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CAPTAIN NORTON'S GOSSAMER CAR-
TRIDGE FOR SMOOTH-BORE GUNS.

THE above is a sketch of Captain Norton's gossa. mer cartridge, with spherical ball attached, intended to be used with smooth-bore shot guns, double or single, fitted with ordinary patent breeches, and so utilise arms of that description in case of emergency. The tapering form of the cartridge allows it to enter freely into the chamber so as to bring the small end as closely as possible to the communication from the nipple. Both the bullet and powder cartridge are covered with cotton net, and the stiffness necessary to preserve the general form of the completed cartridge is gained by pasting a strip of thin paper around it in such a manner as to leave each end exposed. Curtis and Harvey's improved "Large grain powder" has been found to be best suited to these cartridges, The net surrounding the bullet will retain any lubricating matter which may be preferred, and so facilitate loading and prevent leading of the barrel.

POUPARD'S IMPROVED WHEEL-SKID. MR. WILLIAM POUPARD, Engineer, of the Blackfriars-road, Southwark, has lately introduced an improved wheel-skid or shoe, which many persons think highly of. He forms his skid with a tail piece extending backward from the wheel-chamber so as to form an inclined guide or path for the wheel to follow on entering the skid. This tail piece may be carried entirely through to the front of the shoe, and he prefers to form it of wrought-iron or steel, while the body of the shoe may be made of cast or wrought-iron. He finds the best results to be obtained when the projecting tail piece is curved upwards, but he does not limit himself to so shaping it. Fig. 1 of the

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accompanying engravings is a side elevation of a wheel-skid or shoe, constructed according to his invention, and Fig. 2 is a section through the line ab of the same. A is the body of the skid or shoe, which is attached in the ordinary manner to a chain B; B' B' are sides or side pieces forming a chamber for the wheel; C is the tail piece, made by preference of steel or wrought-iron, and riveted or bolted to the body A, as shown by the dotted lines in Fig. 2. He prefers to form the tail piece of a curve to correspond with the contour of a wheel, but this shape can be varied without departing from the essential features of the invention. Fig. 3 shows a wheel just entering the skid; to provide for this raise the chain B, which brings the tail flush or nearly so with the ground, and allows the wheel to run in; let go the chain, and the wheel comes to rest in the skid. The improved skid is now being made in large quantities.

CHAPLIN'S STEERING APPARATUS.

AT a recent meeting of the Institution of Engi-
neers in Scotland, Mr. Neilson explained the con-
struction and working of Mr. Chaplin's steering
apparatus, several models of which were exhibited.
The improved steering apparatus is more par-
ticularly destined for flat-bottomed boats of light
draught for shallow waters. The steering is
effected by means of vertical plates disposed ob-
liquely at either end, or at both ends, of the
vessel, in the manner shown in Figs. 1 and 2,

FIC.I.

A

which are respectively an elevation and the plan of
the stern of a boat fitted with the plates. There are
two steering plates, 4, one on each side of the
vessel; and they work in vertical casings, the
positions of which are indicated by dotted lines at
B in the plan, Fig. 2. Each plate, 4, turns on a
joint at its front end, and when not required to
turn the vessel to the side it is on, is drawn up
within its casing. Independently of their peculiar
suitableness for flat-bottomed boats, these plates
have a greater control and act more quickly than
the ordinary rudder, from their being placed on
each side of the centre line of the vessel. A pair
of the plates at one end is sufficient for ordinary
requirements, whilst for intricate navigation a pair.
at each end may be used, to be actuated either
simultaneously or separately.

Mr. Downie asked, at what angle the steering
plates were set, and whether they had ever been
practically tried; and, if so, with what result?
Mr. Chaplin said that whilst various angles might
be adopted, he preferred that of 37° from the line
of the keel. The plates had been successfully
tried. He understood that seventeen boats were
being or about to be built in England with
steering plates on the same plan as that described,
being chiefly for the Government. On trying the
steering plates in a small boat, it was found that
when plates were acting on the same side at both
ends, the boat turned round on a radius equal to
its length. Another modification had been applied
to a vessel built by his firm, and sent to Java, con-
sisting of a simple conical shell oscillating on an
axis, a piece being cut out of the cone, and one
side or other being made to project as required;
but this was only suitable for small vessels, where
the apparatus was not to project through the
deck. The vessels which he mentioned as in
course of building were to draw 2 feet water, to
carry 1,000 men, and coals for a voyage of 50
miles. They were 220 to 240 feet long, and 35
to 40 feet beam, and almost perfectly flat. They
were, he understood, intended for the navigation of
the Ganges, and other rivers of India. The steering
apparatus was adapted as well for deep sea vessels
as for those of shallow draught; and for screw

vessels it was peculiarly fitted, for the screw could be fitted between the plates. In the event of any injury being sustained by one of the plates, it could be hoisted on deck without trouble and

repaired. If the steering plates were projected, one at each end of the vessel on opposite sides, and so as to be parallel to each other, the vessel would move in a lateral direction, and would be easily brought alongside of a pier.

