CAB38-17 — Page 41

Page 41

10

This position, it appears to me, is undoubtedly the present examination anchorage-Chung Kwango, commonly called Junk Harbour.

"To build a breakwater there would be a far easier and less costly undertaking than the proposed one between Green Island and Stonecutter's, for it is but 1 mile aguirst 2, and the chart shows mud and shingle; therefore the foundations should be an easy matter."

No estimate of the cost of the proposed breakwater is given, but it is clear that the cost of constructing a breakwater 1 mile long in 9 to 10 fathoms of water would be heavy.

The remoteness of Junk Bay from the mercantile harbour gives it considerable advantages as a war anchorage, but these advantages are outweighed by the cost of the proposed breakwater, and by the consideration that the bay lies outside the main line of the defences of Hong Kong. Its adoption as a war anchorage for battleships would therefore involve the enlargement of the defended area, and the construction of additional defences in a somewhat isolated position.

36. A further suggestion has been put forward by the Governor in paragraph 4 of his despatch of the 17th January, 1910, which is printed as Appendix III to this Memorandum:—

"4. The only question which has been referred to me is that of the defence of the harbour against torpedo vesels, against which, I understand, submarine mines would be ineffective. The subject of the reference was whether a rubble bank or an obstruction consisting of concrete blocks permitting a free flow of water between them should be constructed so as to partially close the open entrance between Green Island and Stonecutter's Island, along Kellet's Bank. I would suggest that a row of large sea-going junks, deeply laden with stones, and chained together bow to stern and anchored along the proposed line of this obstruction, would be a sufficient protection for the purpose required, and would form no obstruction to the free flow of tide. Such a measure would have the advantage of being cheaper than a permanent stone bank, and of not interfering with the tidal conditions of the harbour. It would, however, have to be withdrawn when a typhoon was imminent.”

The great length and consequent heavy cost and the inconvenience that it would cause to junk traffic constitute serious practical objections to an obstacle on this site.

The total width of the water between Green Island and Stonecutter's Island is 4,500 yards. The closing of this channel alone would not render warships lying in harbour secure against torpedo attack; for such attack might be delivered either by Sulphur Channel or by the channel lying to the north of Stonecutter's Island. These channels are 400 yards and 1,200 yards wide respectively, so that to afford complete protection from torpedo attack from the west on the system proposed by the Governor would involve the construction of about 6,100 yards of boom or similar obstacle, and even if the main western entrance were blocked at its narrowest point-i.e., from West Point to Centurion Battery on Stonecutter's Island, 3,500 yards-4,600 yards of obstacle would still be required.

37. The Admiralty are of opinion that in view of the great cost, the provision of boom defences for the protection of warships lying in harbour against torpedo attack is, in existing circumstances, unnecessary. Should this form of defence ultimately be required, the most economical way it could be provided would be by means of a boom running from Kowloon Point to Murray Pier in Victoria, a distance of about 1,700 yards, as a protection against attack from the western entrance, and by a boom closing the Lyemun Pass, which is only 400 yards wide, against torpedo attack from the eastern entrance.

38. For the protection of the warship anchorage it is considered that special fixed defences consisting of quick-firing guns and electric lights will for the present suffice. It is recommended that the following armament should be provided :—

(a.) Eastern Entrance. Four 12-pr. Q.F. guns, to be mounted at Pak-sha-wan. (The three 6-inch B.L. Mark VII at Pak-sha-wan will also be available to deal with torpedo attack.)

(b.) Western Entrance.-Two 12-pr. Q.F. guns to be mounted at Kowloon West,

and four 4·7-inch Q.F. guns to be mounted at Victoria

:

Page 41

Page 41

Page 41