SEA-FISHERIES LABORATORY. LAT 
obvious that a warm wind (S. to W.) blowing steadily for 
a day or two must warm the surface of the sea, and, con- 
versely, that a cold wind (N.W., N., N.E., or E.) would 
also chill the surface water. But the wind would only 
affect an exceedingly thin superficial layer of sea-water, 
and this would be drifted along in the direction towards 
which the wind was blowing. In a tideless water-basin, 
such as a lake, the effect of this would be that warmer or 
colder water would be piled up along the coast towards 
which the wind was blowing while a deep counter-current, 
flowing in the opposite direction, would be set up. In 
this way the well-known stratification observed in 
enclosed lakes and in some sea lochs on the West Coast 
of Scotland, 1s produced. ‘The same effects ought to be 
produced in the Irish Sea, but, as a matter of fact, the 
temperature stratification is not observed; and the effect 
of a spell of cold or warm wind is simply to produce a 
homothermic water mass. Our experience in studying 
the temperature of the sea seems to be that the latter 
varies according to the prevalent wind. Yet when we 
try to express this relationship, by comparing curves 
showing the direction of the winds, and the temperature 
variations, from day to day, no correspondence between 
the two series of changes can be detected. 
But, when we compare the small temperature changes 
with tidal changes, a direct relationship is at once 
apparent. The Hastern part of the Irish Sea is a shallow- 
water basin, and one may say that all the water within the 
twenty-fathom line, that is Liverpool Bay and practically 
all the sea lying between the Isle of Man and the Lanca- 
shire and Cumberland coasts, and the sea within an 
average distance of 6} miles to the West, and 33 miles to 
the South of the Isle of Man, is coastal water. All along 
the West Coast of England, between Anglesey and the 
