First edition: Hales' ventilators became known as "ship's lungs", and were so appreciated by eighteenth-century sailors, and contributed so significantly to an improvement in seaboard conditions, that captains reported the crews needed little encouragement to work the machines.

First edition: Hales' ventilators became known as "ship's lungs", and were so appreciated by eighteenth-century sailors, and contributed so significantly to an improvement in seaboard conditions, that captains reported the crews needed little encouragement to work the machines.

After a leisurely twelve years in residence at Cambridge, Hales (1677-1761) took up a parish and became heavily involved in local affairs, but this did not preclude him from a long and productive scientific career. His continuing fame was assured with these two books, which effectively invented artificial ventilation. Designed to draw fresh air into confined spaces, his machines were installed in His Majesty's ships, merchant vessels, slave ships, in hospitals, even at the court of King's Bench, the Drury Lane Theatre and Newgate Prison. As a result, there was a marked improvement in mortality rates, even among French prisoners-of-war held in English gaols, which led Hales to quip that he hoped none would accuse him of corresponding with the enemy.

He was a pioneer in public health, a role that he apparently considered a vocation: his friend Gilbert White commented that Hales could barely be restrained from offering unsolicited advice to friends and acquaintances, his wide-ranging mind capable of discoursing endlessly on the perils of encrusted tea-kettles or on the best methods of maintaining the keels of boats to passing ferrymen. White records one particularly endearing act of benevolence, commenting that he once spotted Hales busy painting white the 'tops of the foot-path posts, that his neighbours might not be injured by running against them in the dark' (DNB). Hales was elected a fellow of the Royal Society in 1718.

The second volume in this set, uniformly bound, was published in 1758, and details the various applications and improvements his ventilators had found in the intervening years.