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Scientific American Supplement, No. 481, March 21, 1885?试读：
THE RIGHI RAILROAD.
In the year 1864, the well-known geographer, Heinrich Keller, from Zurich, on ascending to the summit of the Righi Mountain, in the heart of Switzerland, discovered one of the finest panoramic displays of mountain scenery that he had ever witnessed. To his enthusiastic descriptions some lovers of nature in Zurich and Berne listened with much interest, and in the year 1865, Dr. Abel, Mr. Escher von der Luith, Aulic Councilor, Dr. Horner, and others, in connection with Keller himself, subscribed money to the amount of 2,000 marks ($500) for the purpose of building a hotel on the top of the mountain overlooking the view. This hotel was simple enough, being merely a hut such as is to be found in abundance in the Alps, and which are built by the German and Austrian Alpine Clubs. At present the old hotel is replaced by another and more comfortable building, which is rendered accessible by a railway that ascends the mountain. Mr. Riggenbach, director of the railway works at Olten, was the projector of this road, which was begun in 1869 and completed in 1871. Vitznau at Lucerne is the starting point. The ascent, which is at first gradual, soon increases one in four. After a quarter of an hour the train passes through a tunnel 240 feet in length, and over an iron bridge of the same length, by means of which the Schnurtobel, a deep gorge with picturesque waterfalls, is crossed. At Station Freibergen a beautiful mountain scene presents itself, and the eye rests upon the glittering, ice-covered ridge of the Jungfrau, the Monk, and the Eiger. Further up is station Kaltbad, where the road forks, and one branch runs to Scheideck. At about ten minutes from Kaltbad is the so-called "Kanzli" (4,770 feet), an open rotunda on a projecting rock, from which a magnificent view is obtained. The next station is Stoffelhohe, from which the railroad leads very near to the abyss on the way to Righi-Stoffel, and from this point it reaches its terminus (Righi-Kulin) in a few minutes. This is 5,905 feet above the sea, the loftiest and most northern point of the Righi group.FIG. 1.—STARTING POINT OF THE RIGHI RAILROAD.FIG. 2.—THE RIGHI RAILROAD.
The gauge of this railroad is the same as that of most ordinary ones. Between the rails runs a third broad and massive rail provided with teeth, which gear with a cogwheel under the locomotive. The train is propelled upward by steam power, while in its descent the speed is regulated by an ingenious mode of introducing atmospheric air into the cylinder. The carriage for the passengers is placed in both cases in front of the engine. The larger carriages have 54 seats, and the smaller 34. Only one is dispatched at a time. In case of accident, the train can be stopped almost instantaneously.FIG. 3.—NEW LOCOMOTIVE ON THE RIGHI RAILROAD.
We give herewith, from La Lumiere Electrique, several engravings illustrating the system. Fig. 1 shows the starting station. As may be seen on Figs. 2 and 3, the method selected for obtaining adhesion permits of ascending the steepest gradients, and that too with entire security.
HIGH SPEED STEAM ENGINE.
The use of rapidly rotating machinery in electric lighting has created a demand for engines running from 400 to 1,200 revolutions per minute, and capable of being coupled directly to a dynamo machine. We have already illustrated several forms of these engines, and now publish engravings of another in which the most noticeable feature is the employment of separate expansion valves and very short steam passages. Many high-speed engines labor under the well-grounded suspicion of being heavy steam users, and their want of economy often precludes their employment. Mr. Chandler, the inventor of the engine illustrated above, has therefore adopted a more elaborate arrangement of valves than ordinarily obtains in engines of this class, and claims that he gains thereby an additional economy of 33 per cent. in steam. The valves are cylindrical, and are driven by independent eccentrics, the spindle of the cut-off valve passing through the center of the main valve. The upper valve is exposed to the steam on its top face, and works in a cylinder with a groove cut around its inner surface. As soon as the lower edge of the valve passes below the bottom lip of the groove, the steam is cut off from the space between it and the main valve, which is fitted with packing rings and works over a latticed port. This port opens directly into the cylinder. The exhaust takes place chiefly through a port uncovered when the piston is approaching the end of its stroke. The remaining vapor left in the cylinder is exhausted under the lower edge of the main valve, until cushioning commences, and the steam from both upper and lower ports is discharged into the exhaust box shown in Fig. 2. The speed of the engine is controlled by a centrifugal governor and an equilibrium valve. This is a "dead face" valve, and when the engine is running empty it opens and closes many times per minute. The spindle on which the valve is mounted revolves with the governor pulley, and consequently never sticks. To prevent the small gland being jammed by unequal screwing up, the pressure is applied by a loose flange which is rounded at the part which presses against the gland. The governor is adjustable while the engine is running.IMPROVED HIGH SPEED STEAM ENGINE.
