Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667

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              <s>
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              the Axis of the grand Orb, the Earths centre being in the
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              tial point of Capricorn. </s>
              <s>Suppoſing therefore the Terreſtrial
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              Globe to have its centre in the point Capricorn, we will deſcribe
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              its Poles and Axis A B, inclined upon the diameter Capricorn
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              Cancer 23 degrees and an half; ſo that the angle A Capricorn
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              Cancer cometh to be the complement of a Quadrant or Radius,
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              that is, 66 degrees and an half; and this inclination muſt be
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              derſtood to be immutable, and we will ſuppoſe the ſuperiour
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              Pole A to be Boreal, or North, and the other Auſtral, or South.
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              </s>
              <s>Now imagining the Earth to revolve in it ſelf about the Axis A B
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              in twenty four hours, from Weſt to Eaſt, there ſhall by all the
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              points aſſigned in its ſuperſicies, be circles deſcribed parallel to
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              each other. </s>
              <s>We will draw, in this firſt poſition of the Earth,
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              the greateſt C D, and thoſe two diſtant from it
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              gr.
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              23. and an
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              half, E F above, and G M beneath, and the other two extream
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              ones I K and L M remote, by thoſe intervals from the Poles A
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              and B; and as we have marked theſe five, ſo we may imagine
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              numerable others, parallel to theſe, deſcribed by the
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              ble points of the Terreſtrial ſurface. </s>
              <s>Next let us ſuppoſe the
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              Earth, with the annual motion of its centre, to transferre it ſelf
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              into the other places already marked; but to paſſe thither in ſuch
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              a manner, that its own Axis A B ſhall not only not change
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              nation upon the plain of the Ecliptick, but ſhall alſo never vary
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              direction; ſo that alwayes keeping parallel to it ſelf, it may
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              continually tend towards the ſame part of the Univerſe, or, if
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              you will, of the Firmament, whereas, if we do but ſuppoſe it
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              prolonged, it will, with its extream termes, deſigne a Circle
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              rallel and equal to the grand Orb, Libra Capricorn Aries Cancer,
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              as the ſuperiour baſe of a Cylinder deſcribed by it ſelf in the
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              nual motion above the inferiour baſe, Libra Capricorn Aries
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              Cancer. </s>
              <s>And therefore this immutability of inclination
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              nuing, we will deſign theſe other three figures about the centres
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              Aries, Cancer, and Libra, alike in every thing to that firſt
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              ſcribed about the centre Capricorn. </s>
              <s>Now we will conſider the
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              firſt figure of the Earth, in which, in regard the Axis A B is
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              clined from perpendicularity upon the diameter Capricorn
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              cer 23 degrees and an half towards the Sun O, and the arch A I
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              being alſo 23 degrees and an half, the illumination of the Sun
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              will illuſtrate the Hemiſphere of the Terreſtrial Globe expoſed
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              towards the Sun (of which, in this place, half is to be ſeen)
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              vided from the obſcure part by the Terminator of the light
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              I M, by which the parallel C D, as being a grand circle, ſhall
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              come to be divided into equal parts, but all the reſt into parts
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              equal; being that the terminator of the light I M paſſeth not
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              by their Poles A B, and the parallel I K, together with all the reſt </s>
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