394 
Proceedings of the Royal Society 
Monday , 7 th May 1877. 
DAVID STE VENISON, Esq., Vice-President, in the 
Chair. 
The following Communications were read:— 
1. On new and little-known Fossil Fishes from the Edin- 
burgh District. No. III. By Dr B. H. Traquair. 
2. On Ocean Circulation. By John Aitken. 
It is with extreme reluctance that I venture to disturb the pre- 
sent repose of the much-contested field of ocean circulation. My 
object is not, however, to provoke discussion on the general theory 
of ocean circulation, as I am sure all will agree in thinking that 
the subject has already been discussed far beyond the point at 
which it is likely to be benefited by discussion. My object is 
simply to call attention to certain influences at work in the ocean, 
the effects of which seem to have been totally overlooked. 
The first of them to which I wish to refer is the influence of the 
winds on the ocean. The extreme holders of the wind theory of ocean 
circulation consider that the action of the wind is quite sufficient to 
account for all the currents which we find in the ocean. That the 
wind is a cause of ocean currents no one can doubt. If we 
examine a lake when the wind is blowing over it, we shall find 
that the plants growing in the shallow water near the surface are 
all bending in the direction of the wind, indicating that there is a 
current at the surface flowing in the direction of the wind, — the 
appearance of the bending plants in the lake reminding one of a 
slow-running river. To supply the water for this surface current 
there must, of course, be another current, flowing in the opposite 
direction underneath. The lake and the ocean are not, however, 
parallel cases. In the case of the lake, the wind is blowing in the 
same direction all over it, so that the return current is forced to 
flow underneath the surface, as it cannot get back any other way; 
whereas, in the ocean, the wind blows in one direction at one part, 
