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60 of speed but it entailed a jockey pulley to take up the slack of the chain because there was no arrangement to lengthen the distance between the chain wheel centres when the chain encircled the smaller sprocket, i.e. when the high gear was in use. To show that Linley and Biggs were very practical cycle engineers, very much in advance of their time, a device resembling their original idea has been patented quite recently, but is too crude to have much chance of competing with the refined hub gears of to-day.

Following Linley and Biggs' patent, the next device to claim attention was a two-speed hub made by a Manchester firm and designed by a Mr. Ryley. There had been the G. and J. two-speed hub, the Planet two-speed hub, the Paradox two-speed crank axle gear, and one or two others.

The Hub Two-Speed Gear Co.'s two-speed hub may be said to be the father of all practical hub gears and was sold in considerable numbers. Detailed explanations of these gears would not be understood by non-technical readers, so it will suffice to say that by means of a train of pinions and a sliding member operated by a rod passing through the centre of the hub axle, the changes of gear ratio are made. The rider moves the rod in and out by pulling on it through the medium of a small lever on the top tube of the bicycle, and a wire which runs over a roller from the lever end along the top tube to the roller and down the side of the back stay. The movement can also be effected by Bowden flexible cable from the handle-bar, thus making it unnecessary to release the handle-bar for changing gear.

While the Hub Co.'s two-speed was being sold and gaining considerable popularity, other firms commenced experiments with hub gears. Notable among these were the Eadie Co., who took up Pagan's patent, the