CHEMICAL EXAMINATION OF THE WATER SUPPLY. 299 
Year 
Sanitary improvements, remarks, etc. 
Cases. 
ending — 
Attendants. 
Patients. 
June 30,1905 
Pasteurizing apparatus purchased last year in- 
stalled and in daily use for whole milk supply 
since November, 1904. No typhoid cases in 
hospital except two cases which developed in 
attendants a short time after their employ- 
ment. Inoculation from external source. 
2 cases. 
Jime 30, 1906 
Contract to bore two more wells; work in prog- 
ress at present time. Five cases of typhoid 
among attendants; all traced to same source — 
the use of infected ice cream purchased at a 
small store outside of hospital. Cases syn- 
chronous; wife and two children of storekeeper 
had typhoid at time of infection. No ty- 
phoid among inmates. 
5 cases; 1 death. 
AVe also note that this institution is somewhat isolated, and thus 
removed from the influence of flies and other factors which operate 
in the more complex conditions in the city. Further, the new build- 
ings were occupied September to December, 1904, thus relieving 
the overcrowded condition of the old buildings. 
soldiers’ home. 
This institution, while supplied with city water, uses its own supply 
exclusively for drinking purposes. This supply comes mainly from 
a well 150 feet in depth, in addition to which there are several other 
wells and springs scattered over the grounds, from which the inmates 
occasionally drink while taking exercise about the grounds. 
Frequent examinations of these waters have been made by Doctor 
Carroll at the laboratory of the War Department, with the result that 
some of the wells at this institution have been closed from time to 
time. Those now open gave good results on analysis. The water 
now supplied the institution from the main well has been analyzed 
both at the Hygienic Laboratory and at the laboratory of the filtra- 
tion plant. The results of these analyses are given in Table 27. It 
will be seen that the water is low in total solids, chlorine, free and 
albuminoid ammonia, and nitrites. It contains a larger quantity of 
nitrates than we might expect from the depth and location of the 
well. The bacteriological examination showed no pollution, so that 
we have every reason to regard this also as a pure and wholesome 
water. This institution was found also to be free from typhoid fever. 
CHEVY CHASE. 
This community is supplied with water from 5 artesian wells, vary- 
ing in depth from 100 to 120 feet. These wells are some distance 
apart, but all of them are located in the neighborhood of Chevy Chase 
circle. Each well is incased in a 4-inch iron pipe, through which the 
water is pumped into a steel standpipe, flowdng by gravity from the 
standpipe to the taps. The delivery mains of two of the wells do not 
