Alberti, Leone Battista, Architecture, 1755

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1Pyramid 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

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