TORPEDO DEFENCE.

Globe, Volume VIII, Issue 915, 31 May 1877, Page 3

TORPEDO DEFENCE.

In an article on Lord Charles Bercsford's ; speech on torpedoes, the Times of March 23rd gives some interesting particulars of the pro--1 gress of torpedo defence. The Admiralty are about to build, at the suggestion of Sir G-eorge Sartorius, a kind of torpedo ram. " She will cany no guns, and she will be her qwu projectile, By the mere force of her

impact, assisted probably by some torpedo action, she will deliver blows for which we have as yet relied upon heavy guns. Rams have hitherto been combined with guns ; but it now seems proposed to build a ship which will be protected by armour from the fire of guns, and will rely upon her ram alone. Mr Ward Hunt does not, of course, suppose that she will supersede other types of ships; but lie ventures to hope she may prove an effective counterpoise to such monsters as the Italian vessels.

" But while we are devising huge engines of war of this kind —for even the ram, if it is to be effective, must be a vessel of great size and power —another invention is being gradually perfected, which threatens, at least under many circumstances, entirely to neutralise them. A torpedo may be regarded as a gun which dispenses with a gun carriage, and which, without the vast and expensive agency of a great ship, inflicts as formidable a blow as that of the heaviest artillery. It will be sufficient to mention three kinds of torpedoes. There is, first, the ' ground torpedo,' which is a sort of sunken mine, exploding either by contact or by electricity. If these are judiciously laid down around a harbour or anchorage, the approach of hostile ships may, apparently, be rendered impracticable. Every channel maybe protected by these hidden mines, and they may be made so powerful that any ship under which they explode is sure to be rendered powerless. There is, secondly, what Lord Charles Bcresford called the ' spar torpedo,' which is carried in a boat, no matter how small, and which also explodes by contact or by electricitv- We jmblished last week a most remarkable account of experiments at Cherbourg with a torpedo boat of this kind. It was a little vessel, called the Thornycroft, which was almost submarine. A very small part of it was above water, but it was of sufficient size to carry engines and two lateen sails, and it was worked by a lieutenant, two engineers, and a pilot. The French Admiral had two disabled ships in succession towed out to sea at a speed of fourteen knots an hour. The Thornycroft, however, was able to go at a rate of nineteen knots an hour-a rate not attained by any vessel in the Squadron. She very soon caught up her prey, delivered her blow with a torpedo which projected from her bow, and rebounded. 'A rent as big as " a house " was made in the side of the ship attacked and she sank at once. The Thornycroft only spun round and round for a few moments, and then return uninjured to the Squadron from which she had started. A vessel of this kind is scarcely discernable in the! water; even if she were detected, she is so small that it would be difficult to hit her ; and half-a-dozen' Thornycrofts attacking a large vessel would be a most dangerous foe. Their expense is quite trifling compared with that of great ships of war; they could be multiplied indefinitely, and, no doubt, they could be carried on board other ships and be launched from them as occasion might require. But even this formidable engine, which, perhaps, is as yet only in its infancy, seems surpassed in destructiveness by the Whitehead Torpedoes. These, as described by Lord Charles Beresford, arc a kind of automatic projectiles. They are some six yards long and. of the shape of a cigar, pointed at both ends. They arc made in three compartments, the head containing the explosive charge, the centre being a balance chamber which enables them to be adjusted to travel at any depth under water from one foot to thirty feet, and the third compartment consisting of an air chamber, which contains engines, and compressed air to drive them. It will travel under water for a distance of 1000 yards, and can be set so as to explode either on contact or after passing a given distance —in artillery language, either by a percussion or a time fuze. It ' can be fired above the water; but will at once go to the depth it is set for, and then go straight to the object, no matter how fast the ship from which it is discharged is sailing, or how fast the object aimed at might be sailing or steaming. In fact, it could do everything but speak,' and the hole it makes on striking is said to be 70ft in area. It is evident that by this means a comparately feeble ship, if only able to approach within 1000 yards of a larger one, could discharge a deadly flight of unseen projectiles at her, and at night such an attack would probably be wholly unsuspected and scarcely open to resistance. Attempts are being made to devise wire nets which may be spread around vessels at anchor, but it seems to be thought this torpedo would break through them. Allowing, however, for the imperfection of particular inventions, there seems sufficient reason to apprehend that some of the most powerful destructive agencies will in future be lodged in small craft or submarine torpedoes, and that the guns of the most powerful vessels will be less certain in action and less deadly than these comparatively inexpensive and slight instruments. For the purpose of defending harbours torpedoes would appear to be almost invincible ; but it seems very probable that half-a-dozen Thornycrofts or Whitehead torpedoes might prove a more formidable enemy to the Devastation than the Dandolo and the Duilio combined."