TEMPERA TUKE OF SCOTTISH LAKES 
133 
Following the exceptionally severe winter of 1878-79 there is a 
very low abysmal temperature, but in the other cases the connection 
between the winter temperature and the abysmal temperature is not 
apparent. The effect of the wind is more apparent, for in 1877 and 
1892, when the bottom temperatures were high, the summer winds 
were much above the average. These observations indicate clearly 
that the highest point abysmal temperatures reach during a year 
depends on the strength of the winds, especially in summer, while 
the lowest point depends on the winter temperature and also on the 
strength of the winds during the winter — the stronger the wind in 
winter the lower the temperature, the stronger the wind in summer 
the higher the temperature. 
The Loch Garry observations were interesting from the point of 
view of the abysmal temperatures, for it was found that until the 
formation of the discontinuity the bottom temperature rose by fits 
and starts following on strong winds. 
On 6th May 1908 the temperature at the surface and at 200 feet 
was respectively 44° '5 and 41° '2, there having been little variation in 
the bottom temperature during the previous ten days. Owing to 
stormy weather, no observations were made on the 7th, but on the 
8th the bottom temperature had risen to 42°, a rise of 0*8°, showing 
the influence of currents produced by winds. A more marked case 
occurred about a week later. On 15th May the surface temperature 
was 46° '3, and at the bottom the temperature was 42°*3, showing a 
very slight rise in the bottom temperature. On the 16th and 17th 
the wind was very strong and no observations could be made, but on 
the 19th it was found that the bottom temperature had risen 1°*7, 
to 44° '0. There was a continuance of moderately strong winds, 
with the result that the bottom temperature had risen to 44° "5 by 
22nd May, and to 45° '0 by the 27th. Variable winds were experienced 
till 5th June, when the bottom temperature was only 45° '2, showing 
little variation for the previous nine days ; but the wind increased on 
the 5th, and observations on 6th June showed a bottom temperature 
of 45° "5, and on the 10th 46° '0. Thereafter the winds were light 
and the weather was cold, with the result that a discontinuity was 
formed. The bottom temperature remained about 46° '0 until the 
end of June, and during the month of July there was a gradual and 
fairly continuous rise, accompanied by moderate and variable winds, 
to 46° '5. On 6th September, when an isolated observation was made, 
the temperature at the bottom was 47° "0, showing that the gradual 
rise in bottom temperature was continued. After the formation of 
the discontinuity the rise in the bottom temperature was very gradual, 
and this is explained by the difference in the effect of winds after the 
discontinuity is formed. 
