Did the Romans invent the treadwheel crane?

Answer 1

Yes. The Greeks invented cranes with the invention of the winch and pulley hoist. The Romans invented the treadwheel crane.

The Romans adopted the cranes of the Greeks and massively improved on them. The simplest one was the trispastos, which had of a single-beam, a winch, a rope, and a block with three pulleys. It had had a mechanical advantage of 3:1, and single man operating the winch could raise 150 kg. The pentaspastos had five pulleys and the polyspastos had a set of three by five pulleys with two, three or four masts. The latter was worked by four men at both sides of the winch and could lift 3,000 kg. When the winch was replaced by a treadwheel, the load could be doubled to 6,000 kg with only half the crew, because the treadwheel had a larger diameter and thus a much bigger mechanical advantage.