Donkey engine

“ A donkey-engine works a little crab having a large drum, the chain from which is connected with the main chain, and draws it round the multiple sheaves so as to take up the slack as fast as the main crab gives it out. The steam is always on the donkey, which is of such limited dimensions that it can do no injury to the chain even when its full power is in vain endeavoring to draw it any further ”

“ The donkey-engine worked—at a price—the price of constant attention and furious stoking—worked long enough to allow a wire-rope (it was made up of a funnel and a foremast-stay) to be led into the engine-room and made fast on the cylinder-cover of the forward engine. That rose easily enough, and was hauled through the skylight and on to the deck, many hands assisting the doubtful steam. Then came the tug of war, for it was necessary to get to the piston and the jammed piston-rod. ”

“ The second engineer—more reckless than resourceful—struck at random with a cold chisel into the cast-iron of the column, and a greasy, grey flake of metal flew from under the imprisoned foot of the connecting-rod, while the rod itself fell away slowly, and brought up with a thunderous clang somewhere in the dark of the crank-pit. The guides-plates above were still jammed fast in the guides, but the first blow had been struck. They spent the rest of the day grooming the donkey-engine, which stood immediately forward of the engine-room hatch. ”

“ The steam-signals are very peculiar; the engine never whistles, but indulges in a prolonged bellow, very like the hideous sounds emitted by that hideous semi-brute, yclept the Gong-Donkey, who used to haunt our race-courses some years ago—making weak-minded men start, and strong-minded women scream with his unearthly roaring. When I first heard the hoarse warning-note boom through the night, a shudder of reminiscence came over me, for I used to shrink from that awful creature with a repugnance such as I never felt for any other living thing. ”

“ We might add, it's never even half done—naturally. A donkey engine can work like that, but then it hasn't any brains. No man can work from sun to sun all summer and think at all or be good for anything at the end of it. ”

“ After scrambling along for some seven hundred feet, the young homesteaders beheld a donkey engine, puffing, snorting, and rocking on its skids from the exertion, close beside a spur of track upon which stood several flat cars.
When the log was abreast of one of them, the hauling cable was released. Others were adjusted, again the “donkey” puffed, and the section of tree trunk was pulled aboard.
“Only think of bringing in a log from where that one lay and loading it on a car without a man’s lifting a pound!” exclaimed Phil. “Wouldn’t it make the Eastern lumbermen open their eyes, though! ”

“ A little higher up, in another small lean-to, is a donkey engine that drives the “blower,” which produces blast for the forges and fires. This machine is vastly superior to the old-fashioned fan, and the speed of it is quite low; there is no danger of explosion or other rupture. It is a pleasure, since so much manufacturing plant is introduced to us from foreign countries — America, France and Germany — to reflect that the idea of the blower is English. ”

“ Croly was silent. It was plain enough to Larry what the matter was with the young man. The truth was he had at some time been temporarily in charge of a small portable or "donkey" engine, such as are used for hoisting purposes in stone quarries and in other out-of-door work, and he was incapable of recognizing the difference between the simple construction of such a machine and the complicated work in the great motive-power of the Tioga Iron Works. ”

“ In 1880 the lumber industry employed 1,687 persons, contributing 57 per cent of the value of all manufactures in the Territory. The eighties marked the initial use of power equipment in logging. The earliest logging locomotive was built at Marysville in 1883 and ran on a maple-wood track. The donkey engine appeared at Bellingham Bay in 1887, and soon, on Grays Harbor and lower Puget Sound, adaptations followed. First tried was the Dolbeer donkey, an upright steam engine with a capstan. ”

“ The screw engines, of 1,600 nominal horse-power, consist of four fixed horizontal cylinders, 4 feet stroke and 7 feet diameter, the two cylinders of each pair working opposite to each other on one crank.
In each boiler room are two donkey engines for supplying the boilers with water, and the main engines are also fitted with feed-pumps. Each of the donkey engines is capable of pumping water out of the ship, and of being used in case of fire. ”

