1362 Wisconsin Academy of Sciences, Arts, and Letters. 
V. SUMMARY AND CONCLUSIONS. 
A collecting case for carrying milk samples of 120 c. c. capacity 
is described. 
A study of the loss of volume during sterilization in the auto¬ 
clave reveals the fact that in the case of water blanks the loss 
varies from 1 to 8 per cent; that the loss varies with the auto¬ 
clave ; that the loss can be prevented by closing the autoclave up 
cold and not permitting the escape of steam, and that the insuf¬ 
ficiency of sterilization in this way can be avoided by running 
the material to be sterilized a second time. The use of caps of 
paraffined paper is suggested on water blanks to prevent evapo¬ 
ration. In making dilutions and shaking them it is recommended 
that the sterile paper cap be placed over the neck of the bottle 
and forced in place with a cork which is suggested for use in¬ 
stead of the usual cotton plug. 
A study of pipettes leads to certain suggestions in regard to 
form and methods of cleaning. 
A new piece of apparatus is described to be known as the “Me¬ 
chanical volumetric pipette” or “pipettometer.” This makes 
the accurate measurement of fractions of a cubic centimeter, with 
an ungraduated pipette, easily possible. It possesses other ad¬ 
vantages over the ordinary pipette used in bacteriological wo*rk. 
It will also be found useful in graduating pipettes. 
A study of Schroeder’s ring method shows it to be considerably 
less accurate than the ordinary methods, and on this account 
unworthy of general adoption. 
Reasons for the use of an incubation temperature of 21° C. in¬ 
stead of 37° C. are suggested. 
A new form of apparatus for counting colonies is described. 
. In tests for B. coli in milk a new medium (neutral red milk 
broth) is described; a comparison of the Smith and Durham fer¬ 
mentation tubes is made, and a simple form of gasometer for the 
latter is suggested. 
Endo’s medium is discussed as a means of detecting B. coli in 
milk as well as certain phases of its manufacture. 
A new method of determining the thermal death-point of bac- 
