IMPROVED PROPELLERS FOR SHIPS.

Southland Times, Volume I, Issue 39, 24 March 1863, Page 5 (Supplement)

IMPROVED PROPELLERS FOR SHIPS.

The Mechanic's Magazine gives the following description of a newly invented propeller, which is said to possess considerable advantage over the screw at present in use : — " This invention, recently patented by Mr. R. Vaile, of Maida Hill, and Auckland, New Zealand, consists of endless chains of peculiar construction, having floats attached to them. The chains and floats pass round collars or drums mounted upon shafts which are driven by steam or other power. The whole of the floats and chains above the water-line are enclosed in a suitable casing. The chains are made of flat links, each alternate link having a tooth on its upper side, wMch takes into indentations formed in the collars, while the alternate links lie in suitable slots. The floats are connected to the chains by means of links forming part of the chain, and made with an eye for receiving a pin, secured to a float by straps. The upper parts of the floats have portions cut away to allow of their working between the collars. Each float is furnished with projecting arms carrying rollers, and a central flanged roller. The projections act upon the guide, and prevent the floats entering the water in a wrong position, the lower frame is fixed to some part of the vessel, so that the floats may work below the water line. The inventor prefers to fix two propellers, one on each side of the keel, and at or about the centre of the ship. The frame is formed with double sides, and with a groove, with Surfaces for the rollers to travel on. The frame carries the bearings for the support of the shafts and collars. The chains are carried round for the purpose of keeping the chains tight. They may be acted upon by jacks or otherwise. Upon rotary motion being communicated to the shaft of the collars the floats are caused to move. When travelling along the upper part of the frame, the floats lie parallel with the chains, the flanged rollers resting upon rails formed to receive them. As soon as each float reaches a certain point it commences to alter its position ; and whether it descends in the reversed position or not, then its arms, coming into contact with the sloped or curved ends of the guides, it is made to retain that position by rollers coming in contact with bottom of the upper surface of the groove, and the central flanked roller coming in contact with the flange. In this position the floats are maintained until they are feathered to leave the water. This feathering is effected by the pressure of the water, and the contact of the appliances attached to the floats and guides. The floats then lie parallel with the chains. In order to "go astern," it is simply necessary to reverse the engine, thus changing the direction of rotation of the collars and chains when the same positions will be assumed by the floats passing over the smaller collars, and in their course from those collars to the larger collars, as when assumed by them when propelling " ahead,' 1 as before mentioned.