“ The donkey engines hitched cables to stumps ashore, slid off their floats, hauled themselves puffing and grunting into the shadowy woods, black-bellied mechanical spiders drawing themselves along by a thread of twisted steel wire. A pile-driver crew with a two-ton steam hammer drove rows of sticks alongshore to enclose a booming ground. Another crew built a chute from tide-water to the first benchland. Men and powerful machinery directed with skill and energy wrought this transformation. ”

“ You notice the ends of the donkey’s skids are hewed like sled-runners, don’t you?”
“Yes.”
“Well, that’s so the engine can be pulled along. We simply hitch the cables to trees, the drums wind up, and the donkey pulls itself over the ground. When it is opposite the car on which it is to be loaded, we readjust the cables around other trees and it pulls itself aboard.”
“It’s wonderful,” exclaimed Ted. “You Westerners can certainly show the rest of the country how to do things in a big way.” ”

“ It is rendered necessary owing to the tendency to greatly increase pressure since the introduction of the triple expansion engine. An engine of 100 H.P., having a steam accumulator, gives the necessary power for working this, and advantage has been taken of the extra power to actuate a system of hydraulic hoists, winches and capstans, which are being substituted for the coal-devouring and often dangerous donkey boilers and steam winches, usually in use for this purpose. The hoists will also be applied to the larger latches in order to save manual labour. ”

“ In 1813 he, in conjunction with Mr. Bacon, secured a patent for a Polygonal printing machine, and in the same year invented and brought into use composition rollers, by which some of the greatest difficulties experienced at that time in printing by machinery were overcome. Among other inventions and mechanical contrivances of Donkin's are a very beautiful screw-cutting and dividing machine; an instrument to measure the velocity of the rotation of machinery; and a counting engine: for the two last gold medals were awarded by the Society of Arts. ”

“ Up to the present the waste has been so enormous in electric engines as compared with steam engines that steam has held its own in spite of its inferior strength. What I have invented is, to put it shortly, an electric engine in which there is hardly any waste; and we can now pump water, turn mill-stones, draw railway trains, and lift elevators, at a saving, in fuel and labor, of nearly seventy per cent, of the cost of steam. And,” added Conolly, glancing at Douglas, “as a motor of six-horsepower can be made to weigh less than thirty pounds, including fuel, flying is now perfectly feasible.” ”

“ Assuring himself that the gas gauge indicated at least several hours of fuel supply, and that he understood the controls for the lifting mechanism, Don operated the momentum starter. Its handle, rapidly rotated, gave a big, heavy wheel considerable momentum. Then, applying its control, he transmitted the power thus achieved to the engine and after several attempts the starter caused the charge in a cylinder to be ignited as the flywheel turned onto a point where a firing current passed into a charge of fuel mixture. ”

“ For one thing, it doesn’t mind damp, and the weather looks as if we should be in the clouds all the time. It’s a bonny little model and answers my hand like a tender-mouthed horse. The engine is a ten-cylinder rotary Robur working up to one hundred and seventy-five. It has all the modern improvements—enclosed fuselage, high-curved landing skids, brakes, gyroscopic steadiers, and three speeds, worked by an alteration of the angle of the planes upon the Venetian-blind principle. I took a shot-gun with me and a dozen cartridges filled with buck-shot. ”

“ I felt better as soon as I heard the steam, even though it was only in the donkey. Thinks I, there’s power, and it’s mine—a canful of steam to a typhoon. It was a chance to laugh at. Then I took the other engineers with me and we went below. The water there, full of cinders and trash, pouring through the gear 72 as she turned from side to side, made it look a pretty poor show. You see, the donkey wouldn’t work the pumps, for the coal and muck were sucked in. So I took a basket and got into the tank, holding the basket under the pump. ”

