218 
ON POISONS. 
ART. XLII. — VIEWS OF PROFESSOR LIEBIG ON POISONS, 
CONTAGIONS, AND MIASMS. 
[The following interesting remarks on the modus 
operandi of poisons, &c, prepared for the "British Associ- 
ation for the advancement of Science," byDr. Playfair, at the 
request of Professor Liebig, contain the new views of the lat- 
ter on this subject. — A. S.] 
Poisons may be divided into two classes, belonging to the 
inorganic and organic kingdom. Many substances are called 
inorganic poisons, which have in reality no claim to be con- 
sidered as such. Sulphuric, nitric, and muriatic acids, when 
brought in contact with the animal oeconomy, merely destroy 
the continuity of the organs, and may be compared in their 
modus operandi to the action of a heated iron, or a sharp 
knife. But there are others — and these are the true inor- 
ganic poisons — which enter into combination with the sub- 
stance of the organ without affecting any visible lesion of 
them. 
Thus it is shown, that when arsenious acid or corro- 
sive sublimate is added to a solution of muscular fibre, cellu- 
lar tissue, or fibrin, these enter into combination with them, 
and become insoluble ; when they are introduced into the 
animal organism the same circumstance must happen. But 
the bodies formed by the union of such poisons with animal 
substances, are incapable of putrefaction ; they are incapable, 
therefore, of effecting and suffering changes ; in other words 
organic life is destroyed. The high atomic weight of animal 
substances explains the cause of such small quantities being 
requisite for producing deadly effects 
To unite with 100 grains of fibrin, as it exists in the hu- 
man body, (in which it is combined, with 30,000 parts of 
water,) only 3i grains of arsenious acid are necessary, or five 
grains of corrosive sublimate. 
