ii CONTENTS. 



OCTOBER, 180k 



Engravlns:« of the following Ohjefts : 1. An Apparatus for Filtration, by Sir 

 H. C. Engleficld, Bart. Sec. F. R. S. j '2. Stiufliire for purifying an entire 

 Stream of Water; 3. Very fiinple ftriking Part for a Clock, by Mr. Prior j 

 4. An Inftrunient for counting rhe Number of Draughts from a Mine, by 

 Mr. Antis ; 5. An Inftrument f r delineating in Perfpeftive ; 6. Cheap Ap- 

 paratus for drawing Ovals; 7. Sketch of Mr. Mai ton's Method of niaking 

 very large Port-folios for Drawings and Prints. 



I. Extraft of a Letter from Count Apollos de Mouflin Pouflikin to Charles 

 Hatchett, Efq. F. R. S. defcribing his Method of preparing Malleable Pla- 

 tina. Communicated on the Requeft' of the Count, by Charles tfa*^cliett, 

 Efq. F. R. S. andnowfirrtpubliflied _ _ . Page 63 



II. On Pepper. By Thomas Thomfon, M. D. Communicated by the Au- 

 thor - ----- 68 



III. Letter from the Abbe Buee on Mr. Rome de Lifle's and the Abbe Hauy's 

 Theories of Cryftallography - • - _ . 78 



IV. Obfervations on Mr. Gough's Striftures on the Doftrine of Mixed Gafes, 

 &c. In a Letterfrom Mr. J. Dalton - - - 89 



V. Account of the Striking Part of an Eight-Day Clock. By Mr. John 

 Prior, cfNefsfield, Yorkfliire. Communicated to the Society of Arts 92 



VI. On the Coft of making Phofphorus. In a Letter from J. P. - 94- 



VII. On the Purification of Water by Filtration; with the Defcription of a 

 fimple and cheap Apparatus, In a Letter from Sir Henry C. Englefield, 

 Bart. F. R. S. &c. - - - - - 95 



VIII. Experiments on the EfFe6ls of Heat modified by Compreflion, by Sir James 

 Hall, Bart. Read in the Royal Society of Edinburgh, Auguft30, 1804. Com- 

 municated by the Author - - - - 98 



IX. Atmofpherical Air not a mechanical Mixture of the Oxigenous and Azotic 

 Gafes, demonftrated fiom the Specific Gravities of thefe Fluids. In a Letter 

 from Mr. John Gough - - - - 107 



X. Letter from Thomas Young, M. D. F.R.S. &c. announcing the Difcovery 

 of a new jnoving Star, by Mr. Harding, of Lilienthal j and on other Sub- 

 je^s - - - - - - 112 



XI. Defcription of an Inftrument to afcertain the Number of Lifts made from 

 a Mine, m any given Time. By Mr. John Antis - 114 



XII. On Galvanifm. In a Letter from Ra. ThicknefTe, Efq. - K'O 



XIII. Defcription of an Inftrument for drawing in true Perfpeftive from Na- 

 ture, an^l of another of confiderable Simplicity and Cheapnefs for deline- 

 ating Ovals. In a Letter from a Currefpondent, R. B. - liJ2 



XIV. On the Computation of Tables of Squares and Cubes. In, a Letter from 

 H. G. - - - - - - 123 



XV. Letter to the Editor from Mr. William Henry, in Reply to Mr. Gough 126 

 XVi. Defcription of a very fimple and cheap Contrivance for making Port- 

 Folios of large Dimenfions. By the late James Malton, Efq. - 128 



XVII. Experiments and Calculations relative to Phyfical Optics. By Thomas 

 Young, M. D. F. R. S. From the Phil. Tranf. for 1804 - 130 



Scientific News, Account of Books, &c. 141— National Inftitute Prizes, lb. — 

 Extraft of a Lettei- from Profeflbr Bode, Aftronomer Royal, to Mr. A. F. Tho- 

 elden, 142— Kxtrafl of a Letter from Mr. G. B. Greenough, 143— Organic 

 Remains of a former World. An Examination of the Mineralized Remains 

 of the Vegetables and Animals of the Antediluvian World, generally termed 

 Ksttraneous Follils. Bv James Parkinfon, Hoxton, 143. 



NOVEMBER, 



