and finds the Scurvy begin to attack her. In order to which, it will be necessary to say something concerning the Nature of that Element called the Air.
Air is an elastic Fluid, as has been observed before, and is subject to an easy Motion of it's Parts amongst themselves, as all Fluids are. It is subject to Currents and Eddies, in the same Manner as Water. A Current of Air is commonly known by the Name of Wind; and the greater Quantity of this Air or Wind, an Animal who has Organs for the Reception of it, and who cannot live without it a Moment; the more free Passage (I say) a Current of Air has, by such an Animal, in Health and Motion, the more wholesome it is for him. Now, I will endeavour to prove, that a Ship under Sail, before a Trade Wind, has but little Change of Situation in this Current, notwithstanding her Motion is so swift, with regard to her Change of Place upon the Surface of the Earth.
We will endeavour to explain our Meaning, by a Cork swimming down a current of Water.
If any one throws a Cork into a Stream of Water, he will find that the Cork will be attended, during its Progress down the Stream, by the same Particles of the Fluid, which it happened to fall upon, when it first set off; notwithstanding, it changes its Position, with regard to the Surface of the Earth. This is the Case with a Ship, sailing before the Wind; she receives nothing near the Quantity of Air, upon her Sides and between her Decks, in a full Wind, that she does when the Wind is upon her Beam, or on one Side of her; which may be demonstrated by a second Experiment upon the Cork in the Water.
If any one takes a Cork and ties a long Thread to it, and throws it into a Stream, he will find, that the Cork, when he draws it sideways along the Stream, changes its Place in the Water every Inch he draws it. This is so plain, that there is no Occasion
to say any more about it; and we humbly apprehend, that the Case would be the same, with regard to a Ship which is sailing before the Wind, or going down a Current of Air. We do alledge, that the fresh Air running between the Decks of a Ship, would sweeten and clear away the bad Vapours and Filth from the Men in her, as much more in the Position of a Side-Wind, as a Stream of Water would wash more Dirt off a Cork, if it was drawn sideways along it by a Thread, than if it was suffered to swim down by itself. For the Motion of a good Ship, when she has all her Sails up in a moderate Gale before the Wind, is very near, if not quite as swift as the Wind itself.
Therefore, what I would advance here is, that as the Sea Scurvy in long Voyages proceeds as much from the Confinement of a Ship, as from any other Cause, may it not be deemed reasonable, that any Scheme, which serves to make a more free Current of Air through a Ship, may be
a great Hindrance to the Progress of the Scurvy?
The Scheme is only this plain and easy one, viz. that when a Ship is upon a long Voyage, before a Trade Wind, the Captain once a Day should give Orders, to lay her upon a Side-Wind, or a Quarters Wind, if he thinks it more safe, for about a League or two, during which Tack, he may open the Port-holes of her Windward Side; and after going a League or two in that Manner, she might be tacked about and laid upon her other Side; and by doing this, he would sweeten every Corner of the Ship, and at the same Time exercise his Men. Now, though this Practice would retard him a little in his Voyage, would it not be better to lose a little Time, and bring a Ship's Crew Home in tolerable good Plight, than to have half of them dead, before they get to the End of their Voyage? I am far from insisting, that this Scheme would answer the End; all that I know is, that if I was Captain of a Ship, I would try; and if it answered no End,