108 
BATHYMETRICAL SURVEY OF 
the many islands there are numerous large boulders projecting above the 
surface of the loch, The surface on October 25, 1906, was 264*6 feet above 
sea-level, and fully 16 feet higher than Mochrum Loch; the elevation 
found by the Ordnance Survey on April 15, 1893, was 264*2 feet above 
the sea. The temperature was 48°*0 Fahr. throughout. 
Mochrum Loch (see Plate XLI.). — The Mochrum Loch, the largest in 
the basin, is situated nearly midway between the tov/ns of Wigtown and 
Glenluce. It is of very irregular form, with rocky shores and many 
rocky islets, the largest of which are covered with trees. Westward to 
Castle Loch stretches flat boggy moor, on the east is cultivated ground and 
woods. The length is Ij miles, and the greatest breadth nearly one-third 
of a mile. The depth is very low (mean 7 feet, maximum 13 feet), the 
bottom in the open parts of the loch nearly flat or gently undulating. 
The area is about 230 acres, or one-third of a square mile, and the volume 
of water 68 millions of cubic feet. The drainage area, including Castle 
Loch, is about 4 square miles. The only considerable feeder is the burn 
coming from Castle Loch. The Water of Malzie issues from the east side 
of the loch, and flows some 5 or 6 miles in an easterly direction to join 
the river Bladenoch. On the date of the survey, October 24, 1906, the 
surface was 248*15 feet above sea-level; the elevation determined by the 
Ordnance Survey on March 27, 1893, was 247*7 feet above the sea. 
The temperature was 48°*4 Fahr. at the surface, and 48°*0 at 10 feet. 
