ii CONTENTS. 



JUNE 1802. 



Engravings of the following Objects : 1. Strong framed Levers for Steam En- 

 gines, by Mr. J. C. Hornblower, and others; 2. Diagrams by Dr. Young, 

 to explain the Nature and Properties of Light; 3, 4. Figure by Mr. Gre- 

 gory to demonftrate Mr. Pearfon's Analogy for deducing ths greateft Equa- 

 tion from the Eccentricity : and another by Mr. Gough, for fhewing how we 

 perceive the direction or' Sound. And, 5. Anew Lamp by Melfrs. Caret! and 

 Carreau, in which the Oil is raifed mechanically. 



J. On the Rev. Mr. Pearfon's Analogy for deducing the greateft Equation 

 from the Eccentricity. In a Letter from Mr. Olinthus Gregory. Page 65 



II. On the Conftruclion of the Beams of Steam Engines. By Mr. J. C. Horn- 

 blower. From the Author. - - 68 



HI. On the Theory of Chemiftry. In a Letter from the Rev. J. Prieftley, 

 L. L.D.F. R. S. &c- .... 69 



IV. Experiments upon the tanning Principle, and Reflections upon the Art of 

 Tanning. By Cit. Merat Guillot, Apothecary at Auxerre. 70 



V. On the Defhuction of the Grub of the Cock-chafer. By Edward Jones, 

 Efq. of Wepre-Hall, in Flint/hire. - 73 



VI. Methods of diminifhing the Irregularities of Time-Pieces, arifing from 

 differences in the Arc of Vibration of the Pendulum. By Mr. Ezekiel 

 Walker. - - - - .76 



VII. On the Theory of Light and Colours. By Thomas Young, M. D. 

 F. R.S. Profeffor of Nat. Philof. in the Royal Inftitution. - 73 



VIII. Remarks on Combuftion. By T. Thomlbn, M. D. Lecturer on Che- 

 miftry in Edinburgh. - - - 92 



IX. A Continuation of the Experiments and Obfervations on the Light which 

 is fpontaneoufly emitted from various Bodies; with ibme Experiments and 

 Obfervations on folar Light, when imbibed by Canton's Phofphorus. By 

 Nathaniel Hulme, M. D. F. R. S. and A. S. (Concluded from page 40.) 100 



X. Defcription of a Lamp upon Argand's Principle, with Improvements, in 

 which the Oil is maintained at the lame Level by the conftant Action of a 

 Pump. By Citizens Cared and Carreau - - 108 



XI. Note upon a peculiar vegetable Principle contained in Coffee. By 

 Richard Chenevix, Efq. F. R. S. M. R. I. A. From the Author. 114 



XII. Account of fome Experiments performed upon a Scale of confiderable 

 Magnitude, and principally by the Agency of Froft, to produce Sulphate 

 of Soda, Carbonate of Magnefia, and Muriate of Ammonia, from Sulphate 

 of Magnefia, Carbonate of Ammonia, and Muriate of Soda. By H. Camp- 

 bell, M. D. From the Author. - - - 117 



XIII. Note of Citizen Vauquelin refbe&ing the Boracite, called Magne- 

 fio-calcareous Borate by the French Chemiils. - - 120 



XIV. Facts and Obfervations tending to explain the curious Phenomenon of 

 Ventriloquifm. By Mr. John Gough. - - 122 



XV. An Analyfis of a Mineral Subftance from North America, containing 

 a Metal hitherto unknown. By Charles Hatchett, Efq. - 129 



XVI. Remarks on the Mamoth. By Louis Valentine, Phyfician in Chief cf 

 the Army and Hofpitals of America, of feveraj National and Foreign So- 

 cieties, refident in Nancy. - 138 



Scientific News. Prizes of the National Inftitute of France — Afironcmical 

 Prize — Communications to the Royal Society reflecting the Planet Ceres—* 

 Leonardo da Vinci—Experiments to prove that all Bodies, whatever may 

 be their Nature, are obedient to the Action of Mao-netilin, and that this 

 Action is lulBcienny powerrih to aqmit or being meafuredj 141 to 143 



JULY 



