86 Canadian Record of Science. 
size; and the climate of the Queen Charlotte Islands is 
cooler and more rainy than that of Vancouver, whose 
northern end, in turn, is less pleasant than its southern part. 
Between the western, or oceanic, border of Vancouver 
Island, and the mainland coast, there is considerable dif 
ference, in favor of increased dryness and greater thermo- 
metrical range. That is, it becomes colder in mid-winter, 
and hotter in mid-summer than on the outer coast of the 
island. But the extreme in neither season is a hardship, 
and, on the whole, New Westminster and the new city of 
Vancouver have an even more agreeable climate than Vic- 
toria. People wear the same clothes the year round, and 
an umbrella must be a pretty constant part of one’s outfit, 
except during the long and beautiful autumn, which is like 
a far-extended Indian summer. 
The explanation of this climate has already been hinted 
at. The water of the Pacific is warm—20 degrees warmer 
than that of the North Atlantic near Canadian shores. 
The prevailing south-westerly winds, sweeping over its 
surface, are raised to the temperature of the water, and 
become saturated with moisture, abstracting from it, and 
rendering “latent,” in conformity with well-known physical 
laws, a still greater quantity of heat. Wh n, on reaching 
the mountainous coast, this moisture is condensed and dis- 
charged, the latent heat becomes again apparent, and 
greatly raises the temperature of the atmosphere in which 
the reaction occurs. fence the coast climate of the whole 
north-west coast of North America is warm. The mean 
annual temperature of Sitka is nearly the same as that of 
Montreal. 
That the climate is wet as well as warm, is owing to the 
effect of the height of the coasts. The heaviest rainfall 
occurs in exact correspondence with the height to which 
the moist air is forced into the higher regions of the atmos- 
phere, and cooled there by its expansion and loss of heat 
by radiation. In proportion to the elevation of the islands, 
and the degrees in which they shelter the mainland coast 
from the rain-bearing winds, the rain fall on the opposite coast 
