Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667
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              all converſion from the Annual motion, could be made, one
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              while in a greater, and another while in a leſſer proportion;
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              which diverſity, and no other thing, could be aſſigned for the
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              cauſe of the alterations, Monethly and Annual, that are ſeen in
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              the greatneſſe of the Ebbings and Flowings. </s>
              <s>I will now
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              ſider how this proportion of the additions and ſubſtractions of
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              the Diurnal Revolution, and Annual motion may grow greater
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              and leſſer three ſeveral wayes. </s>
              <s>One is by increaſing and
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              niſhing the velocity of the Annual motion, retaining the
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              ons and ſubſtractions made by the Diurnal converſion in the
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              ſame greatneſſe, becauſe the Annual motion being about three
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              times greater, that is, more velocious than the Diurnal motion
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              (conſidered likewiſe in the Grand Circle) if we increaſe it
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              anew, the additions and ſubſtractions of the Diurnal motion
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              will occaſion leſſe alteration therein: but, on the other ſide,
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              making it more ſlow, it will be altered in greater proportion, by
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              that ſame diurnal motion, juſt as the adding or ſubſtracting
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              four degrees of velocity from one that moveth with twenty
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              grees, altereth his courſe leſſe, than thoſe very four degrees would
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              do, added or ſubſtracted from one that ſhould move onely with
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              ten degrees. </s>
              <s>The ſecond way would be, by making the
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              ons and ſubſtractions greater and leſſer, retaining the annual
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              tion in the ſame velocity; which is as eaſie to be underſtood, as it
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              is manifeſt, that a velocity
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              v. </s>
              <s>gr.
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              of 20. degr. </s>
              <s>is more altered by the
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              addition or ſubſtraction of 10. deg. </s>
              <s>than by the addition or
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              ction of 4. The third way would be, in caſe theſe two were joyned
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              together, diminiſhing the annual motion, & increaſing the diurnal
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              additions and ſubſtractions. </s>
              <s>Hitherto, as you ſee, it was no
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              hard matter to attain, but yet it proved to me very hard to find
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              by what means this might be effected in Nature. </s>
              <s>Yet in the end,
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              I finde that ſhe doth admirably make uſe thereof, and in wayes
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              almoſt incredible: I mean, admirable and incredible to us, but
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              not to her, who worketh even thoſe very things, which, to our
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              capacity, are of infinite wonder, with extraordinary facility and
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              ſimplicity: and that which it is hard for us to underſtand, is
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              ſie for her to effect. </s>
              <s>Now to proceed, having ſhewn that the
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              proportion between the additions and ſubſtractions of the
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              nal converſion and Annual motion may be made greater and
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              ſer, two wayes, (and I ſay two, becauſe the third is comprized in
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              the two firſt) I adde, that Nature maketh uſe of them both:
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              and farthermore, I ſubjoyn, that if ſhe did make uſe but of one
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              alone, it would be neceſſary to take away one of the two
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              dical alterations. </s>
              <s>That of the Monethly Period would ceaſe, if
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              the annual motion ſhould not alter. </s>
              <s>And in caſe the additions
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              and ſubſtractions of the diurnal revolution ſhould continually </s>
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