Crane with winches for the elevation of mast and load
Its mast was constituted by two gigantic pieces
of wood in the form of Λ.
Its articulation was ensured by two dents in the horizontall joist at the base.
Its stabilisation in various inclinations was achieved by two balancing ropes
that were tautened with hoists and the rear winch (via removable levers). The
load was raised or lowered with the help of two traction ropes , the hoist
"trispaston" and a winch with horizontal axle, the "reel",
(where the rope for the elevation of the load was wrapped) and was rotated
(around specific bases, "tortoise - like cases" that were fitted on
the mast) with the help of constant radial levers.
The rear winch was also essential for the
lifting and lowering of the mast itself at the beginning and the end of work.
The friction between the ends of the axles of the winches and points of their
bases ensured their easy stabilisation.
The crane was placed on rollers for its
sideward shifting.
SOURCES: "Vitrouvius, On architecture
X"
A crane of two-sided elevation
It consisted of a moving (on wooden rollers)
platform and a vertical frame in the shape of “Π” that had a hoist ("polispasto") on its top and a radiated
winch for the elevation of the load on its base. On the two sides of the
platform there were winches to control the frame inclination. It was suitable
for loading or unloading ships but also for the construction of piers as it is
described by the excavation team of Jean- Yves Empereour at the Cyprus Amathous
port. The stone was tightened (from the "U" shaped handles at both
sides) at the back side of the platform, then it was raised using the central
winch and then moved to the front side of the platform using a combination of
pulling and loosening on the front side and back side winch correspondingly.
Then the stone was brought down using the central winch (and since it could be
rotated) it was positioned inside the sea. The platform moved constantly
lengthwise on the built piers.
SOURCES: "Vitrouvius, On architecture
X", "Heron of Alexandria, Mechanics", "Pappos of
Alexandria, Mechanics", "Tony Kozelj, Manuela. Wurd- Kozelj,
Jean-Yves Empereour, Elevating mechanism for stone transport in Amathus
port"
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