42 
HOUSEHOLD BACTERIOLOGY . 
Cold and 
Yeasts 
Experiment 
with Yeasts 
working by the yeast means no possible raising of the 
dough by the gas. Sometimes the dried yeast cake 
has been carelessly prepared in this respect and the 
yeast plants are nearly all dead. 
The yeast plants can endure cold better than heat. 
FIG. 24, YEAST PLANTS IN VARIOUS STAGES OF BUDDING OR 
REPRODUCTION. (After Sedgwick aud Wilson.) 
It hinders their work but does not quickly kill them. 
To show the favorable or unfavorable tempera¬ 
ture for the growth of yeast plants, take one-half 
cup each of boiling, lukewarm and ice-cold water. 
Add to each one tablespoonful of molasses and one- 
