BOTTOM, in navigation, is used to denote as well the channel of rivers and harbours, as the body or hull of a ship: Thus, in the former sense, we say, a gravelly bottom, clayey bottom, sandy bottom, &c. and in the latter sense, a British bottom, a Dutch bottom, &c.
By statute, certain commodities imported in foreign bottoms pay a duty called petty customs, over and above what they are liable to if imported in British bottoms.