Silver fox is one of the most valuable of all furs, as much as £480 having been given for an unusually fine pair of skins in 1902.
It was devised by the Hudson's Bay Company for carrying freight, as a substitute for the less serviceable canoe, and was named after their York factory, the centre to which the traders brought down the furs for shipment to England and from which they took back merchandise and supplies to the interior of Rupert's Land.
The river is navigable for 770 m.; grain and a variety of goods conveyed from the upper Kama are floated down, while furs, fish and other products of the sea are shipped up the river to be transported to Cherdyn on the Kama.
The external trade of the Russian empire (bullion and the external trade of Finland not included) since the year 1886 is shown in the following table: The exports rank in the following order :- cereals (wheat, barley, rye, oats, maize, buckwheat) and flour, 49.2%; timber and wooden wares, 7.2; petroleum, 5.8; eggs, 5.4; flax, 5; butter, 3; sugar, 2-4; cottons and oilcake, 2 each; oleaginous seeds, &c., 1.5; with hemp, spirits, poultry, game, bristles, hair, furs, leather, manganese ore, wool, caviare, live-stock, gutta-percha, vegetables and fruit, and tobacco.
Place in corn and flour from the presence of the larvae of the Mediterranean flour moth (Ephestia kuniella); while furs and clothes are often ruined by the clothes moth (Tinea trapezella).