Another economy claimed for this engine is in the use of oil. The cranks and connecting rods work in a closed chamber, the lower part of which is filled with oil and water. The oil floats in a layer on the surface of the water, and at every revolution is splashed all over the working parts, including the interior of the cylinder, which it reaches through holes in the piston. The oil is maintained exactly at one level by a very ingenious arrangement. The bottom of the crank chamber communicates through a hole, C, with an outer box, which receives the water deposited by the exhaust steam. The level of this water is exactly determined by an overflow hole, B, which allows all excess above that level to pass into an elbow of the exhaust pipe, out of which it is licked by the passing steam and carried away. Thus, as the oil is gradually used the pressure of the water in the other leg of the hydrostatic balance raises the level of the remaining portion. When a fresh supply of oil is poured into the box, it forces out some of the water and descends very nearly to the level of the hole, B.
The engine is made with either one or two cylinders, and is, of course, single-acting. The pistons and connecting rods are of forged steel and phosphor-bronze. The following is a list of their sizes:
Single Engines.----------------------------------------------------------- Brake | | | | |Horsepower| Bore of | Revolutions| | |at 62 lb.| Cylinder. | per minute.| Height. |Floor Space.|Boiler | | | | |Pressure. | | | | |----------|-----------|------------|---------|------------- | in. | | in. | in. in. | 2¼ | 4 | 1,100 | 26 | 14 by 14 | 3½ | 5 | 1,000 | 28 | 14 " 15 | 6 | 6½ | 800 | 30 | 16 " 16 | 10 | 8 | 700 | 32 | 18 " 18 |----------------------------------------------------------- Double Engines.----------------------------------------------------------- Brake | | | | |Horsepower| Bore of | Revolutions| | |at 62 lb.| Cylinder. | per minute.| Height. |Floor Space.|Boiler | | | | |Pressure. | | | | |----------|-----------|------------|---------|------------- | in. | | in. | in. in. | 4½ | 4 | 1,100 | 26 | 14 by 20 | 7¼ | 5 | 1,000 | 28 | 14 " 20 | 12 | 6½ | 800 | 30 | 16 " 26 | 20 | 8 | 700 | 32 | 18 " 32 |-----------------------------------------------------------
The manufacturer is Mr. F.D. Bumstead, Hednesford, Staffordshire.—Engineering.
THE CHINESE PUMP.
If a glass tube about three feet in length, provided at its upper extremity with a valve that opens outwardly, and at its lower with one that opens inwardly, be dipped into water and given a series of up and down motions, the water will be seen to quickly rise therein and finally spurt out at the top. The explanation of the phenomenon is very simple. Upon immersing the tube in the water it fills as far as to the external level of the liquid, and the air is expelled from the interior. If the tube be suddenly raised without removing its lower extremity from the water, the valve will close, the water will rise with the tube, and, through the velocity it has acquired, will ascend far above its preceding level. Now, upon repeating the up and down motion of the tube in the water five or six times, the tube will be filled, and will expel the liquid every time that the vertical motion occurs.THE CHINESE PUMP.
We speak here of a glass tube, because with this the phenomenon may be observed. Any tube, of course, would produce the same results.
The manufacture of the apparatus is very simple. The tube is closed above or below, according to the system one desires to adopt, by means of a perforated cork. The valve is made of a piece of kid skin, which is fixed by means of a bent pin and a brass wire (Fig. 2). It is necessary to wet the skin in order that it may work properly and form a hermetic valve. The arrangement of the lower valve necessitates the use of a tube of considerable diameter (Fig. 1). We would advise the adoption of the arrangement shown in Fig. 2. Under such circumstances a tube half an inch in diameter and about 3 feet in length will answer very well.
It is better yet to simply use one's forefinger. The tube is taken in the right hand, as shown in Fig. 3, and the forefinger placed over the aperture. The finger should be wetted in order to perfect its adherence, and should not be pressed too hard against the mouth of the tube. It is only necessary to plunge the apparatus a few inches into the liquid and work it rapidly up and down, when the water will rise therein at every motion and spurt out of the top.
