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10. The water discharged from the pump was conveyed through a 7-inch cast iron pipe with water-tight joints to the point B at a distance of 350 feet from the well where it had a free discharge down the valley. This course prevented the water again finding its way into the well.

11. On the 3rd of December a meter was fixed on the discharge pipe for measuring the actual quantity pumped. Owing to a quantity of fine sand being met with on the 17th of December which blocked the meter, it had to be removed till the completion of the pipe laying was accomplished on the 27th of January.

12. A dam has been constructed of lime concrete across the valley at the point C 220 feet below the well to arrest the underground flow of water as suggested by Mr. CHADWICK, Section 10 of his report.

THE QUANTITY OF WATER TO BE DERIVED FROM THIS WELL AND Works

IN CONNECTION THEREWITH.

13. On the 3rd of December the whole of the water available was conducted into the well and after being pumped up passed through a meter. The reading of the meter at 12 A.M. on the 3rd was 2,254,800, and at 3 P.M. on the 8th 3,157,300 giving a flow of 902,500 in 123 hours, or at the rate of 7,337 gallons per hour, or 176,000 gallons per diem. Pumping was continued till 6 P.M. on 28th instant, and the water passed through the meter from 2.45 P.M. on the 12th (the meter reading 3,740,000) to 5.30 P.M. on the 16th (the meter reading 4,391,800) was 651,800 gallons giving a flow of 158,000 gallons per diem. From the 28th of December to the 1st of January no water was pumped. The engine and-pump were, however, started again at noon on the 1st of January and pumping continued till the 16th of March. On the 27th of January the pipes for collecting the underground water were completed. The flow of water from that date to the 3rd of February was at the rate of 186,000 gallons per diem when the meter was taken out for the purpose of cleaning, but pumping was still continued. On the 12th of February the meter was again fixed and the flow of water from that date to the 16th of March is shewn in the Table No. 1 attached.

14. In considering the foregoing figures it must be borne in mind that at the very commencement of pumping the valley was cut into and the water kept down for the purpose of laying the pipes thus draining it so as to leave no store of water in that portion of the valley where the pipes are laid, the gaugings are, therefore, practically those of the dry weather flow of the subsoil waters.

15. During the whole time continuous pumping was going on the water rose to the surface a few feet higher up the valley than the termination of the pipes, the sand being so compact as to prevent the water flowing sufficiently rapid to materially reduce its level beyond the actual point of its collection.

16. More water would probably be obtained for a limited period by further extending the drains up the valley, but such extension must be done with caution or the store of underground water in the upper portion of the valley will be drawn on to such an extent during the early part of the dry season as to materially diminish the flow of water towards the latter part of it.

17. The dam constructed across the valley at Cis founded on the practically impervious stratum underlying the sand and was completed in February too late to materially affect the flow of underground water to the sea this year, but it will doubtless play an important part in the future specially at the commencement of the dry season.

YIELD OF DRAINAGE AREA.

18. Considering the several points referred to in the foregoing, I am of opinion that during an average dry season these works may be relied on to give a minimum supply of 100,000 gallons of water per diem.

QUALITY OF WATER.

19. I am indebted to Mr. W. E. CROW, Government Analyst, for an analysis of a sample of this water collected shortly before stopping pumping. I attach his report. The quantity of Albumenoid Ammonia may be accounted for by the existence of some cultivated lands in the valley in close proximity to the collecting pipes. On the resumption of these gardens by the Government, which will be necessary if this source of water supply is adopted, and the prohibition of future cultivation of the soil within the drainage area, it is probable the quantity of Albumenoid Ammonia will diminish.

DISTRICTS TO BE SUPPLIED.

20. The Districts now urgently in need of a water supply are:-

Mongkoktsui population

Yaumati Tsimshatsui

17

"

Hunghom

>>

738

6,774

508 5,185

Total (Census 1891),............... 13,205