SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 9 
Springs house. The bacterial count at this poimt is between 
600 and 100 colonies to the ecu. em. 
Various tests of the city water made from the faucets in 
different parts of the city shows an average of about 30 colonies 
to le.c. The difference in the count is caused by the lack of 
nutrition and oxygen, and the pressure to which the water is 
subjected in the pipes. 
It is commonly taught that any water supply containing 
over 500 colonies to 1 ¢. c. is unfit for use. You ean see, 
however, that Los Angeles faucet water is comparatively free 
from bacteria. <A bacterial examination of distilled water 
as delivered shows 190 colonies to 1 ¢. ¢., but of course weighing 
a matter of this kind, one must remember the kind of bacteria 
present is the all important consideration. It is a possibility 
of course that the organisms in city water are more apt to 
be pathogenic on account of the pollution of the San Fer- 
nando valley farmers and their stock, but in discussing the 
question of the transmission of typhoid fever through our 
water supply with Dr. Powers recently, he said in the history 
of the Health department he has never had reason to believe 
any epidemic of typhoid fever had its origin in the water 
supplied to the city, but rather from overflowing cesspools, 
eases of the disease at dairies, and the difficulty of proper 
sewage disposal at the beaches. About three-fourths of the 
cases of typhoid fever reported in Los Angeles have their origin 
in the country. 
In making bacterial tests of water, certain general principles 
should be borne in mind. In the first place, the plating of the 
water should be done at the well, reservoir or stream to be test- 
ed. If samples are to be transported to the laboratory they 
should be placed on ice. Several plates should be made from 
portions of 1 ¢.c. 1-10, 410 and 6-10 gives one a good control 
test. In routine work agar is preferred to gelatine culture me- 
dia, so that the growth may take place at a temperature above 
that of the room, 30 to 87448 C. The isolation of specific organ- 
isms from a given sample of water presents many difficulties. 
B. Typhosus has been isolated from water about once im 
500,000 times according to Williams. B. Coli is more readily 
found on account of its greater endurance, and although this 
organism has been found in the faeces of birds and other 
animals besides man its presence in large numbers in a given 
sample of water is considered suspicious by many city bacter- 
iologists. 
The Owens river project. opens up a bright future for 
Southern California. You are all more or less familiar with 
the plan to bring the waters of this fertile valley 200 miles 
northeast in Inyo County to Los Angeles. <A elear and inter- 