AULD'S APPARATUS FOR SUPPLYING

STEAM BOILERS WITH WATER. MR. DAVID AULD, of Glasgow, Engineer, has just patented the "automatic mechanical arrangement for the efficient supplying of steam boilers with water, so as to ensure both a plentiful supply and certainty of action," which is represented in the annexed engravings. Fig. 1 is a partially sectional elevation of one modification of the apparatus. Fig. 2 is a partially sectional elevation of another modification of the apparatus, in which the several parts are arranged in a somewhat different manner. In the first arrangement, Fig. 1, the water for the supply of the boiler flows into the apparatus from an elevated tank or reservoir through the feed-pipe which opens into the valve chamber A, the efflux of the water being prevented by the clack-valve B, which closes the entrance to the valve chamber upon the occurrence of back pressure on the water. From the valve-box the water flows into the chamber C, and thence upwards into the cup-shaped chamber D above; the chamber C has two flanged tubular openings in the lower part, which serve to connect the apparatus to the steam-pipe E and the pipe F through which the water flows into the boiler G. The steam-pipe E is carried downwards into the boiler to the proper water level, and the waterpipe nearly to the bottom. The flow of steam through the pipe E is controlled by the valve H pressure of the steam within the boiler, and is which is pressed up against its seating by the prevented from falling away too far therefrom by the small bridge-piece I, which extends across the steam-pipe. The inlet to the pipe F is in like manner controlled by the valve J, which rests upon the bridge-piece K, during the time that the seating of the valve H is made conical at the water is flowing into the boiler. The tubular upper part to receive the lower extremity of the tube L, which passes up through the chamber C and D, and enters the copper globe M, terminating near its upper part. The tube L is fixed in position by the angular stays N, the lower bent extremities of which are bolted to the globe M, the bolts serving also to connect the globe to the short flanged pipe O, which slides loosely in the opening of the cap P of the chamber D. This cap is bolted to the flange of the chamber D, a diaphragm of india-rubber or other suitable flexible material being interposed between the faces of the flanges; the inner part of this diaphragm is held between the flanges of the pipe O. With this arrangement the water cannot escape, at the same time the pipe O, carrying the globe M, is free to slide up and down in the opening in the cap P. The globe M is formed in two parts which are bolted together, and at the upper part there is an eye by means of which it is attached to the chain Q, which is secured by a nut to the upper extremity of the segmental part of the balanced lever R. The segmental part of this lever is hollowed out like a grooved pulley, and at the central part of the lever there are laterally projecting knife edges similar to those of a scale beam. These knife edges rest upon a hardened steel plate, which is supported in slots made in the forked extremity of the pillar S; this pillar is carried upon an overhanging bracket cast on the side of the chamber C. To the outer part of the rocking lever R is fitted an adjustable counterweight T, which is fixed at the proper distance from the centre by the set screw U. Arching over the centre of the lever R and its supporting pillar is a bridge-piece , which is bolted to the lever R; this bridge-piece has a segmental slot made in it, in which are fitted two

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adjustable sliding stops W. These stops serve to check the lateral motion of the vertical swinging rod X, the lower end of which is carried on a stud fixed in one of the upwardly projecting ends of the pillar S; at the upper part of the rod is fixed the weight I, which is fastened thereto by a set screw. The weight T is fixed at such part of the lever R, so that it counterbalances the weight of the globe M and its appurtenances, together with a certain quantity of water in the globe, the upholding action being assisted by the overhanging weight Y on the rod X. As the water flows in from the supply-pipe and up into the globe M, when it reaches a predetermined height therein, the accumulated weight overcomes the gravity of the weight T, so that the lever R turns upon its centre, and the weight Y is thrown forward against the right-hand stop W; this action facilitates descent of the globe M, the short pipe O descending into the cup-shaped chamber D, at the same time the transverse pin at the lower part of the tube L comes in contact with the upper end of the spindle of the valve H, and the end of the tube enters the conical part of the tubular valve seating. The depression of the valve allows the steam to pass up the tube L into the globe M, its pressure causing the air valve Z, which is otherwise kept open for the egress of the air as the water flows up in the globe, to shut. The pressure of the steam on the surface of the water in the globe causes the valve J to open, and the water flows down the pipe Finto the boiler, the steam pressure serving also to close the valve B, which prevents the water being forced back through the feed-pipe. The inflowing of the water into the boiler continues until the globe M is so far reduced in weight that the counterpoise T'is sufficient to overcome its gravity and that of the weight Yin its overhanging position to the right of the centre of the lever R. When this takes place the globe M is raised by the motion of the lever R; the valves H and K are closed by the pressure of steam in the boiler, and the apparatus is again restored to its normal position. In this manner the due and effective feeding of the boiler is kept

