Alberti, Leone Battista Architecture 1755, tr. Leoni, James

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