73 



ORGANIC CHEMISTRY. 



^ If our improved chemistry should ever discover the art of 

 making sugar from fossile or aerial matter, without the assistance 

 of vegetation, food for animals would become as plentiful as water, 

 and mankind might live upon the earth as thick as blades of grasSj 

 with no restraint to the increase of their numbers, but the want of 

 local room."* After having recovered a little from the astonish- 

 ment which this singular passage may have excited, perhaps, in the 

 jMalthusian^ not tinmingled with the dread of " mankind living 

 upon the earth as thick as blades of grass," and the horror of mul- 

 tiplying, not merely to " the starving point," but to the absolute 

 want of room whereon to fix a local habitation, we shall find, on 

 quietly contemplating the subject, that, absurd as Darwin's idea 

 confessedly is, it would be by no means easy to demonstrate the im- 

 possibility of raising food from inorganic matter. Tannin, or that 

 peculiar matter contained in barks, which, by combining with, the 

 gelatine of skin, forms leather, is as strictly a vegetable production 

 as sugar, and yet^, by a circuitous process, may be formed from " fos- 

 sile or aerial matter," and even from matter altogether inorganic 

 in its origin. We have, however, no intention of attempting to 

 prove the plausibility of Darwin's suggestion, but shall confine our 

 remarks to some of the singular, and even startling changes which 

 chemical processes effect in organic substances. " Saw-dust itself 

 is susceptible of conversion into a substance bearing no remote ana- 

 logy to bread, and though certainly less palatable than that of flour, 

 yet no way disagreeable, and both wholesome and digestible, as 

 well as highly nutritive."t This is calculated to excite surprise, 

 " but when persons not familiarized with chemical speculations are 

 told that a pound weight of rags can be converted into more than a 

 pound weight of sugar, they may regard the statement as a piece of 

 pleasantry, though nothing, says M. Braconnot, can be more real." J 

 Let us, then, study a few of the changes produced in organic mat- 

 ter by the action of heat, moisture, and other agents. As the num. 

 ber of organic substances is, however, far too great for present exa- 

 mination, we will confine our attention to two only — the woody 

 fibre of vegetables, and the muscular fibre, or fibrin, of animals. 



Woody fibre, in a state of purity, that is, after every substance 



• Botanic Garden^ add. note xxxix, to part i. 

 •f" Herschell's Discourse on Natv/ral Philosophy. 

 X Ure's Dictionary of Chemistry. 