up with unerring certainty, the filling or partial filling of the globe, and the discharge of its contents into the boiler being regulated according to the evaporative power of the boiler.

In the modification shown in Fig. 2 the water from the overhead tank or reservoir flows through the vertical feed-pipe a, the lower part of which is closed by the valve b, which opens into the cast-iron water-chamber c; this chamber has fitted in the upper part a cock d, for the discharge of air from the chamber as the water flows into it from the feed-pipe a. The lower part of the chamber c is cast with two flanged tubular openings, by which the apparatus is attached to the steam-pipe e and feed-pipe f, which project out above the boiler g. The steam and feed-pipes are fitted with valves h and j, which when open rest on the bridge-pieces i and k in manner similar to the arrangement of the corresponding parts in Fig. 1. The spindle of the valve h is prolonged upwards so as to enter the lower extremity of the tube l, which is fitted in the centre of the cylindrical vessel m, the upper part of the tube being held in position by the transverse stays n. The vessel m is by preference made of copper, and it has at the lower part a valve o, by means of which the contents escape into the chamber c when the valve spindle comes in contact with the bottom of the chamber. The vessel m is connected by means of the bridge-piece and rod p to the chain q, which is attached to the segmental extremity of the rocking lever r. The arrangement of this lever and the parts connected therewith are in all respects similar to the corresponding parts delineated in Fig. 1, and do not therefore require further description. The water from the tank or reservoir flows through the pipe a, and falls into the vessel m, which when nearly filled descends to the position shown in Fig. 2, the descent causing the valves h and o to open. The steam having now free ingress to the chamber c through the tube 1, its pressure closes the valve b, and acting upon the surface of the water, the valvej is opened, and the water flows into the boiler g through the pipe f. The flow of water continues

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until the weight of the vessel m is sufficiently reduced to admit of its being raised by the counterweight t, and thus restored to its normal position. The upward motion of the vessel m is followed by the opening of the valve b, and the closing of the valves h and j, and the self-acting operation of refilling the vessel m again goes on.

"By means of either of these modifications of my improved automatic feed apparatus," says Mr. Auld, "the due supply of water to boilers is most efficiently provided for, at the same time the simple arrangement of the several parts almost precludes the possibility of derangement."

CLAYTON'S

PATENT BRICK AND TILE

MACHINERY. WE have been invited, prior to the opening of the Smithfield Club Show, to inspect the working of some brick and tile machinery just completed by Messrs. H. Clayton and Co., in accordance with their several patents, and which machinery will be exhibited in motion during the continuance of the show, partly in Baker-street, and partly at Messrs. Clayton's Atlas Works, Upper Park Place (within a few minutes' walk of Baker-street), where alone the larger machines can be shown; the space procurable in the Baker-street building being too limited to admit of the exhibition of any of the machines, excepting one worked by hand power, but which is yet capable of turning out several hundred bricks an hour, whether solid or perforated, or a proportionate quantity of tiles, drain pipes, or similar articles. Before describing in detail the late improvements made in Messrs. H. Clayton and Co's machines, we think it well to observe that much credit is due to these gentlemen for their untiring perseverance in introducing modifications in the details of their machines, which extended practice has from time to time suggested, and is ever certain to suggest when there is any disposition to profit by experience. The principle of "leaving well enough alone" is doubtless, as regards many things, a very safe one, especially when changes are made, as it were,

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happened that prizes at our agricultural shows have been, perhaps unwittingly, awarded to those who have simply adopted Messrs. Clayton and Co.'s principles in the construction of their machines.

STEAM-SHIP ECONOMY.

