ii CONTENTS. 



FEBRUARY 1803. 



Engravings of the following Objects : 4. Dr. Wollafton's Method of examining 

 the refractive and difperfive Powers of Bodies; 5. Mr. Hooke's Blow-pipe by 

 Alcohol j 6. The harmonic Sliders of Dr. Young ; 7. A ftrong and flexible 

 Joint for Pipes tranfmitting Steam or comprefled Fluids. 



J. Anfwer to the Obfervations of Mr. William Cruickfhank upon the Doctrine 

 of Phlogifton. In a Letter from the Rev. Jofeph Prieftley, L. L. D. F. R. S, 



Page 65 



II. The Conrtruction of an Apparatus for conducting Sound and holding Con- 

 verfation at a Diftance. In a Letter from Mr. Ezekiel Walker. - 69 



III. Obfervations in Reply to Mr. Gough's Letter on the Grave Harmonics. 

 In a Letter from Thomas Young, M. D. F. R. S. &c. - - 72 



IV. Experiments and Obfervations on the Power of Fluids to conduct Heat; with 

 Reference to Count Rumford's Seventh EfTay on the fame Subject. By John 

 Dalton. --------75 



V. A Method of examining refractive and difperfive Powers, by prifmatic Re- 

 fleaion. By William Hyde Wollafton, M. D. F. R. S. - - 89 



VI. An Account of Dr. Young's Harmonic Sliders. From his Paper in the 

 Journals of the Royal Inftitution, p. 261. - 101 



VII. Obfervations on the Appearances produced by the Collifion of Steel with 

 Hard Bodies. By Mr. Davy, Lecturer on Chemiftry at the Royal Inftitu- 

 tion. -------- 103 



VIII- Defcription of a Blow-pipe by Alcohol, having a fafety Valve, with other 

 Advantages. Constructed by Mr. Benjamin Hooke, Fleet-Street. - 106 



IX. Defcription of a Joint applied to Tubes ufed for conveying Steam under 

 confiderable Preffure. W. N. - - - - 107 



X. Memoir on Achromatic Glaffes adapted to the Meafure of Angles, and the 

 Advantages that may be derived from double Refraction for the precife Mea- 

 furement of fmall Angles : by Alexis Rochon, Member of the National Infti- 

 tute, and Director of the Naval Obfervatory at Breit. - - 110 



XI- Obfervations on the two lately difcovered Bodies. By Will, Jlerfchel, 

 L. L.D. F. R. S. - t - - - - 120 



MARCH 



