Thermometer 1356. 1361 1473 — case 1986 — differential .... 1362-1365 — Freezing-Thermometer 1368. 1369 — Kinnersley's .... 1658—1660 — Maximum & Minimum 1977—1980 — to measure temperature of earth 1982—1984 Thermometer metal 1386—1340 1336—1340 — Pocket-thermometer . . . 1981 — scales combined 1322 — standard 1974—1976 — water-Thermometer. . . . 1346 — weight 1344. 1345 — for wells 1988 Thermo-Multiplicator 1474. 1475 Thermoscope 1473 Three-ways-stop-cock 544 No. Threshing-machine 640 Throttle-valve-model 152. 153 Thunder-house 1626 Tin-foil-screen 1511 To and fro motion by means of 3 half- dented-wheels 691 Toepler's Vibroscope 856 Tongue-Whistle 1425. 867-874 — — open 883. 884 Top 193-196. 1561. 1850. 1851 Toiirbillon electric 1575 Transversal swingings 809. 810 — waves 693 — 695 Traveller's theodolite, magnetic . . . 1554 — barometer 1997. 1998 Trevellian instrument 879 Tribometer 239-241 Tube for connecting with the air-pump 492—494 Tube-levels 244—246 — — of brass ,737 Tubes — with glass stopper .... 1061 — — filled with liquid carbonic acid 1416—1419 — for diamagnetical essays .... 1939 Tuning forks 830-843 Turbine 612. 613 Turmalin-tongs 1293-1295 Turning balance. Coulomb's 118. 120. 1255. 1256 Turning disk 1201 Turning of the polarizing plane by magnetizing powers 1942. 1943 Two-fields-harrow 637 Two tubes inclined to annother . . 166. 167 Tyndalls relative warmness of different metals 1425 V. Undulations of bent springs .... 808. 810 — of liquids 696 — of sound 706 Unequal arm balance 102 — 104 Universal caleidoscope 826 — 829 Universal compass needle, August's . 1550 V. Vacuum Incandescent lamps . 1949 — 1955 Valve model 657—669 Vapour atmospheric 2028 Varignon's table 8 Velocity of the efflux of fluids. . 348—356 Vertical calvanoscope 1749 — 1751 Vessel-barometer. . 1992-1994. 1999—2000 Vessel for observing absorption 1062. 1063 Vibration microscope 854. 856 Vibrations of minimal parts of ether iu polarized light 71 Vibrations tuning 866 Vibroscope 856 Voltameter .... 1682-16S9. 1696-1698 Volta's column 1681 Volta's fundamental essays 1672 Volumeuometor 391. 392 Vox humana 873 152 C. Gerhardt, Marquart's Lager chemischer Utensilien, Bonn. No. \¥. Washing minerals 180. 181 Water-air-pump 457. 460 Water-hammer 1406 Water-fet-blower 456 Water-influeDce. electrical- machine . . 1570 Water or ether boiling by rubbing, Tyndall's 1450 Water-thermometer 1346 Water-wheel 362. 365. 607. 611 Watt's Ball-Regdator 150. 153 Watt's Parallelogram 688 Wave apparatus 715. 716 Wave channel 705 Wave-Disk-Stroboscope 699—701 Waves longitudinal 707. 70S Wave-machine 713. 718 Wave pictures 702. 703 Wave-projecting-machine 704 Wedge, — illustration of 42 — 45 Wedges of gypsum, plates 1313. 1314. 1470 Weigh-bridge 105. 106 Weight-areometer 293. 297 No. Weights for scales 97--101 Weigths for pulleys 47. 48 Weight thermometer 1 344. 1345 Werthheim's apparatus, sounding vibrations 866 Wheatstone's bridge 1794—1795 Wheel and pinion 676. 677 Wheel on the axle 72. 74 Wheel reacting against air ... . 530. 578 Whistles for blowing tables and bellows 755. 776. 867. 879 Whiskes of same tune 770 Whole warmness of steam 1444 Widow's the oil-cruet 418. 419 Wilds-wind-flag 2033 Wing hydrodynamic 366—368 Winged wheel, to show the resistance of air 539 Wire grate 1261 Woods metal 1371 Z. Zootrope 1124. 1125