Loth Katrine, a lake of Perthshire, Scotland, 9 1/2m. from Callander. It is of serpentine form, about 10 m. in length, and in some places nearly 2 m. in breadth, and is surrounded with lofty mountains and rocky ravines, displaying scenery of much grandeur and beauty. From its E. extremity flows a stream, which, after passing through the rugged defile of the Trosachs, widens into the two minor lakes of Achray and Vennachar, and becomes the river Teith, a tributary of the Forth. This lake was formerly a favorite resort of robbers, or caterans, and at a little distance from its shore is a small island called Eilan Varnoch, whither the freebooters used to bring their plunder, and which is the famous " Ellen's isle " of Scott's "Lady of the Lake." From this lake the city of Glasgow is supplied with water, which is carried 26 m. in pipes over a rugged and mountainous district, with 70 tunnels aggregating 13 m. in length, several aqueduct bridges in the form of iron troughs, and siphon pipes across wide and deep valleys.

The works were completed in 1859, at a cost of £1,500,000, and can supply 50,000,000 gallons daily.