iv CONTENTS. 



AUGUST 1SC2. 



Engravings of the following Objects: 1. Figures to illuftratc Mr. JamefunV 

 Obiervations on the Formation of Granite; 2. Mr. Banks's luftruments for 

 determining the PreflTurCS and Velocities of effluent Air or Gas ; 3. The Spirit 

 Hydrometer and Scales of Atkins; 4. Compound Condenfers of Electricity, 

 by Mr. Read and Mr. Cuthbertfon. 



I. On Granite. By Mr. Robert Jamelbn. Communicated by the Author. 



Page 225; 



}1. Obfervations on the Conversion of Iron into Steel. In a Letter from Jofeph 

 Prieftley, L. L. D. F. R. S.&c. &c. ' - - - 233 



JII. An Account of the Art of making Glue. In a Letter from Mr. John 

 Clennel. - - - - - - 235 



IV. On the Preparation of Indelible Ink. In a Letter from Mr. Thomas Shel- 

 drake. - - - - - - 231 



V. Obfervations on the Caufes why a large Quantity f common Salt pre-* 

 vents Putrefaction, and a fmall Quantity haflens it. By D. H. 249 



VI. Account of the Methods by which Soda is at prefect prepared for the 

 Englifh Market j with other Obfervations. By Mr. Fred. Accum. From 

 the Author. - - - - - 24) 



VII. Comparifon of the French definitive Metre with an Englifh Standard* 

 brought from London by M. A. P idler, one of the Editors of the Bibliotheque 

 Britannique. '- - - - - 244 



VIII. On the Figure of Sulphate of Barytes, and the Formation of Man^ 

 drcporce. In a Letter from Mr. H. Sarjeank - - 253 



IX. Experiments and Obfervations on certain ftony and metalline Subfhnces, 

 which at different Times are faid to have fallen on the Earth; alio on va- 

 rious Kinds of Native Iron. By Edward Howard, Efq. F. R. S. From; 

 the Philofophical Tranfaftions. 1802. - - - 254 



X. An Anfwer to Mr. Gough s EfTay on the Theory of Compound Sounds. 

 By Thomas Young, M. D. F. R. S. - - - 26* 



XI. Experiments on the Velocity of Air iffuing out of a VefTel in different Cir- 

 cumftances; with the Defcription of an Inftrument to meafure the Force cf 

 the Blaft in Bellows, &c. By Mr. Banks, Lecturer in Natural Fhilofo- 

 phy. - - - -' 269 



XII. On the Variation of Rate in a Time Piece, as indicated by the Changes in 

 the Arc of Vibration. In a Letter from Mr. Ezekiel Walker. 273 



XIII. Defcription of Atkins's Hydrometer for afcertaining the fpecific Gra- 

 vities of fpirituous Liquors. By J. Fletcher, Efq. Communicated by the 

 Author. - - - - 21ci 



XIV. An Examination of Sig. Volta's Experiments which he calls funda- 

 mental, and upon which his Theory of Galvanifm refts; with a Defcription of 

 a very fenfible Electrical Condenfer, and an Explanation of the Airion of 

 the Electric Fluid in the Galvanic Inflrument. By John Cuthbertfon, Phil 

 lofophical Inftrument Maker, No. 54. Poland Street, London. Communi- 

 cated by the Author. - - - - 281 



XV. Obfervations on the Phofphorefcence of the Tremolite, and of the cal- 

 careous Phofphate of flow Solution, known by the Name of Dolomie. By 

 M. Ie Comte de Bourn' n, Fellow of the Royal and Linnaean Societies. 

 Tranflated from the Original; communicated by the Author. 290 



XVI. Outline of the Hiftory of Galvanifm; with a Theory of the Action of 

 the Galvanic Apparatus. By John Boftock, M. D. From the Author. 29§ 



