Dr. Thomson s Answer to the Review of the [Apeil, 



ta the Eacyclonscdia Britannica, to his article Chemistry in the 

 same book, and to some of liis prefaces in the Royal Institutioa 

 Journal. In point of diffuseness, want of energy, and bad taste, 

 these dissertations constitute a perfect contrast to every thing 

 which ever flowed from my pen. Indeed were 1 disposed to 

 criticise style, nothing would be easier than to retaliate upon 

 Mr. Brande. 



As to the nature of my own style I am very willing to let it 

 rest upon the four papers which the Reviewer has stigmatized in 

 the passage just quoted. These papers, with which the Re- 

 viewer in fact had nothing to do, occupy 67 pages of the Annals 

 of Fliilosophy. They contain the details of my experiments to 

 determine the specific gravity of 21 gases, and the atomic 

 weights of 13 important bodies. I had to discuss the experi- 

 ments of preceding writers, and to endeavour to point out the 

 causes of the difference between their results and mine. Thus 

 every individual substance occupies, at an average, almost 

 exactly two pages. All these experiments were made with a 

 degree of care and attention, which, I confidently affirm, has 

 never been surpassed. In opposition to the Reviewer's state- 

 ment, that ** there is scarcely a single determination of Dr. 

 Thomson's on any chemical subject of difficulty, during the last 

 eight years, which has not been reversed,'^ (p. 122.) 1 venture 

 to assert that the determinations in these four papers, and in 

 several more since published, will withstand all the attacks of 

 Mr. Brande, however violent and long continued they may be ; 

 that they belong to one of the most difficult and most important 

 parts of chemistry ; that they are essential to the very founda- 

 tion of the science ; and that they have established the atomic 

 theory upon a foundation which cannot be shaken. 



** 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 a great number 

 of chemical facts, with copious references, 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." — 

 (Review, p. 121.) 



The inference, I presume, which the Reviewer wishes to be 

 drawn is, that Mr. Brande's little elementary work, or his article 

 Chemistry in the Supplement to the Encyclopaedia Britannica, 

 is entitled to be called a System of Chemistry ; and that the 

 same name may be bestowed upon the new edition of Nicholson's 

 Dictionaiy. 



The attack upon my arrangement awakened my curiosity, 

 and induced me to turn to Mr. Brande's article Chemistry m 

 the Supplement to ihe Encyclopaedia Britannica* As 1 expected 



