has led to the introduction of detachable rims and detachable
wheels. The detachable rim is borne on the periphery of the
wheel (which is bonded) and secured in position by various
methods. When the tire is punctured or damaged the rim and
tire are removed bodily and replaced by a spare rim with its
tire already in position and inflated, a change capable of
being effected in five minutes or less. The detachable wheel is
mounted upon a shell which fits over and is secured to a sleeve,
which latter turns and is secured upon the fixed axle. In the
case of tire trouble, the wheel intact is removed from the sleeve
(which in the case of a driving-wheel carries the driving fittings,
the brake-drums, &c.) and a duplicate wheel is substituted.
The pneumatic tire has undergone continuous improvement,
particularly in the matters of the selection of the material and
the proportioning of the strength of the “body” to the work
which the tire is to be called upon to perform. Various methods
have been devised for the prevention of skidding or “side-slip”
on greasy surfaces, and, whilst certain mouldings on the rubber
treads have proved advantageous, the method most adopted
is that in which a large number of steel studs stand about a
quarter of an inch above the surface of the tire.
Fig. 5.—Plan View of the 40–50 h.p. Six-Cylinder Rolls-Royce Chassis (1910 type).
It will be seen that the general lines of the car of 1889 have not required to be radically altered. Every detail has been improved so that the cars are more efficient, easier to control and manage, and infinitely more comfortable, but, in essence, Levassor’s scheme is as good to-day as it was when planned by him.
The steam car is made by five or six British manufacturers at the most, whereas the actual manufacturers of petrol cars in Great Britain numbered at the end of the year 1909 about seventy, whilst some four hundred other firms were actively engaged in the construction of cars and their parts, accessories and sundries. But the steam car appeals to those men who are or have been steam engineers, and to them the management of the steam generator and the burners constitutes no difficulty. The limitations under which the early steam car laboured have, in the main, disappeared, for the modern steamer can travel nearly as far without requiring to refill the boiler as a petrol car can travel without replenishment of the fuel tank. The electric car is still the luxury to be employed in towns and in covering short distances, for the weight of the accumulators has not been greatly reduced, despite sensational announcements made from time to time.
An interesting feature of the motor movement has been the steady growth in popularity of the motor cycle. The motor tricycle was developed up to the year 1903, and then gradually became displaced by the motor bicycle, which had been introduced in 1901. Motor bicycles gradually increased in popularity, until in numbers they were in excess of cars. The standard machines of 1909 had an air-cooled motor of one, two or even four cylinders (according to the choice of the riders) developing some 3 to 8 h.p. with magneto ignition and belt drive. The engine was usually started by the rider running alongside the machine, and causing the machine to rotate the crank-shaft through the belt and pulley until the initial explosion was obtained, when he would jump into the seat. Trailers were employed at first for carrying passengers, but, the length of the combined vehicle being between nine and ten feet, a side-car, placed at the side of the cycle and secured thereto by detachable fittings, largely displaced the trailer and also the “fore-car,” in which the passenger was carried in a body placed in front of three- and four-wheeled cycles.
The rapid growth of the motor movement in Great Britain may be judged from the fact that by the 30th of September 1905 the number of motor vehicles of all kinds registered had totalled to 74,038, and by the 30th of September 1908, three years afterwards, to no less than 154,415. Of these, 137,323 were registered in England and Wales, 10,907 in Scotland, and 6185 in Ireland. 71,405 were private motor-cars; 12,104 were trade motor-cars; 5880 were public service vehicles and 65,026 were motor cycles.
A year later (Sept. 30, 1909) the figures showed a further remarkable increase, the total number of vehicles registered in the United Kingdom being 183,773, giving an increase of 29,358 in the year. Of these, private motor-cars numbered 84,840; trade motor-cars 15,181; public service vehicles 8752; and motor cycles 75,000. The numbers registered in England and Wales Were: 74,748 private motor-cars; 13,961 trade motor-cars; 8131 public service vehicles and 66,341 motor cycles, or 163,181 in all. The figures for Scotland were: 6157 private motor-cars; 1056 trade motor-cars; 584 public service vehicles and 5296 motor cycles or 13,093 in all. The figures for Ireland were: 3935 private motor-cars; 164 trade motor-cars; 37 public service vehicles and 3363 motor cycles, or 7499 in all. In the year private motor-cars in the United Kingdom increased by 18·8%; trade motor-cars by 25·4%; public service vehicles by 48·8%, and motor-cycles by 15·3%.
It is possible to obtain a better idea of the number of motor vehicles in use from the returns of the commissioners of inland revenue. The total number of privately-owned cars for which licences were issued in 1908 was 48,019, of motor cycles 35,784, and of motor-driven hackney carriages 17,300. These figures may be compared with the registration figures already given for the year ending the 30th of September 1908. As accounting partly for the difference, a certain proportion of the registered vehicles (seeing that the figures include all vehicles in use on and after the 1st of January 1904, less those in respect of which the registrations have been cancelled) must have fallen into disuse and some vehicles will have been sold out of the country, whilst others will have been sold and re-registered with different authorities. But the life of the mechanism of a car, in one form or another, is of considerable length (there were, for instance, in use in 1910, as commercial vehicles, motor chassis that were put on the road in 1896), and it is considered that many registered but unlicensed cars remain for years capable of rendering useful service in emergencies or on special occasions, such as at election periods.
In 1906 an act of parliament authorized a census of production, which was taken in 1908, the statistics relating to 1907. These figures show that the output of complete motor vehicles in the United Kingdom in that year was 11,700 completed cars and chassis, and 3600 motor cycles, the total value of the productive work