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Sample (a) was taken from the trench filled in May 1908. The whole of the
trenching ground was more or less under water during part of June and again for many
days in October. The trench was opened at the end of November 1908. The night-
soil was found to be in a black sticky mass not unlike tar. It had an odour of manure,
but did not suggest fresh fœces. The analysis showed that the organisms that
were preponderating were bacillus grunthal 11 and bacillus cloacæ 1. Sporogenes
enteritidis were also present.
Sample (b) was taken from the sides of the trench at a depth of about
12 inches. A new trench has just been cut, so that the sample taken had not been exposed
to the sun. As already stated, this land has been trenched on for a period of ten years.
So the whole of it is highly contaminated. The organisms found were bacillus
grunthal 10 and bacillus cloacæ 2. Sporogenes enteritidis were absent.
Sample (c) was taken from the same trench but only 4 inches below the
surface of the ground. In this case three organisms were isolated, bacillus grunthal
4, bacillus cloacæ 5, and No. 73 in MacConkey's list 3.
Sample (5) Vizianagram trenching ground.—The trenching ground consists
of a gravelly soil situated on bare rock. The soil itself is very shallow, and is unsuit-
able both for trenching ground and for cultivation.
Sampie (a) was taken from a piece of ground that was trenched some time in
1907. The material was removed in April of 1908, the land was then ploughed and
levelled, and a crop of millet was raised on it. This was reaped in September
1908. The sample was taken towards the end of November 1908 from a depth of 4
inches below the surface. The only lactose fermenter that could be isolated from a gram
of this earth was bacillus No. 73. Sporogenes enteritidis spores were also found.
There was no great likelihood of this land being polluted by other means than by
trenching of night-soil, as it was far removed from habitations, but this cannot be
absolutely excluded.
Sample (b).—A trench was filled in with night-soil in April 1908. Water
stood on the trench during the rains, which occurred in July and August. The
trench was opened towards the end of November 1908. The night-soil was found to
be in much the same condition as that described in the Nellore trench, namely, to
somewhat resembling tar. It had a very bad, though not a very fœcal, odour. The
organisms that were isolated from this were, 9 colonies of bacillus grunthal, 2 of
coscoroba and 1. of bacillus cloacæ. Sporogenes enteritidis was also found to be
present.
Sampie (c).—A trench was filled in with night-soil in December 1907, emptied
in March 1908, and stood empty through rains till the end of November 1908. The
sample of earth was taken from the base of this trench, the portion that had been
exposed to the sun being removed to a depth of about 4 inches. The only lactose
fermenting organism that was isolated was bacillus grunthal. Sporogenes enteritidis
was also found.
Sample (6) Cocanada trenching ground.—The sample obtained from this
trenching ground are of a great importance and of considerable interest. The trenching
ground in Cocanada is situated in what is practically sea sand. The people in the
neighbourhood, not approving of the use of manure derived from human fœces, do not
utilize this material for fertilising their fields. The consequence is, trenches, that
are known to be at least six years old, exist in the ground. The Overseer and the
Municipal Secretary have lived in the town f or a large number of years, and have been
in the same position during this period, so that we consider the dates for filling the
trenches given by them, may be accepted as correct. The fact that no part of the
ground has ever been trenched twice over also renders it possible to give, with a fair
amount of accuracy, the dates when a certain plot was last trenched.
Sample (a) taken from a trench that was filled in six years ago. On cutting
into the trench, the black peaty layer was at once visible in the land. This plot of
ground had been ploughed up, and a crop of castor-oil had been grown on the ground.
But, as is usual with the cultivators in the east, deep ploughing and thorough mixing
of the soil is never resorted to. The surface is simply scratched to a depth of about
4 inches, so that the layer of night-soil was not disturbed by these operations.