856 ON THE REAL NATURE OF DISEASE GERMS. 
was produced has occurred ; living matter which has descended 
directly from the living matter of health, but which has acquired 
the property of retaining its life under new conditions; living 
matter destroyed with difficulty, and possessing such won- 
derful energy that it will grow and multiply when removed 
from the seat of its development and transferred to another 
situation, provided only it be supplied with suitable nutrient 
pabulum — and it is to be feared the ordinary nutrient fluids 
of a perfectly healthy organism are eminently adapted for the 
nutrition of this destructive virus. 
The Pus of Purulent Ophthalmia — Gonorrhoeal Pus. — Such 
is the vitality of these forms of bioplasm that they will grow 
and multiply upon certain mucous surfaces if placed there; 
not only so, but the living particles will retain their vitality 
for some time after their removal from the surface upon 
which they grew. They may even be transported long 
distances by the air, or they may remain for some time in 
moist cloths without being destroyed. When once a room 
has been infected with such particles, some weeks may elapse 
before the death of all the specific disease-carrying germs 
has taken place. 
The pus possessing specific contagious properties cannot 
be distinguished from ordinary pus. It differs indeed from 
this last, but not in appearance, chemical composition, or 
physical properties. It differs in vital power. 
Vaccine Lymph. — Vaccine lymph which has been just re- 
moved from the growing vesicle will be found to contain a 
great number of extremely minute particles of bioplasm, 
which may be well seen under a power magnifying from 1000 
to 2000 diameters. In 1863 I made a drawing of the appear- 
ances I observed in the bioplasts from a drop of perfectly 
fresh lymph which had been transferred to a warm glass 
slide, and carefully covered w r ith very thin glass, under the 
-a^th object-glass, which magnifies about 1800 diameters. 
The results are represented in the plate accompanying a 
memoir which w T as published in the 4 Quarterly Journal of 
Microscopical Science * for April, 1864. 
In vaccine lymph which has been kept for some time in 
glass tubes multitudes of very minute particles are observed,, 
and these exhibit the most active molecular movements. 
These particles have often been termed debris , and have been 
regarded as quite unimportant elements of the lymph. To 
them, however, the active properties of the lymph are entirely 
and solely due. And I should be no more inclined, in the 
absence of the most positive evidence to the contrary, to 
regard the fluid portion of the vaccine lymph as the active 
