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

List of thumbnails

< >
171
171 		172
172
173
173 		174
174
175
175 		176
176
177
177 		178
178
179
179 		180
180
< >
page |< < of 701 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="040/01/175.jpg" pagenum="157"/>
              ball ſuſpend it ſelf in its range directly over the Piece. </s>
              <s>And in a
                <lb/>
              word, if you do but attentively conſider, you will comprehend,
                <lb/>
              that the motion of the Earth in transferring the Piece along with
                <lb/>
              it from C A to E D, conferreth upon the tranſverſe line C D, ſo
                <lb/>
              much of little or great inclination, as is required to adjuſt the
                <lb/>
              range to its perpendicularity. </s>
              <s>But you err, ſecondly, in that you
                <lb/>
              referr the faculty of carrying the ball along with the Earth to the
                <lb/>
              impulſe of the fire, and you run into the ſame error, into which
                <lb/>
                <emph type="italics"/>
              Salviatus,
                <emph.end type="italics"/>
              but even now ſeemed to have fallen; for the faculty
                <lb/>
              of following the motion of the Earth, is the primary and perpetual
                <lb/>
              motion, indelibly and inſeparably imparted to the ſaid ball, as to a
                <lb/>
              thing terreſtrial, and that of its own nature doth and ever ſhall
                <lb/>
              poſſeſs the ſame.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>Let us yield,
                <emph type="italics"/>
              Simplicius,
                <emph.end type="italics"/>
              for the buſineſs is juſt as he
                <lb/>
                <arrow.to.target n="marg347"/>
                <lb/>
              ſaith. </s>
              <s>And now from this diſcourſe let us come to underſtand the
                <lb/>
              reaſon of a Venatorian Problem, of thoſe Fowlers who with their
                <lb/>
              guns ſhoot a bird flying; and becauſe I did imagine, that in regard
                <lb/>
              the bird flieth a great pace, therefore they ſhould aim their ſhot far
                <lb/>
              from the bird, anticipating its flight for a certain ſpace, and more
                <lb/>
              or leſs according to its velocity and the diſtance of the bird, that
                <lb/>
              ſo the bullet haſting directly to the mark aimed at, it might come
                <lb/>
              to arrive at the ſelf ſame time in the ſame point with its motion,
                <lb/>
              and the bird with its flight, and by that means one to encounter
                <lb/>
              the other: and asking one of them, if their practiſe was not ſo
                <lb/>
              to do; He told me, no; but that the ſlight was very eaſie and
                <lb/>
              certain, and that they took aim juſt in the ſame manner as if they
                <lb/>
              had ſhot at a bird that did ſit ſtill; that is, they made the flying
                <lb/>
              bird their mark, and by moving their fowling-piece they followed
                <lb/>
              her, keeping their aim ſtill full upon her, till ſuch time as they let
                <lb/>
              fly, and in this manner ſhot her as they did others ſitting ſtill. </s>
              <s>It is
                <lb/>
              neceſſary therefore that that motion, though ſlow, which the
                <lb/>
              ing-piece maketh in turning and following after the flight of the
                <lb/>
              bird do communicate it ſelf to the bullet alſo, and that it be joyned
                <lb/>
              with that of the fire; ſo that the ball hath from the fire the
                <lb/>
              tion directly upwards, and from the concave Cylinder of the barrel
                <lb/>
              the declination according to the flight of the Bird, juſt as was ſaid
                <lb/>
              before of the ſhot of a Canon; where the ball receiveth from the
                <lb/>
              fire a virtue of mounting upwards towards the Zenith, and from
                <lb/>
              the motion of the Earth its winding towards the Eaſt, and of both
                <lb/>
              maketh a compound motion that followeth the courſe of the
                <lb/>
              Earth, and that to the beholder ſeemeth onely to go directly
                <lb/>
              wards, and return again downwards by the ſame line. </s>
              <s>The
                <lb/>
              ing therefore of the gun continually directed towards the mark,
                <lb/>
              maketh the ſhoot hit right, and that you may keep your gun
                <lb/>
              rected to the mark, in caſe the mark ſtands ſtill, you muſt alſo hold </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum