This Nisus, or resisting Motion to the Descent of Bodies, is not only perceptible in the Lead, but more sensibly declares itself, first, in that black or green Skim, seen sometimes on the Surface (even smelling) after long Calms, the Product of some intestine Motion.
2. That Divers, or any floating Bodies, emerge with greater Force than they sunk.
3. Mr. Boyle’s 20th Experiment observes, that a glass Bubble let open into the Receiver, on the Exsuction of the Air, the Water in it manifestly rises a greater Height; consequently the Expansion and Rarefaction of the Air by the Heat of the Sun, makes room for this Spring in the Water, to exert itself; and therefore the Tides themselves would more difficultly yield to the distant Attractions of the Sun and Moon (I should think) without adding to that Theory this conjoined Force, or natural Propensity of the Sea, to swell before.
In respect to sinking the Lead, also may be added, a greater Coldness, and a greater Saltness of the Sea, in proportion to the Depths; (both which are very probable,) and will create a greater Buoyancy, or Resistance to sinking, as will likewise the drawing out a greater Quantity of Line, (less apt to demerge.) So that although falling Bodies in Air, have their Velocities encreased, the nearer they approach the Earth, yet contrarily in Water, it diminishes with the Descent.
[39] Depend much on the preceding Season, (hot and dry Weather) apt to raise greater Plenty of elastick Vapours on the Terra firma, and will explode themselves now here, now there, as the greater Rarefaction of Air (more towards one Island than another) may invite.
BOOKS lately Printed for, and Sold by Cæsar Ward and Richard Chandler, at the Ship, between the Temple-Gates in Fleet-Street, and at their Shop in Scarborough.
1. A Voyage to Guinea, Brasil, and the West-Indies, in His Majesty’s Ships the Swallow and Weymouth. Describing the several Islands and Settlements, Madeira, the Canaries, Cape de Verd, Sierraleon, Sesthos, Cape Apollonia, Cabo Corso, and others on the Guinea Coast; Barbadoes, Jamaica, &c. in the West Indies. The Colour, Diet, Languages, Habits, Manners, Customs and Religions of the respective Natives, and Inhabitants. With Remarks on the Gold, Ivory, and Slave-Trade; and on the Winds Tides and Currents of the several Coasts. By John Atkins, Surgeon in the Royal Navy.
Illi Robur & Æs triplex
Circa Pectus erat qui fragilem truci