Alberti, Leone Battista, Architecture, 1755

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              <s>
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              Pyramid of above ſix Furlongs high, raiſed a
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              Mound of Earth all the Way up along with
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              the Building, by which he carried up thoſe
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              huge Stones into their Places.
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              Herodotus
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              writes
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              that
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              Cheops,
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              the Son of
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              Rhampſinites,
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              in the
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              building of that Pyramid which employed an
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              hundred thouſand Men for many Years, left
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              Steps on the Outſide of it, by means of which
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              the largeſt Stones might by proper Engines, be
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              raiſed up into their Places without having Oc­
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              caſion for very long Timbers. </s>
              <s>We read too
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              of Architraves of vaſt Stones being laid upon
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              huge Columns in the following Manner: Un­
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              der the Middle of the Architrave they ſet two
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              Bearers acroſs, pretty near each other. </s>
              <s>Then
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              they loaded one End of the Architraves with a
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              great Number of Baskets full of Sand, the
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              Weight of which raiſed up the other End, on
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              which there were no Baskets, and one of the
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              Bearers was left without any Weight upon it:
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              Then removing the Baskets to the other End
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              ſo raiſed up, and putting under ſome higher
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              Bearers in the Room of that which was left
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              without Weight, the Stone by little and little
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              roſe up as it were of its own accord. </s>
              <s>Theſe
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              Things which we have here briefly collect­
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              ed together, we leave to be more clearly
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              learnt from the Authors themſelves. </s>
              <s>But
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              the Method of this Treatiſe requires, that we
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              ſhould ſpeak ſuccinctly of ſome few Things
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              that make to our Purpoſe. </s>
              <s>I ſhall not waſte
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              Time in explaining any ſuch curious Principles,
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              as that it is the Nature of all heavy Bodies to
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              preſs continually downwards, and obſtinately
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              to ſeek the loweſt Place; that they make the
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              greateſt Reſiſtance they are able againſt being
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              raiſed aloft, and never change their Place, but
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              after the ſtouteſt Conflict, being either over­
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              come by ſome greater Weight or ſome more
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              powerful contrary Force. </s>
              <s>Nor ſhall I ſtand to
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              obſerve that Motions are various, from high to
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              low or from low to high, directly, or about a
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              Curve; and that ſome Things are carried, ſome
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              drawn, ſome puſhed on, and the like; of
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              which Enquiries we ſhall treat more copiouſly
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              in another Place. </s>
              <s>This we may lay down for
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              certain, that a Weight is never moved with ſo
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              much Eaſe as it is downwards; becauſe it then
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              moves itſelf, nor ever with more Difficulty,
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              than upwards; becauſe it naturally reſiſts that
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              Direction; and that there is a Kind of middle
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              Motion between theſe two, which perhaps par­
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              takes ſomewhat of the Nature of both the
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              others, inaſmuch as it neither moves of itſelf,
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              nor of itſelf reſiſts, as when a Weight is drawn
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              upon an even Plain, free from all Rubs. </s>
              <s>All
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              other Motions are eaſy or difficult in Proporti­
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              on as they approach to either of the preceding.
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              </s>
              <s>And indeed Nature herſelf ſeems in a good
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              Meaſure to have ſhewn us in what Manner
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              great Weights are to be moved: for we may
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              obſerve, that if any conſiderable Weight is laid
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              upon a Column ſtanding upright, the leaſt
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              Shove will puſh it off, and when once it be­
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              gins to fall, hardly any Force is ſufficient to
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              ſtop it. </s>
              <s>We may alſo obſerve, that any round
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              Column, or Wheel, or any other Body that
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              turns about, is very eaſily moved, and very
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              hard to ſtop when once it is ſet on going; and
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              if it is draged along without rowling, it does
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              not move with half the Eaſe. </s>
              <s>We further ſee,
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              that the vaſt Weight of a Ship may be moved
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              upon a ſtanding Water with a very ſmall Force,
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              if you keep pulling continually; but if you
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              ſtrike it with ever ſo great a Blow ſuddenly, it
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              will not ſtir an Inch: On the Contrary, ſome
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              Things will move with a ſudden Blow or a fu­
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              rious Puſh, which could not otherwiſe be ſtirred
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              without a mighty Force or huge Engines.
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              </s>
              <s>Upon Ice too the greateſt Weights make but a
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              ſmall Reſiſtance, againſt one that tries to draw
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              them. </s>
              <s>We likewiſe ſee that any Weight which
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              hangs upon a long Rope, is very eaſily moved
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              as far as a certain Point; but not ſo eaſily, fur­
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              ther. </s>
              <s>The Conſideration of the Reaſons of
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              theſe Things, and the Imitation of them, may
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              be very uſeful to our Purpoſe; and therefore
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              we ſhall briefly treat of them here. </s>
              <s>The Keel
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              or Bottom of any Weight, that is to be drawn
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              along, ſhould be even and ſolid; and the
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              Broader it is, the leſs it will plough up the
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              Ground all the Way under it, but then the
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              Thinner it is, it will ſlip along the Quicker,
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              only it will make the deeper Furrows, and be
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              apter to ſtick: If there are any Angles or Ine­
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              qualities in the Bottom of the Weight, it will
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              uſe them as Claws to faſten itſelf in the Plain,
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              and to reſiſt its own Motion. </s>
              <s>If the Plain be
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              ſmooth, ſound, even, hard, not riſing or ſink­
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              ing on any Side, the Weight will have nothing
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              to hinder its Motion, or to make it reſuſe to
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              obey, but its own natural Love of Reſt, which
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              makes it lazy and unwilling to be moved.
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              </s>
              <s>Perhaps it was from a Conſideration of theſe
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              Things, and from a deeper Examination of the
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              Particulars we have here mentioned, and
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              Ar­
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              chimedes
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              was induced to ſay, that if he had on­
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              ly a Baſis for ſo immenſe a Weight, he would
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              not doubt to turn the World itſelf about. </s>
              <s>The
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              Preparation of the Bottom of the Weight and </s>
            </p>
          </chap>
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    </archimedes>
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