NATURAL HISTORY. 
281 
Gluten .—Forms a ductile, elastic mass, with water; partially 
soluble in water; precipitated by infusion of nutgalls, and oxegeri- 
cycae nuriatic acid; insoluble in alcohol; by fermentation becomes 
viscid and adhesive, and then assumes the properties of cheese 
soluble in nitric acid, and yields oxalic acid. 
Albumen .—Soluble in cold water; coagulated by heat, and be¬ 
comes insoluble; insoluble in alcohol; precipitated by infusion of 
nutgalls; soluble in nitric acid ; soon putrifies. 
Gelatine .—Insipid; soluble in water; does not coagulate when 
heated ; precipitated bv infusion of galls. 
Wood .—Composed of fibres; tasteless; insoluble in water and 
alcohol; soluble in weak alkaline laxivium; precipitated by acids; 
leaves much charcoal when distilled in a red heat; soluble in nitric 
acid, and yields oxalic acid. 
Fibrin. —Tasteless; insoluble in water and alcohol; soluble in 
diluted alkalies, and in nitric acid; soon putrifies* 
By this analytical survey, in which I have been minute on ac¬ 
count of the future inductions, we may observe that, but the starch, 
fibrin and wood, are soluble in water, and the gluten partially so. 
We also find that the gluten, which remains undissolved, forms a 
ductile elastic mass with the water; and, besides, becomes viscid and 
adhesive by fermentation, and then assumes the properties of cheese. 
We discover that the albumen and the fibrin soonputrify. Thus we 
have, as the component parts of vegetable matter, four soluble sub¬ 
stances, three insoluble, one partially soluble; and of these, two soon 
putrify. Besides these, we have, according to a more accurate 
chemical analysis, the elastic products or gases, carbon, hydrogen, 
and oxygen; nitrogen is a constituent principle of several, and the 
fixed and volatile alkalis are also found. Having now decided the 
component parts of the matter or subject in question, we come to the 
process by which it is decomposed, and the agent employed. The 
process is maceration, and the agent water. 
Maceration is that process by which a body is steeped in a cold 
liquor. It does not differ from digesting, excepting that the term is 
never used when the temperature of the mass is raised beyond that 
of the surrounding air. On the nature and phenomenon of the pu¬ 
trefactive process in vegetable matter, we have the following excel¬ 
lent account in Rees’ Encyclopaedia: 
“ The conditions necessary for the putrefaction of vegetables are 
similar to those required in the putrefaction of animal substances. 
It is necessary that the organization be impregnated with water; the 
contact of air is necessary, as also a certain degree of heat; and for 
