CLYDE SEA AREA. 



103 



the Channel, Arran Basin, and Loch Fyne were respectively 1°7, 1°"2, l° - 3 ; and in 

 1887, 1°7, 2 0, 3, 1°*7 ; or on the average of the two years, l°-7, 1 0, 7, 1 0, 5. The figures 

 for the Arran Basin are probably the least trustworthy ; but it appears that the isolation 

 of Loch Fyne has practically no effect on the relation between the temperature of the 

 lower strata of the air and the upper strata of the water. The difference produced by 



Table XXXVII. — Mean Annual Temperatures of Air and Water for Loch Fyne. 



Year. 



I. Air (mean 

 for Area). 



II. Air 



(Calltou Mor.). 



III. Water. 

 Surface 5 

 fathoms. 



IV. Water. 



Mass. 



Difference 

 Air II. and 

 Water III. 



between 

 Air II. and 

 Water IV. 



1886 

 1887 

 1888 

 Mean. 



46-2 

 47-0 

 46-7 

 46-63 



45-5 

 46-9 

 46-6 

 46-33 



46-8 

 48-6 

 47-1 

 47-50 



45-8 

 47-o 

 46-0 

 46-43 



-i-3 

 -i'7 



-o-5 



-ri 7 



-°"3 

 -o-6 

 + o-6 



- O'lO 



isolation comes out on comparing the excess of warmth of the mass of water in each 

 division over that of the air. On the average of 1886 and 1887, this factor for the 

 Channel, Arran Basin, and Loch Fyne was l° - 7, 0°"35, o, 45. Here the great depth of 

 the Arran Basin, and the uncertainty as to the true air and water mean temperatures, 

 prevent us from accepting its figure as of equal value with the other two. 



The Gareloch. 



This division is defined as the area lying north and west of Eow Point. It is five 

 miles long, and less than one mile wide at the widest. Outside Row Point a wide and 

 comparatively shallow basin communicates directly with the Estuary. The tides run 

 strongly into and out of the loch. The configuration of the loch is described in Part I. 

 p. 646, and sections given in No. 17, Plate 9 of that instalment. The area is 4'23 

 square miles, with a land drainage of 12*40 square miles. The ratio of water to total 

 drainage-area is 1: 3*93, and is the largest ratio of any of the lochs. 



The Gareloch is characteristically shallow and flat-floored, with gently sloping banks, 

 forming a single basin with a clearly defined bar. Its mean axial depth is 18 fathoms, 

 and its average depth only 7 fathoms. The tidal rise is 9 feet. 



In the Gareloch the average percentage of pure sea-water was found to be 89*6 per 

 cent, by volume. It is the freshest of the divisions of the Area, and is situated in a land- 

 ward position, exposed to a considerable range of climatic conditions. It may be con- 

 sidered in this place as a fourth and distinct type, showing temperature changes quite 

 different from those of the Channel, Arran Basin, or Loch Fyne. 



Observations at Row I. — This station is situated outside the Gareloch, with Row 



