What is "feathering screw"

Feathering \Feath"er*ing\, n.

1. (Arch.) Same as Foliation.

2. The act of turning the blade of the oar, as it rises from the water in rowing, from a vertical to a horizontal position. See To feather an oar, under Feather, v. t.

3. A covering of feathers.

   Feathering float (Naut.), the float or paddle of a feathering wheel.

   Feathering screw (Naut.), a screw propeller, of which the blades may be turned so as to move edgewise through the water when the vessel is moving under sail alone.

   Feathering wheel (Naut.), a paddle wheel whose floats turn automatically so as to dip about perpendicularly into the water and leave in it the same way, avoiding beating on the water in the descent and lifting water in the ascent.