294 CRUISE OF THE NEPTUNE 
as the slightest shock causes the mass to fall to pieces with a 
great commotion but with little danger. This disintegration is 
known as { calving.' 
The northern ice which occasionally enters Hudson strait in 
the early part of the winter as before described, is much more 
complicated and much heavier in character than the local ice. 
Some of this ice may be met with in the early period of naviga- 
tion to the eastward of Big island, and should be treated with 
respect. The icebergs included with it often remain until late 
in the season, and form a source of danger in foggy weather, 
but they are usually so few as to be negligible, especially in the 
western half of the strait. 
To summarize the foregoing : Hudson strait and Hudson bay 
do not freeze solid, but are so covered with masses of floating 
ice as to be practically unnavigable for at least seven months in 
the year. The ice does not begin to melt until well into the 
month of June, and is not sufficiently melted for safe navigation 
with ordinary steamers until the middle of July. No ice is 
formed in the strait and bay sufficiently heavy to obstruct 
ordinary navigation until the latter part of November, but 
towards the close of this period there is danger from the early 
passage of the northern pack across the mouth of the strait, and 
also, to a much less degree, from the ice from Fox channel 
partly closing the western entrance to the strait. 
When the temperature of the air falls several degrees below 
zero, as it does in November, a thick mist or fog rises from the 
open water and renders navigation somewhat dangerous. In 
the early part of the season before the ice has completely melted, 
fogs are liable to occur in proximity to the ice fields. At other 
times fogs are not prevalent, and the weather is ordinarily fair. 
The worst storms come from the south and east, and these are 
usually accompanied by rain in the summer, and by snow later 
in the season. Northerly winds bring clear cold weather as a rule. 
