262 
BATHYMETRICAL SURVEY OF 
LOCHS OF THE CLYDE BASIN. 
Within this basin (see Index Maji, Fig. 27) seven lochs were sounded 
by the Lake Survey staff, including one of the largest and most important 
of Scottish fresh-water lochs (Loch Lomond), which is interesting as being 
one of the two Scottish inland bodies of water surveyed “in the interests of 
navigation ” by officers of the British navy so long ago as 1861. The other 
loch surveyed at that time was Loch Awe in the Etive basin, to be dealt 
with later. With the object of determining what changes in conformation, 
if any, had taken place in the interval of over forty years. Loch Lomond 
and Loch Awe were sounded in 1903, and the results were carefully com- 
pared with those obtained in 1861, as shown in the Admiralty charts 
published in 1862 and 1863 respectively. Generally speaking, the depths 
recorded by the two surveys, both in Loch Lomond and in Loch Awe, 
agree very closely, and it was at first considered that it would be 
unnecessary to publish the soundings in these lochs, but ultimately the 
Directors decided, in order to render the account of the work of the Lake 
Survey complete, to issue the maps of these lochs in the same form as the 
other maps accompanying this volume. 
To the north of the Firth of Clyde, besides Loch Lomond, two neigh- 
bouring small lochs (Geal and Sloy) were sounded, and to the south of the 
Firth of Clyde, four lochs were sounded, viz. Kilbirnie Loch, Castle 
Semple Loch, Loch Thom, and Gryfe reservoir, the two last mentioned 
being artificial, and connected with the supply of water to the town of 
Greenock. 
Loch Lomond (see Plates CXXIV. and CXXV.). — Loch Lomond is so 
well known that there is no necessity to enter here into a detailed topo- 
graphic description ; the beauty of its surroundings, which is enhanced by 
the many large islands occupying the wide southern portion, has been 
referred to by many writers, and has earned for it the title of “ Queen of 
Scottish lakes ” (see Fig. 35). Briefly, it may be stated that the loch 
trends nearly north and south, and in a straight line is about 21 miles in 
length, but following the sinuous axis of maximum depth, the length is 
nearly 23 miles, Loch Lomond being exceeded in this respect only by 
Loch Awe and Loch Ness. The upper northern portion for a distance of 
12 or 13 miles from the head of the loch is narrow, mostly less than a 
mile across, but to the south of Boss point the loch opens out, and attains 
