Blackwood's Magazine/Volume 1/Issue 2/White's New Invented Horizon

white's new invented horizon.

 

mr editor

It is well known, that, at sea, when the natural horizon is obscured by thick or foggy weather, the sun's meridian altitude, for ascertaining the latitude of the ship's place, cannot be observed; consequently, the navigator has nothing to depend on, until noon next day, to regulate his future proceedings, except his dead reckoning. In the English Channel, the North Sea, the Banks of Newfoundland, the Coast of America, and many other places of the world, the fogs are often so thick, and of such long continuance, as to render it impossible to ascertain the true position of the ship, for want of the latitude. Under such circumstances, although the sun is seen very distinctly, and felt very powerfully, there is no other alternative but to keep the ship at sea: for no man in his senses will run for a port, in such weather, without being pretty certain of his latitude.

To obviate these hitherto insurmountable obstacles, Mr Gavin White, grocer in Kinross, has, by a wonderful effort of uncultivated genius, invented a very simple apparatus,—with which, when fixed, by an easy process, to the common quadrant, an artificial horizon can thereby be obtained, and the sun's meridian altitude observed, the same as if ascertained with a quadrant and natural horizon, in the common way made use of on board a ship at sea.

This apparatus is, at present, made so as to screw on to my brass sextant, with which I have made many observations, not only for determining the latitude, but also for ascertaining the true apparent time; which, from the accuracy of the whole, enables me to pronounce the invention one of very great importance to science and navigation.

A large series of observations have been made with it, both on shore and on board the Ramillies, now in Leith Roads, which have been forwarded to some gentlemen, eminently distinguished for scientific knowledge and acquirements, in this city; who, with a very laudable zeal for the promotion of science, have interested themselves in such a manner, as, it is hoped, will ultimately prove highly beneficial both to the invention and inventor.

W. Bain, Master, Royal Navy.

Edinburgh, May 6th, 1817.