This is an easy way of constructing the Chinese Pump, which is found described in treatises upon hydraulics. Such a pump could not, of course, be economically used in practice on account of the friction of the column of water against a wide surface in the interior of the tube. It is necessary to consider the pistonless pump for what it is worth—an interesting experimental apparatus that any one can make for himself.—La Nature.
THE WATER CLOCK.
To the Editor of the Scientific American:
Referring to the clepsydra, or water clock, described and illustrated in the SCIENTIFIC AMERICAN SUPPLEMENT of December 20, 1884, it strikes me that the ingenious principle embodied in that interesting device could be put into a shape more modern and practical, doing away with some of its defects and insuring a greater degree of accuracy.Fig 1.
I would propose the construction given in the subjoined sketch, viz.: The drum, A (Figs. 1 and 3), is mounted in a yoke suspended in such a manner as to bring no unnecessary, but still sufficient, pressure on the friction roller, B, to cause it to revolve the friction cone, C (both cone and roller being of wood and, say, well rubbed with resin so as to increase adhesion).Fig 2.
The friction roller should be movable (on a screw thread), but so arranged that it can be fixed at any point, say by a lock nut, screw, clamp, or other simple means. It will be evident that, by shifting the roller, a greater or less speed of the cone can be effected, and as to the end of the cone's axis an index hand sweeping an ordinary clock face is attached, the speed of this index hand can be regulated to a nicety, in proportion to that of the drum. Of course, before fixing the size and proportion of the disk and cone, the number of revolutions of the drum in a given time must be ascertained by experiment. For instance, the drum being found to make 15 revolutions in 12 hours, the proportions would be:
Circumference of roller = 12 units.Circumference of middle part of cone = 15 units.
Or, the drum making 2½ revolutions in 3 hours, equal to 9 revolutions in 12 hours:
Circumference of roller = 12 units.Circumference of middle part of cone = 9 units.
Any slight inaccuracy can be compensated by the cone and disk device.
The drum, or cylinder, is caused to gradually revolve by a weight attached to an endless cord passing once around the drum. The latter might be varnished to prevent slipping. The weight should be provided with an automatic wedge, allowing it to be slipped along the cord in an upward direction, but preventing its descent. The weight is represented partly in section in the engraving. This weight should not be quite sufficient to revolve the drum, it being counterbalanced by the liquid raised in the chambers of the drum. The liquid, however, following its tendency to seek the lowest level, gradually runs back through the small hole, D, in the partitions, but is continually raised again, with the chamber it has just entered, by the weight slightly turning the cylinder as it (the weight) gradually gains advantage over the as gradually diminishing weight of each chamber raised.
As to the drum, the same might be constructed as follows, viz.: First solder the partitions into the cylinder, making them slanting or having the direction of chords of a circle (see Fig. 2). The end disks should be dish shaped, as shown. Place them on a level surface, apply heat, and melt some mastic or good sealing wax in the same. Then adjust the cylinder part, with its partitions, allowing it to sink into the slight depth of molten matter. In this way, or perhaps by employing a solution of rubber instead of the sealing wax, the chambers will be well isolated and not liable to leak. The water is then introduced through the center openings of the disks before hermetically sealing the drum to its axis.Fig. 3.
The revolving parts of the clock being nicely balanced, a pretty accurate timepiece, I should think, would be the result. It is needless to mention that the "winding" is effected by slipping the weight to its highest point.
Of course I am far from considering the above an "instrument of precision," but would rather look upon it in the light of a contrivance, interesting, perhaps, especially to amateur mechanics, as not presenting any particular difficulties of construction.ED. C. MAGNUS.Crefeld, January 5, 1885.
NEW TORPEDO.
We illustrate a new form of self-propelling and steering torpedo, designed and patented by Mr. Richard Paulson, of Boon Hills, Langwith, Notts. That torpedoes will play an important part in the next naval war is evident from the fact that great activity is being displayed by the various governments of the world in the construction of this weapon. Our own Government also has latterly paid great attention to this subject.
The methods hitherto proposed for propelling torpedoes have been by means of carbonic acid or other compressed gas carried by the torpedoes, and by means of electricity conveyed by a conductor leading from a controlling station to electrical apparatus carried by the torpedo. The first method has, to a considerable extent, failed on account of the inefficient way in which the compressed gas was employed to propel the torpedo. The second is open to the objection that by means of telephones placed in the water or by other signaling apparatus the torpedo can be heard approaching while yet at a considerable distance, and that a quick speeded dredger, kept ready for the purpose when any attack is expected, can be run between the torpedo and the controlling station and the conductor cut and the torpedo captured. The arrangements for steering by means of an electrical conductor from a controlling station are also open to the latter objection. The torpedo we now illustrate, in elevation in Fig. 1, and in plan in Fig. 2, is designed to obviate these objections, and possesses in addition other advantages which will be enumerated in the following description.