TO THE EDITORS OF THE "MECHANICS' MAGAZINE." GENTLEMEN,-The objection to the formula which Mr. Atherton and the committee of Section G of the British Association have adopted as the test for economical performance in the steam mercantile navy, rests on the ground, first, that the

power of the displacement is improperly employed in place of the midship section-for that this is its purpose is now avowed by Mr. Atherton

hap-hazard for the sake of appearances, rather than viously to be being burned; but it has been comfrom any real desire to attain perfection; but this pletely overlooked that quite as much if not very principle would appear to be held in very light much more time and expense are involved in preesteem by Messrs. Clayton and Co., for notwith-paring that clay before it is made into bricks, this standing many hundreds of admirable machines preparation really necessitating great storage room, Lastly, we may as well state that Messrs. Clayton having during the last few years been constructed besides being very difficult, owing to the necessity & Co., besides manufacturing brick making and set to work by them, sufficiently perfect to for just so far drying the clay as to prevent it machines and brick factory fittings of all kinds satisfy the wants of those using them, we find adhering to the moulds, and yet not so far doing whatever, have successfully introduced a green crop every year changes made in their details which it as to deprive it altogether of a tendency to mower, which has given great satisfaction. The evince on the part of their constructors an abso cohesion amongst its particles. Space will not guide bars of this mower are very beautifully lute mastery over the subject which they have admit of our discussing the pros and cons of the formed in the shape of the letter Y, the upper made their special study-changes perhaps hardly dry and wet principles of brick making, but one portion not being solid as is usually the case, but noticeable by casual observers, but which, never point strikes us very forcibly, and that is that, consisting of two prongs with an open space theless, when cost of construction and durability from what we have seen the dry process requires between them, which allows of any matter which are concerned, are of the very highest importance, very powerful, heavy, and expensive machinery, becomes clogged to free itself immediately and so and deserve, especially at our hands, a careful in- costing to the tune of £3,000 or £1,000, for mak-preserve the cutting edge of the knife. We will vestigation and favourable notice. To make a ing say 20,000 bricks per day; whereas, for about only add that the maufacture of bricks by means machine which will sell, and to call it the best that one-sixth of this sum wet brick machinery of the various machines now made to facilitate it is made, is one thing; but to make a machine can be had of equal productive power. In other (not forgetting an ingenious one for ridding the really as well as it can be made before it is offered words, by the expenditure of the above sum, wet clay of stones by a process of straining the clay for sale, is quite another thing, but one which we brick machinery may be procured (even after through a comparatively finely perforated plate) fully believe Messrs. Clayton and Co. always allowing for additional labour) of five times the may be carried on as cleanly and as comfortably attempt to do. productive power of that for making bricks on as the manufacture of bread might be. Those the dry process. The problem Messrs. Clayton horrid red-headed and dusty, unrecognizable and Co. set themselves to work out was-to make individuals so frequently seen in ordinary brick a clean and perfect block of plastic clay; and the fields are fast going out of date, and their places product of their machines is assuredly the Q.E.D. supplied by others much more human in appearance, It would be quite impossible in a notice like the who can perform their labour without literally present to do more than hint at the various wallowing in the mire. machines Messrs. Clayton and Co. construct, suitable for manufacturers of bricks, either on a large or small scale, whether the machines be driven by steam, water, animal, or manual power, and whether intended for solid and hollow bricks alone, or for these as well as tiles, drain-pipes, and similar articles. Suffice it to say, that at the present time, having devoted considerable time to the subject and had much experience in fitting up brick manufactories, these gentlemen are enabled to supply all and every requisite for the thorough organisation of brick or similar clay ware works, including plans for the laying out of the works, the construction of the kilns, drying sheds, &o., and, moreover, advise on the selection of the sites for the erection of the works themselves. The production of "bricks, whole bricks and nothing but (good wet) bricks," has been the form of asseveration made by Messrs. Clayton and Co., any day these last five and twenty years, and as brick and tile mas ters they still stick to their "leather." Of machines lately ordered of Messrs. Clayton and Co., we may mention as many as twenty for the Government for India, while of those now exhibiting one is for Prince Bariadinsky, another for Prince Potenkin, and a third for Prince Demidoff for his mines in Siberia. There is also a large machine for Venice, and an order of some 20 machines is shortly to be completed for Bombay. With respect to special machines we must not omit to notice the new one for the manufacture of very large drain pipes or gas retorts. This machine is so constructed that the core or piston is not supported by any cross-bar, which would of course divide the stream of clay issuing from the machine, and which strain would not completely unite in a short distance, thus causing the pipes to crack; but the core or piston is suspended from a long rod attached to the upper part of the machine, thus leaving the clay undivided in its way through the die plate. Several of these machines are at work. We may also mention an ingenious machine for making extra finished bricks by plac ing ordinary bricks when in a moist state under pressure (about 3 tons) given by a bob lever and weight worked by hand, and which puts a fine polish on the surface of the bricks, besides stamp. ing any device upon them if required. The mould is in this case kept lubricated by a layer of cotton saturated with oil, being placed between two plates which together form the lower piston of the mould. We regret to learn that many of the improvements really invented and patented by Messrs. Clayton and Co., and so successfully introduced into their brick machinery, have like many other good things become imported into the productions of rival manufacturers so soon as their success has been established, and it has even

