858 ON THE REAL NATURE OF DISEASE GERMS. 
diffused through it, this by contraction after coagulation 
would filter off the little bioplasts, and leave a serum perfectly 
free. Dr. Farr calls the living particles biads (/3m, force, 
(3loq, life), and speaks of the vaccine particles as vaccinads .* 
These words are better than micro zy me, adopted by Mr. Simon 
and others, because they involve no theory save that the 
particles are living , while the latter term affirms them to be 
of the nature of a ferment acting like yeast. 
The circumstance that vaccine lymph retains its activity 
if kept in a tube for several weeks, seems conclusive as to 
the possibility of the particles retaining their vitality for a 
considerable time after they have been removed from the 
place where they grew ; the arguments advanced, as proving 
that the active power resides in the particles and not in the 
fluid, being admitted. It is not more difficult to explain the 
fact that such living particles may be dried without losing 
their power, than that an amoeba or rotifer should exhibit 
the same peculiarity. As this property is observed in con- 
nection with many of the lower forms of life, we might almost 
anticipate that the living matter from the highest organisms, 
if reduced to a degraded condition, would retain its vitality 
under circumstances which would cause its death in its 
normal condition. Yet it must not be supposed that these 
particles, any more than the “ dried animalcules,” are really 
dried. Some moisture is retained by the particles within the 
imperfectly-dried mass. Complete desiccation will destroy 
life in both cases. Since it has been showrn that the active 
powers of vaccine lymph reside in the minute particles of 
living germinal matter, and it has been proved that these 
may be dried (imperfectly) without loss of pow T er, it is surely 
not too much to conclude that the materies morbi of other and 
allied contagious disease is probably composed of living par- 
ticles, which have the same property of living for some time 
in a state of partial desiccation. 
Living Germs of Variola . — 1 have examined the contents of 
the little vesicle which rises in small-pox at different stages 
of its development, and find, as in allied pathological changes, 
vast multitudes of minute particles of living matter or bio- 
plasm, but, as will have been anticipated from wffiat has been 
already said, these present nothing peculiar or characteristic, 
nothing that would enable us to say if w 7 e saw these particles 
under the microscope that they were obtained from a small- 
pox vesicle, and would certainly give rise to that disease. I 
have made a drawing of some of the varioloid bioplasts from 
a well-developed vesicle on the fifth day of the disease, and 
also from a vesicle which was just making its appearance. 
# ‘ Report on the Cholera Epidemic of 1866/ p. lxx. 
