Thomson's Si/btem of Chemistry . 160 



fore, that muriatic acid is tlie appropriate solvent of the oxide 

 of antimony ; a fact of which Dr. Thomson seems ignorant, 

 though he transcribes the process, of which this fact is the 

 ground-work. ' 



His directions for procuring pure antimony, are of a piece 

 with the above. " Antimony may be dissolved in nitro-muriatic 

 acid, and precipitated by the affusion of water. The preci- 

 pitate is to be mixed with twice its weight of tartar, and fused 

 in a crucible. A button of pure antimony is obtained *" If 

 bismuth be present in the antimony, the two metallic oxides 

 will go down together, and a buttmi of pure antimony will not 

 be obtained. Nay, further, suppose the antimony associated 

 with tin, it is impossible to separate the Invo metals, by solution 

 in nitro-muriatic acid, and affusion of water; for the oxide of 

 antimony carries down with it, in a state of coinbinaLion, a 

 large quantity of oxide of tin. See Annales de Chivne, Tome 

 55, p. 276. 



On his fourth volume we need not enter into details. It is 

 the same abstract from books of natural history, mixed up 

 with a little chemistry, as we found in his former editions. The 

 carelessness with which it is reprinted is conspicuous in the 

 very first paragraph. " Vegetables," says he, " are too well 

 known to require any definition. They are, perhaps, the most 

 numerous class of bodies belonging to this globe of ours; the 

 species already known, amounting to no less than 30,000, and 

 very considerable additions are daily making to the number f." 

 If we look into his analysis of Bonpland and Humboldt's 

 " Nova genera et species plantarum," in the Annals of Philo- 

 sophy for May 1816, we find him stating, that " Botanists at 

 present are acquainted altogether with 44,000 species of plants ; 

 while the whole number, mentioned by the Greeks, Romans, and 

 Arabians, does not exceed 1,400 |." 



A considerable part of the fourth volume is professedly 

 devoted to physiology, or an examination of the physical 

 functions of living beings, vegetable and animal. How mawkish 

 the composition is, the following average specimen will shew. 

 " Why do plants die? This question can only be answered 

 by examining, with some care, what it is which consti- 

 tutes the life of plants ; for it is evident, that if we can dis- 

 cover what that is which constitutes the life of a plant, it 

 cannot be difficult to discover whatever constitutes its deaih. 

 Now the phenomena of vegetable life are, in general, vegetation. 

 As long as a plant continues to vegetate, we say that it lives ; 

 when it ceases to vegetate, we conclude that it is dead^." 

 This is after all untrue, as he immediately begins to recollect; 

 for vitality exists in a seed or root, without active vegetation. 



* SijuUm, III. (iai. t ll'i'l-. IV. 1. 



; Ibid., |)a(?e 374. j Ihlil., IV. ,JCil. 



