ON POISONS. 
219 
The second class of poisons are those belonging to the or- 
ganic kingdom. For some such substances as bruciaand strych- 
nia, no data exists by which it can be determined to what 
cause their action may be assigned. But the morbid poisons? 
such as putrid animal, and contagious matter, appear to owe 
their action to a peculiar agent, which exerts a much more 
general and powerful action than chemists are aware of. 
Thus when oxide of silver is thrown into peroxide of hydro- 
gen, the oxide is reduced and metallic silver remains. Here 
there can be no affinity, for oxygen can have no affinity for 
oxygen. 
It is merely that a body in a state of motion or decomposi- 
tion is capable of inducting or imparting its own state of mo- 
tion or decomposition to any body with which it may be in con- 
tact. There is a disease frequently produced in Germany, 
by using decayed sausages as an article of food. The symp- 
toms attending the disease are remarkable, and distinctly 
indicate its cause. The patient afflicted with the disease be- 
comes much emaciated, dries to a complete mummy, and 
finally dies. The muscular fibre, and all parts similarly 
composed, disappear. The cause of the disease evidently 
is, that the state of decomposition, in which the component 
parts of the sausages are, is communicated to the consti- 
tuents of the blood, and this state not being subdued by the 
vital principle, the disease proceeds, until death ensues. 
It is remarkable that the bodies of the individuals who 
have died in consequence of it, are not subject to putre- 
faction. 
The cause of the action of contagious matter is similar. 
It is merely a gaseous matter in the state of transforma- 
tion, and capable of imparting the state of transposition, 
in which its atoms are, to the elements of the blood. It is 
capable of being reproduced in the blood, just as yeast 
causes its own reproduction in fermenting wort. The 
causes of the action of yeast and of contagion are considered, 
by Professor Liebig, to be the same, and he has produced 
examples, in which similar reproductions take place, in 
