BACTERIA SIN DH DATRY: Ig 
large in such a way that they, too, could obtain an advantage 
from it. For these reasons, in spite of my hesitation, it was 
finally decided to introduce the culture to butter-makers as 
widely as possible for the purpose of further testing its powers. 
THE USE OF PURE CULTURES OF BACTERIA IN DAIRYING. 
It may be well here to state in a word to what extent the use 
of pure cultures of bacteria is new to dairying and to science. 
Pure cultures for cream ripening have been employed before to 
some extent. ‘The method was first adopted in Denmark by 
Prof. Storch, and was followed later in Germany and to a less 
extent in other countries. Several different pure cultures 
(2. e., cultures of different species of bacteria) have been dis- 
tributed and used for this purpose. In Denmark their use has 
become very common. A _ year ago their use was hardly 
known in the United States, although, at least, one pure cul- 
ture was on the market. ‘Thus the use of pure cultures is not 
new, although the species which has come to be known as 
Bacillus No. 41 is new to dairying, and more than this, its use 
involves a new principle. All such cultures hitherto used 
have been lactic organisms, which change milk-sugar to lactic 
acid and their use rapidly sours the cream. ‘They cannot, 
therefore, be used to much advantage in cream already filled 
with bacteria, and to get the best results it is necessary to 
pasteurize the cream. Bacillus No. 41 is not properly a lactic 
organism. While it does produce a very little acid it never 
curdles milk or cream, but on the contrary it checks rather 
than hastens souring. It produces flavor without much acid. 
It can, therefore, be used in ordinary cream without pas- 
teurizing. The use of lactic organisms is, then, not new, 
but the use of a bacterium in ordinary cream to produce 
flavor alone, depending upon the species already present to give 
sufficient acid, is new. ‘To this extent, therefore, the use 
of Bacillus No. 41 involves a new principle. This difference 
is one of no little importance, since it makes great difference 
in the adaptability of the organism to our present methods of 
dairying. ‘That the future may see a wide extension of the 
practice of pasteurizing cream before ripening is very probable, 
and in my opinion desirable. But that time has not yet come, 
and in order that a pure culture may be introduced into the 
