146 
BOTANICAL GAZETTE [AUGUST 
by the rays only during the times when they were in very 
close proximity to the discharge tube. 
Soy p— 
Fic. 1 
In order to test the efficiency of 
BILLON-DAGUERRE’S method, a sterilizer 
similar to the one which he described 
was constructed by the writer, and dis- 
tilled water, contaminated with various 
bacteria, was passed through it. 
Although the water passed through at 
a much, slower rate than the one given 
by BrLtton-DAGUERRE, the water was 
. not sterilized. Another sterilizer was 
then constructed in which the organ- 
isms could receive a much longer ex- 
posure; the discharge tube was longer, 
the volume of liquid exposed at any 
one time was much less, and the chance 
of the bacteria coming in close contact 
with the discharge tube was much 
greater, as the liquid was caused to 
circulate around the discharge tube. 
The construction of the improved ster- 
ilizer is shown in fig.1. A glass tube A 
with bulbs on each end, into which ~ 
electrodes F were sealed, had side tubes 
as shown at B and C. The electrodes 
were of aluminum. The tube B served 
as the inlet and C as the outlet for the 
liquid under treatment. Within the 
glass tube there was a very thin-walled 
tube of quartz (D). The distance be- 
tween the outside of the quartz tube 
and the inside of the glass tube was 
0.3mm. The quartz tube was sealed 
to the glass tube at E, E with 
DeKotinski cement, so that the space between the two tubes was 
not in communication with the remainder of the interior of the 
