Binary Engine
usually an engine having one cylinder, the piston being impelled by steam, which, having done its work there, is exhausted into another part of the apparatus, where it is allowed to communicate its unutilized heat to some liquid volatile at a lower temperature; the vapor of this second liquid, by its expansion in a second cylinder, yields additional useful force. Ether, chloro- BINGEN form, and bisulphide of carbon have all been tried.