Page:Philosophical Transactions - Volume 003.djvu/28

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Africa to that of America, (which is also the Cause of the constant Eastern Brize blowing in those parts.) Butthe Sea thus beating on the Coast of America, is cast back as with an Eddy on either hand, and consequently returns from the American shore East-ward towards the Coast of Europe; where, the Parallel Circles to the Æquator being less, and consequently the Diurnal Motion slower, doth not cast the waters so strongly West-wards, as between the Tropicks, and so not strong enough to overcome the Eddy, which it meets with from the other Motion, which gives the Sea a North-Easterly Motion (on these Coasts) as to its usuall course. The Current therefore of our Seas being North-Easterly, we are next to consider, at what times it runs more to the North, and at what more to the East. When it runs most Northerly, it runs up the Irish Sea, and so up the Severn: When most Easterly, it runs streight up the Channel, and so to the Coast of Kent: When between these, it beats against Devonshire and Cornwall, and those parts. We are therefore to consider (as to the Annuall periods) that the Annuall Motion of the Earth in the Zodiack, and the Diurnal in the Æquator, are not precisely in the same direction, but make an Angle of 231/2 deg. at the Æquinoxes; but run, as it were, parallel at the Solstices: And as they be nearer, or further from these points, so is the Inclination varied. Which several directions of Motion, do cause the Compound Motion of both to vary from the East and West more or less, according as the Sun's Position is farther or nearer the Solstices, And therefore, nearer to the Æquinoxes, this Inclination doth cast the Constant current of out Seas more to the North and South; and further from it, more to the East and West, Which is the reason why the Current up the Irish Sea is nearer to the Æquinoxes (at the beginning of March and end of September) and up the Channel or Narrow Seas, farther from it (at the beginning of February and of November:) and against the Coasts of Devonshire and thereabout, at some intermediate time. And thus much I thought fit to signifie upon this occasion. Dat, Oxford the 7, of March An. 1667/8.

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