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314 dangerous side-slips than are ordinary leg-propelled cycles. On a slippery road with the ordinary bicycle there is only the rider and the bicycle in question, but in the case of the motor bicycle the engine makes its presence felt, lessening that instantaneous and automatic control so essential for safety. The Minerva engine has been adopted on many bicycles. It is now of 1$1⁄2$ h.-p.; the carburetter is a simple form of the surface type, and the petrol consumption stated to be about one pint for twelve to fourteen miles on level roads. The engine can also be lubricated without dismounting. In the Minerva motor bicycle the engine is fixed below the bottom tube of the frame slightly forward of the bottom bracket. The Excelsior was one of the first British motor bicycles in which the Minerva engine and system was adopted. Indeed, the extensive employment of the Minerva motor is one of the most astonishing features of the present development in motor bicycles. It is noteworthy, however, that several leading makers, while using the Minerva, have introduced in connection with it a number of special features which considerably facilitate the handling of the machine.

In the Quadrant motor cycle matters are simplified by one lever being made to control the switch, open and close the exhaust-valve, regulate the gas-supply, and vary the sparking. This reduction of the number of levers is undoubtedly a step in the right direction. The gas can be supplied in varying quantities, as usual, and is regulated by the lever from the lowest to the fullest supply before the advance of the sparking begins. Then when a greater speed is sought, it is obtained by the advance of the sparking, according to the pace desired, or in other words, the explosions are more rapid, the quantity of gas used being, of course, the full charge. In the ordinary arrangement it is possible to vary the supply of gas allowed to pass to the explosion chamber with the sparking lever at any point. Whether the restrictions imposed in this direction by the Quadrant device will prove to be a drawback has yet to be tested.