The points to which we now more especially desire to call the attention of our readers, relate first to the mole of driving the "roller" dies of the brick machines. Until recently these dies were driven continuously by means of straps, that is, they were in motion both when the clay was being passed through or rather between them, and also when the clay was stationary, which caused them to be unnecessarily worn by their rubbing against it. Besides this, the straps frequently slipped when accidentally wetted by the water used for Iubricating the surface of the dies, which caused the dies to travel at different speeds, and which, to some extent, was injurious to the perfect formation of the clay. The roller dies are now, however, driven by bevel-gearing, which is carefully boxed up in order to keep it clean, and which is actuated at proper intervals only (when the clay is in motion) by a cam and lever worked from the main shaft. Again, the dies which are covered with a porous material (kept moist and clean by water supplied both to its back and face) were formerly entirely so covered, about one inch both at top and bottom continually rubbing against the ends of the upper and lower fixed dies, and which caused comparatively rapid wear. This evil is now got over by encircling the roller dies with brass hoops at top and bottom, leaving the covering material only exactly deep enough to equal the thickness of the brick. Lastly, the foundation of these roller dies on which the coating is lapped is now made of white metal which does not oxydise, even although the machine lies idle for several months, but which would immediately result from the contact of the wet covering with the rollers were they of iron. We now pass on to improvements made for ensuring an uniform tension of the cutting wires. Formerly a rigid bar carried the end of these wires, which were quite independent of each other, and were tightened up by hand as equally as possible; now, however, nearly perfect uniformity is secured by fixing the carrying bar rigidly at one end only, that is, by bending it at that end in the form of a right angle, and then by the tension produced in the wires, bringing the other end (fitted with a friction roller) down about an inch until it rests upon a curved cross-bar, and upon which the friction roller travels as the wires are moved from side to side. Another matter which we may here mention is, that the small pinions used in these machines are cut out of solid blocks of wrought-iron, instead of being cast. The importance of this can perhaps be appreciated only by those who have worked machinery subject to the same rough usage as brick machinery is, and more especially when worked abroad or even in some home districts where repairs cannot be readily

effected.

Before concluding we would for a moment allude to the various attempts made to manufacture bricks from dry clay, by means of pressure. This mode of manufacture has been favourably looked upon in some quarters, from the idea that a considerable saving both in time and money could be made from the bricks requiring no drying pre

Even as

such factor being an imperfect factitious substitute thereof, a mere mathematical expedient in lieu of the reality. It is true, as suggested by Mr. Atherton, that the one will be as proper as the other, or that the midship sectional areas will vary exactly with the square of the cube root of the displacement, when the bodies immersed are similar in form and general proportions; but it is precisely because vessels are dissimilar in those respects that any formula is of any use at all beyond determining the comparative efficiency of propellers, engines, and boilers, instead of the comparative merits in the build of ships, and beyond ascertaining the effect of mere size. The formula in respect to its ostensible existence com mits through its accuracy a felo de se. to its remote and limited ability, there would exist no reason for preference, no difference in result between the formula in terms of midship section or in terms of displacement, if this statement of substitution and identity be accepted. That Mr. Atherton should have conceived the possibility of my "questioning the geometrical fact" on which the substitution is founded, could only have arisin from the printer's error, of making me say that the 3 power of displacement is a fictitious insteal of a factitious thing; but of course your eɔrrespondent does not require to be told that such substitution must necessarily be false and misleading, when the condition for the truth of the "geometrical fact" is wanting, namely, that the bodies be similar. So much for the erroneon-ness of the formula as being based on the midship section "in terms of the displacement."

