Steam jet

“ Besides a wind-pennant at one end of the bridge, assurance is made doubly sure by the turning on of a jet of steam in the mathematical centre of the extreme tip of the launching-stage. When the back-blown steam streams straight along the middle plank of the stage, the wind is "right."
The captain, from the bridge, lifts a small white flag as a signal to the wing-commander that all is ready. The latter nods to the pilot, who starts his engine at full speed, while two mechanicians, braced against cleats on the deck, hold back the tugging seaplane. ”

“ Jet aspirator, for inducing a mixed current of air and water or steam.
801. Steam jet pump; the steam enters by the central jet and causes a vacuum, into which the water rises by the branch pipe.
802. Insufflator for steam and air blast; used also as a petroleum injector, &c.
803 & 805. Spray jets; the liquid rises by gravity at the small vertical nozzles, and is driven in a spray or mist by a cross blast of air from the horizontal jets. ”

“ Hearing a roaring sound on my left, I turned aside to learn the cause; and there was a steam spring, or rather a jet of steam, that rushed out of the mountain with a loud and constant roaring. The noise and escape of steam were incessant, the steam coming out in a slanting direction, at least twenty feet in a direct line. The noise it made was greater than that of one of our largest steamship engines “blowing off.” ”

“ Crawshay, and while there applied his steam-jet to the blast furnaces. This gave an immense impetus to the manufacture of iron. The steam-jet caused the success of Stephenson's ‘Rocket’ engine on the Liverpool and Manchester railway in October 1829. Previously, on 6 Oct. this engine ran about twelve miles without interruption in about fifty-three minutes; when Gurney's discovery was first applied, a velocity of twenty-nine miles an hour was soon obtained. Gurney had applied the steam-jet to steamboats as early as 1824, when constructing his steam carriage, and on 6 Oct. ”

“ As steam, therefore, must be constantly drawn into the condenser, the jet of cold water which condenses the steam must be kept constantly playing. This jet, therefore, will not be worked by the valve alternately opening and closing, as in the single engine, but will be worked by a cock, the opening of which will be adjusted according to the quantity of cold water necessary to condense the steam. ”

“ So does steam act: the instant it can escape freely, it ceases to push. The entering steam, on the contrary, finds itself imprisoned. It pushes the piston, therefore, with all its strength and drives it to the other end of the cylinder. But then the rôles immediately change. The steam that hitherto has been pushing, escapes into the air and ceases to act, while on the other side a jet of steam rushes in from the boiler and begins to push in the contrary direction. ”

“ Thus, while the screw outside of the hull is applying the force continuously, the steam in the inside is driving the shafting with equal evenness and regularity.
The steam turbine does not appear to have by any means reached finality in its form, such questions as the angle of impact which the jet should make with the surface of the vane, and [Pg 126] the size of the orifice through which the steam should be ejected, being still debatable points. ”

“ He therefore introduced a stream of this material into a jet of steam, issuing freely into the air (which he hoped would moisten the powdered plaster sufficiently to cause it to set firmly into whatever form it collected) . The jet was directed against a splinter of wood. ”

“ The steam-engine may compete successfully with the wind as a propeller of vessels, whenever certainty of conveyance becomes important, as in the case of passage-boats upon lakes and rivers. But there are cases where steam becomes inapplicable to navigation. Upon the open ocean, although the safety of steamships has been fully tested, the vast quantity of fuel necessary in a long passage will prevent its use in distant voyages, and it is besides far less economic than the propulsion by means of sails. ”

“ And they run so close in-shore that the pilot has to be wary, and in some cases to emerge with a series of unearthly steam screeches, lest he step upon one of them with his great "horseshoe" of a ferry-boat. The steam-yacht is the most graceful as well as agile of the species, as certainly it ought to be when as much money is sometimes put into one as would buy a Raphael or build a Grecian temple. ”

“ When we got down to the landing-stage, the boatman said:
“Let me see, sir; was yours a steam-launch or a house-boat?”
On our informing him it was a double-sculling skiff, he seemed surprised.
We had a good deal of trouble with steam launches that morning. It was just before the Henley week, and they were going up in large numbers; some by themselves, some towing houseboats. I do hate steam launches: I suppose every rowing man does. I never see a steam launch but I feel I should like to lure it to a lonely part of the river, and there, in the silence and the solitude, strangle it. ”

“ They vary in size from 20 to 45 ft. in length, with speed from 6 to 10 miles an hour; in a measure they have displaced small steam launches as tenders for yachts, and in many places where no great degree of skill is required to run them; in fact, the ease of running and little time required to start a launch are the chief reasons of their popularity, in spite of the fact that they are noisy and malodorous.
The use of the steam yacht will, without doubt, continue to increase more rapidly than the sailing craft, but there is not the least probability that the latter will be superseded. ”

“ An equally powerful launch engine and boiler, together with a maximum stowage of fuel, will weigh about the same. There is, however, this disadvantage about the steam power, that it occupies the most valuable part of the vessel, taking away some eight or nine feet of the widest and most convenient part, and in a launch of twenty-four feet length, requiring such a power as we have been discussing, this is actually one-third of the total length of the vessel, and one-half of the passenger accommodation ”

“ The recent adaptation of the Parsons turbine for moderate speeds, already discussed, will doubtless pave the way for a much more general adoption of this form of propulsion in the yacht. Otherwise speed in the steam yacht is a doubtful advantage, for with reciprocating engines there is demanded a greater amount of space which could be better used for extra cabin room. Water-ballast and bilge-keels are used to a large extent, and steel has long since proved its worth for the making of the hull as well as many other features of the ship. ”

