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Scientific Memoirs by

parallelogram, as regards the most economical laying of the latrine drain pipes and
their linking up into a larger connecting drain which will conduct to the installa-
tion; but given a sufficient natural fall in the ground this is a matter of detail
presenting little or no difficulty.

   Take the case of the ordinary company-barrack, to each of which is attached
a latrine and a lavatory. The present pan arrangements of the former should be
dismantled; the present flooring and the soil around the latrine should be
removed and renewed and the whole site and structure be thoroughly disinfected.
It should then be fitted with automatic flush W. Cs. of which good and
reliable patterns will be cited; these should be raised to a sufficient height
above the old floor level to provide an adequate fall for the soil pipe which
should run from end to end of the latrine, receiving the discharges of the series
of W. Cs., and itself discharge into the connecting drain. If, for example,
the closets are raised some 4 feet above ground-level, we at once secure a
gradient of 1 in 30 for the first 40 yards of the system, that is, until the con-
necting drain is reached, which may therefore take-off at surface level and still
have the whole of. the natural gradient available.

   Of self-acting flush water closets one of the best, strongest and most reliable is
Shank's supplied to the new General Hospital, Calcutta, by Messrs. Norton and Sons.
When the seat is released by the user, a 3-gallon flush is discharged from the cistern.
Price, Rs. 80 (approximately). An equally good and reliable apparatus is that devised by
Mr. Donaldson for use in the Presidency Jail, modified for Europeans' use. The self-
acting flush is worked by the seat as in the former pattern and is simple in construction
and not likely to get out of order. It could be supplied for about half the cost of the
former, viz., about Rs, 40. Drawings can be supplied if desired.

   A "flush-trench" latrine might be devised in place of W. Cs., but it has several
disadvantages; there is splashing from the fall of the excreta, and the trench on its upper
edges must get encrusted with the deposit of organic matter, and this will entail subse-
quent hand-labour for its removal, and here a factor is introduced which we wish to
eliminate. There will also be waste of water beyond requirements, and some necessary
exposure of the excreta before removal, even if an automatic tip flush is provided which
also involves waste; it lacks many of the advantages of cleanliness and of immediate
removal so essential to attain.

   For the supply of flushing water two sources are available, viz. , that from the
lavatory, and, preferably, a separate supply of fresh water, which would only
amount to some 300—350 gallons per company, and which, as in the present case
of the lavatories, would have to be conveyed, by hand, or pump to a reservoir
placed at a higher level (7 or 8 feet) than the W. Cs.; if water can be conveyed to
a tank in the lavatories, there can surely be no difficulty about the latrine supply.
In case this desirable separate supply of 3 gallons per head could be arranged,
the whole of the lavatory waste could be utilized for flushing purposes, by
being conducted to a siphon flush tank discharging at the head of the main drain,