24.8 THE LIFE OF

perused the latter part of the Letter, it will appear to you, he might havedone better to have left it out, since the Parallaxes of the fixed Stars are de-termined without moving these Poles at all; and making them to move mis-represents the Parallaxes: so that on the whole, you will conclude that heunderstood nothing of the Business. -— This I mind you of, because I have notmentioned it in the Letter, which I have wrote after my usual Way with allthe Plainness and Sincerity imaginable, and so as not to give Monsi Cajjini , orany other any Offence, or Cause to complain of uncivil Usage. It is some-thing longer than I designed at first it stiould be; being a new Subject, anduncommon, I thought it was better to err on this Hand, than to make itobscure by my Brevity.

John Flamstead.

SIR,

I Send you here some Reflections on Mons. Cajjini § Remarks on my Letter toDr. Wallis, together with an Account of the Effects of the Earth’s Motionin changing the Longitudes, Latitudes, Right Ascensions and Declinations ofthe fixed Stars. ’Tis a new Subject, and never that I know of handled before.For though Mr. Cajjini proposes to himself to examine what will be the Rej'ult ojthe Hypothesis of the Earth's Motion, with refpeSl of the fixed Stars and theapparent Poles of the Earth and the Ecliptick, in order to prove that the greatestRemove of the Pole-star from the Pole, is made about the Beginning of theforeign April, and its nearest Approach of OSlober ; yet he has done it in sucha Manner as will make it appear to you, that though there be some Truth r?rshe Conclusion, yet it does not result from his Premises (as I asserted) or any deepConsideration of the Effects of the Earth’s Motions, or geometrical Argu-mentation.

His first Figure represents mine well enough, and his Report of the Con-tents of my Letter is fair and candid ; but the Ground of his Error is laid inhis second, where with me making IODR to represent the Earth’s Orbit, heraises Perpendiculars from every Point of it ’till they intersect the Plane EQ>(supposed placed on the Surface of the Sphere parallel to the Plane of theEcliptick) whereby they describe on it the Orbit EML which will thereforebe an exact Representative of the Orbit DOIR; now this, all that allow theMotion of the Earth make an Ellipsis, therefore that must be an Ellipsis too,and the Point M in this will represent the Sun, or the Point S in the originalOrbit DOIR; though in his 3d Fig. he makes and calls it a Circle whereina moveable Pole of the Ecliptick is carried annually about a fixed and di-vides it into twelve Signs marked with their proper Characters: Again,Drawing Lines parallel to the Earth’s Axis to every Point of the originalOrbit DOIR, till they intersect the aforesaid Plane EQ, he projects anotherCurve NPQ^ which also shall be an Ellipsis (but more oblique than theformer) and a distinct Representative of the Earth’s Orbit the Sun’s Place init being at P, in the Line SP, drawn from the Sun 8 in the original Parallelto the Axis.

Yet in his 3d Fig. he makes and calls it a Circle in which a moveable Poleof the World revolves annually about a fixed one, and this also he distin-guishes with the twelve Signs, as he had done the other.

Near this last representative Orbit he lays of a Star at V, which he &y sshall be sometimes nearer, at other, farther off from the Pole of the World-He shews no Reason why this Star’s Place may not be laid off with the saru^respect to the other distinct representative Orbit EML and to the originIODR : Let it be done for the first at V for the Original at Y, it appears no^

that as the Earth makes her annual Revolution, she sometimes comes nearest

to

“ II sera a" propos tCex-" aminer ce" qui refulte“ de CHypo-“ these du“ mouvement“ de la terre,“ par rapport“ aux etoiles“ fixes, £ 3 ’

“ aux poles“ apparent de“ laterreetde“ secliptique.

Caffini’j idFig.