THE SEA "TANKS"

Dominion, Volume 12, Issue 76, 24 December 1918, Page 5

THE SEA "TANKS"

LIGHT ON NEW UNDER-WATER MONSTERS

SINKING OF AN AUSTRIAN DREADNOUGHT

In the course of a descriptive article in tho "Electrical Experimenter," Mr. H. Winfield Secor discusses tho application of the "tank" idea to marine warfare, which, it seems, was successfully carried out by the Italians in their raid on Pola, whore they destroyed by this means a large Austrian warship. Tho sea-tanks, Mr. Secor tells us, measure about <10ft. by Oft., and are propelled by electricity. They are provided with an endless rotary chain, running' lengthwise around the vessel, and fitted with sharp steel barbs or knives, which can cut their way through nets and other obstacles just like their prototypes, tho land-tanks, first used so effectively by the British. He Roes on:

"This -underwater demon is provided with several torpedo tubes at the bow, and from all accounts it seems that the device was crewless, and operated by means of electrical control currents sent through a flexible insulated cable connecting with a war vessel, which latter nosed its way up to within a few miles of the steel nets guarding the harbour of Pola. The account of tho attack on Pola by the Italian sea-tanks states that'they bored their way through the heavy steel nets spanning the navigable anproaehes to the port, within which there lay at anchor Austria's fighting -fleet;, and tlmt'n mighty Austrian 1 battleshin of tho Viribus Unitis typo of about 20.000 tons displacement was torpedoed." ' Hero follows a description of the interior of the Italian underwater tank, and J'.lso the arrangement whereby the steel belts carrying the not-cutting knives or barb? are driven by powerful electric motors, whicli obtain current from a storage battery carried in -the undersea craft, or from electric energy supplied through the cable connected with it.

A Deadly Automaton. "It is entirely feasible, for.a device of this kind to be controlled by a warship of the destroyer class at a distance of seven miles, or even eight to ten miles or more, With ingenuity and ttte proper desiirn of the device of the type here under discussion, and also in consideration of the undoubted and proved cleverness of the Italian engineers, there is no doubt but what such a device could be sent out, and steered so as to be submerged when it nenred the steel nets, and to boro its way through them, and then to rise agnin; also at this juncture the observation officer on the war vessel, looking through his night glasses, could press the proper 'electric control nnd cause one or more torpedoes to be discharged at an enemy war vessel in tho manner described in the report from Rome, which now forms a part of It.nl ian naval history."

In any event. Mr: Secor concludes, the sen-tank would appear to be invulnerable iiTainst harbour nets and the like, and when designed to carry a crew nnd equinned with underwater searchlights should prove effective 'in clearing nut minefields, particularly such mine-infected waters as those leading up the grent German naval base at Heligoland. He goes mi:

"This manoeuvre by the Italian seatanks in their attack on Pola may seem oil the more practical and possible to the layman when it is considered that the entire Gulf of Venice is very shallow—about 120 feet-at greatest depth— and such an uiider-wnte.r fighting monster might, crawl even along the .bed of the Gulf of Venice and tncklo the steel nets nnd mines protecting Pola, much in the same manner as a gigantic turtle would crawl along the bed of a lake. In fact, some engineers venture the opinion that with the proper design of the moving caterpillar belts and barbs, the tank could be made self-propelling in the same manner ns just mentioned.

"It is most probable, however, that the Italian sea-tank as now used is fitted with powerful propellers, the same as the submarine, and also, that it Ims a suitable rudder for the purpose of steering it, To prevent the cable /from becoming fouled in the propeller blades, the latter are encased in substantial steel cages. The pilot light or lights are provided with shields at the front, so as to throw intermittent signal flashes sternward, and by "arranging this on a telescopic mast the officer i« charge can, by simply pressing' the proper button, caiise them to rise 10 or 15 feet above the back of the sea-tank while it .is progressing through the water near its objective. "When 'the tank has progressed sufficiently near the net c-r other obstruction it is to burrow through the proper electrical impulses are sent over the electrical control cable, which starts up the water-ballast tank motor, and by filling the tanks the craft is (aused to submerge. It is a simple .matter, and one which ■has been used heretofore to provide a suitable electrical position-indicating arrangement, whereby it becomes possible to know at any instant the direction and location of the sea-tank while it is submerged.

"By means of a sensitive -microphone installed in the vessel, it would be possible to ascertain wheii the tank had chewed its way through the enemy nets, and it could then be raused' to appro* h the surface again, if so desired. It is not, however,- imperative tliat the vessel be made to come to the surface so as to show the signal light, for by means of the position-indicating apparatus just described its exact position at anr moment could be known qnd torpedoes discharged from it at an enemy war vessel swinging at anchor within' the netted area." '