344 ON THE NATURE OF FERMENTATION 
taneous generation, and prone to produce these and other fermentations, but 
which, by the act of boiling, we deprive of this tendency. Therefore, with 
a view to meeting this objection, the first part of my investigation was devoted 
to endeavouring to see whether or not milk, as it comes from the cow, really 
does or does not contain materials tending to the development of organisms or 
to fermentation of any kind. 
An exceedingly simple experiment will probably serve to convince you to 
a considerable extent with regard to this matter. If you go to a dairy where 
there is also a cow-house, take a couple of clean bottles, and fill one with milk 
from a pan in the dairy and the other with milk direct from the cow in the cow- 
house, the milk obtained from the dairy will be certain to sour, but that which 
you get direct from the cow will very probably never sour at all. It will prob- 
ably acquire a nasty bitter taste, and will not contain the Bacterium lactis or 
the Ordium lactis, but some other kinds of fungi. That very simple experiment 
is enough to show that the lactic-acid fermentation is not a change to which 
unboiled milk is spontaneously prone. And it occurred to me that, if all organ- 
isms and fermentations which occur in milk really depended on accidental 
introduction from without, by performing the experiment with a number of 
purified glasses and taking the milk in small quantities into each, we might by 
thus subdividing elude the foreign element and get the milk, in some of the glasses 
at least, not only without the lactic-acid fermentation or the Bacterium lactis, 
but without any fermentation or any bacterium, or any sort of organism. 
Accordingly, I prepared little glasses like these ; little test-tubes with test-tube 
caps, arranged upon a stand made of pieces of glass tube and silver wire. The 
stand containing the test-tubes was placed under a glass shade on a plate of 
glass and purified by exposure to 300° Fahr. in the hot box. Miulk having been 
received from the cow into a purified vessel, some of the milk was then, by 
means of a syringe attached to this pipette (the pipette having been also pre- 
viously purified), drawn up into the pipette, and then, by means of the syringe, 
each little cap being in succession raised, a few minims of milk were introduced 
into each of the glasses, the caps being immediately reapplied. The result was, 
every one of the milks underwent fermentation, and every one of them con- 
tained organisms, some of them as many as three different species. The great 
majority of those twelve glasses presented little orange specks, such as were 
never seen, I suppose, in any milk before ; and, on examining these, I found 
them to be little organisms belonging to a group to which I have ventured to 
give the name Granuligera, because they consist of granules, different from 
bacteria in this respect, that you might suppose them not to be organisms at 
all till you had the opportunity of seeing them undergoing multiplication by 