“ Like some of our popular authors who write sea stories that are not [110] sea stories, the average man firmly believes that steamships can and do sail, and it will take many years of pounding to get this idea out of the public's head. There are afloat steam vessels that can and do sail, but they are sailing vessels equipped with engines. In former times almost all ocean-going steam craft could work to leeward under canvas, but they, unlike the vessel of to-day, were heavily rigged, most of them carrying full sets of yards forward, and spreading many thousand feet of cloth. ”

“ But on one matter there is hardly any room for doubt, and that is that the best way to secure the benefit of the expansive power of steam is to permit it to escape from a pipe having a long series of orifices and to impinge upon a correspondingly numerous series of vanes, or, perhaps, upon a number of vanes arranged so that each one is long enough to receive the impact of many jets. ”

“ It was thus that man transformed the floating log, which he propelled with his feet, into a floating palace, driven thousands of miles across the greatest of oceans. Likewise he metamorphosed the puny stationary steam-engine into a demon that is more powerful than a thousand horses, and that rushes him across the broad spaces of the earth faster than the fastest deer.
Indeed, with the aeroplane, man has already done what was considered for countless ages as the acme of the impossible—he has learned to fly ”

“ The safe and rapid navigation by steamships may be regarded as an entirely new art due to the steam-engine. Already this art has permitted the establishment of prompt and regular communications across the arms of the sea, and on the great rivers of the old and new continents. It has made it possible to traverse savage regions where before we could scarcely penetrate. It has enabled us to carry the fruits of civilization over portions of the globe where they would else have been wanting for years. Steam navigation brings nearer together the most distant nations. ”

“ Before the end of the eighteenth century the first steps had been made to use the force of steam for driving ships. Before Trafalgar was fought steam engines had made their appearance in the royal dockyards. Then there was a pause; and many years passed by before steam propulsion was admitted to be a necessity for certain classes of war-vessels.
An interesting account of the state of design and practice as it existed on ship-board in the year of Queen Victoria’s accession is given by Commander Robert Otway, R.N., in his treatise on Steam Navigation. Low-pressure principles are still in vogue ”

“ There were two large bath rooms for the use of the after saloon passengers, and one three times as large as either of these two for the use of the ’tween deck passengers. She had seven watertight compartments and tanks capable of holding 64,000 gallons of water.
The Royal Charter, independently of her steam power, was a full-rigged ship, and was the first English vessel to adopt the American plan of double topsails on each mast. On her trial trips she averaged a speed of nine knots per hour with her propeller; and under canvas only, with a light N.N.E. wind, made fourteen knots per hour. ”

“ A sail or oar-propelled craft may be entirely free from vibration, whatever its speed, as the motions arising from water [Pg 277] are usually slow and deliberate. In fact, water in its calmer moods is an ideal medium to travel on, and the trouble begins only with the introduction of steam as motive force.
But even steam may be robbed of its power to annoy us. The steam-turbine has arrived. It works a screw propeller as smoothly as a dynamo, and at a speed that no cylinder engine could maintain for a minute without shaking itself to pieces. ”

“ The fact that you leave port with a certainty of getting to your destination on time, barring accidents, makes somewhat monotonous an event that otherwise containing a large element of chance induces a corresponding degree of excitement. There is probably no pastime so tiresome to an active man as steam yachting, especially if it be in familiar waters. A steam yacht is a lazy man's palace and an active man's prison. Except when there is a race or a difficult bit of navigation, I would as soon run a trolley car as a power boat. ”

“ However, this system of equations was solved only halfway through the 20th century. Therefore, Aviation pioneers largely used experimentation and employed less complex theoretical models in order to achieve their goals. As of the middle of 19th century, two new trends emerged based on the steam engine: the race to fly a lighter-than-air airship with engines and directional control, and the development of fixed-wing aircraft. Over time, the airplane began to take on a familiar shape. ”

“ Prior to the introduction of marine steam engines, the United States of America had no inconsiderable share of the world’s ocean traffic. No swifter ships raced with cargoes of tea from China to the Thames than the famous Baltimore clippers. No finer vessels crossed the Atlantic than the celebrated New York Packet Liners. It cannot be supposed that a people so enterprising as the Americans would make no attempt at ocean steam navigation. ”

“ For aerial motive-power, the principal requirements are: great power for weight with a fairly high factor of safety, compactness, reliability of operation under flying conditions, and safety from fire. Bulk and weight of steam-driven equipment apparently impose severe restrictions upon its practical development for present aircraft purposes, but who is willing to classify its future use as an absurdity?
Steam operation in small model airplanes is no innovation. ”

“ It's exploded by the beam, exploded into God knows what, and the result is your jet. It's a wonderful drive, with plenty of power for the purpose. But I think it forms a strong field of static over the whole shell of the ship, a kind of sphere of reflection that throws the emanations back into the ship from every point. Just my theory, but it explains why you get these physical changes, because that process of reflection gives a different ray than was observed in the ordinary shielded jet."
Gene nodded, asked: "Can I look at the jet assembly?" ”

“ We pass now to another type of steamship, which is endowed with as much distinctive character as the steam tug. The steam trawler may not be as smart as a steam yacht nor as fast as a torpedo destroyer; yet, for all that, she is able to encounter as bad weather and—size for size—is perhaps a good deal better sea-boat. ”

“ Old ladies, not accustomed to the river, are always intensely nervous of steam launches. I remember going up once from Staines to Windsor—a stretch of water peculiarly rich in these mechanical monstrosities—with a party containing three ladies of this description. It was very exciting. At the first glimpse of every steam launch that came in view, they insisted on landing and sitting down on the bank until it was out of sight again. ”