/4 DR HUGH ROBERT MILL ON THE 



Beacon.* They were made as rapidly as possible in buckets of water drawn for the 

 purpose at intervals of a minute, or in some cases less. On April 19, while passing up 

 the loch in the "Medusa," we observed between 15 b 12 and 15 h 25, passing the Beacon 

 at 15 h 22. The tide at the time was about half-ebb, running out of the loch with about 

 its maximum velocity. At 15 h 12 the surface temperature outside Loch Fyne was 43° "4, 

 and this diminished to 42°'9, 43 o, 0, 42°7, 43 o> (at 15 h 16l), 18, 18J, 19£, then remained 

 at 43° until 15 h 22, when at the Beacon it rose to 43° '2, and retained that value through- 

 out the Gortans Basin. Here the ebb tide produced a perceptible cooling of the surface 

 water just outside the loch, the total amount being about half a degree, indicating an 

 upwelling of the slightly colder lower layers. 



On June 22nd, 1886, observations were made at longer intervals coming down the loch. 

 A surface reading was taken every ten minutes from 14 h 50 to 15 h 40, passing the Beacon 

 at 15 h 20, within an hour of high tide, the current setting in slowly. The resulting read- 



ings were 



Beacon. 

 N.E. 47°-9, 47°-0, 46°"5, 45°-7, 45°0, 46°-7. S.W. 



The minimum occurring, as before, outside the loch entrance. 



The soundings on June 21st (see Loch Fyne, Section II., Plate XII.) bring out an 

 exactly similar distribution as prevailing at 15 h 25, with the tidal phase rather more than 

 an hour earlier, and a stronger current consequently running in. 



On August 10th at 16 h 20-17 h a set of surface temperatures was taken which 

 showed a fall from 52°'l to 51°"3, and a rise to 52°'2 in passing the Beacon; although 

 a mile further up the loch, the temperature again fell to 51°*6. The tide was 1|- hours 

 flood, setting in strongly. 



On the following day about 16 h the observations were repeated in leaving the loch, 

 with the tide about low water, and the fall of surface temperature was found to be from 

 52°'5 to 51 0, 6, with a subsequent rise to 52°"6 outside. (See Section III., Plate XII.). 



On September 26th the Beacon was passed going up the loch at 15 h 6. Observations 

 every ten minutes for an hour previously showed a uniform surface temperature of from 

 53°"4 to 53°*2 to prevail all the way from Kilfinan Bay, but at 1 5 h 8 it dropped to 52 0, 9 ; 

 then at intervals of ten minutes going up Loch Fyne the readings were 53°"0, 53°"0, 

 52° # 9, and 5 2° 7. Here all that was shown was that the surface water in Loch Fyne was 

 about half a degree colder than that outside, the slight change taking place at the entrance. 

 The day was calm and dull, the tide was about the end of flood, within an hour of high 

 water. 



On 16th November 1886, the Beacon was passed at 13 b 20 going up the loch with 

 tide i\ hours flood ; the temperature ranged from 49°'8 to 49°*4, reaching that minimum 

 at the Beacon, and then rising to 49°'5 and 49°*6. The effect was almost too slight to 

 be relied upon ; but on the following day (see Section V., Plate XII.) it was visible to 

 precisely the same extent. 



* Jouru. Scot. Met. Soc, vol. viii., No. 4, pp. 108-110. 



