The Diesel engine has caused a great deal of comment of late years because of the spectacular uses to which it has been successfully applied. A specially constructed Diesel engine was probably the chief aid in the accomplishment of the first submarine trans-Atlantic voyage by the German submarine "Deutschland."

It is an oil engine which was invented by Rudolph Diesel in 1893.

The engine operates at compression pressures very much higher than those used in any other internal combustion engines, and it dispenses with the usual igniting devices by rendering the air charge incandescent by compression.

The Diesel Engine.

The efficiency of the Diesel engine is high, and it can use low grades of fuel, but it has the disadvantage of greater weight per horse-power than other engines.

It has found increasing favor for use in marine propulsion, and in 1913 was adapted to high-speed railway service, and put into use in Germany.