navigation 295 
The period of safe navigation for ordinary iron steamships 
through Hudson strait and across Hudson bay to the port of 
Churchill, may be taken to extend from the 20th of July to the 
1st of November. This period might be increased without much 
risk by a week in the beginning of the season and by perhaps 
two weeks at the close. 
Ships entering Hudson strait from the Atlantic during the 
early part of the season, when ice is present in the strait, should 
keep in the northern half of the channel between resolution 
and the Button islands. Care should be taken to keep some 
miles from resolution, as the strong currents close to the island 
cause the ice to come together and open again with considerable 
violence. The north side of the strait should be followed as far 
as Big island, keeping at a respectful distance from the land in 
order to avoid the pressure when the ice is pressed on the land 
by southerly winds. There are frequently large quantities of 
ice in the neighbourhood of Big island, with at times consider- 
able pressure; on this account ships should not approach close to 
the island. From Big island the course should be so laid that 
the ship may pass a few miles to the northward of Charles 
island, and from there the middle channel should be followed to 
pass between Nottingham island and Cape Wolstenholme. The 
southern side of the channel between Mansfield and Coats is 
usually freer of ice than the north side. 
In passing eastward through Hudson strait, advantage should 
be taken of the favourable current on the south side, and that 
shore followed to Charles island, where the channel to the south 
of the island may be used, taking care to keep well away from 
the mainland until Cape Weggs is passed. The southern half 
of the centre channel should then be followed to beyond Big 
island, when the mid channel across the mouth of ungava bay 
will probably be found clear of ice. 
The fur trade with the Indians and Eskimos living about 
Hudson bay or along interior routes tributary to it, has for a 
