Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. Heat engines using the Brayton cycle and having a combustion chamber with internal combustion, but using a motor similar to an ordinary steam engine, instead of a turbine Wheel as in our case, have been built or planned in a multitude of forms, and the type of combustion chamber proposed for any one of these is of course suitable for the gas turbine. The relation of these engines to the gas turbine we shall discuss more fully in Chap. 2.