VOLATILE ANTISEPTICS AND SOIL ORGANISMS. 155 
with the exception that only one was treated with chloro- 
form. The soil in four plats was sterilized in autoclav 
(tests showing sterilization to be complete). Four were 
filled with soil partially sterilized, 7. e., heated to a tempera- 
ture of 90°—100° C. in autoclav without pressure. The 
chemicals were added in three holes at equal distances 
apart and in three strengths: 22.5 cc. approximating 7 ce. 
per square foot or a weak practical application, however, 
one with which other experimenters have obtained marked 
increases in yield; 62 cc. or approximately .2% of dry 
weight of soil; and 310 cc. or approximately 1.% dry weight 
of soil. After allowing the chemicals to act for four days, the 
plats were thoroughly stirred; twelve were seeded to oats and 
thirteen to buckwheat. Duplicate plats were separated as 
far as possible. 
Three samples were taken from the whole depth of dupli- 
cate plats by means of sterile tin cylinders. These samples 
were then thoroughly mixed and analyses made as pre- 
viously given. Table V gives the bacterial count at inter- 
vals, from beginning until just before harvest, also the 
relative yield of duplicates, both in total dry weight and 
seed. There were some slight variations in the water con- 
tent at times, but this was not sufficient, in any of the plats 
treated, to cause a difference in bacterial content. 
From this experiment, typical of others and selected be- 
cause of the more marked increase in yield and wider varia- 
tion in treatment, but one conclusion can be drawn: That 
with this soil no increase in bacterial content was evident 
with the wide variation in applications, but, at the same time, 
a marked increase in yield was obtained. 
With heat, the results were different. There was an 
enormous increase in number of bacteria, not, however, 
necessarily concomitant with an increase in yield. In the 
case of this soil, there were evidently toxic substances pro- 
duced in the process of heating, for most of the young oat 
plants died as a result, and those that did not, made no 
growth for several weeks. With buckwheat, the plants were 
unable to overcome this detrimental effect in time to show 
