Alberti, Leone Battista, Architecture, 1755

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              <s>
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              and we may guide it which way we think
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              proper by means of the two ſide Ropes, as with
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              two Reins, making it either ſtand upright
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              whenever we find it neceſſary, or ſtoop which­
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              ſoever way we Pleaſe to ſet down the Weight
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              in the proper place. </s>
              <s>As to theſe two ſide
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              Ropes, if you have no greater Weight to faſten
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              them to, you may fix them in the following
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              Manner: Dig a ſquare Pit in the Ground, and
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              in it lay the Trunk of a Tree, to which faſten
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              one or more Loops that may ſtand up out of
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              the Ground; then lay ſome croſs Timbers over
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              the Trunk, and fill up the Pit with Earth, ram­
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              ming it down very cloſe, and if you wet it, it
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              will be the heavier. </s>
              <s>In all the other Particu­
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              lars, you may obſerve the Rules we have laid
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              down as to the Plain on which the Weight is
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              to ſlide: For you muſt faſten Pullies both to
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              the Head of the Maſt and to the Weight which
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              is to be raiſed, and near the Foot of the Maſt
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              you muſt fix your Capſtern, or whatever other
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              Inſtrument you uſe that acts with the Power of
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              the Leaver. </s>
              <s>In all Engines of this Nature de­
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              ſigned for the moving of great Weights, we
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              ſhould take Care that none of the Parts of the
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              Machine which are to have any Streſs upon
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              them, be too ſmall, and that none of our
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              Ropes, Spokes, or any other Medium which
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              we uſe in the Movement be weak by means of
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              their Length; for indeed long and thin are in
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              a Manner ſynonimous Terms, and ſo, on the
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              Contrary, are ſhort and thick. </s>
              <s>If the Ropes
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              are ſmall let them run double in the Pullies;
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              if they are very thick, you muſt get larger
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              Pullies, that the Rope may not be cut by the
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              Edges of the Pully-wheel. </s>
              <s>The Axis of the
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              Pully ſhould be Iron, and not leſs in Thickneſs
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              than the ſixth Part of the Semidiameter of the
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              Pully itſelf, nor more than the eighth Part of
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              the whole Diameter. </s>
              <s>If the Rope be wetted,
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              it will be the more ſecure from taking Fire,
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              which ſometimes happens by means of its Mo­
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              tion and Friction in the Pully; it will alſo turn
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              the Pully round the better, and keep better
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              within the Wheel. </s>
              <s>It is better to wet the
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              Rope with Vinegar than with Water; but if
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              you do it with Water, Sea-water is beſt. </s>
              <s>If
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              you wet with freſh Water, and it is expoſed to
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              the Heat of the Sun, it will rot preſently.
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              </s>
              <s>Twiſting the Ropes together is much ſafer than
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              tying them; and eſpecially you muſt take Care
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              that one Rope does not cut the other. </s>
              <s>The
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              Ancients uſed a Bar or Rule of Iron, to which
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              they faſtened the firſt Knots of their Ropes,
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              and their Pullies, and for taking up any Weight,
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              and eſpecially of Stone, they had a Kind of
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              Pincers or Forceps of Iron. </s>
              <s>The Shape of
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              theſe Pincers or Forceps was taken from the
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              Letter X, the lower Limbs of it being turned
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              inwards like a Crab's Claw, by which means it
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              faſtened itſelf to the Weight. </s>
              <s>The two upper
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              Limbs had Holes at the Top, through which
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              they put a Rope, which being tied, and ſtrain­
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              ed tight by the moving Force, made the Teeth
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                <arrow.to.target n="marg14"/>
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              of the Pincers keep cloſer to the Weight -A-.
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              In very large Stones, and eſpecially in the
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              Middle of Columns, though perfectly ſmooth
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              in all other Parts, I have ſeen little Knobs left
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              jutting out, like Handles, againſt which the
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              Ropes were hitched, to prevent their ſlipping.
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              </s>
              <s>It is alſo common, eſpecially in Cornices, to
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              make a Hole in the Stone like a Mortiſe, after
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              this Manner; you make a Hole in the Stone
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              like an empty Purſe, of a Bigneſs anſwerable
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              to the Size of the Stone, narrower at the Mouth
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              than at the Bottom. </s>
              <s>I have ſeen ſome of theſe
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              Holes a Foot deep. </s>
              <s>You then fill it with iron
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                <arrow.to.target n="marg15"/>
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              Wedges, -B-the two ſide Wedges being ſhap­
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              ed like the letter D, which are put in firſt to
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              fill up the Sides of the Hole, and the middle
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              Wedge is put in laſt between theſe two. </s>
              <s>All
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              theſe three Wedges have their Ears which pro­
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              ject out beyond the Mortiſe, and theſe Ears
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              have a Hole drilled in them, through which
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              you put an iron Pin, which faſtens on a ſtrong
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              Handle or Ring; and to this Ring you faſten
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              the Rope which runs through the Pully that
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              is to draw up the Weight. </s>
              <s>My way of faſten­
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              ing my Ropes about Columns, Jambs of Doors,
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              and other ſuch Stones which are to be ſet up­
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              right, is as follows. </s>
              <s>I make a Cincture or
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              Hoop of Wood or Iron of a due Strength for
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              bearing the Weight which I am to move, and
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              with this Hoop I ſurround the Column or
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              other Stone in ſome convenient Part, making
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              it tight to the Stone with long thin Wedges
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              drove in gently with a Hammer, then I faſten
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              my Ligatures to this Hoop, and by this Means
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              I neither ſpoil the Beauty of the Stone by ma­
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              king Mortiſes in it, nor break the Edges of the
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              Jambs by the Rubbing of the Ropes againſt
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              them: Beſides that it is the moſt expeditious,
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              convenient and ſafeſt Way of faſtening the
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              Ropes that has been thought of. </s>
              <s>In another
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              Place I ſhall enlarge more particularly upon
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              many Things relating to this Subject. </s>
              <s>All I
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              ſhall obſervc further here is, that all Engines
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              may be looked upon to be a Sort of Animals,
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              with prodigious ſtrong Hands; and that they
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              move Weights juſt in the ſame Manner as we
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              </s>
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