78 Notices respecting New Books. 



In the chapter of Earths, each earth is first separately 

 described, with its distinguishing characteristics; then the 

 origin of each; and, lastly, its uses in the arts and ma- 

 nufactures. In the subsequent chapters the alkalies, acids, 

 oxides, and salts, are treated in an equally perspicuous 

 manner. The chapter on Metals occupies 7 L 2 pages, and is 

 thus divided. First we have the characteristics of metals in 

 general, how tbey are procured and purified, and how classed 

 bv modem chemists, llach metal is then separately treated 

 of under five distinct heads, thus: — " How is platina pro- 

 cured? What is the nature of platina? What is the effect 

 of oxygen on platina? What salts are formed of platina? 

 What arc the uses of platina?" Direct answers are given 

 to each of these questions, which are further elucidated by 

 a large body of very valuable and learned notes. The chapter 

 concludes with an interesting recapitulation of the general 

 properties of that class of bodies. 



A few extracts from the Notes to this excellent work, we 

 trust, will not be unacceptable to our readers. Thus in the 

 chapter on Air: " Every chemist must be aware that a large 

 quantity of carburttted hydrogen gas is evolved at the sur- 

 face of the earth; he must also know that this gas is fatal 

 to animal life. I could adduce a melancholy instance of a 

 gentleman who inhaled it by mistake, and died almost im- 

 mediately in consequence of it. How then has the all-wise 

 Artificer of the world contrived to protect its inhabitants 

 from the baneful influence of that immense quantity with 

 which the atmosphere is perpetually contaminated ? The 

 means are as simple as they are important. Vegetables arc- 

 so constituted that curbon and hydrogen are the necessary 

 food of plants, and conduce to the support of vegetable life: 

 their vegetating organs seize the carbonic acid gas which 

 comes within their reach, and, while they appropriate the 

 carbon to theuuelves, the oxygen is thrown off to renovate 

 the atmosphere by its union with the nitrogen rejected by 

 animal respiration. Thus, what is noxious to man is -ren- 

 dered beneficial to vegetables; and the oxygen, which vege- 

 tables are not in want of, is separated by them in its utmost 

 purity for the use of man." In the chapter on Water the 



following: 