But secondly, and principally, the objection to it rests on the ground of its being wholly inappro priate to the purposes which it professes to serve among merchant steam-vessels, namely, to test their carrying capacity in relation to speed and power; and this objection is equally valid, although we base the formula on the true midship section, instead of making the power of the displacement do duty for it. All the information that can be obtained by it is the velocity in re lation to power when the area of resistance is constant, or the area when the velocity is constant, of which the only item that is useful is the

velocity. The carrying capacity in combination, with speed is completely ignored, nor can it even be conjectured from the midship section, for the one might augment, or it might diminish, with the augmentation or with the diminution of the other. What, then, is the use of this formula as applied to merchant vessels in their character of I have been engaged during some time in transports of merchandise? Mr. Atherton says attempting to discover a plan for saving not ships, that I "admit the applicability of the formula but human life, when the destruction of a ship based on the midship section," which I certainly becomes inevitable. The small boats usually found do, but only for the pupose I stated, namely, of even in large vessels are, in nine cases out of ten, obtaining the comparative worth of the lines of useless. They founder, or are dashed to pieces vessels through the velocities attained with a against the ship, as soon as they are filled with definite amount of power, and consequently the human beings. The plan which I propose as a comparative worth of merchant-ships, in their substitute for existing arrangements, is applicable character as passenger vessels primarily. Here to all existing ships, without incurring any great the useful effect contemplated is merely velocity, expense. I would suggest that every ship should and this the formula indicates, and this alone; but be furnished with an upper moveable deck, which if we would view it and value it conjointly with could be unshipped, and made to answer the purthe amount of goods carried, we must approxi-pose of a raft. This deck-raft, if I may so term it, mate thereto through a formula based on the dis- would be fastened to the ship only by means of placement simply, as I have heretofore explained. screw-bolts, which could be easily removed, but as Indeed I cannot think that the author of the for- the masts would pass through it, it would at all mula under animadversion, whoever he is, intended other times form an immoveable portion of the merely to express the midship section in terms of vessel. The bulwarks might be connected with the displacement," but wished, although making a the upper deck, but the rigging would be fastened muddle of the thing, to mix up with it the element to the ship. After losing all hopes of saving a of tonnage. Mr. Atherton does not attempt to vessel, the masts and rigging would be cut away, defend the appropriativeness of the formula; the screw-bolts removed, and the deck raft entirely would it not then have been as well to have disconnected from the hull of the vessel; the acknowledged at once that it is indefensible? I waves would soon set it afloat, and it might prove beg to assure him that I intended exoneration, a life raft capable of saving hundreds of lives. In and not an inuendo, by saying that from what I the loss of the Royal Charter, we have a melancould understand he was not the author of it. It choly instance of the want of provision for saving seems I might have learnt in his own writings life; and such tragedies may be soon repeated, for that he has disclaimed any such honour, but I cool heads and clear judgments are not always have not had the pleasure of other acquaintance the attributes of commanders of vessels. The form with them than through your pages. of a vessel causes it, on drifting, to strike aground a few hundred feet from the shore; and it is in that narrow space of water that thousands of lives are annually lost. Is it too much to assert that had the Royal Charter been furnished with a deckraft none on board would have perished? I think not. Several hours passed between the ship being run on shore and her breaking up. This would have allowed the raft to be unshipped, and the passengers to be transferred to it; when being flat, it would have been thrown by the waves within a few minutes high upon the beach.

then let the attempt be made to scuttle it during | a gale, fifty miles S. W. of the Land's-end, and if all attempts to do so should fail, then, and not till then, will Mr. Atherton have proved the practicability of adapting his invention for purposes of naval warfare.

Yours, &c., BENJAMIN CHeverton.

UNSINKABLE SHIPS AND RAFTS. TO THE EDITORS OF THE "MECHANICS' MAGAZINE."

GENTLEMEN, Mr. Atherton evidently imagines that in proposing to construct unsinkable ships he has made a valuable discovery. He seems, however, to be satisfied with the principle, apart from any consideration as to the obstacle which may stand in the way of its being practically applied; and he leaves to others the task of maturing the invention, so that vessels may be built which will defy shot and shell, wind and waves. I presume that those who will succeed in fulfilling these requirements will deserve as much credit as the inventor; possibly, however, Mr. Atherton will compete for the prize which is to be offered by the Society of Arts, and consequently may succeed in keeping all the credit to himself-and which he will most certainly deserve. So far, the invention has been but vaguely defined. In the first place, we are favoured with a ship which is to be a solid mass up to the water line; and that such a ship would float under all circumstances, there is no room to doubt; but what have we to prevent it from floating keel upwards? and from sending its dead and living cargo into the depths of the ocean? We have an answer, or that which may be supposed to be intended as an answer, from Mr. Atherton, in the form of an explanation, in the last number of the MECHANICS' MAGAZINE ;-the machinery is to be placed below the water line. This I suppose includes the boilers, fuel, &c. Perhaps it will also be found essential to make room considerably below the water line for the powder magazine; for shot and shell; and by this time we shall find the ship, the solid mass, tolerably well ballasted. But will he not admit the necessity of scooping out of the mass a spacious "cock-pit," in which the surgeon will be in no danger of having his head knocked off by a stray shot, while amputating the limb of a naval hero? Clearly there is no necessity for building new ships before adopting Mr. Atherton's invention. In order to test its value, all that is required is to select a line-of-battle ship-an old hulk; let the hold up to the water line be filled up with some light, water and fire-proof substance, with the exception of the spaces above enumerated;

