764 
ANALYSIS OF CONTINENTAL JOURNALS. 
II. Determination of the physical condition of virulent agents. 
With regard to the physical constitution of their compon¬ 
ent elements, all the virulent humours have characters more 
or less resembling those of the other pathological fluids, or 
even of the equivalent physiological humours. All, from the 
densest pulmonary nervous abscess to the clear transparent 
lymph of the vaccine vesicle or variolic pustule, are com¬ 
posed of a liquid and a solid portion , like the blood,—the pro¬ 
totype humour, and the source of all the others. 
The liquid portion is sometimes a plasma analogous to, or 
even identical with, that of the blood and lymph. Like it, 
the plasma of the virulent humours has for its base or funda¬ 
mental elements albumen and fibrogeneous matters, which 
coagulate spontaneously when removed from the organism 
and form fibrine. This coagulability is frequently found to 
be most marked in those humours which are engendered by 
lesions developed in the midst of the tissues; while the viru¬ 
lent humours, or mucus poured out on the surface of organs, 
are, on the contrary, generally destitute of this character, or at 
least do not readily show it. Most frequently, when we examine 
the fluid portion of virulent humours, the coagulant action 
has deprived it of the characters of a plasma; so that it is 
only exceptionally that this name can be applied to it. In 
general, the liquid element of the virulent humours shall be 
designated as the fluid or serous portion or serum. 
The solid portion comprises the elements held in suspension 
in the liquid part. These are more or less voluminous cells, 
white globules, molecular granules, and proto-organisms. 
They will be termed, in common, solid elements , corpuscular 
substances , corpuscles , and defi?iiteparticles, to distinguish them 
from the matters in solution which form the base of the plasma 
or serum. 
Is it in the substances in suspension or those in solution that 
the virulent property is fixed ? The answer to this question 
contains the determination of the physical condition of virus, 
and we will see that this response should be in favour of the 
substances in suspension. Three orders of facts will enable 
you to decide that the specific activity belongs to the solid 
elements of the virulent humours, and that the serum has no 
participation in this activity. 
1. In experimenting with the virulent humours, gradually 
and progressively diluted in an inert vehicle, their activity is 
manifested not as if it were uniformly distributed in the whole 
mass and belonged to all the molecules, but as if it were the 
exclusive attribute of some of these molecules dispersed here 
