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construction.

12. I recommend that the dam be constructed departmentally, and not by Merhad of contract, so as to ensure perfect workmanship, an arrangement adopted by Mr. MANSERGH, Past President Inst. C.E., in the case of the dams for the Birmingham Water-works. At any rate, most careful supervision will be required. Competent European foremen or inspectors must supervise the work continuously. All cement should be provided by the Government.

the mass of

13. In the case of the Taitam Dam, the late Sir ROBERT RAWLINSON, K. C'. B., Drains in directed numerous small drains to be formed in the mass of the concrete behind the the inner lining of masonry intended to be water-tight, in order that should any water find its way through the said lining it would flow freely away, and not accumulate in any fissure or cavity, causing an upward hydrostatic pressure, tending to reduce the stability of the structure. I consider that this would be a wise pre- caution. In the case of Taitam it was not however adopte:l, because those in charge of construction thought that the concrete would be sufficiently porous, to prevent any such prejudicial accumulation. As a matter of fact, the Taitam dam leaks considerably through the mass of the concrete. I maintain that concrete should be impervious, the interstices between the stones being completely filled with mortar. Percolation through concrete tends to its disintegration. Mr. MANSERGH informs ue, that in the case of the Birmingham Dams, he is not draining the whole mass of the concrete, in the manner recommended by the late Sir ROBERT RAWLINSON, but he is taking every precaution to render the whole inass absolutely homogeneous and impervious. The only drains which he introduces are to remove the land springs. found in the excavations for the foundations, and he has also provided a single drain, at a low level, below the whole length of the dam, to remove any water which might by chance percolate through the water face, below the foundations, and this drain communicates with the out-let culvèrt.

area not to

14. The surface of the drainage area should be as little disturbed as possible, iminge the natural growth of herbage should not be broken up. The main reason why estarbed. the water of "Pokfolum Reservoir" is so turbid after heavy rain, is because so much bare soil is exposed, within its gathering-ground, owing to excavation for roads, and for building-sites.

15. In conclusion, I beg to record my opinion that the project for the water- supply of Kowloon is sound and one that may be sanctioned.

I have the honour to be,

Gentlemen,

Your obedient Servant,

OSBERT CHADWICK.

(Mr. Chadwick to Colonial Secretary)

Re NEW KOWLOON WATER WORKS.

GOVERNMENT OFFICE, HONGKONG, 13th May, 1902.

report and

design.

SIR-I have the honour to report that I have visited the site of the proposed Confirming works in company with the Honourable the Director of Public Works and with Mr. Previous GIBBS, C.E. I have also inspected the Plans, and fully discussed them with the rig said Engineers. I beg to confirm the opinion, which I have already expressed in a report dated 20th December, 1901, to the effect that the Design is in every way satisfactory; and that the Project is one that should be carried out forthwith.