226 
water at McKeesport ranges from 20 parts per 
million alkaline during high stage of water to 
39 parts acid at low stage, and the bacterial life 
of the stream is directly affected thereby. 
The monthly averages of bacteria per cubic 
centimeter, acidity and height of river, are given 
below for the year 1910: 
Stage 
AV. No. Bacteria of 
Month Acidity per ¢c.c. River 
1910 (a) (b) (c) 
January ..... 11 31,000 5.3 
February .... 37 20,000 3.4 
Manchwrernirrrs 36 21,000 3.1 
AN oval) Sb aoa 52 12,000 Sie 
IMiasyans vercyerstsicis 23 2,000 1.6 
dwn) Son eanes 6 6,500 3.3 
Uw dese pod 65 205 0.7 
INUAVTG o50660 182 9 0.1 
September ... 113 97 — 0.2 
Octobersee-ee 240 240 —0.1 
November .... 176 160 0.1 
December .... 29 2,400 2.0 
(a) Acidity to methyl orange in parts per mil- 
lion. 
(0) 48 hours’ incubation at 20° C. 
(c) Gauge height in feet at West Newton. 
It can be stated in a general way that the bac- 
terial numbers vary with the gauge height of the 
river and inversely as the acidity. The acidity of 
the water is controlled by the conditions of rain- 
fall, run off and flow, inasmuch as these are the 
factors which affect the dilution of the mine drain- 
age. Allowing for the natural fluctuation of bac- 
terial life in a flowing stream, the presence of the 
mine water is responsible for a considerable reduc- 
tion at all times except during floods, when the 
water is alkaline, while during high acidity the 
effect approaches sterilization. 
Water Sterilization by Emergency Chlorinated 
Lime Treatment Plants: RALPH E. IRWIN. 
When emergencies call for the immediate steril- 
ization of a public domestic water supply, tem- | 
porary treatment apparatus may be constructed 
by using barrels to mix and feed chlorinated lime 
into the suction main, suction well or point where 
the water passes and thorough mixing is insured. 
The solution may be mixed and settled in one 
barrel and fed from another via regulating valves. 
With this crude device water from large and small 
streams, wells and springs have been disinfected 
aud communities protected from water-borne 
disease. 
SCIENCE 
[N.S. Vou. XXXV. No. 893: 
Two examples are given showing the bacteriolog- 
ical results obtained by treating similar spring 
waters that were infected and had caused epi- 
demics of a water-borne disease. 
The first spring furnished 1 to 1.5 million gal- 
lons daily and was under municipal control where 
political protection was given inefficient employees. 
During a period of 115 days, bacteriological de- 
terminations were made showing the total number 
of bacteria and B. coli present in 85 samples of 
untreated water from the spring, 70 samples of 
treated water as it left the pump and 75 samples 
from taps about the city. On 8 days samples 
were obtained showing B. coli in such large num- 
bers that it was evident little, if any, lime was 
being added. The results as a whole show, how- 
ever, that the prescribed 6 to 8 pounds of high- 
grade chlorinated lime per million gallons was 
sufficient to sterilize the water if added as directed. 
The second spring furnished 3 to 3.5 million 
gallons daily and was under strict corporate con- 
trol with employees obeying orders. During a 
period of 103 days, bacteriological determinations 
were made showing the total number of bacteria 
and B. coli present in 36 samples of untreated 
water from the spring and 36 samples of treated 
water from taps on the pump or distributing sys- 
tem. The treated water showed excellent reduc- 
tions in total counts in every instance, and B. colt 
were absent throughout the period of treatment. 
With a erude device such as described in the 
hands of efficient workmen during emergencies, 
creditable results may be obtained and valuable 
protection given. 
The Distribution of Bacteria in Certain New 
York Soils: H. J. Conn. 
Extensive work for two years with a certain clay 
loam at Ithaca has resulted in the isolation and 
study of about five hundred cultures. These cul- 
tures have been classified into thirty-four types, 
which are essentially species. Grouping these 
types into six easily distinguished classes, their 
relative frequency can be thus stated: 
5-10 per cent. spore-producing liquefiers; large 
rods (é. g., B. subtilis and B. mycoides). 
5-10 per cent. non-spore-producing, rapid lique- 
fiers; small rods with polar flagella (e. g., Ps. 
fluorescens). 
40-70 per cent. non-spore-producing, slow lique- 
fiers; short rods, immotile (except one with polar 
flagella) ; growing very poorly in ordinary labo- 
ratory media. 
