90 NATURE AND LIFE. 
The case with morbid humors is the same as with mor- 
bid tissues. They are derived from healthy humors by 
similar processes, and they contain no principles foreign to 
the system—only they are produced in places where they 
should not be produced, and in a proportion which ac- 
counts for the disorders they bring on. The fluids of the 
various dropsies, for instance, proceed from hypergenesis 
of normal serous products, which are extracted from the 
blood by serous membranes, such as the pleura and the 
peritoneum. Pus is formed by a blastema issuing from the 
subcutaneous cellular tissue, and within which the white 
globules originate." The contents of the various liquid 
cysts are similarly produced at the expense of the blood- 
plasma by a true hypersecretion. These morbid humors 
do not rid the system of some subtile and noxious principle, 
as it used to be taught; they form under the effect of an al- 
teration of the blood, of some disturbance of circulation, or 
of irregularity in the acts either of secretion or of excretion. 
Ancient physiology and ancient’ medicine have by 
turns preached solidism and humorism, that is to say, the 
exclusive predominance either of the solids or of the 
fluids, in the effecting of vital phenomena. Neither of 
these systems is sustained by facts. ‘The tissues and the 
humors play equally active and important parts in the or- 
ganism, and disease has its source in the alterations which 
occur in the latter, as well as in disturbances affecting the 
1 Some authors who had heretofore believed that globules of pus grow 
by proliferation out of the elements of the tissue called the conjunctive, 
have of late found themselves obliged to give up that explanation, 
which conformed too to the cellular theory, and they have adopted an- 
other extremely ingenious one, which consists in assuming that these 
globules come from the blood, without, however, having ever proved how 
they are produced in that blood. Besides, they forget too to explain 
how, in certain cases, collections of pus form in which there are five or 
six times as many leucocytes as there were in the whole mass of blood 
that served to form them. 
