5. Then, filling the Still as full of Water as before, and when it began to boil, fixing the Head to the Still and Worm-tub, which was full of cold Water; there was distilled in an Hour, with constantly blowing Showers of fresh Air up thro’ the stilling Liquors, five Quarts, less by seven cubick Inches, which is 345.5ths cubick Inches; that is, little less than the double of the Quantity that is distilled in the usual Way. In several other Distillations of a Quart at a Time, I found the Quantity distilled by Ventilation, to be more than the double of that in the usual Way. So that the Quantity by Ventilation, may at a Medium be estimated the double of the usual Distillation. It is the well known Property of moving Air, to carry along with it a considerable Quantity of adjoining Vapour, as also of falling Water to carry much Air down along with it. 6. It is to be hoped therefore, that so considerable an Increase in the Quantity distilled, will be of great Benefit to Navigation, as it may be done in less Time and with less Fire. 7. In the Account of Mr. _Appleby_’s Process, for making Sea-water fresh, which is published by Order of the Lords of the Admiralty in the Gazette of _Jan. 22, 1754_, it is said that a Still which contains 20 Gallons of Water will distill 60 Gallons in ten Hours with little more than one Bushel of Coals; and therefore 120 Gallons in 20 Hours, with little more than two Bushels of Coals. And by Ventilation 240 Gallons, or a Tun; and 24 Gallons may be distilled in twenty Hours, making an Allowance for the times of heating those Stills full of cold Water; and a Still something larger and wider, will distill a Tun in 24 Hours; which will more than suffice for a sixty Gun Ship with 400 Men, whose Provision of Water for four Months is about 110 Tuns. And larger Ships may either have proportionably larger Stills, or else two of them. As for Merchant-Ships with few Men, a small Still will be sufficient. 8. The second sized Stills contain 10 Gallons, and will produce 60 Gallons in 20 Hours, with half the above-mentioned Fuel; and by Ventilation 120 Gallons. 9. The least Stills contain five Gallons, and will produce 32 Gallons in 20 Hours; and by Ventilation 64 Gallons in 20 Hours. 10. I have seen some of these Stills at Messrs. _Steel_ and _Stephens_, over-against _Mercers-Chapel_, in _Cheapside_, which have been made for this Purpose. There are Holes in the Feet of the Iron Frame or Stove to skrew them down to the Deck. They were fixed at the Fore-castle before the Mast in King _Charles_ the Second’s time, when they thought they had discovered the Way to distill Sea-water, free from the noxious Spirit of Salt, and from the nauseous bittern Taste. Or, if it be thought proper, one Part of the Ship’s Boiler may be made use of, by adapting a Still-head to it.