A description of ventilators : whereby great quantities of fresh air may with ease be conveyed into mines, goals, hospitals, work-houses and ships, in exchange for their noxious air. An account also of their great usefulness in many other respects: as in preserving all sorts of grain dry, sweet, and free from being destroyed by weevels, both in grainaries and ships: and in preserving many other sorts of goods. As also in drying corn, malt, hops, gun-powder, &c. and for many other useful purposes. Which was read before the Royal Society in May 1741.
