Stories of Inventors - Part 4
Library

Part 4

THE FASTEST STEAMBOATS

In 1807, the first practical steamboat puffed slowly up the Hudson, while the people ranged along the banks gazed in wonder. Even the grim walls of the Palisades must have been surprised at the strange intruder.

Robert Fulton's _Clermont_ was the forerunner of the fleets upon fleets of power-driven craft that have stemmed the currents of a thousand streams and parted the waves of many seas.

The _Clermont_ took several days to go from New York to Albany, and the trip was the wonder of that time.

During the summer of 1902 a long, slim, white craft, with a single bra.s.s smokestack and a low deck-house, went gliding up the Hudson with a kind of crouching motion that suggested a cat ready to spring. On her deck several men were standing behind the pilot-house with stop-watches in their hands. The little craft seemed alive under their feet and quivered with eagerness to be off. The pa.s.senger boats going in the same direction were pa.s.sed in a twinkling, and the tugs and sailing vessels seemed to dwindle as houses and trees seem to shrink when viewed from the rear platform of a fast train.

Two posts, painted white and in line with each other--one almost at the river's edge, the other 150 feet back--marked the starting-line of a measured mile, and were eagerly watched by the men aboard the yacht. She sped toward the starting-line as a sprinter dashes for the tape; almost instantly the two posts were in line, the men with watches cried "Time!"

and the race was on. Then began such a struggle with Father Time as was never before seen; the wind roared in the ears of the pa.s.sengers and s.n.a.t.c.hed their words away almost before their lips had formed them; the water, a foam-flecked streak, dashed away from the gleaming white sides as if in terror. As the wonderful craft sped on she seemed to settle down to her work as a good horse finds himself and gets into his stride.

Faster and faster she went, while the speed of her going swept off the black flume of smoke from her stack and trailed it behind, a dense, low-lying shadow.

"Look!" shouted one of the men into another's ear, and raised his arm to point. "We're beating the train!"

[Ill.u.s.tration: THE STEAM TURBINE-DRIVEN _VELOX_, OF THE BRITISH NAVY The fastest torpedo-boat destroyer.]

Sure enough, a pa.s.senger train running along the river's edge, the wheels spinning round, the locomotive throwing out clouds of smoke, was dropping behind. The train was being beaten by the boat. Quivering, throbbing with the tremendous effort, she dashed on, the water climbing her sides and lashing to spume at her stern.

"Time!" shouted several together, as the second pair of posts came in line, marking the finish of the mile. The word was pa.s.sed to the frantically struggling firemen and engineers below, while those on deck compared watches.

"One minute and thirty-two seconds," said one.

"Right," answered the others.

Then, as the wonderful yacht _Arrow_ gradually slowed down, they tried to realise the speed and to accustom themselves to the fact that they had made the fastest mile on record on water.

And so the _Arrow_, moving at the rate of forty-six miles an hour, followed the course of her ancestress, the _Clermont_, when she made her first long trip almost a hundred years before.

The _Clermont_ was the first practical steamboat, and the _Arrow_ the fastest, and so both were record-breakers. While there are not many points of resemblance between the first and the fastest boat, one is clearly the outgrowth of the other, but so vastly improved is the modern craft that it is hard to even trace its ancestry. The little _Arrow_ is a screw-driven vessel, and her reciprocating engines--that is, engines operated by the pulling and pushing power of the steam-driven pistons in cylinders--developed the power of 4,000 horses, equal to 32,000 men, when making her record-breaking run. All this enormous power was used to produce speed, there being practically no room left in the little 130-foot hull for anything but engines and boilers.

There is little difference, except in detail, between the _Arrow's_ machinery and an ordinary propeller tugboat. Her hull is very light for its strength, and it was so built as to slip easily through the water.

