AT THE SEA BOTTOM

Evening Post, Volume CV, Issue 124, 26 May 1923, Page 14

AT THE SEA BOTTOM

PROBING THE DEPTHS BY SEARCHLIGHT. By mentis of an invention now in use on the Tyne a ship is able to throw a disc of light on the sea bottom, and the captain, as he. stands on the bridge or in the chartroom, can probe the depths with tho penetrating vision of a. fish. A pair of eyes to the bottom of the steamer gauge with mathematical precision: the depth "of water immediately below the vessel. This power of submarine vision enables the captain or navigating officer to avoid shallow waters and. to steer clear of hidden sandbanks or rocks. The Tyne pilpt steamer, the Queen of the May (says the London "Daily News"), which can be seen off the coast in all .weathers awaiting the summons oE homeward-bound vessels for pilotage up the Tyne, is fitted with such a pair of eyes, and the man who has performed the operation is Captain James Burn, a well-known pilot, of Julian avenue, South Shields. He has equipped the steamer with this novel system of continuous depth-finding, • which, he claims, removes the necessity of taking soundings by the use of the lead. Far below the waterline, somewhere amidships, a vertical beam of light is projected through a sort of porthole on to the sea bottom, a searchlight being used for the purpose. Some distance from the porthole, also far be-low the wateriiiie,_ is a little observation window, from which the beam of light can bo seen through the water. A mirror is used at the end of a long observation" tube, running vertically right through tho' ship to the navigation bridge. By working' a handle the captain can tcke an angle on. the projected bsim, and then", by a simple calculation, can. measure with accuracy 'the depth of water below ihs shig,.