ABSTRACT
The atmospheric or vacuum engine, no longer a marvel to the unlettered, neglected by men of science, and its practical construction relegated to the hands of mill-wrights, had gone on the even tenor of its way for years, unruffled by any event until 1765, when an invention was made that was destined to change its history. The invention was that of the separate condenser, the greatest single improvement ever made in the engine. The inventor was an obscure mathematical instrument-maker in Glasgow, named James Watt; what he did, to put it in a nutshell, was to effect the condensation of the steam, not in the cylinder itself, but in a vessel separate from it, thereby conserving most of the heat that had hitherto been thrown away by the alternate heating and cooling of the cylinder. A new era was thus inaugurated amounting almost to a rebirth of the engine.
