ON THE HISTOUY OF TEIlRESTItf A t PHVSICS. 753 



■pile was constructed by j\fr. Carlisle, and its singular effects in tlie decompo- 

 ^sition of water were jointly observed by himself and Mr. Nicholson. The 

 original existence of animal electricity, as asserted by Galvani and Volta, 

 has been in some degree confirmed by the experiments of Aldini, the nephew 

 of Galvani. A number of detached observations, of considerable merit, have 

 also been made by Pfaff, Ritter, Cruikshank, Wollaston, Fourcroy, and many 

 other chemists, both in this country and on the continent. But Mr. Davy's 

 late experiments must be considered as exceeding in importance every thing 

 that has been done upon the subject of electricity, since the discovery of 

 the pile of Volta. The conclusions which they have enabled him to form 

 respecting the electrical properties of such bodies as have the strongest ten- 

 dencies to act chemically on each other, and the power of modifying and 

 counteracting those tendencies which the electric fluid possesses, have 

 greatly extended our views of the minute operations of nature, and have 

 opened a new field for future investigations. I hope that I shall be par- 

 doned by astronomers for having inserted, on this occasion, in a vacant space 

 among the constellations, in the neighbourhood of Pegasus, the figure of a 

 galvanic battery ; which nuist now be allowed to have as great pretensions 

 to such a distinction as the electrical machine and the chemical furnace. ^ 



The late experiments and speculations of Mr. Dalton, on various subjects, 

 belonging to different branches of physics, have tended to place some parts 

 of the science of meteorology in a new light. It is true that many of his hy- 

 potheses are very arbitrarily assumed; some of them are manifestly contrary 

 to experiment, and others to analogy and probability; at the same time his 

 remarks appear in some cases to be either perfectly correct, or to lead to de- 

 terminations which are sufficiently accurate for every practical purpose. I have, 

 attempted to borrow from Mr. Dalton's ideas some hints, which I have incor- 

 porated with a less exceptionable system; and by a comparison of his experi- 

 ments with those of many other philosophers, I have deduced some methods 

 of calculation which may perhaps be practically useful; in particular a sim- 

 ple rule for determining the elasticity of steam, and a mode of reducing the 

 indications of hygrometers of different kinds to a natural scale. 



Count Rumford's establishment of a prize medal, to be given every three 



