Note 9 — Chapter XLV · THE LOWER AMUR.

A mile below the town there are sandbanks, and a bar which prevents the entrance of ships drawing more than 13 feet of water. In fact, from the Continent to the Island of Sakhalin are sandbanks, among which wind the navigable channels, which are liable to change during heavy tempests, so that the pilots are obliged to trace them, sounding-rod in hand. I heard, too, that for strategic purposes some of these channels at the mouth of the river could be filled up, or diverted.