of the Fishery Board for Scotland. 



271 



far, we may state the general results of the work on Loch Fyne in 1896 as 

 follows : — 



The flood-tide brings in water from the upper and deeper layers of the 

 Arran Basin, which is thoroughly mixed in passing Otter Spit before high- 

 water, and fills the Gortans Basin with a nearly homothermic mass, which 

 is passed on through Minard Narrows into the Upper Basin, where it does 

 not sink through the cold deep water in summer, but only mixes with the 

 upper layers above 20 fathoms, becoming more superficial in its effects as 

 the tide passes upwards. In the ebb there is, at the upper end of the 

 loch, only a superficial movement, but at the platform between Furnace 

 and Minard, the rush of the surface current into the Gortans Basin while 

 it is strongest at half-ebb, draws up the deep cold layers to a slight extent, 

 causing a slight mixture with the warmer water. The homothermic mass 

 pours out into the Arran Basin, acting on the ebb probably in the same 

 way as at Furnace on the flood. Thus, there is always in progress a gentle 

 mingling of the deep waters of the two deep basins through the inter- 

 mediate shallow basin. The rapid surface current of the ebb carries out 

 the excess of fresh water from the Arran Basin, while the small under- 

 flow from the Arran Basin passes in water of higher salinity with the 

 flood. This circulation is liable to be accelerated or checked by the 

 influence of wind. 



The conclusions thus confirm the general view of the circulation of 

 Loch Fyne which I had previously put forward ; but farther observations 

 would be necessary to ascertain the exact process by which this circula- 

 tion is effected, and in particular to determine the relative parts taken by 

 wind and tide. 



