DEVELOPMENT OF THE BACTERIA. 109 
Two kinds of researches have been undertaken 
for the purpose of discovering germs in normal 
blood. ‘The direct method, or microscopic exam- 
ination, has given results very much disputed. 
The blood contains, indeed, a considerable number 
of little granules, of which the nature is doubtful, 
and which it is difficult to distinguish from MJicro- 
coccus. Thus, while Liiders asserts that normal 
blood contains germs, or spores, which only await 
a favorable alteration in the fluid in order to de- 
velop themselves, Rindfleisch formally denies their 
existence. 
The indirect method, which consists in cultivat- 
in culture cells in which blood, in a moist state was kept under daily 
observation for a week or more. 
“The method employed seemed the only one practicable for obtaining 
blood from a large number of individuals without inflicting unwarrant- 
able pain and disturbance upon the sick. It was as follows: One of the 
patient’s fingers was carefully washed with a wet towel (wet sometimes 
with alcohol and at others with water), and a puncture was made just 
back of the matrix of the nail with a small triangular-pointed trovar 
from hypodermic syringe case. As quickly as possible a number of thin 
glass covers were applied to the drop of blood which flowed. And these 
were then inverted over shallow cells in clean glass slips, being attached 
usually by a circle of white zinc cement. In dry preparations, which 
are most suitable for photography, the small drop of blood was spread 
upon the thin glass cover by means of the end of a glass slip. 
“The thin glass covers were taken from a bottle of alcohol, and 
cleaned immediately before using; and usually the glass slips were 
heated shortly before applying the covers, for the purpose of destroying 
any atmospheric germs which might have lodged upon them. These 
precautions were not, however, sufficient to prevent the inoculation of 
certain specimens by germs floating in the atmosphere (Penicillium and 
micrococci) ; and in nearly every specimen the presence of epithelial cells, 
and occasionally a fibre of cotton or linen, gave evidence that under the 
circumstances such contamination was unavoidable. It is therefore be- 
lieved that any organism developing in the blood of yellow-fever, or 
of other diseases collected by the method described, or by any similar 
method, can have no great significance, unless it is found to develop as 
a rule (not occasionally) in the blood of patients suffering from the dis- 
