62 Analyses of Books. (\July, 



different proportions produce a mere oxide, an alkali, or an acid, 

 with the same base. Mr. Topham will find that he has incor- 

 rectly stated with respect to different proportions of oxygen, 

 what is true only with regard to different bases. This erroneous 

 view of the case is also contained in the chapter on oxides, in 

 which it is stated that " any simple substance, in union with a 

 less quantity of oxygen than is necessary for the formation of 

 an acid, is termed an oxide." Now acidity does not depend upon 

 the quantity of oxygen, but upon the nature of the base which 

 unites with it. Six parts of carbon combined with 16 of oxygen 

 form an acid, but 6 parts of hydrogen combine with 48 of oxygen 

 to form water. In the next chapter we again meet with the erro- 

 neous statement that sulphuric acid is formed by the combustion 

 of sulphur over water; and sulphurous acid is said to be " con- 

 stituted of 1 atom sulphur and 2 of oxygen in 100." We would 

 inquire whether it is not so constituted in 10, 100, or 1000 parts? 

 or whether its atomic constitution is altered by the quantity sub- 

 jected to analysis, so that what is true of two portions of 50 parts 

 each added together would not be true of 100 parts ? 



Nitric acid is said to be a compound of one atom of nitrogen 

 and two of oxygen, instead of five of oxygen ; but carbonic acid 

 Is one of the most extraordinary we have ever met with : " it is 

 widely diffused through nature, being combined with chalk, 

 limestone, gypsum, magnesia, &c." Of these four statements, 

 one only is correct ; chalk and limestone are not combined with 

 carbonic acid, they consist of lime combined with it, and gypsum 

 is neither combined with, nor contains carbonic acid; we need 

 hardly say, that it consists of sulphuric acid and lime. 



In speaking of nitrous oxide, it is stated to consist of " two 

 atoms of nitrogen and one of oxygen." We suspect that 

 our author has mistaken volumes for atoms ; for this gas, 

 although composed of two volumes of nitrogen and one volume 

 •of oxygen gas, is generally allowed to consist of only one atom 

 .of each. 



It appears from Exp. 4, that our author does not know that 

 -nitric oxide and nitrous gas are different names for the same 

 elastic fluid ; for he says at p. 64, nitric oxide on coming into 

 contact with atmospheric air receives a further portion of oxygen, 

 and becomes nitrous gas. 



We have neither time nor inclination to pursue our observa- 

 tions upon this work any further ; and after what we have stated 

 it would be superfluous to offer any additional opinion respecting 

 it ; but we cannot refrain from expressing our surprise, that a 

 gentleman who must have distinguished himself in order to have 

 acquired the degree of Master of Arts, should so far have for- 

 gotten what was due to his own reputation and to public utility, 

 as to venture to write a book upon a subject, his ignorance of 

 which he must have felt, and all conversant with chemistry 

 must discover. — (P.) 



