Part 18 (1/2)
Many schemes are afoot for the construction of high-speed railways.
The South-Eastern plans a monorail between Cannon Street and Charing Cross to avoid the delay that at present occurs in pa.s.sing from one station to the other. We hear also of a projected railway from London to Brighton, which will reduce the journey to half-an-hour; and of another to connect Dover and London. It has even been suggested to establish monorails on existing tracks for fast pa.s.senger traffic, the expresses pa.s.sing overhead, the slow and goods trains plodding along the double metals below.
But the most ambitious programme of all comes from the land of the Czar. M. Hippolyte Romanoff, a Russian engineer, proposes to unite St.
Petersburg and Moscow by a line that shall cover the intervening 600 miles in three hours--an improvement of ten hours on the present time-tables. He will use T-shaped supports to carry two rails, one on each arm, from which the cars are to hang. The line being thus double will permit the cars--some four hundred in number--to run to and fro continuously, urged on their way by current picked up from overhead wires. Each car is to have twelve wheels, four drivers arranged vertically and eight horizontally, to prevent derailment by gripping the rail on either side. The stoppage or breakdown of any car will automatically stop those following by cutting off the current.
In the early days of railway history lines were projected in all directions, regardless of the fact whether they would be of any use or not. Many of these lines began, where they ended, on paper. And now that the high-speed question has cropped up, we must not believe that every projected electric railway will be built, though of the ultimate prevalence of far higher speeds than we now enjoy there can be no doubt.
The following is a time-table drawn up on the two-mile-per-minute basis.
A man leaving London at 10 A.M. would reach--
Brighton 50 miles away, at 10.25 A.M.
Portsmouth 60 ” ” 10.30 A.M.
Birmingham 113 ” ” 10.57 A.M.
Leeds 188 ” ” 11.34 A.M.
Liverpool 202 ” ” 11.41 A.M.
Holyhead 262 ” ” 12.11 P.M.
Edinburgh 400 ” ” 1.20 P.M.
Aberdeen 540 ” ” 2.30 P.M.
What would become of the records established in the ”Race to the North” and by American ”fliers”?
And what about continental travel?
a.s.suming that the Channel Tunnel is built--perhaps a rather large a.s.sumption--Paris will be at our very doors. A commercial traveller will step into the lightning express at London, sleep for two hours and twenty-four minutes and wake, refreshed, to find the blue-smocked Paris porters bawling in his ear. Or even if we prefer to keep the ”little silver streak” free from subterranean burrows, he will be able to catch the swift turbine steamers--of which more anon--at Dover, slip across to Calais in half-an-hour, and be at the French capital within four hours of quitting London. And if M. Romanoff's standard be reached, the latest thing in hats despatched from Paris at noon may be worn in Regent Street before two o'clock.
Such speeds would indeed produce a revolution in travelling comparable to the subst.i.tution of the steam locomotive for the stage coach. As has been pithily said, the effect of steam was to make the bulk of population travel, whereas they had never travelled before, but the effect of the electric railway will be to make those who travel travel much further and much oftener.
SEA EXPRESSES.
In the year 1836 the _Sirius_, a paddle-wheel vessel, crossed the Atlantic from Cork Harbour to New York in nineteen days. Contrast with the first steam-pa.s.sage from the Old World to the New a return journey of the _Deutschland_, a North German liner, which in 1900 averaged over twenty-seven miles an hour between Sandy Hook and Plymouth, accomplis.h.i.+ng the whole distance in the record time of five days seven hours thirty-eight minutes.
This growth of speed is even more remarkable than might appear from the mere comparison of figures. A body moving through water is so r.e.t.a.r.ded by the inertia and friction of the fluid that to quicken its pace a force quite out of proportion to the increase of velocity must be exerted. The proportion cannot be reduced to an exact formula, but under certain conditions the speed and the power required advance in the ratio of their cubes; that is, to double a given rate of progress eight times the driving-power is needed; to treble it, twenty-seven times.
The mechanism of our fast modern vessels is in every way as superior to that which moved the _Sirius_, as the beautifully-adjusted safety cycle is to the clumsy ”boneshaker” which pa.s.sed for a wonder among our grandfathers. A great improvement has also taken place in the art of building s.h.i.+ps on lines calculated to offer least resistance to the water, and at the same time afford a good carrying capacity. The big liner, with its knife-edged bow and tapering hull, is by its shape alone eloquent of the high speed which has earned it the t.i.tle of Ocean Greyhound; and as for the fastest craft of all, torpedo-destroyers, their designers seem to have kept in mind Euclid's definition of a line--length without breadth. But whatever its shape, boat or s.h.i.+p may not shake itself free of Nature's laws. Her restraining hand lies heavy upon it. A single man paddles his weight-carrying dinghy along easily at four miles an hour; eight men in the pink of condition, after arduous training, cannot urge their light, slender, racing sh.e.l.l more than twelve miles in the same time.
To understand how mail boats and ”destroyers” attain, despite the enormous resistance of water, velocities that would shame many a train-service, we have only to visit the stokeholds and engine-rooms of our sea expresses and note the many devices of marine engineers by which fuel is converted into speed.
We enter the stokehold through air-locks, closing one door before we can open the other, and find ourselves among sweating, grimy men, stripped to the waist. As though life itself depended upon it they shovel coal into the rapacious maws of furnaces glowing with a dazzling glare under the ”forced-draught” sent down into the hold by the fans whirling overhead. The ignited furnace gases on their way to the outer air surrender a portion of their heat to the water from which they are separated by a skin of steel. Two kinds of marine boiler are used--the fire-tube and the water-tube. In fire-tube boilers the fire pa.s.ses inside the tubes and the water outside; in water-tube boilers the reverse is the case, the crown and sides of the furnace being composed of sheaves of small parallel pipes through which water circulates. The latter type, as generating steam very quickly, and being able to bear very high pressures, is most often found in war vessels of all kinds. The quality sought in boiler construction is that the heating surface should be very large in proportion to the quant.i.ty of water to be heated. Special coal, anthracite or Welsh, is used in the navy on account of its great heating power and freedom from smoke; experiments have also been made with crude petroleum, or liquid fuel, which can be more quickly put on board than coal, requires the services of fewer stokers, and may be stored in odd corners unavailable as coal bunkers.
From the boiler the steam pa.s.ses to the engine-room, whither we will follow it. We are now in a bewildering maze of clanking, whirling machinery; our noses offended by the reek of oil, our ears deafened by the uproar of the moving metal, our eyes wearied by the efforts to follow the motions of the cranks and rods.
On either side of us is ranged a series of three or perhaps even four cylinders, of increasing size. The smallest, known as the high-pressure cylinder, receives steam direct from the boiler. It takes in through a slide-valve a supply for a stroke; its piston is driven from end to end; the piston-rod flies through the cylinder-end and transmits a rotary motion to a crank by means of a connecting-rod.
The half-expanded steam is then ejected, not into the air as would happen on a locomotive, but into the next cylinder, which has a larger piston to compensate the reduction of pressure. Number two served, the steam does duty a third time in number three, and perhaps yet a fourth time before it reaches the condensers, where its sudden conversion into water by cold produces a vacuum suction in the last cylinder of the series. The secret of a marine engine's strength and economy lies then in its treatment of the steam, which, like clothes in a numerous family, is not thought to have served its purpose till it has been used over and over again.