Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667
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              <s>
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              turn round, ſtaying there above, and moving along with the
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              urnal converſion. </s>
              <s>Now I tell him, that that ſame ball falling from
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              the concave unto the centre, will acquire a degree of velocity
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              much more than double the velocity of the diurnal motion of the
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              Lunar concave; and this I will make out by ſolid and not
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              tinent ſuppoſitions. </s>
              <s>You muſt know therefore that the grave
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              body falling and acquiring all the way new velocity according
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              to the proportion already mentioned, hath in any whatſoever
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              place of the line of its motion ſuch a degree of velocity, that if it
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              ſhould continue to move therewith, uniformly without farther
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              encreaſing it; in another time like to that of its deſcent, it would
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              paſſe a ſpace double to that paſſed in the line of the precedent
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              motion of deſcent. </s>
              <s>And thus for example, if that ball in coming
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              from the concave of the Moon to its centre hath ſpent three hours,
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              22 min.
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              prim.
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              and 4 ſeconds, I ſay, that being arrived at the
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              tre, it ſhall find it ſelf conſtituted in ſuch a degree of velocity, that
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              if with that, without farther encreaſing it, it ſhould continue to
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              move uniformly, it would in other 3 hours, 22 min.
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              prim.
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              and
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              4 ſeconds, paſſe double that ſpace, namely as much as the whole
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              diameter of the Lunar Orb; and becauſe from the Moons
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              cave to the centre are 196000 miles, which the ball paſſeth in 3
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              hours 22
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              prim.
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              min. </s>
              <s>and 4 ſeconds, therefore (according to what
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              hath been ſaid) the ball continuing to move with the velocity
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              which it is found to have in its arrival at the centre, it would
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              paſſe in other 3 hours 22 min. </s>
              <s>prim. </s>
              <s>and 4 ſeconds, a ſpace
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              ble to that, namely 392000 miles; but the ſame continuing in
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              the concave of the Moon, which is in circuit 1232000 miles, and
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              moving therewith in a diurnal motion, it would make in the ſame
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              time, that is in 3 hours 22 min. </s>
              <s>prim. </s>
              <s>and 4 ſeconds, 172880
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              miles, which are fewer by many than the half of the 392000
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              miles. </s>
              <s>You ſee then that the motion in the concave is not as the
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              modern Author ſaith, that is, of a velocity impoſſible for the
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              ing ball to partake of,
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              &c.
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              The falling
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              able if it move with
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              a degree of
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              ty acquired in a
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              like time with an
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              uniform motion, it
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              ſhall paß a ſpace
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              double to that
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              ſed with the
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              leratedmotion.
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              <s>SAGR. </s>
              <s>The diſcourſe would paſs for current, and would give
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              me full ſatisfaction, if that particular was but ſalved, of the
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              ving of the moveable by a double ſpace to that paſſed in falling
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              in another time equal to that of the deſcent, in caſe it doth continue
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              to move uniformly with the greateſt degree of velocity acquired
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              in deſcending. </s>
              <s>A propoſition which you alſo once before
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              ſed as true, but never demonſtrated.</s>
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              <s>SALV. </s>
              <s>This is one of the demonſtrations of
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              Our Friend,
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              and
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              you ſhall ſee it in due time; but for the preſent, I will with ſome
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              conjectures (not teach you any thing that is new, but) remember you
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              of a certain contrary opinion, and ſhew you, that it may haply ſo be.
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              </s>
              <s>A bullet of lead hanging in a long and fine thread faſtened to the </s>
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