Thomson's System of Chemistry. 121 



minent place. Our press pours forth, almost annually, rudi- 

 ments, catechisms, elements, principles, manuals, dictionaries, 

 systems of chemistry, and conversations on it, in great pro- 

 fusion ; of which the successive editions prove the demand for 

 them to be constantly renewed. We have, at least, six respect- 

 able chemical compilations, by different persons, while the French 

 nation are satisfied with one treatise, that of M.Thenard. 



Over all the British compilers. Dr. Thomson claims prece- 

 dence. Some of the others are content to transcribe from his 

 collection, but he seldom or never condescends to pay any of his 

 brother compilers a similar compliment. Possessing the minute 

 patience of an index framer, rather than the enlarged capacity of a 

 systematist, he has contrived to bring together, in his successive 

 editions, a great number of chemical facts, with copious refer- 

 ences, convenient to the student, and imposing on the general 

 reader ; but in our opinion not entitling his work to be called a 

 System of Chemistry. The account of this science which he 

 drew up for the supplement to the Edinburgh Enccylopcedia, 

 which appeared about 1800, presents all the peculiar qualities 

 of Dr. Thomson's manner of writing, and is by far the best com- 

 pend of chemistry which he has yet offered to the public. When 

 the detail of pheenomena is condensed within such a compass, 

 his scholastic divisions and subdivisions on the Peripatetic plan, 

 answer very well ; and form a convenient catalogue raisonnee 

 of the facts. But we think that he has failed on attempting to 

 extend that sketch into a system. Whenever he begins to gene- 

 ralize, his technical decision of manner leaves him, and, to the 

 surprise of the readers of those clear details, which he had 

 merely transcribed from experimental chemists, he becomes ob- 

 scure and contradictory. To this defect, a more serious fault 

 has been added ; and which, progressively gaining force, has of 

 late grown almost intolerable ; we mean, the preference of hy- 

 pothesis to fact on innumerable occasions, so that it is difficult 

 for the experienced chemist, and impossible for the tyro, to dis- 

 tinguish between them in his works. 



In his earlier editions. Dr. Thomson was content to transcribe, 

 with decent fidelity, the researches of practical chemists, and thus 

 acquired deserved reputation as a compiler. When, however, 

 he commenced his Annals of Philosophy, he assumed a new 

 character ; erecting himself into a supreme judge of all scientific 

 publications, he dealt forth his praise and censure with a dog- 

 matism, very imposing on superficial minds. His annual sum- 

 maries of chemical improvements apportioned to each chemist 

 his share of public reputation ; and though flimsy and incorrect, 

 were regarded by tyros, as specimens of singular sagacity. 

 Even these, however, have since found out, that keenness of 

 temper is not synonymous with philosophical acumen; for there 