She has twin engines, each operating its own shaft and propeller. These are quadruple expansion. The steam, instead of being allowed to escape after doing its work in the first cylinder, is turned into a larger one and then successively into two more, so that all of its expansive power is used. After pa.s.sing through the four cylinders, the steam is condensed into water again by turning it into pipes around which circulates the cool water in which the vessel floats. The steam thus condensed to water is heated and pumped into the boiler, to be turned into steam, so the water has to do its work many times. All this saves weight and, therefore, power, for the lighter a vessel is the more easily she can be driven. The boilers save weight also by producing steam at the enormous pressure of 400 pounds to the square inch.

Steadily maintained pressure means power; the greater the pressure the more the power. It was the inventive skill of Charles D. Mosher, who has built many fast yachts, that enabled him to build engines and boilers of great power in proportion to their weight. It was the ability of the inventor to build boilers and engines of 4,000 horse-power compact and light enough to be carried in a vessel 130 feet long, of 12 feet 6 inches breadth, and 3 feet 6 inches depth, that made it possible for the _Arrow_ to go a mile in one minute and thirty-two seconds. The speed of the wonderful little American boat, however, was not the result of any new invention, but was due to the perfection of old methods.

In England, about five years before the _Arrow's_ achievement, a little torpedo-boat, scarcely bigger than a launch, set the whole world talking by travelling at the rate of thirty-nine and three-fourths miles an hour. The little craft seemed to disappear in the white smother of her wake, and those who watched the speed trial marvelled at the railroad speed she made. The _Turbina_--for that was the little record-breaker's name--was propelled by a new kind of engine, and her speed was all the more remarkable on that account. C.A. Parsons, the inventor of the engine, worked out the idea that inventors have been studying for a long time--since 1629, in fact--that is, the rotary principle, or the rolling movement without the up-and-down driving mechanism of the piston.

The _Turbina_ was driven by a number of steam-turbines that worked a good deal like the water-turbines that use the power of Niagara. Just as a water-wheel is driven by the weight or force of the water striking the blades or paddles of the wheel, so the force of the many jets of steam striking against the little wings makes the wheels of the steam-turbines revolve. If you take a card that has been cut to a circular shape and cut the edges so that little wings will be made, then blow on this winged edge, the card will revolve with a buzz; the Parsons steam-turbine works in the same way. A shaft bearing a number of steel disks or wheels, each having many wings set at an angle like the blades of a propeller, is enclosed by a drumlike casing. The disks at one end of the shaft are smaller than those at the other; the steam enters at the small end in a circle of jets that blow against the wings and set them and the whole shaft whirling. After pa.s.sing the first disk and its little vanes, the steam goes through the holes of an intervening fixed part.i.tion that deflects it so that it blows afresh on the second, and so on to the third and fourth, blowing upon a succession of wheels, each set larger than the preceding one. Each of Parsons's steam-turbine engines is a series of turbines put in a steel casing, so that they use every ounce of the expansive power of the steam.

It will be noticed that the little wind-turbine that you blow with your breath spins very rapidly; so, too, do the wheels spun by the steamy breath of the boilers, and Mr. Parsons found that the propeller fastened to the shaft of his engine revolved so fast that a vacuum was formed around the blades, and its work was not half done. So he lengthened his shaft and put three propellers on it, reducing the speed, and allowing all of the blades to catch the water strongly.

The _Turbina_, speeding like an express train, glided like a ghost over the water; the smoke poured from her stack and the cleft wave foamed at her prow, but there was little else to remind her inventor that 2,300 horse-power was being expended to drive her. There was no jar, no shock, no thumping of cylinders and pounding of rapidly revolving cranks; the motion of the engine was rotary, and the propeller shafts, spinning at 2,000 revolutions per minute, made no more vibration than a windmill whirling in the breeze.

To stop the _Turbina_ was an easy matter; Mr. Parsons had only to turn off the steam. But to make the vessel go backward another set of turbines was necessary, built to run the other way, and working on the same shaft. To reverse the direction, the steam was shut off the engines which revolved from right to left and turned on those designed to run backward, or from left to right. One set of the turbines revolved the propellers so that they pushed, and the other set, turning them the other way, pulled the vessel backward--one set revolving in a vacuum and doing no work, while the other supplied the power.

