MATERIAL FOR EXAMINATION IN DISEASE. 924] 
able of the culture media to the bedside or autopsy table. 
Such a list of media, if fairly complete, would comprise 
nutrient bouillon alone and mixed with one-third its 
quantity of ascitic fluid, slanted nutrient agar, and 
firmly solidified slanted blood-serum. If only one 
variety of media is to be used the solidified blood- - 
serum is most useful for parasitic bacteria, and this can 
be easily carried by the physician and inoculated by 
him, even if he is not very familiar with bacterio- 
logical technique. The material must be obtained in 
different ways, according to the nature of the infection. 
For the detection of the bacteria causing septicaemia 
we are met with the difficulty that there are apt to be 
very few or no organisms present in the blood until 
shortly before death. It will, therefore, be useless to 
take only a drop of blood for cultures, as even when 
present there may not be more than eight or ten organ- 
isms in a cubic centimetre. If cultures are to be made 
at all, it is, therefore, best to make them correctly by 
taking from 3 to 5 c.c. of blood by means of a sterile 
hypodermatic needle, or a suitable glass tube armed 
with a hypodermatic needle, from the vein of the arm, 
after proper cleansing of the skin and a tiny incision. 
Into each of five different tubes containing bouillon we 
add one-fifth of the quantity of blood withdrawn. We 
have made by this mixture of blood and bouillon a most 
suitable medium for the growth of all bacteria which 
produce septicemia, and at the same time have added a 
sufficient quantity of blood to insure us the best possible 
chance of having added some of the bacteria producing 
the disease. We also streak several nutrient agar plates 
with blood, so as to indicate roughly the number of 
organisms present, if they happen to be in abundance. 
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