384 
BATHYMETRICAL SURVEY OF 
width is 2 miles. The portion of the loch from Torr point to Bona 
ferry for about IJ miles varies in width from a half to a quarter of a 
mile, and the central portion of Loch Dochfour is about a quarter of 
a mile in width. The mean breadth of the entire loch is nine-tenths 
of a mile, or less than 4 per cent, of the length; a smaller percentage of 
mean breadth to length has been recorded only in Loch Shiel and Loch 
Shin, with and 3 per cent, respectively. 
The waters of Loch Ness cover an area of nearly 14,000 acres, or 21| 
square miles. Among the Scottish fresh-water lochs this is exceeded 
only by Loch Lomond, which has a superficial area of nearly 27J square 
riG. 60.^ INCHNACARDOCH BAY^ LOCH NESS, SHOWING CHEERY ISLANH AND THE 
“ HORSESHOE '' IN THE DISTANCE. 
(Photograph by Blr. G. West. From “ Proc. Roy. Soc. Edin.,” by permission of the Council.) 
miles. As already stated the area draining directly into Loch Ness is 
about 332 square miles, while its total drainage area, including the 
area draining into all the tributary lochs, is about 686 square miles — 
an area over thirty times greater than that of the loch. 
The maximum depth observed by the Lake Survey staff in Loch 
Ness was 754 feet, about a mile due south of Castle Urquhart in the 
centre of the loch. A greater depth than this has been recorded in only 
one Scottish loch, viz. Loch Morar, which has a maximum depth of 1017 
feet, and after Loch Ness come Loch Lomond and Loch Lochy, with 
maxima of 623 and 531 feet respectively. 
