Abstract: Sensitive rotating viscometers which include a head, rotor and stator, for example, a Brookfield viscometer, and have their head supported by a hollow housing and their stator held in place by the same hollow housing are improved by an internally threaded wall in a lower portion of the hollow support member, having means to exert guiding pressure on a means to accept pressure of a correspondingly, externally threaded nut, the correspondingly, externally threaded nut for attachment within the internally threaded wall, which threaded nut has an extension which is perforately slotted, the nut extension having the means to accept pressure, so as to cause the nut extension to be directed inwardly by tightening of the nut within the internally threaded wall, so as to cause snug contact between the lower interior surface of the hollow support member and the exterior cylindrical surface of the stator. The device may be embodied as a separable collar housing and stator/tube collar with such an aforesaid nut.

Abstract: A boat propeller wherein the blades are easily removable from the propeller hub on an individual basis to permit quick replacement for repair and/or for substituting blades of different pitch comprising a hub adapted to fit over and attach to a drive shaft; a plurality of removable blades positioned around said hub and extending radially therefrom, each of said blades comprising a water engaging blade portion and a rigid tang extending from the base and of such blade portion; a plurality of blade engaging sockets disposed on and around said hub, said sockets adapted to mate with and receive the tang of said blades; and preferably a cover plate adapted to fit over the portion of said tang within said socket, tang, cover plate each being provided with a plurality of aligned bolt holes; and a plurality of bolts extending through said aligned holes and holding each assembly thereof together. Further modifications include a blade assembly for use wherein less force will be exerted, e.g.