30 DR HUGH ROBERT MILL ON THE 



to be made with the state of matters in the northern lochs of the West Coast visited by Dr 

 Murray in the "Medusa" from April 20th to May 23rd. On April 20th a sounding off Jura 

 in 103 fathoms gave an average temperature of 43°'3, and on the 21st, somewhat farther 

 north, in a slightly deeper place, the average vertical temperature was 43°"6. Off Kerrara, 

 on the 23rd, the water, 57 fathoms deep, was perfectly homothermic at 43°*5, and on the 

 22nd, in the Firth of Lome (114 fathoms), there was a homothermic temperature of 45°; 

 but on May 9th the constant temperature was 44°*2. These observations were made in 

 places fully open to the sweep of Atlantic currents, and it is curious to notice that the 

 water was warmer in the more northerly positions. The mass of Loch Linnhe, Loch Aber, 

 and Loch Sunart had a uniform temperature of about 44° "5 ; and Loch Etive, which was 

 very carefully studied on two separate occasions during the trip, showed still higher 

 temperatures ; maximum readings of 49 o- were found at 26 fathoms in the deepest part, 

 and a minimum of 44° - 6 on the bottom. Nowhere were readings found approximating 

 to the conditions of the Clyde Sea Area, and the suggestion arises that the broad shallow 

 plateau across the entrance to the Area must, about the period of the annual minimum, 

 exercise an independent chilling influence on the inflowing water passing over it. 



Trip XXI, June 1888. — From the 2nd to the 11th of June observations were made 

 on six days, most of the time being spent in a very detailed examination of the Gareloch 

 and Loch Strivan, although Loch Fyne and part of the Arran Basin were also visited. 

 May had been a month of normal air-temperature, but June was rather below the 

 average in that respect. The wind was light as a rule, but on the 5th it blew freshly 

 from the south-east ; on the 7th, when the Gareloch was under investigation, it was 

 easterly, and sometimes very strong, blowing transversely to the loch. On the 9th, 

 when Loch Strivan was similarly examined, the wind varied from west to north-west, 

 and rose at times to a fresh breeze, blowing, on the whole, down the loch. 



Dr Murray dealt fully with the observations in his article in the Scottish Geo- 

 graphical Magazine already cited. They showed, taken generally, that rapid warming 

 was in progress, the Arran Basin having warmed up to an average vertical temperature 

 of 44°"5. This June was much colder than that of 1887, although warmer, so far as 

 regards the deeper water in particular, than that of 1886. It is interesting to notice 

 that there is no trace of the intermediate minimum in Loch Fyne which was so 

 prominent and puzzling a feature of 1886. 



Trip XXII., August-September 1888. — Observations were made on twelve days 

 between August 14th and September 8th. The summer had been the coldest of the three 

 during which observations were made, the air-temperature being as much below the 

 average for the three months June, July, and August as it had been above the average 

 for the same months in 1887. During the observations the weather was, as a rule, 

 warm and calm, strong wind being experienced on only two occasions, August 27th and 

 September 6th, both times a stiff breeze from the south-west. Surface temperature was 

 highest in the lochs, reaching 60 o, in Loch Fyne, and lowest in the East Arran Basin, 

 where it was 55°*0. The average temperature of the vertical sections was, as might be 