The Parsons turbine-engines have been used to propel torpedo-boats, fast yachts, and vessels built to carry pa.s.sengers across the English Channel, and recently it has been reported that two new transatlantic Cunarders are to be equipped with them.

[Ill.u.s.tration: THE ENGINES OF THE _ARROW_]

A few years after the Pilgrims sailed for the land of freedom in the tiny _Mayflower_ a man named Branca built a steam-turbine that worked in a crude way on the same principle as Parsons's modern giant. The pictures of this first steam-turbine show the head and shoulders of a bronze man set over the flaming brands of a wood fire; his metallic lungs are evidently filled with water, for a jet of steam spurts from his mouth and blows against the paddles of a horizontal turbine wheel, which, revolving, sets in motion some crude machinery.

There is nothing picturesque about the steel-tube lungs of the boilers used by Parsons in the _Turbina_ and the later boats built by him, and plain steel or copper pipes convey the steam to the whirling blades of the enclosed turbine wheels, but enormous power has been generated and marvellous speed gained. In the modern turbine a glowing coal fire, kept intensely hot by an artificial draft, has taken the place of the blazing sticks; the coils of steel tubes carrying the boiling water surrounded by flame replace the bronze-figure boiler, and the whirling, tightly jacketed turbine wheels, that use every ounce of pressure and save all the steam, to be condensed to water and used over again, have grown out of the crude machine invented by Branca.

As the engines of the _Arrow_ are but perfected copies of the engine that drove the _Clermont_, so the power of the _Turbina_ is derived from steam-motors that work on the same principle as the engine built by Branca in 1629, and his steam-turbine following the same old, old, ages old idea of the moss-covered, splashing, tireless water-wheel.

THE LIFE-SAVERS AND THEIR APPARATUS

Forming the outside boundary of Great South Bay, Long Island, a long row of sand-dunes faces the ocean. In summer groups of laughing bathers splash in the gentle surf at the foot of the low sand-hills, while the sun shines benignly over all. The irregular points of vessels' sails notch the horizon as they are swept along by the gentle summer breezes.

Old Ocean is in a playful mood, and even children sport in his waters.

After the last summer visitor has gone, and the little craft that sail over the shallow bay have been hauled up high and dry, the pavilions deserted and the bathing-houses boarded up, the beaches take on a new aspect. The sun shines with a cold gleam, and the surf has an angry snarl to it as it surges up the sandy slopes and then recedes, dragging the pebbles after it with a rattling sound. The outer line of sand-bars, which in summer breaks the blue sea into sunny ripples and flashing whitecaps, then churns the water into fury and grips with a mighty hold the keel of any vessel that is unlucky enough to be driven on them. When the keen winter winds whip through the beach gra.s.ses on the dunes and throw spiteful handfuls of cutting sand and spray; when the great waves pound the beach and the crested tops are blown off into vapour, then the life-saver patrolling the beach must be most vigilant.

All along the coast, from Maine to Florida, along the Gulf of Mexico, the Great Lakes, and the Pacific, these men patrol the beach as a policeman walks his beat. When the winds blow hardest and sleet adds cutting force to the gale, then the surfmen, whose business it is to save life regardless of their own comfort or safety, are most alert.

All day the wind whistled through the gra.s.ses and moaned round the corners of the life-saving station; the gusts were cold, damp, and penetrating. With the setting of the sun there was a lull, but when the patrols started out at eight o'clock, on their four-hours' tour of duty, the wind had risen again and was blowing with renewed force. Separating at the station, one surf man went east and the other west, following the line of the surf-beaten beach, each carrying on his back a recording clock in a leather case, and also several candle-like Coston lights and a wooden handle.

[Ill.u.s.tration: A LIFE-SAVING CREW DRILLING WITH BEACH APPARATUS Hauling in a breeches-buoy and a pa.s.senger.]

"Wind's blowing some," said one of the men, raising his voice above the howl of the blast.

"Hope nothing hits the bar to-night," the other answered. Then both trudged off in opposite directions.

