Shear legs to the gin pole, derrick and tripod (lifting device). Shears are an A-frame of any kind of material such as timbers or metal, the feet resting on or in the ground or on a solid surface which will not let them move and the top held in place with guy-wires or guy ropes simply called "guys". Shear legs only need two guys whereas a gin pole needs at least three. The U. S. Army Field Manual FM 5-125 gives detailed instruction on how to rig shears. Fixed shear legs are most commonly found on floating cranes known as floating sheerlegs.
Starfish and fatty acid amides of sphingosine. The steroids are mostly saponins, known as asterosaponins, and their sulphated derivatives. They vary between species and are typically formed from up to six sugar molecules (usually glucose and galactose) connected by up to three glycosidic chains. Long-chain fatty acid amides of sphingosine occur frequently and some of them have known pharmacological activity. Various ceramides are also known from starfish and a small number of alkaloids have also been identified. The functions of these chemicals in the starfish have not been fully investigated but most have roles in defence and communication. Some are feeding