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can), is a matter that requires careful consideration. In the case of Government buildings generally, they are scattered all over the Colony and the current used is small, but the installation of Destructors might be warranted by the demand for current say to Eastern Filter Beds, Government Workshops, Government Offices, Law Courts, Post Office, New Fire Station, Central Police Station etc., all of which are practically in a straight line for cables from the Power Station.
3. Destructors and Destructor Station :-These would be of a type best suited or modified to deal with Hong Kong's refuse, dependent on moisture and the ascertained calorific value of average samples. The clinker and residue could be disposed of in fur- ther reclamation works to the westward.
4. Engines and Engine House :-The pumping station has been shown to the south of the site where better foundations can be obtained for the engines, which would be of the triple expansion vertical type, in duplicate, each capable of lifting 3.3 million gallons per day against a maximum effective head of about 285 feet. The pumps, three to each en- gine, driven from the cross-heads would be of the piston type. Provision for workshop and Quarters for European and Chinese Staff would also be required.
5. Main Salt-water Service Reservoir :-The main salt water service Reservoir with a top water level of about plus 285′ O.D. has been placed in about the only available site that can be economically used for the purpose and would be covered in. It is shown immediately below the Albany and involves no resumption and very little disturbance of the Botanical Gardens which could be reinstated over the roof; it will not interfere with any future waterworks extensions. This reservoir of 14 million gallons capacity would supply what would be a low level zone north of and bordering on Pokfulam, Bonham, Caine & Kennedy Roads and the whole of the Eastern district as far as North Point (Broadwood Road excepted). These roads approximately draw a dividing line between two classes of property, and, for the purposes of a pumping supply, form a very con- venient divide between the low and high level zones, which make it possible to devise 2 schemes which can be made entirely independent of each other, should it be thought desirable to grant a fresh water flushing supply to the middle zone, by utilizing to their full capacity, all stream-courses on the northern slopes of the Island which are not used for waterworks purposes on account of pollution.
6. Balancing Tanks :-The balancing tanks shown on plan at Mount Parish, Leighton Hill, and north of Tin Hau Temple at elevations approximately of 200' 150′ and 120' respectively would be necessary to maintain pressure throughout this low level zone. The sites are fairly level and can easily be utilised for the purpose without costly site formation. The resumption of a small unbuilt-on area at the Naval Hospital at Mount Parish only is involved.
7. Pumping Mains :-The pumping mains shown on plan in black would be in 18′′ dia. C.I. socket and spigot pipes laid in duplicate each having a delivery of 3.3 million gal- lons per day.
8. Gravitation Mains:-The Gravitation mains shown in blue would supply the balan- cing tanks on Mount Parish, Leighton Hill and Tin Hau Temple from the Albany salt water Reservoir. They would also be in C.I. socket and spigot pipes of 15′′ and 12′′ diameter respectively and would feed the districts through which they passed.
9. Subsidiary Mains :-The subsidiary mains shown in red would also be C.I. socket and spigot pipes 6 inches in diameter and, as in the case of the gravitation mains, al- though somewhat of larger diameter than is necessary for the area served, they allow for marine growth and incrustation which would occur and the extra cost over that of the minimum size that could be laid is very small. They have been spaced as wide apart as possible generally to give house services along scavenging lanes on each side of the
street.
10. Scavenging lane mains These, which would be numerous and are not shown on plan would require to be of the best 2" galvanized iron piping and could generally be laid a few inches below the surfacing of scavenging lanes.