38 OF CARBON. 



it is merely an admission of our ignorance in 

 not knowing what circumstances are neces- 

 sary for their production, or in not being 

 enabled as yet so to arrange such circum- 

 stances, so as to produce them. 



In its gaseous state, as carbonic acid gas, 

 carbon is invisible, and has a sour sharp smell 

 and taste. It is destructive of all animal life, 

 not so much apparently from any noxious 

 quality it possesses as from the absence of a 

 due quantity of oxygen to support the vital 

 functions. It is constantly met with, in old 

 wells, brewers' casks, &c. and may be pro- 

 duced at pleasure by mixing a small quantity 

 of whiting or marble with strong vinegar or 

 dilute sulphuric acid, when an effervescence 

 immediately takes place, and the gas so libe- 

 rated, is tolerably pure carbonic acid gas. 



The results of the ultimate analysis of va- 

 rious vegetable substances is here given, that 

 it may be seen how important a part in the 

 vegetable economy carbon performs, and that 

 the importance attached to it, in this work, is 

 not overrated ; and it must be here impressed 

 forcibly on the reader, that no substance what- 

 ever can be produced in plants unless the ele- 

 ments composing it are present, and that al- 

 though plants possess the power of decom- 

 posing one substance, and combining one of its 

 component parts with another substance, or in 

 different proportions with the same matter it 

 was previously combined with, and thereby 

 producing a new compound differing materially 



