RAILWAY MOTOR-CARS
In the early days of railway construction vehicles were used which combined a steam locomotive with an ordinary passenger carriage. After being abandoned for many years, the "steam carriage" was revived, in 1902, by the London and South Western and Great Western railways for local service and the handling of passenger traffic on branch lines. Since that year rail motor-cars have multiplied; some being run by steam, others by petrol engines, and others, again, by electricity generated by petrol engines. The first class we need not describe in any detail, as it presents no features of peculiar interest.
The North Eastern has had in use two rail-motors, each fifty-two feet long, with a compartment at each end for the driver, and a central saloon to carry fifty-two passengers. An 80 h.p. four-cylindered Wolseley petrol motor drives a Westinghouse electric generator, which sends current into a couple of 55 h.p. electric motors geared to the running-wheels. An air compressor fitted to the rear bogie supplies the Westinghouse air brakes, while in addition a powerful electric brake is fitted, acting on the rails as well as the wheels. The coach scales thirty-five tons.
The chief advantage of this "composite" system of power transmission is that the engine is kept running at a constant speed, while the power it develops at the electric motors is regulated by switches which control the action of the armature and field magnets. When heavy work must be done the engine is supplied with more gaseous mixture, and the generators are so operated as to develop full power. In this manner all the variable speed gears and clutches necessary when the petrol motor is connected to the driving-wheels are done away with.
The latter system gives, however, greater economy of fuel, and the Great Northern Railway has adopted it in preference to the petrol-electric. This railway has many small branch lines running through thinly populated districts, which, though important as feeders of the main tracks, are often worked at a loss. A satisfactory type of automobile carriage would not only avoid this loss, but also largely prevent the competition of road motors.
The car should be powerful enough to draw an extra van or two on occasion, since horses and heavy luggage may sometimes accompany the passengers. Messrs. Dick, Kerr, and Company have built a car, which, when loaded with its complement of passengers, weighs about sixteen tons. The motive power is supplied by two four-cylinder petrol engines of the Daimler type, each giving 36 h.p. These are suspended on a special frame, independent of that which carries the coach body, so that the passengers are not troubled by the vibration of the engines, even when the vehicle is at rest. The great feature of the car is the lightness of the machinery—only two tons in weight—though it develops sufficient power to move the carriage at fifty miles per hour. After travelling 2,000 miles the machinery showed no appreciable signs of wear; so that the company considers that it has found a reliable type of motor for the working of the short line between Hatfield and Hertford.
Since one man can drive a petrol car, while two—a driver and a stoker—are necessary on a steam car, a considerable reduction in wages will result from the employment of these vehicles.
Engineers find motor-trolleys very convenient for inspecting the lines under their care. On the London and South Western Railway a trolley driven by a 6–8 h.p. engine, and provided with a change-gear giving six, fifteen, and thirty miles per hour in either direction, is at work. It seats four persons. In the colonies, notably in South Africa, where coal and wood fuel is scarce or expensive, the motor-trolley, capable of carrying petrol for 300 miles' travel, is rapidly gaining ground among railway inspectors.
Makers are turning their attention to petrol shunting engines, useful in goods yards, mines, sewerage works. Firms such as Messrs. Maudslay and Company, of Coventry; the Wolseley Tool and Motor Car Company; Messrs. Panhard and Levassor; Messrs. Kerr, Stuart, and Company have brought out locomotives of this kind which will draw loads up to sixty tons. The fact that a petrol engine is ready for work at a moment's notice, and when idle is not "eating its head off," and has no furnace or boiler to require attention, is very much in its favour where comparatively light loads have to be hauled.
[CHAPTER VIII]
THE MOTOR AFLOAT
PLEASURE BOATS — MOTOR LIFEBOATS — MOTOR FISHING BOATS — A MOTOR FIRE FLOAT — THE MECHANISM OF THE MOTOR BOAT — THE TWO-STROKE MOTOR — MOTOR BOATS FOR THE NAVY
Having made such conquests on land, and rendered possible aerial feats which could scarcely have been performed by steam, the explosion motor further vindicates its versatility by its fine exploits in the water.
