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Rh before they have had time to work their way through the tread.

To reduce the probability of puncture in patches of loose stones, let the car run as much as possible by gravity, and not by driving friction.

Various attempts have been made to produce efficient tyres for motor-cars without infringement of the Dunlop patents. At present (1902) there is only a restricted experience to call upon in respect of these new types, but the appended enumeration of their leading features is based upon personal investigations among actual users.

The Collier.—As will be seen from the sectional illustration (fig. 15), this type is provided with an unusually stout tread, and is made in very large diameters. The mode of fastening is by vertical bolts passing through a horizontal flange of metal which is shrunk on to each side of the wooden felloe. The upper ends of the bolts are ringed, and receive a wire which passes all round the bead of the cover, on each side of the wheel alike. To remove the tyre when deflated it is only necessary to unscrew the locking nuts outside the flange, and, as the wire threaded through the rings is not endless, the bolts can be pushed inwards and the edge of the cover lifted without difficulty, especially as it only engages with a flat surface, and not the tuned edge of a rim of the ordinary pattern. The cost of the Collier is about 25 per cent in excess of ordinary types. Not only is excellent rubber employed, however, but the system of moulding is such that even on a heavy car the tyres show fewer cuts than solids. I have seen a set of Colliers on a 27-cwt. car that had been driven 2,300 miles over bad roads, and even the covers of the driving wheels were quite smooth