In the case of large vessels, more especially steamers, I would construct the deck-raft in two sections, the division being near the funnel. This would give great facilities for launching it on the waves, and in many instances one section only would be required. The raft should, of course, be constructed as firmly as any portion of the vessel, but as it would form the real deck, the planking beneath might be thinner than usual. As, however, it would be essential that water should never

prove invaluable to many brave fellows who pass their lives on the ocean, too many of whom find in it a grave.

I remain, gentlemen, very respectfully, JOHN DE LA HAYE. Perth, November 18th 1859.

SAILING.

TO THE EDITORS OF THE "MECHANICS' MAGAZINE." GENTLEMEN,-Suppose two ships sailing in the same direction, with a strong gale on the quarter, one of the old form aptly described as being built by the mile and cut in lengths, the other of the modern clipper form. The former is under reduced sail and goes ten knots, the latter carries on and goes eighteen knots; the spars of the former bend as though another foot of sail would break them, the latter shakes out the reefs as she gathers way, and sail is added without danger to the spars. If the pressure of wind at the time is ten pounds per square foot of stationary surface, the pressure on the former ship's sails would be about six pounds per foot, while the clipper's sails would only have to sustain 16 pounds per foot, her speed reducing the actuating force to that extent; and this accounts for the fact that captains of clipper ships caring such a press of sail as they do in favourable gales, every foot of canvas added reducing the surface pressure, and adding to the speed without unduly straining the ship.

Two yachts of equal dimensions, differing in form, but of equal spread of canvas, sail a match. It is generally supposed that such a match is a fair one, and that they both carry the same power. This, however, is a mistake, and it is, in most cases, very unfair to the fleetest of the two, for she has to win the match with less power than the slower vessel, for the reason shown above.

Supposing, then, that ships are provided with ample canvas for favourable winds, with steampower for calms and light winds, still there remains the fact that heavy adverse gales may and do arise when steam and sails are almost useless. When I heard of the wreck of the Royal Charter, I pictured to myself a large ship in this very position; yet I could not help thinking that the hurricane which proved such an enemy to her might, by suitable means, have been converted into a friend.

Reverting to my first illustration, it is evident that the two vessels can carry canvas in the proportion of 1 to 3.75 with the same amount of strain on each, and the effective horse-power used in propelling two ships may be represented as 1,000 in the case of the slow vessel, and 1,800 in that of the clipper.

It is evident, therefore, that to obtain great power from the wind a certain amount of speed of the propelled surface is necessary. A ship in a hurricane with a dangerous shore under her lee cannot, as ordinarily rigged, carry sufficient sail to realise the power to gain an offing; yet power is to be had in abundance, and to apply this power

capable of ready hoisting and lowering, and geared to either screw or paddle-wheels, by which an immense and cheap power can be applied, eclipsing both steam and ordinary sails, when working to windward in heavy gales.

percolate between the two, I would propose to fasten some waterproof substance on the under part of the deck-raft. Vulcanized india-rubber, or kamptulicon, would be unquestionably the best, but the cost might be too great; and in that case, a rope matting saturated with tar might be used-revolving vertical wind-screws should be used or better still some light, cheap, water and fireproof substance, not yet discovered; but in the discovery of which we may receive some valuable assistance from the Council of the Society of Arts. Such a deck would be valuable, independent of its ever being required for saving life, as it would muffle the sounds caused by dragging chains and heavy weights-sounds so disagreeable to passengers, as any one who has passed a few nights at sea during a gale can testify. Various modes of constructing the raft will suggest themselves to shipbuilders, so that it might be converted into a ship should occasion require; and I hope that the idea will not be altogether discarded unless a more effectual plan can be devised for preventing the loss of so many valuable lives, frequently within

a stone's throw of terra-firma.

