CHAPTER XII.
STEAM NAVIGATION.
Propulsion by paddle-wheels. -- Manner of driving them. -- Marine Engine. -- Its form and arrangement. -- Proportion of its cylinder. -- Injury to boilers by deposites and incrustation. -- Not effectually removed by blowing out. -- Mr. Samuel Hall's condenser. -- Its advantages. -- Originally suggested by Watt. -- Hall's _steam saver_. -- Howard's vapour engine. -- Morgan's paddle-wheels. -- Limits of steam navigation. -- Proportion of tonnage to power. -- Average speed. -- Consumption of fuel. -- Iron Steamers. -- American steam raft. -- Steam navigation to India. -- By Egypt and the Red Sea to Bombay. -- By same route to Calcutta. -- By Syria and the Euphrates to Bombay. -- Steam communication with the United States from the west coast of Ireland to St. Johns, Halifax, and New York. 241