 Briefly, the system worked well and obtained a small increase in economy by decreasing fuel consumption, but at the price structure prevailing at that time the extra constructional and maintenance costs were greater than the coal economy.H.W.Dickinson's "A Short History of The Steam Engine" makes it clear that the concept of the uniflow engine reached back to Montgolfier and Jacob Perkins (who patented the idea) and Leonard Jennett Todd (Patent No.