With pea-coats b.u.t.toned tightly and sou'westers tied down securely, the surfmen fought the gale on their watch-tour of duty. At the end of his beat each man stopped to take a key attached to a post, and, inserting it in the clock, record the time of his visit at that spot, for by this means is an actual record kept of the movements of the patrol at all times.

With head bent low in deference to the force of the blast, and eyes narrowed to slits, the surfman searched the seething sea for the shadowy outlines of a vessel in trouble.

Perchance as he looked his eye caught the dark bulk of a ship in a sea of foam, or the faint lines of spars and rigging through the spume and frozen haze--the unmistakable signs of a vessel in distress. An instant's concentrated gaze to make sure, then, taking a Coston signal from his pocket and fitting it to the handle, he struck the end on the sole of his boot. Like a parlour match it caught fire and flared out a brilliant red light. This served to warn the crew of the vessel of their danger, or notified them that their distress was observed and that help was soon forthcoming; it also served, if the surfman was near enough to the station, to notify the lookout there of the ship in distress. If the distance was too great or the weather too thick, the patrol raced back with all possible speed to the station and reported what he had seen.

The patrol, through his long vigils under all kinds of weather conditions, learns every foot of his beat thoroughly, and is able to tell exactly how and where a stranded vessel lies, and whether she is likely to be forced over on to the beach or whether she will stick on the outer bar far beyond the reach of a line shot from sh.o.r.e.

In a few words spoken quickly and exactly to the point--for upon the accuracy of his report much depends--he tells the situation. For different conditions different apparatus is needed. The vessel reported one stormy winter's night struck on the shoal that runs parallel to the outer Long Island beach, far beyond the reach of a line from sh.o.r.e. Deep water lies on both sides of the bar, and after the shoal is pa.s.sed the broken water settles down a little and gathers speed for its rush for the beach. These conditions were favourable for surf-boat work, and as the surfman told his tale the keeper or captain of the crew decided what to do.

The crew ran the ever-ready surf-boat through the double doors of its house down the inclined plane to the beach. Resting in a carriage provided with a pair of broad-tired wheels, the light craft was hauled by its st.u.r.dy crew through the clinging sand and into the very teeth of the storm to the point nearest the wreck.

The surf rolled in with a roar that shook the ground; fringed with foam that showed even through that dense midnight darkness, the waves were hungry for their prey. Each breaker curved high above the heads of the men, and, receding, the undertow sucked at their feet and tried to drag them under. It did not seem possible that a boat could be launched in such a sea. With scarcely a word of command, however, every man, knowing from long practice his position and specific duties, took his station on either side of the buoyant craft and, rushing into the surf, launched her; climbing aboard, every man took his appointed place, while the keeper, a long steering-oar in his hands, stood at the stern. All pulled steadily, while the steersman, with a sweep of his oar, kept her head to the seas and with consummate skill and judgment avoided the most dangerous crests, until the first watery rampart was pa.s.sed. Adapting their stroke to the rough water, the six st.u.r.dy rowers propelled their twenty-five-foot unsinkable boat at good speed, though it seemed infinitely slow when they thought of the crew of the stranded vessel off in the darkness, helpless and hopeless. Each man wore a cork jacket, but in spite of their enc.u.mbrances they were marvellously active.

As is sometimes the case, before the surf-boat reached the distressed vessel she lurched over the bar and went driving for the beach.

The crew in the boat could do nothing, and the men aboard the ship were helpless. Climbing up into the rigging, the sailors waited for the vessel to strike the beach, and the life-savers put for sh.o.r.e again to get the apparatus needed for the new situation. To load the surf-boat with the wrecked, half-frozen crew of the stranded vessel, when there was none too much room for the oarsmen, and then encounter the fearful surf, was a method to be pursued only in case of dire need. To reach the wreck from sh.o.r.e was a much safer and surer method of saving life, not only for those on the vessel, but also for the surfmen.

The beach apparatus has received the greatest attention from inventors, since that part of the life-savers' outfit is depended upon to rescue the greatest number.

With a rush the surf-boat rolled in on a giant wave amid a smother of foam, and no sooner had her keel grated on the sand than her crew were out knee-deep in the swirling water and were dragging her up high and dry.