A Little Known Engine of War and its Wonderful Work on Hostile Coasts There was present in Shanghai on Monday an expert on the subject of coastal motor boats. The work of this type of craft, less than almost any other phase of warfare, has remained' a sealed book to the general public, for while the newspapers during the war were able to talk with a certain fluency upon "hush" ski they went very shy on the matter of C.M.B.'s until the attack on the Bolshevik men-of-war in Petrograd harbour took place subsequently to the armistice and was a part of the all but success-fu] offensive of General Yudenitch. As a matter of fact, these coastal motor boats, in differing types, were operating from 1916 onwards, and they carried on an offensive against Zeebrugge long before the brilliant Vindictive exploit. They are wonderful boats, brought to a remarkable pitch of perfection as they are to-day,. and one_ will pecbebly shortly be seen in Shang-Our readers will probably find it interesting to note how these coastal motor boats work. They are very highly powered craft, doing 40 knots and drawing about 3 ft. of water. Their particular offensive weapon is the torpedo. carried in a tunnel running under the centre of the boat. In the attacks on Zeebrugge and Petrograd these boats proceeded into the hostile harbours at full speed, got as near as possible to the man-of-war they wished to attack, say between 1,000 and 500 yards, and aligning themselves on the ship, discharged their tor-pedees. They carried no compressed air, but there was a charge of cordite in the torpedo tube. carried in the, tunnel afore-mentioned, and this gave the necessary impetus to carry the torpedo clear of the craft itself, travelling as it was at about 50 miles an hour. Then they could bolt equally quickly. In addition, these boats could be used as mine-layers. and so_were extraordinarily useful.
In those days the thing to give the presence of these craft away was the noise of their engines, but this was overcome in a very simple manner. It is practically impossible to distinguish between the beat of an aeroplane and that of a motor boat, so when a C.M.B. attack was in progress aeroplanes were sent up to attract attention, which they did most successfully, the eyes of the whole world at that time being on the air. In the case of an attack to-day that would not be necessary, for so great an advance has been made in the matter' of silencers that one of these craft might shoot noiselessly out of the mist or darkness and discharge its torpedo at the unsuspecting foe before the latter could be aware of its presence. Searchlights might
Text read from the printed page and cleaned; old type leaves the occasional error.