As stated above, the torpedo is self-propelling, the necessary energy being stored up in liquefied carbonic acid contained in a cylindrical vessel, E, carried by the torpedo. The vessel, E, communicates, by means of a small bent pipe extending nearly to its bottom, with a small chamber, B, the passage of the liquid being controlled by means of the cock or tap, F. The chamber, B, is in communication, by means of a small aperture, with the nozzle, G, of an injector, T, constructed on the ordinary principles. The liquid as it passes into the chamber, B, volatilizes, and the gas passes through the nozzle of the injector, which is surrounded by water in direct communication with the sea by means of the opening, W. The gas imparts its energy in the well-known manner to the water, being itself entirely or partially condensed, the water thus charged with carbonic acid gas being forced through the combining cone of the injector at a very high speed and pressure. Preferably the water is here divided into two streams, each driving a separate rotary motor or turbine, H, themselves driving twin screws or propellers, I. The motors exhaust into the hollow shafts, J, of the propellers, which are extended some distance beyond the propellers, so that the remaining energy of the water may be utilized to aid in propelling the torpedo on the well known principle of jet propulsion. The torpedo is preferably steered by means of the twin screws. A disk or other valve, A, is pivoted in an aperture in a diaphragm dividing the outlet of the injector, and is operated by means hereafter described, so as to diminish the stream of water on one side and increase it on the other, so that one motor, and consequently the corresponding propeller, is driven at a higher speed than the other, and so steers the torpedo.PAULSON'S SELF PROPELLING AND STEERING TORPEDO.
The valve, A, is operated automatically by the following arrangement: A mariner's compass, P, placed in the head of the torpedo has its needle connected to one pole of a powerful battery, D. A dial of non-magnetic material marked with the points of the compass is capable of being rotated by the connections shown. This dial carries two insulated studs, p, each electrically connected with one terminal of the coils of an electromagnet, K, whose other terminal is connected to the other pole of the battery. These two magnets are arranged on opposite sides of an armature fixed on a lever operating the disk or valve, A. Before launching the torpedo the dial is set, so that when the torpedo is steering direct for the object to be struck, or other desired point, one end of the needle of the compass, P, is between the steeds, p, but contact with neither, the needle of course pointing to the magnetic north. Should the torpedo however deviate from this course, the needle makes contact with one or other of the studs according to the direction in which the deviation takes place, and completes the circuit through the corresponding electromagnet, which attracts the armature and causes the disk to move, so as to diminish the supply of water to one motor and increase it to the other, and so cause the torpedo to again assume the required direction. Supposing the object which it is intended that the torpedo should strike be a large mass of iron, such as an ironclad, the needle will be attracted, and, making the corresponding contact, will cause the torpedo to be steered directly away from the object. In order to prevent this, a second compass, Q, is mounted in the front of the torpedo, and when attracted by a mass of iron, it short-circuits the battery, D, and thus prevents the armature being attracted, and consequently the torpedo from deviating. This needle is also capable of slight movement in a vertical plane, so that when passing over or under a mass of iron it is attracted downward or upward, and completes a circuit by means of the stops, which operate so as to explode the charge. The charge can also be exploded in the ordinary manner, viz., by means of the firing pin, X, when the torpedo runs into any solid object.
The depth at which the torpedo travels below the surface of the water is regulated by means of a flexible diaphragm, M, secured in the outer casing and connected to a rod sliding freely in fixed bearings. A spiral or other spring, O, is compressed between a color on the rod and an adjustable fixed nut, by which the tension of the spring is regulated so that the pressure of water on the diaphragm, A, when the torpedo is at the desired depth just counterbalances the pressure of the spring, the diaphragm being then flush with the outer casing. The rod is connected by suitable levers to two horizontal fins, S, pivoted one on either side of the torpedo, so that they shall be in equilibrium. Should the torpedo sink too deep or rise too high, the diaphragm will be depressed or extended, and will operate on the lines so as to cause the torpedo to ascend or descend as the case may be.
In order to avoid the risk of a spent torpedo destroying a friendly vessel, a valve is arranged in any suitable part of the outer casing, and is weighted or loaded with a spring in such a manner that when under way the pressure of the water keeps the valve closed, but when it
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