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used as a fertiliser for the fields, and there is no difficulty in securing a Contractor who will pay a considerable sum for the sole right of removal. Revenue from this source is gradually diminishing owing to the substitution of water closets for pail closets.
The excrement is removed by night from the latrines to a special fleet of junks which convey it up river to China where it is utilised as manure for the mulberry trees on which the silk worms feed.
Owing to the limitations of the water supply on the Island and the need for economy in the matter of consumption, it is necessary to restrict the number of water closets served by the public mains. Where a sufficiency of water can be obtained from other sources such as wells or nullahs, water closets are allowed. With regard to effluents, some enter the public sewers direct, others pass to biological tank systems to be treated before final discharge.
Drainage. (Subsoil and Surface).-Drainage, both subsoil and surface, is controlled by the Public Works Department.
Water Supplies.-The water supplies of Hong Kong and Kowloon are in charge of the Water Works Branch of the Public Works Department.
All the water is surface water collected from catchment areas which are free from ordinary risks of pollution.
The water, after storage for a longer or shorter period in the impounding reservoirs, is filtered, in some cases by the slow sand system in others by the rapid system and finally chlorinated.
Routine examinations are carried out by the Government Bacteriologist and Government Analyst and the results furnished to the Water Authority. There was no evidence of any disease having been conveyed through the public water supplies.
Clearance of Bush and Undergrowth.-Generally speaking, in Hong Kong and the New Territories, bush and undergrowth is little in evidence except in those places where it has been planted and conserved. Routine cutting of superfluous undergrowth is carried out in May and October.