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

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              <s>
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              the Moon and Sun; neer, in a word, at the time of its conjun
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              ction and change; remote, in its Full and Oppoſition; and the
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              greateſt vicinity differ the quantity of the Diameter of the
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              nar Orb. </s>
              <s>Now if it be true that the virtue which moveth the
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              Earth and Moon, about the Sun, be alwayes maintained in
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              the ſame vigour; and if it be true that the ſame moveable
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              moved by the ſame virtue, but in circles unequal, do in ſhorter
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              times paſſe like arches of leſſer circles, it muſt needs be granted,
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              that the Moon when it is at a leſſe diſtance from the Sun, that is
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              in the time of conjunction, paſſeth greater arches of the Grand
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              Orb, than when it is at a greater diſtance, that is in its Opppſition
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              and Full. </s>
              <s>And this Lunar inequality muſt of neceſſity be imparted
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              to the Earth alſo; for if we ſhall ſuppoſe a right line produced from
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              the centre of the Sun by the centre of the Terreſtrial Globe, and
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              prolonged as far as the Orb of the Moon, this ſhall be the
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              diameter of the Grand Orb, in which the Earth, in caſe it were
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              alone, would move uniformly, but if in the ſame ſemidiameter we
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              ſhould place another body to be carried about, placing it one
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              while between the Earth and Sun, and another while beyond
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              the Earth, at a greater diſtance from the Sun, it is neceſſary,
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              that in this ſecond caſe the motion common to both, according
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              to the circumference of the great Orb by means of the diſtance
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              of the Moon, do prove a little ſlower than in the other caſe,
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              when the Moon is between the Earth and Sun, that is at a leſſer
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              diſtance. </s>
              <s>So that in this buſineſſe the very ſame happeneth that
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              befals in the time of the clock; that lead which is placed one
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              while farther ſrom the centre, to make the vibrations of the
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              ſtaffe or ballance leſſe frequent, and another while nearer, to
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              make them thicker, repreſenting the Moon. </s>
              <s>Hence it may be
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              manifeſt, that the annual motion of the Earth in the Grand
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              Orb, and under the Ecliptick, is not uniform, and that its
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              regularity proceedeth from the Moon, and hath its Monethly
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              Periods and Returns. </s>
              <s>And becauſe it hath been concluded, that
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              the Monethly and Annual Periodick alterations of the ebbings
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              and flowings, cannot be deduced from any other cauſe than
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              from the altered proportion between the annual motion and the
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              additions and ſubſtractions of the diurnal converſion; and that
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              thoſe alterations might be made two wayes, that is by altering
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              the annual motion, keeping the quantity of the additions
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              altered, or by changing of the bigneſſe of theſe, reteining the
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              uniformity of annual motion. </s>
              <s>We have already found the firſt
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              of theſe, depending on the irregularity of the annual motion
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              occaſioned by the Moon, and which hath its Monethly Periods.
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              </s>
              <s>It is therefore neceſſary, that upon that account the ebbings
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              and flowings have a Monethly Period in which they do grow </s>
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