An account of a useful discovery to distill double the usual quantity of sea-water, by blowing showers of air up through the distilling liquor, and also to have the distilled water perfectly fresh and good by means of a little chalk : and an account of the great benefit of ventilators in many instances, in preserving the health and lives of people, in slave and other transport ships ... : also an account of the good effect of blowing showers of air up through milk, thereby to cure the ill taste which is occasioned by some kinds of food of cows /