The main trade of Salem is along the coast, principally in the transhipment of coal; and the historic Crowninshield's or India wharf is now a great coal pocket.
Sulina is the only free port on the Danube, and is much used for the transhipment into seagoing vessels of grain which is brought down the river in large lighters from Rumania, Russia, Bulgaria, Servia and AustriaHungary.
In 1900 the consignment of arms and ammunition to the Persian Gulf through Indian ports with or without transhipment was made illegal.
As a local centre of distribution this port is of no great consequence, the transhipment trade with Szech'uen being almost its sole business.
As none of these can be reached without transhipment in foreign territory, the cost of transport is increased, and her neighbours are enabled to exclude Bolivia from direct commercial intercourse with other nations.