312 
Proceedings of the Royal Society of Edinburgh. [Sess. 
XY. — Current Observations in Loch Garry. By E. M. 
Wedderburn, W.S. 
(MS. received January 21, 1910. Read January 10, 1910.) 
Following on the current observations made during 1908 in Loch Ness* 
by the author and Mr W. Watson, a few observations were made in Loch 
Garry (Ness basin) during August and September 1909. Mr Macdonald, 
Fort Augustus, again assisted in the work. The Loch Ness observations 
showed that the currents in the loch were very confused, but certain 
general conclusions were drawn ; e.g. (1) that when a lake has become 
stratified and the temperature discontinuity has appeared, the return 
current is nearly always found above the discontinuity ; (2) that towards 
the windward end of the loch the return current may take place close to 
the surface ; (3) that slow currents are to be found below the discontinuity, 
and with the same direction as the surface current. All these conclusions 
are borne out by the Loch Garry observations, and some additional 
information has been obtained. 
Loch Garry is a much more convenient size for observation than Loch 
Ness. The main basin of the loch, in which the observations were made, is 
about 4 miles long, with a maximum depth of about 220 feet. A description 
of the loch will be found in the Lake Survey Reports, Geogr. Journ., 
vol. xxx. p. 401, 1907. Observations were made at two stations, viz. at the 
east end of the loch in about 100 feet of water, and at the deepest part of 
the loch. Buoys were moored in these positions as described in the paper 
on the Loch Ness observations. The observations were interrupted on 
several occasions by the breaking of the wire by means of which the buoys 
were moored, and it is thought that faulty wire must have been supplied, 
as the same method of anchoring answered well in Loch Ness. 
The current meter used was the same instrument as was used in Loch 
Ness, and after being overhauled it worked very well indeed. It was noticed 
that during very stormy weather the propeller of the meter had a tendency 
to move backwards owing to the jolting movement of the waves, so that 
the velocity of the currents recorded was probably rather greater than the 
instrument indicated. If any work requiring great accuracy is to be done 
with this instrument, further investigation into the effect of the jolting 
* “ Observations with a Current Meter in Loch Ness,” Proc. Roy. Soc. Edin ., xxix. 
p. 620. 
