CLYDE SEA AEEA. 27 



pletely covering the Area, but individually occupying a considerably longer time in 

 doing so than was taken by the thirteen trips already touched upon. 



Trip XIV., November-December 1887. — From September on to the end of 

 the year the mean temperature of the air over the Clyde Sea Area was considerably 

 below the average for the season, contrasting in this respect with the abnormally mild 

 autumn and early winter of 1886, and serving to accelerate the process of cooling-down 

 from the great warmth of the summer maximum. The trip was in two parts. The first, 

 November 5th to 8th, was devoted to Loch Fyne. The weather was calm on the 5th ; 

 on the 7th, stormy, with a fresh breeze from the north-east blowing down the loch, and 

 producing very marked changes of temperature; and on the 8th, a light breeze from E.S.E. 

 The second part, from November 29th to December 10th, took account of all the remain- 

 ing divisions of the Area. The first day was calm. From December 2nd to 8th the wind 

 blew freshly or strongly from the west, south-west, or south. On the 9th and 10th 

 it was light and northerly. At the bottom of Loch Fyne the temperature was 45°"5 ; 

 at the bottom of Loch Goil 49°*4, the highest ever found there. In the Channel the 

 water was at 49°' 8, showing rapid cooling since September. Surface temperature 

 diminished rapidly landward, and came to a minimum of 42° in Loch Goil. The surface 

 was everywhere colder than the deeper layers, the vertical curves everywhere showing 

 the typical negative slope of winter. The warmest water was found, curiously enough, 

 in Loch Strivan, where all beneath 5 fathoms was at 50°"1. 



Trip XV., December 1887 '-January 1888. — This trip extended from December 

 15th to January 8th, and during it particular attention was given to the conditions of 

 the Upper Basin of Loch Fyne, with special reference to the influence of wind. All 

 parts of the Area were visited. December was considerably below the average of the 

 season with regard to air-temperature. During the cruise all varieties of weather were 

 found. It commenced in a calm, followed by variable airs, which on the 17th developed 

 into a heavy gale from the west and north-west, blowing across Loch Fyne. On the 

 18th there were heavy squalls from the north-west, but the rest of the month had only 

 light winds. On the last day of the year, when the Great Plateau was being examined, the 

 breeze blew fresh from the west, changing to S.S.E., and increasing in force on January 

 1st. The last week was characterised by light winds, usually from a southern quarter. 

 No observations were made on this trip in the Dunoon Basin, or the lochs with which 

 its northern end communicates. 



The water of the North Channel was at 47° "3 ; that in the middle of Loch Fyne, 

 although sandwiched between colder layers, remained the warmest (48°'5) in the Area, 

 so far as the observations could show. Except in Loch Fyne, which was warmer, the 

 temperature of the Area at five fathoms averaged 45°, and at 30 fathoms a little over 

 46°, showing how rapidly surface-cooling was at work. It is noticeable that, as in the 

 previous year, the Channel temperature remained higher than that of the partially 

 enclosed waters inside the Great Plateau. 



Trip XVI., January 1888. — The month of January was, like February of the 



