of Bacteria and their Allies by Heterogenesis. 401 
death, with every precaution needful to prevent contamina- 
tion from without, swarms of microorganisms can be made to 
appear therein at will. 
Speaking of such experiments made by himself, Burdon 
Sanderson wrote as follows*:— Under the conditions I 
have described to you, it seems to me quite impossible to 
suppose either that germs could penetrate to the organ from 
the outside or that any germ encountered by the organ in 
its transference from the body of the animal to the basin 
could escape destruction. If, therefore, Bacteria be found, 
they or their germs must have been there before the organ 
was plunged into the hot liquid.... The results of all the 
experiments, whether with liver or kidneys, was the same. 
The soft red kernel of uncooked tissue at the middle of the 
organ always contained Bacteria, the vigorous development 
of which was indicated by their large size, countless num- 
bers, and active movements. ‘To my mind the experiment 
is conclusive.” 
In reference to this it is right to say that similar results 
have been obtained by other investigators using either 
similar methods or methods equally trustworthy. Such 
experiments have been made by Tiegel, Billroth, Nencki 
and Giacosa, Horsley and Mott, as well as by myself. 
As I have previously intimated, the finding of organisms 
under these conditions is a fact so important in view of the 
theories of Pasteur and Lister, and the general belief as to 
the germicidal qualities of the blood, that the results require 
to be most carefully scrutinized. 
To postulate the presence of “latent germs”’ in these 
abdominal organs and to assign as a reason the close 
“ proximity to absorbing mucous membranes,” and nothing 
else, surely cannot be regarded as a full and satisfactory 
explanation. It assumes, without proof of any kind, that 
microorganisms, even in healthy animals, are constantly 
making their way out through the walls of the intestine, 
and wandering promiscuously into this or that organ, only 
in the end to lapse into a condition of “ latent vitality.” 
Could anything in the way of explanation be more gratuitous 
and unsatistactory ? 
With a view to throwing light upon this important question 
by the production of actual evidence I obtained a sheep’s 
kidney from a recently killed animal, and saw a coating of 
fat nearly an inch thick stripped from it. The whole organ 
was then left to soak for four hours in a two per cent. 
* Brit. Med, Journ, 1878, vol. i. p. 119. 
