Pulley
A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable, or belt along its circumference. Pulleys are used in a variety of ways to lift loads, apply forces, and to transmit power. In nautical contexts, the assembly of wheel, axle, and supporting shell is referred to as a "block."
A pulley may also be called a sheave or drum and may have a groove or grooves between two flanges around its circumference. The drive element of a pulley system can be a rope, cable, belt, or chain that runs over the pulley inside the groove or grooves.
Hero of Alexandria identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another.
Suspension
Suspension bondage is a form of sexual bondage where a bound person is hung from one or more overhead suspension points. (Suspension bondage is considered a higher risk than most other forms of sexual bondage: see Risks below.)
In partial suspension the person is bound in such a way that part of their body weight is held by suspension ropes, cables or chains. The classic partial suspension position is to have the person balancing on one foot with part of their weight supported through a chest harness and the other leg pulled up in some direction. A person lying on their upper back with legs tied upwards to a suspension point to pull their lower back off the ground would also qualify as partial suspension.
In full suspension the person is completely supported by suspension ropes, cables or chains, and they have no contact with the ground. The position of the person's body in a full suspension is only limited by their endurance and the skill of the rigger.
Sheila's maid
A Sheila Maid, sometimes Sheila's Maid, is the British name for a ceiling mounted clothes and laundry airer. In the North of England it is often known as a creel, in Scotland as a pulley, and in United States as a Sheila Maid.
The airer consists of a rack with several horizontal wooden rails, usually 4 to 7, known as laths, with two rack ends, originally cast iron. The rack ends are brackets that separate the laths and also act as points to secure the cords that raise and lower the unit. Cords go from the metal tether points to pulleys mounted on the ceiling, and then to a cleat mounted on the wall.
The defining feature of this airer is its pulley system. The airer is lowered to be loaded or unloaded, then raised to move the items up into warmer air and as out of the way of room occupants as the ceiling height allows.
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