Steam-engines 38 Steam engineering 27 History 13 Internal combustion engines 4 Boilers 3 Heat-engines 3 Steam engineers 3 Steam-boilers 3 Biography 2 Congresses 2 Marine engines 2 Mechanical engineering 2 Periodicals 2 Steam 2 Steam power plants 2 Technological chemistry 2 Traction-engines 2 Balancing of machinery 1 Building-service employees 1 Businessmen 1 Capitalism 1 Capitalists and financiers 1 Charts, diagrams, etc 1 Compressed air 1 Construction workers 1 Costs 1 Design and construction 1 Early works to 1850 1 Efficiency 1 Energy conservation 1