THE FRESH-WATER LOCHS OF SCOTLAND. 
35 
approximation to the total amount of rain falling annually on the 
drainage areas of the lochs draining into the river Teith, although the 
available records are far from sufficient for the purpose. Dr. Alexander 
Buchan, f.k.s., has kindly supplied us with information regarding the 
readings of the rain-gauges at observing stations within, and in the 
vicinity of, the catchment-basins of these lochs. The positions of these 
rainfall stations, and the mean annual rainfall, are shown on one of the 
accompanying maps (see Plate III.), and further particulars will be 
found in the following table : — 
station. 
Height of 
rain-gauge 
above 
sea -level. 
Years observed. 
Mean annual 
rainfall in 
inches. 
Ardlui 
Feet. 
50 
1865-70 
115-10 
Firkin 
100 
1866 -79 
98-38 
Arrochar 
15 
1864-98 
81-31 
Head of Duchray ... 
1800 
1854-98 
84-27 
Glengyle .. .' . 
380 
1854-98 
92-25 
Top of hill, Loch Katrine tunnel 
8.30 
1861 98 
77-95 
Brig o’ Turk 
270 
1854-98 
64-47 
Loch Drunkie 
420 
1861-98 
63-62 
Loch Vennachar ... ... 
275 
1861-98 
57-31 
Between Ben Ledi and Glen Finlas 
1800 
1854-98 
53-68 
The Gart 
230 
1872-98 
54-47 
Leny 
345 
1861-98 
54-23 
Blaircreach ... 
460 
1893-98 
82-63 
Stronvar 
4-22 
1860-98 
75-49 
Lochearnhead 
3-20 
1866-84 
65 -50 
Tyndrum 
792 
1858-61, 72-3, 76-7 
99-10 
Grouping these stations and their mean annual rainfall into those 
likely to represent the rainfall on the catchment-basin flowing out of 
Loch Vennachar, and those representing the rainfall on the catchment- 
basin flowing out of Loch Lubnaig, we arrive at an average rainfall of 
76’25 inches for the Loch Lubnaig catchment, the mean height of the 
rain-gauges being 538 feet above the level of the sea, and an average 
rainfall of 75-37 inches for the Loch Vennachar catchment, the mean 
height of the gauges being 528 feet. 
The entire catchment-basin flowing out of Loch Vennachar {i.e. the 
combined drainage-areas of Lochs Katrine, Achray, Drunkie, and Ven- 
nachar) is about 75-29 square miles, and the mean height calculated 
from the bulk of land above the level of the lochs is about 704-185 feet; 
the mean height of the surfaces of these four lochs above sea-level is 
3314 feet, so that the mean height above the sea of the entire catchment 
is about 1035-685 feet. The entire catchment-basin flowing out of Loch 
Lubnaig {i.e. the combined drainage-areas of Lochs Voil, Doine, and 
Lubnaig) is about 73-39 square miles, and the mean height above the 
level of the lochs is about 935-129 feet; the mean height of the surfaces 
