An essay on the draught of fire in furnaces, flues, and chimnies, and of the true causes, process, and effects thereof: Being an Intent to explain the Fundaments of the brief Account of a New Invention: For which has been obtained his Majesty's Royal Letters Patent. It consists of a peculiar method of constructing, and setting Boilers of any dimension in Fire-Engines, Salt-Works, Brewhouses, Distilleries, Sugar-Houses, and Sugar-Works abroad; and also in Allum, Copperas, Roman-Vitriol, Saltpetre-Works and Refineries thereof; in such a well contrived manner, that more than the half-part of coals and fuel may be saved, and yet a quicker and larger dispatch of business in every respect obtained. With some Remarks about common Salt and its Use. Published by the patentee, Christopher Chrysel.