Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/431

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G. Galilæus, his Systeme.

same terrestrial evaporations,Constant gales within the Tropicks blow towards the West. we finde a perpetual gale move from the East with so constant a blast, that ships by favour thereof sail prosperously to the West-India's. And from the same coasting along the Mexican shore, they with the same felicity pass the Pacifick Ocean towards the India's; which to us are East, but to them are West.The course to the West-India's easie, the return difficult. Whereas on the contrary the Course from thence towards the East is difficult and uncertain, and not to be made by the same Rhumb, but must vere more to Land-ward, to recover other Winds, which we may call accidentary and tumultuary, produced from other Principles, as those that inhabit the continent find by experience. Of which productions of Winds, the Causes are many and different, which shall not at this time be mentioned.Winds from Land make rough the Seas. And these accidentary Winds are those which blow indifferently from all parts of the Earth, and make rough the Seas remote from the Equinoctial, and environed by the rugged Surface of the Earth; which is as much as to say environ'd with those perturbations of Air, that confound that primary Gale. The which, in case these accidental impediments were removed, would be continually felt, and especially upon the Sea. Now see how the effect of the Water and Air seem wonderfully to accord with the Celestial observations, to confirm the mobility of our Terrestrial Globe.

Sagr.I also for a final close will relate to you one particular,Another observation taken from the Air in confirmation of the motion of the Earth. which as I believe is unknown unto you, and which likewise may serve to confirm the same conclusion: You Salviatus alledged, That Accident which Sailers meet with between the Tropicks; I mean that perpetual Gale of Winde that beats upon them from the East, of which I have an account from those that have many times made the Voyage: And moreover (which is very observable) I understand that the Mariners do not call it a Wind, but by another ** Which Wind with our English Mariners is called the Trade-wind. name, which I do not now remember, taken haply from its so fixed and constant Tenor; which when they have met with, they tie up their shrouds and other cordage belonging to the Sails, and without any more need of touching them, though they be in a sleep, they can continue their course. Now this constant Trade-wind was known to be such by its continual blowing without interruptions; for if it were interrupted by other Windes, it would not have been acknowledged for a singular Effect, and different from the rest: from which I will infer, That it may be that also our Mediterranean Sea doth partake of the like accident; but it is not observed, as being frequently altered by the confluence of other windes. And this I say, not without good grounds, yea upon very probable conjectures whch came unto my knowledge, from that which tendred it self to my notice on occasion of the voyage that I made into Syria, going Consul for this Nation

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