191
SAMPLE V.—FOUNTAIN IN FRONT 0F OLD VETERINARY HOSPITAL.
C o l o n y n u m b e r .
Lact ose.
S a c c h a r o s e .
D u l c i t e .
A d o n i t e . I n u l i n .
V o g a s a n d P r o s k .
I n d o l .
M o t i l i t y .
G r o u p .
Bacillus.
Group and
remarks.
(a ) Total colonies per cc. on agar at 37º-260.
(b) Bile salt lactose, medium.
+
-
1 tube 20 cc. of water taken
..
. .
1
..
1 +
- - - - - + - I B. Vesiculosus
.. Group I, 5.
2 + + - - - - + - IV B. Coscoroba
..
„
II, nil.
2 tubes 10 cc.
..
..
2
..
3 + + - - - + - + IV B. Cloacæ..
..
„ III, nil.
3
5 cc.
. .
3
. .
4 + - - - - - + — I B. V esiculosus
...
„ 1V,, 5.
3
1 cc.
.. .. ..
2
1
5 + - - - - - + - I
Do.
3
• 1 cc.
.. ...
. .
3
6 + + - - - + - + IV B . C l o a c æ
3
• 01 cc.
..
..
. .
3 7 + + - - - - + + IV B. 106
..
.. Class I, nil.
(a) Fœcal bacilli in 1 cc. and upwards.
8 + + - - - + - - 1V B. 112
..
.. „ II, 2.
9 + - - - - - - - I B. Mutabilis ..
..
„ III, 7.
10 + - - - - - - - I
Do. ..
.. Undetermined 1.
REPORT.
C Considering how small has been the rainfall since the last analysis was carried out, it is not a little
surprising to find the susceptible germs of Class I, in the water of the Samalkota Canal. These germs may have
been derived from a fairly distant source where the rainfall has been heavier, but it seems more probable that
their presence in the water is due to some local and temporary cause coinciding with the time samples were
taken. It will be remembered that in February last and after a similar spell of dry weather. germs of this type
were found in the sub-soil water where the new filter bed was being excavated. The results got from Sample II
show very clearly the advantage of storage. A fivefold decrease of the fœcal bacilli, and a reduction of one half
of the others has resulted. We have here again an illustration of the selective action of the natural purifying
agencies. The results of filtration are entirely bad. As compared with the storage water fœcal bacilli are
multiplied fivefold, and a huge total of other germs has been added. This must be due to a foul condition of the
post filtration passages, which has often been noted in association with a water containing, as will in this instance
be noted later, a considerable amount of organic matter. Further support is given to the conclusion that the
pipes, etc., are foul by the condition of the water drawn from a pillar fountain near the Port Railway Station.
In this sample there are one hundred times as many fœcal germs and twenty-five times as many of other kinds
as in the original raw water, and compared with the stored water it is correspondingly worse. A farther feature
in this sample and the next drawn from the fountain in front of the old Veterinary Hospital which requires
notice is the large number of varieties of fœcal germs present. This suggests that surface contamination may be
getting into the water owing to imperfections in the pipe lines. The pipes should be cleaned out, and examined
for leaks.
Chemically the figures for albuminoid nitrogen and absorbed oxygen are too high, and the ratio between
the figures indicates that at least some of the organic matter is of animal origin. The presence of this organic
matter in the water seems to be favourable to the growth of micro-organisms which explains the very high totals
seen in the filtered water. Some purification has gone on during the passage of the water through the filters and
pipes as shown by the decreased albuminoid nitrogen and absorbed oxygen, and a corresponding increase in the
oxidised nitrogen.