1322 Wisconsin Academy of Sciences, Arts, ayid Letters. 
The method of preparation followed was that suggested by 
Kendall and Day.t Later, media made as above was neutralized 
biologically as suggested by Kinyoun and Dei ter.* * This method 
led to somewhat more satisfactory results due, it would seem, to 
the use of phenolthalein rather than litmus as an indicator, and 
consequently a more definite point of alkalinity. It seems, how¬ 
ever, unnecessary to neutralize biologically each batch of medium 
as suggested by Kinyoun and Deiter, but when the proper reac¬ 
tion has been determined this point can be satisfactorily secured 
by the ordinary methods of titration. It would seem possible 
also to modify this medium and its method of use so that it 
would be both easily handled and extremely useful. 
Fig. 8. Thermal Death-point Tubes. 
D. Thermal Death Point op Bacillus Coli. 
1. New Method of Testing. Although the thermal death point 
of B. coli has been frequently determined, it seemed desirable to 
test the particular strains used here and to do it quantitatively. 
The method used is a modification and improvement on a 
method previously used by the writer. In its present form 
it is somewhat like the method suggested by Sternberg, except 
that by the use of the mechanical volumetric pipette, previously 
described, it is possible to take up measured quantities. 
t Jour. Med. Research, 1911, 25, p. 95. 
* Loc. cit. 
