Chapters in this book

1. Frontmatter I
2. CONTENTS XXIX
3. I A LETTER from Dr. B. Franklin, to Dr. Ingenhaufz, Phyfician to the Emperor, at Vienna, on the Caufes and Cure of Smokey Chimneys 1
4. II. Explanation of an Optical Deception, by Mr. Rittenhoufe, 37
5. III. Defcription cf the White Mountains in New-Hampfbire, by the Rev. Mr. Jeremy Belknap 42
6. IV. Defcription of a remarkable Rock and Cafcade, near the IVeJlern Side of the Youghiogeny River, by Tho. Hutchins, Efq. 50
7. V. Letter to- Mr. Nairne, of London, from Dr. Franklin, propofing a flowly fenfible Hygrometer for certain Purpof 51
8. VI. Defcription of anew Stove for burning of Pitcoal, and confuming all it's Smoke, by Dr. Franklin 57
9. VII. A Theory cf Lightning and Thunder Storms, by Andrew Oliver, Efq. of Salem, in the State of Maffachufetts 74
10. VIII. Theory of Water-Spout's, by Andrew Oliver, Efq. 101
11. IX. Experiments on Evaporation, and Meteorological Obfervations made at Bradfeld in New-England, by the Rev. Samuel Williams, A. M. 118
12. X. A Letter from J. Madifon, Efq. to D. Rittenhoufe, Efq. containing Meteorological Obfervations, 123
13. XI. Defcription of a Machine for meafuring a Ship's Way thro' the Sea> by F. Hopkinfon, Efq. 159
14. XII. Account of an EleBrical Eel, or the Torpedo of Surinam, by William Bryant, Efq. 166
15. XIII. Obfervations on the Numb Fifh, or Tbrporific Eel, by Henry Collins Flagg, of South-Carolina, 170
16. XIV. A Letter to David Rittenhoufe, Efq. from John Page , Efq. 1 7 3 From David Rittenhoufe, Efq. to John Page, Efq. 173
17. X V . Defcription of the Grotto at Swatara, by the Rev. Peter Miller, of Ephrata ; communicated by William Barton, Efq, 177
18. XVI. An Account of fome Experiments on Magnetifm, in a Letter to John Page, Efq. at JVilliamfburg, from Mr. Rittenhoufe 178
19. XVII. New Method of placing a Meridian Mark, in a Letter to the Rev. Dr. Ewing, Provoft of the Univerftty. By D. Rittenhoufe, Efq. 181
20. XVIII. Account of a Worm in a Horfe's Eye, by F, Hopkinfon, Efq. 183
21. XIX. An improved Method of Quilling a Harpfichord, by F. Hopkinfon, Efq. 185
22. XX. Obfervations on a Comet lately difcovered; communicated by David Rittenhoufe, Efq. 195
23. XXI. ExtraB of a Letter from the Rev. Jeremy Belknap, containing Obfervations on the Aurora Borealis. 196
24. XXII. A Letter from J. Madifon, Efq. to D. Rittenhoufe, Efq. containing Experiments and Obfervations upon -what are commonly called the Sweet Spring 197
25. XXIII. A Letter from the Rev. Jeremy Belknap, on the prcferving of Parfnips by drying. 199
26. XXIV. An Optical Problem, propofed by Mr. Hopkinfon, and folved by Mr. Rittenhoufe, 201
27. XXV . An Enquiry into the Caufc of the Increafe of Bilious and Intermitting Fevers in Pennfylvania, -with Hints for preventing them. By Benjamin P»ufh, M. D. Profeffor of Chemiftry in the Univerfity of Pennfylvania 206
28. XXVI. An Account of the late Dr. Hugh Martin'* Cancer Powder, -with brief Obfervations on Cancers. By Benjamin Rufh, M. D. &c. <bc 212
29. XXVII. Mayeri Obfervationes AJlranotnica 217
30. XXVIII. Obfervations on the Caufe and Cure of the Tetanus, by Benjamin Ruih, M. D. ire. <bc 225
31. XXIX. Letter concerning Chimneys, addreffed to His Excellency Benjamin Franklin, Efq. L. L. D. Preftdent of the State of Pennfylvania, and of the American Philofophical Society, ire. by Dr. Rufton, 231
32. XXX. Obfervations on the annual Paffage of Herrings, by Mr. John Gilpin 236
33. XXXI. Obfervations on a Solar and Lunar Eclipfe, communicated to the Socwty by M. M. de Granelviin, Major-General of the French Squadron 239
34. XXXII. An Account of the Tranfit of Venus over the Sun, June 17 69, as obfervetl at Newburyin Majfachujetts; by the Rev. Samuel Williams, A. M. 246
35. XXXIII. An. eafy and accurate Method of finding a true Meridian Line, and thence the Variation of the Compafs. By- Robert Patterfon 251
36. XXXIV. Aftronomical Obfervations, communicated by Mr. Rittenhouf 260
37. XXXV. A Letter from Mr. Otto to Dr. Franklin* "with a Memoir on the Difcovery of America 263
38. XXXVI. The antifeptic Virtues of Vegetable Acid and Marine Salt combined, in 'various Diforders accompanied ivith Putridity ; communicated in a Letter to JOHN MORGAN, M.D. F. R. S. and Profejfor of the Theory and Practice of Phyfic at Philadelphia 284
39. XXXVII.. Medical Hiflory of the Cortex Ruber, or Red Bark ; communicated to JOHN MORGAN, M. D. Profeffor of the Theory and Practice of Phyfic at Philadelphia 289
40. XXXVIII. A Letter from Dr. Benjamin Franklin to Mr. Alphonfus le Roy, Member of feveral Academies at Paris, containing fundry Maritime Obfervation 294
41. XXXIX. Account of two Hearts found in one Partridge 331
42. XL. Conjectures concerning Wind and Water Spouts, Tornados and Hurricanes. Communicated by Dr. John Perkins, of Bofton, to John Morgan, M. D. èrc. òc. 335
43. XLI. The "whole Procefs of the Silk Worm, from the Egg to the Cocon ; communicated to Dr. John Morgan, esc. at Philadelphia, in two Letters from Meffrs Hare and Skinner, <bc. in London, July 27, 1774, and February 24, 1775 347
44. XLII. The Art of making Anatomical Preparations by Corrofion. By John Morgan, M. D. éc. ebc 348
45. XLIII. Of a living Snake in a living Horfe's Eye, and of other unufualProduttions of Animals. By J O H N M O R G A N , M D. F. R. S. London,, Profefjor of the Theory and P rail ice of Phyfic, Philadelphia. 383
46. XLIV. Some Account (fa motley coloured, or pye Negro Girl and Mulatto Boy, exhibited before the Society in the* Month of May, 1784, for their examination^ by Dr. JOHN MORGAN, from the Hijlory given of them by their owner Monf. Le Vallots Dentift of the King of France at Guadaloupe in the Weft Indies, as follows. 392
47. XLV. Extratt of a Letter from BERNARD ROMANS, of Penfacola, dated Auguji 20, 1773 396