232 
The Bacteriological Improvement of a Milk Sup- 
ply by other than Laboratory Means: H. A. 
HARDING. 
Bacterial studies have shown that the essentials 
for the production of cleaner milk are: 
1. The utensils and the cow and her surround- 
ings during the milking process must be as clean 
as possible. 
2. The milk must be cooled as promptly and as 
thoroughly as possible. The problem of the bac- 
teriologists becomes: how to induce the production 
of milk in accord with these essentials. 
Attempts at securing this by establishing maxi- 
mum permissible germ contents are undesirable 
because: 
1. We lack data for establishing the point at 
which germ content begins to menace the public 
health. 
2. We lack technique for determining the germ 
content of milk with an accuracy demanded by 
such legal enactment. 
3. Such enactment has slight educational value 
because it can not be readily translated by dairy- 
men into terms of their dairy practises. 
The bacteriologists must translate the results 
of their studies into terms of dairy practises, and 
this translation may well take the form of a score 
card. If the valuation in this score card is correct 
the resulting score is an accurate measure of the 
relative desirability of the dairy product. 
Such a mathematical expression is valuable be- 
cause it facilitates buying and selling milk on the 
basis of quality. 
In Geneva, N. Y., where the Cornell score card 
was taken voluntarily by the milkmen as a basis 
of payment according to quality: 
“¢Poor’’ milk, originally one third of the total 
supply, decreased sharply and disappeared after 
three years. 
‘¢Medium’’ milk, originally about two thirds of 
the supply, decreased sharply and disappeared 
after three years. 
‘¢Good’’ milk, originally only five per cent. of 
the supply, quickly displaced the two lower grades. 
SCIENCE 
[N.S. Von. XX XV. No. 893 
“¢Fixcellent’’ milk, previously unknown, was 
twelve per cent. of the supply after three years. 
The details of this work are given in New York 
Agricultural Experiment Station Bulletin 337. 
This complete transformation of a municipal 
milk supply was accomplished at a cost to the 
city of $500 per year. 
The dairymen are desirous of furnishing the 
highest grade of milk for which they can get a 
price proportionate to the quality. The first neces- 
sity is a definition of the desired quality in terms 
which the dairymen can clearly understand. The 
dairy score card is the most promising attempt in 
this direction. The second necessity is the estab- 
lishing of definite market grades of quality in 
milk, so that the consumer can purchase intelli- 
gently and create a commercial demand for a 
better article. The action of the New York Health 
Department in this direction is commendable. 
Any permanent improvement in a municipal 
milk supply must rest upon conditions which make 
it more profitable to furnish a cleaner milk than 
to furnish a dirtier one. 
The Principle of Vacuum Cleaning as Applied to 
Dairy Cows: G. Li. RUEHLE. 
The Object—A comparison of the results ob- 
tained by a vacuum cleaner and by hand cleaning 
of cows. The points considered were (1) the 
effect on the germ content of the milk, (2) the 
time consumed. 
The Methodi—Two cows were cleaned each 
night by each method. The groups were alter- 
nated on succeeding nights. Observations were 
made on 22 nights. 
The general average for hand cleaning was 669 
per ¢.c., and for machine cleaning it was 1,145 
per ¢.¢. 
Time Consumed.—Owing to the small number of 
cows per day, measurements of the time required 
by each method were not satisfactory. However, it 
was plain that the vacuum cleaning consumed 
more time than hand cleaning. As vacuum clean- 
ing of cows took more time and gave poorer re- 
sults, it does not commend itself to dairy practise. 
EFFECT ON GERM CONTENT 
Germ Content perc.c. from Machine and Hand Cleaned Cows 
Cow No.1 Cow No. 2 Cow No. 3 Cow No. 4 
Hand Machine - Hand Machine Hand Machine Hand Machine 
No. samples. 10 12 10 12 11 11 11 11 
Totals.........-. 20,765 | 26,459 | 1,479 | 1,624 ; 2,541 | 16,309 | 3,305 | 8,297 
Averages 2,077 2,205 148 35 231 1,483 300 754 
