THE FRESH-WATER LOCHS OF SCOTLAND. 



83 



readings, as a rule, were taken near shore, and the lower readings 

 towards the centre of the loch over deep water. When visited on May 

 28, 1903, the surface temperature at noon, about a mile from Kenmore, 

 was found to be 49'3. 



Two serial temperatures were taken beneath the surface in May, 

 1902, and one series in May, 1903, as given in the following table : 





It will be seen that on May 1, 1902, the temperature of the water down 

 to 30 feet was higher than on May 6, 1902, while from 50 feet down- 

 wards it was lower. The range of temperature between the surface and 

 a depth of 300 feet on May 1 was 3-5 (from 40-3 to 43-8), while on 

 May 6 it was only 1 (from 41 to 42). On May 28, 1903, the tem- 

 perature of the water was found to be considerably higher from the 

 surface down to a depth of 100 feet than was observed in the previous 

 May, the range of temperature in the upper 100 feet of water being 6 0- 8 

 (from 42-5 to 49-3). 



Loch Derculich (see Plate XXVI.). Loch Derculich, situated in 

 Strathtay amid beautiful scenery, affords good fishing, but is strictly 

 preserved; it flows by the Derculich burn into the river Tay to the 

 north-east of Aberfeldy. It is surrounded by low rounded hills covered 

 with heather, and there are few conspicuous boulders, but many small 

 ones. To the north are high, steep hills (Farragon, &c.), with grey 

 screes. The knoll forming the point at the boathouse on the south- 

 eastern shore is high and planted with trees. The burn flows out of the 

 loch by an artificial dam and sluice, which was open on the date of the 

 survey, and the water in the loch was very low, a long gravelly point 

 (not shown on the Ordnance Survey chart) appearing, and the island to 

 the north was nearly, while the island to the south was quite, joined 

 to the shore. Loch Derculich (pronounced Der'clich) is over half a mile 