At the Paris Exhibition of 1889 Gottlieb Daimler, the inventor who made the petrol engine commercially valuable as an aid to locomotion, showed a small gas-driven boat, which by most visitors to the Exhibition was mistaken for an ordinary steam launch, and attracted little interest. Not deterred by this want of appreciation, Mr. Daimler continued to perfect the idea for which, with a prophet's eye, he saw great possibilities; and soon motor launches became a fairly common sight on German rivers. They were received with some enthusiasm in the United States, as being particularly suitable for the inland lakes and waterways with which that country is so abundantly blessed; but met with small recognition from the English, who might reasonably have been expected to take great interest in any new nautical invention. Now, however, English manufacturers have awaked fully to their error; and on all sides we see boats built by firms competing for the lead in an industry which in a few years' time may reach colossal proportions.
A MODERN CAR AND BOAT
In the background is the racing motor boat "Napier II.", which on a trial trip travelled over the "measured mile" at 30·93 miles per hour. In the foreground is a "Napier" racing car, which has attained a speed of 104·8 miles per hour.
Until quite recently the marine motor was a small affair, developing only a few horse-power. But because the gas-engine for automobile work had been so vastly improved in the last decade, it attracted notice as a rival to steam for driving launches and pleasure boats, and soon asserted itself as a reliable mover of vessels of considerable size. To promote the development of the industry, to test the endurance of the machine, and to show the weak spots of mechanical design, trials and races were organised on much the same lines as those which have kept the motor-car so prominently before the public—races in the Solent, across the Channel, and across the Mediterranean. The speed, as in the case of cars, has risen very rapidly with the motor boat. When, in February, 1905, a Napier racer did some trial spins over the measured mile in the Thames at Long Reach, she attained 28·57 miles per hour on the first run. On turning, the tide was favourable, and the figures rose to 30·93 m.p.h., while the third improved on this by over a mile. Her mean speed was 29·925 m.p.h., or about 2 / 3 m.p.h. better than the previous record—standing to the credit of the American Challenger. The latter had, however, the still waters of a lake for her venue, so that the Napier's performance was actually even more creditable than the mere figures would seem to imply. At a luncheon which concluded the trial, Mr. Yarrow, who had built the steel hull, said: "To give an idea of what an advance the adoption of the internal combustion engine really represents, I should like to state that, if we were asked to guarantee the best speed we could with a boat of the size of Napier II., fitted with the latest form of steam machinery of as reliable a character as the internal combustion engine in the present boat, we should not like to name more than sixteen knots. So that it may be taken that the adoption of the internal combustion engine, in place of the steam-engine, for a vessel of this size, really represents an additional speed of ten knots an hour. I should here point out that the speed of a vessel increases rapidly with its size. For example: in what is termed a second-class torpedo boat, sixty feet in length, the best speed we could obtain would be twenty knots; but for a vessel of, say, 200 feet in length, with similar but proportionately larger machinery, a speed of thirty knots could be obtained. Therefore, the obtaining of a speed of practically twenty-six knots in the Yarrow-Napier boat, only forty feet in length, points to the possibility, in the not far-distant future, of propelling a vessel 220 feet in length at even forty-five knots per hour. All that remains to be done is to perfect the internal combustion engine, so as to enable large sizes to be successfully made."
Boats of 300 h.p. and upwards are being built; and the project has been mooted of holding a transatlantic race, open to motor boats of all sizes, which should be quite self-contained and able to carry sufficient fuel to make the passage without taking in fresh supplies. In view of the perils that would be risked by all but large craft, and in consideration of the prejudice that motor boats might incur in event of any fatalities, the Automobile Club of France set its face against the venture, and it fell through. It is possible, however, that the scheme may be revived as soon as larger motor boats are afloat, since the Atlantic has actually been crossed by a craft of 12 h.p., measuring only forty feet at the water-line. This happened in 1902, when Captain Newman and his son, a boy twelve years old, started from New York, and made Falmouth Harbour after thirty days of anxious travel over the uncertain and sometimes tempestuous ocean. The boat, named the Abiel Abbot Low, carried auxiliary sails of small size, and was not by any means built for such a voyage. The engine—a two-cylinder—burned kerosene. Captain Newman received £1,000 from the New York Kerosene Oil Engine Company for his feat. The money was well earned. Though provided with proper navigating instruments—which he knew how to use well—Newman had a hard time of it to keep his craft afloat, his watches sometimes lasting two days on end when the weather was bad. Yet the brave pair won through; and probably even more welcome than the sense of success achieved and the reward gained was the long two-days' sleep which they were able to get on reaching Falmouth Harbour.