Massachusett's State Board
of Health for
year 1909.
158
TABLE XVII.
Average Bacterial Analyses of the Lawrence City Filter.
Per cent of samples con- taining B. Coli.
Bacteria per c.c.
Per cent of Bacteria removed.
40° C.
40° C.
20° C.
20° C.
Total.
Red.
Total.
Red.
lc.c. 100c.c.
Merrimack River-Intake of
7400
180
100
the Lawrence City Filter
100.0 100.0
Effluent from Lawrence)
60
7
3
City Filter (old Filter) .......{
99.2
96.1
97.0
8.6
50.7
Effluent from Lawrence
City Filter (new Filter)...
100
9
3
98.7
95.0
97.0 17.1
56.9
Mixed Effluents as pumped to Distributing Reservoir
Water from Outlet of the
Distributing Reservoir ...}
80
6
2
32
Water from a Tap at Law-}
32
en
5
1
9.4
57.4
4.2
55.7
Ι
0.0
42.5
II. REPORTS ON WATER SUPPLIES IN THE TROPICS.
Unfortunately it has proved very difficult to get any extended results from neigh- bouring places; the following are the chief facts obtained.
SHANGHAI.
=
Total average colonies in the filtered water grown on agar at 37° C. 15 per c.c. The unfiltered water is only occasionally tested and is stated to contain roughly 50,000 colonies per c.c. (N.B.-It is not stated if this figure is a gelatine or agar count.)
The filtered water has very little variation.
Bacillus Coli Communis is stated to be present as a rule in 0-3 c.c. of water and upwards.
The Health Officer does not consider the public filtered water supply satisfactory for drinking purposes unless further treated domestically by boiling or Berkefeld filtration,
The above facts were supplied by the Acting Secretary, The Council Room, Shanghai, in a letter to the Colonial Secretary, Hongkong, dated July 26th, 1910.
MANILA.
The following information regarding the water supply in Manila was received from the Bureau of Science of the Philippine Government and forwarded by H.B.M's Acting Consul General to the Officer Administering the Government in a letter dated 29th August, 1910-
"The unfiltered water of the City Water Supply of Manila generally contains in the neighbourhood of 350 Colonies per c.c. The number after filtration depends on the cleanliness and the method of filtering.