“ There was but one turn now between them; the rat took it.
Peace, with his hand on the machine, stopped and looked back, and at that, with one accord, donkey and cart and bicycle and man sped at each other. In an ornate zigzag with fancy steps they sped as if planning the dance from the foundation of the world. No one can dodge a shying donkey successfully unless it is known which way the donkey shies next. ”

“ Nearly a century passed between the making of the first practical engine and that one which now stands as the type of many thousands. But now every little saw-mill in the American woods could have, and finally did have, its little cheap, unscientific, powerful and non-vacuum engine, set up and worked without experience, and maintained in working order by an unskilled laborer. A thousand uses for steam grew out of this experiment of a Yankee who knew no better than to tempt fate with a high-pressure and speed and recklessness that has now become almost universal. ”

“ A sandy lane, golden with ruts, emerald with grasses, branched to it, and the rider got off his wheel and pushed it along the heavy ascent, unconscious that thereby he was saying his lines as they were written in the book, and playing the card that Fate had marked for the trick.
The donkey-cart gained—gained rapidly. Through sparse cedars, etched black on tawny sand, man and bicycle wound up-hill, and now he heard over the cliffs the boom of the breakers as he had heard it on Sunday when he came up with the Admiral. ”

“ We'll need no wings, of course, for with a small unit pointed vertically, we'll be able to support the car in the air. It will make possible a machine that will be able to fly in reverse and so come to a quick stop. It will steer us or it will supply us with electrical power, for we merely have to put a series of small metal bars about the circumference of the generator, and get a tremendously powerful engine. ”

“ So dizzy did I become that I wheeled Mac round and started in the opposite direction, the enemy bellowing, I calling, and the donkey braying to beat a fire-boat whistle. Finally, I heard the glad sound of approaching wheels from up the road, and at a glance saw a horse and buggy. As it came nearer, I distinguished a woman driving, and my heart sank. Surely she would not have the courage to venture into our very midst; she must soon turn round. A man might drive to our aid. ”

“ The machine looked as if it would work. Certainly if a big box-kite can not only sustain itself in the air but also support heavy flags, banners and even dummy figures, as is often done, a machine built on the same principle, only much larger, ought to hold up a man and a small engine.
“This is more like it,” said Jerry when Professor Dundlass was adjusting his motor. “It’s a wonder Noddy didn’t try something like this.”
“Oh, he wanted to be different,” observed Bob.
“Well, he was,” commented Ned dryly. ”

“ Animal strength and endurance are not an indefinite quantity; while the fireman grudges even the few short moments which are occupied by the inspanning of the team. In many towns, therefore, we find the mechanically propelled fire engine coming into favour. The power for working the pumps is now given a second duty of turning the driving-wheels. A parallel can be found in the steam-engine used for threshing-machines, which once had to be towed by horses, but now travels of itself, dragging machine and other vehicles behind it. ”

“ The insistent demand for direct connected units in the small and medium sizes, especially for direct current units, was the chief cause resulting in the rapid and high development of what is known as the "high speed automatic engine."
Increasing the engine speed means that more horse power is developed for any given cylinder dimensions, while reducing the speed of the generator involves that the machine must be larger for a given output, and in the case of an alternator more poles are required to obtain a given frequency, resulting in increased cost. ”

“ The most extraordinary thing about the whole damp business was the way the engine kept going. A real engine would have stopped dead the first time a wave came in and lay down beside it. But this rheumatic and asthmatic old bunch of junk, which some heartless pirate had sold to Algie for an engine, kept coughing and sputtering through it all. ”

“ A machine must be constructed that would do the work more quickly, more easily, and more cheaply.
A Frenchman named Denys Papin had built the first steam-engine with a piston. He had seen certain experiments that showed him how much strength there was in compressed air. He had noticed that air pressure could lift several men off their feet. His problem therefore was how best to compress the air, or, as it appeared to him, how to secure a vacuum. His experiments proved that he could do this by the use of [Pg 71] steam. He took a simple cylinder and fitted a piston into it. ”