ANNALS 



OF 



PHILOSOPHY. 



JULY, 1818. 



Article I. 



History of physical Science from the Commencement of the Year 

 1817. Part I. By Thomas Thomson, M.D. F.R.S. &c. 8cc* 



CHEMISTRY. 



1 HIS science has been, since our last historical sketch, advanc- 

 ing with its usual rapidity. And as the analytical methods have 

 of late years been very much improved, and much more attention 

 is at present paid to precision than was formerly the case, more 

 confidence may be put in the researches of Aose chemists at 

 least who have acquired the requisite skill. lrus is one among 

 the many advantages which has resulted from the general diffu- 

 sion and adoption of the atomic theory. I shall, as usual, arrange 

 the different new facts under general heads, as such a distribu- 

 tion tends considerably to facilitate the recollection, while it 

 enables the reader more readily to perceive which department of 

 the science has been cultivated with the greatest industry and 

 success. 



I. LIGHT AND HEAT. 



1. Magnetizing Power of the Violet Rays of the solar 

 Spectrum. — Our readers will probably recollect that M. Mori- 



• The change that took place in the Editorship of the Annals of Philosophy at 

 the close of the last year, and the engagements of Dr. Thomson during the winter 

 and spring, in his new situation at Glasgow, necessarily interrupted the plan that 

 had been before adopted, of appropriating a part of the January number to an 

 account of the progress of science for the preceding year. The history of chemistry 

 has now been completed by Dr. Thomson, and is here presented to our readers ; 

 the account of the progress of the other departments of physical science will be 

 given in a subsequent number. 



Vol. XII. N° I. A 



