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enter them for hostile purposes. The Admiralty expressed the opinion that there was no reasonable probability of a hostile ship attempting to force an entrance into one of our commercial defended harbours. They explained that the degree of probability of large vessels acting thus will be governed rather by the strategic exigencies of war than by the difficulties of navigation. So far as natural obstacles are concerned, s hostile cruiser would, as a rule, find no difficulty in entering a harbour; but to expose herself in the cramped channels of approach without power to manœuvre to the effective fire of the fixed defences would be a misapplication of force so unjustifiable that it cannot be regarded as a reasonably probable contingency in war.

It was accordingly decided that all submarine mines in the fairway of British commercial ports should be removed.

44. The decision as to the withdrawal of the submarine mine defences from the fairways of defended harbours was not intended to preclude the use of submarine mines in unfrequented waters-such as bays in which a landing is possible or in other waters which it might be desirable to deny to an enemy. But as the Admiralty expressed the opinion that none of the minefields then existing fulfilled this condition, it was decided that all the submarine mine defences should be removed.

45. In view of the change of conditions affecting the defence of Hong Kong, the Admiralty are now of opinion that mine fields at the Eastern Entrance Channel between Cape Collinson and Junk Island, and at the Western Entrance in Sulphur Channel and north of Kellet Bank, would prove an effective deterrent to close-range attack by armoured ships.

The Colonial Defence Committee suggest that mines might also with advantage be laid on the western side of the Eastern channel up to Cape Collinson to deny the dead water there to approaching ships, and they further suggest that the desirability of laying mines in the neighbouring bays where landing operations are practicable, in order to deter transports from approaching, might be considered by the Admiralty.

The Colonial Defence Committee understand that the Admiralty have not over- looked the possibility of this form of defence being required in certain circumstances, and that they will be prepared to provide and to lay submarine mines where necessary.

XII.-Local Naval Defence.

46. The Royal Commission on the Defence of British Possessions and Commerce Abroad, which reported in 1882, recommended that floating defences, consisting of gun and torpedo-boats, should be provided as accessories to the local defences of certain ports where the hydrographical conditions were favourable. The Admiralty have, however, always been opposed to surrendering the power of disposing of any portion of the forces at their disposal in accordance with the strategic requirements of the moment, and they decline to allot vessels permanently to the defence of any particular locality. No action was therefore taken on this recommendation at the time it was made.

47. Although the Admiralty have not assented to any departure from this principle, modern developments have of recent years led to the maintenance of flotillas of destroyers and submarines at certain naval ports as an adjunct to the local defences. Such vessels are not regarded as unconditionally allotted to the local defence of these ports; for so soon as our naval superiority has been asserted in such a way as to preclude the danger of oversea attack in force, these vessels would become available for service wherever required.

48. The presence, or even the suspected presence, of these vessels would probably deter an enemy from risking the destruction of warships and transports by approaching Hong Kong until the destroyers and submarines had been disposed of.

A necessary preliminary to a landing in the neighbourhood of Hong Kong would be the destruction of these flotillas, which would probably take some time to effect.

An efficient local naval defence flotilla would thus curtail the period that the enemy would have at his disposal for delivering attack by a military landing force without fear of interruption, and would therefore exercise a considerable deterrent influence against operations of this nature.

Hong Kong is now a station for destroyers and torpedo-boats, and the Committee understand that the Admiralty propose to establish a submarine flotilla there in the near future.

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