I believe Mr. Atherton's invention admirably adapted for fishing-boats, but in its present form, it is not worth much. If his ambition will condescend to take a sufficiently humble flight, and mature his invention, he will accomplish as much as if he had built an unsinkable frigate. It would

I have made some calculations upon the subject, and I think that no vessel thus fitted need be lost on a lee shore; in fact, a head-wind may be regarded as a very valuable propelling power, instead of a hindrance to a vessel's progress. I propose that the wind-screws should be made to take a convenient form for housing on deck when

not in use.

Suppose the Great Eastern to be thus fitted, I should make the radius of the wind-screw 40 feet, the pitch 120 feet; the screw could be lowered on

deck and housed in a house built across the deck

In a wind

81 feet long by 10 feet wide and 6 feet high, and could be hoisted in about 15 minutes. producing a pressure of 33 lbs. per square foot of stationary surface, every square foot of this screw

Many persons would call them wind-mills, but the word mill is inapplicable.

would produce about of a horse-power, and, as the Great Eastern could conveniently carry 3 such screws, from 5,000 to 8,000 horse-power could be obtained without burning a pound of coal.

I do not claim to be the inventor of" windmills on deck," the plan was patented so far back as 1709, and most of the subsequent patents (many of them very absurd) are therefore wanting in novelty, and void. The plan is open to all, the wind is a cheap motor, the safety of lives and ships is important, and I believe the adoption of this mode of using adverse strong winds would greatly reduce the chances of shipwreck, and with it the cost of insurance, and tend to increase the speed and economy of transit.

I am, Gentlemen, your obedient servant, 1 Clifford's-inn, Nov. 22, 1859.

T. MOY.

MEANS OF RETARDING RAILWAY

TRAINS.

TO THE EDITORS OF THE "MECHANICS' MAGAZINE."

GENTLEMEN,-In last weeks MECHANICS' MAGAZINE a letter appeared from Mr. Alexander Allan of the Scottish Central Railway, disclaiming the invention of the throttle in the blast pipe of the Locomotive Engine, and awarding the whole merit of its introd ction into this country to Mr. Rudolph Bodmer, of London. I cannot suffer that statement to pass without calling attention to a letter I wrote on the subject, gned "A Constant Reader," and which appeared in vol. 14, of the MECHANICS' MAGAZINE, No. 383, and dared December 11th, 1830. As many of your readers may not be in possession of the Magazine of that date I give copy of the letter:

"MEANS OF STOPPING LOCOMOTIVE ENGINES.

"SIR,-A few years since an accident happened at a colliery where I was the engineer; the break that runs up against the fly wheel broke, and it was not in my power to stop the engine in time. A few weeks after I put a throttle valve to the eduction or waste pipe, where the steam escapes, and by shutting both throttle valves together I managed to stop the engine immediately. The moment the steam in the cylinder could not get out, the engine ceased to move. Now, Mr. Editor, might not a contrivance of a similar kind prevent such melancholy accidents as that which befel the lamented Mr. Huskisson at the opening of the Liverpool and Manchester Railway. I am aware of the momentum acquired by an engine in motion, and I do not say the means here suggested would meet that difficulty, but we are bound to do all we can to lessen the chances of such disasters; and I am sure that were the steam only brought under such perfect subordination, those chances would be reduced tenfold. Your insertion of these brief hints will much oblige,

"Your obedient servant,

"A CONSTANT READER." Since the above letter appeared the adaptation of the throttle valve to the blast pipe has been patented by Mr. Booth, of the Liverpool and Manchester Railway, whose attention I then called to the invention; it appears also to have been since re-patented by Mr. Bodmer and Mr. Allan. Neither the invention nor its application is due to any of the three before-named gentlemen, but to your obedient servant, J. HOPKINSON, Engineer.

Britannia Works, Huddersfield.

STEAM ROCKET PROPELLER. TO THE EDITORS OF THE "MECHANICS' MAGAZINE." GENTLEMEN,-Will you allow me a little space to reply to inquiries of readers of the MECHANICS' MAGAZINE?

The steam rocket at a pressure of 1000 lbs. per inch will, I believe, give more propelling power than any marine engine from the same amount of fuel. The rocket tube might be formed of the required strength by being made of small diameter, and of a roll of metal welded together, or of thin tubes fitting tightly one over another, and to allow for the expansion of the metal each tube should be put on hot. The recoil of a gun is caused much more by the velocity and expansion of the discharge than from its immense pressure. Steam at

one tenth the pressure has at least ten times the velocity and expansion of the gases from gunpowder; this difference arises from the greater elasticity of steam. Atmospheric air under the same pressure would have greater velocity and expansion, although not approaching to that of steam, water on the other hand being non-elastic would have less velocity, and, of course, no expansion, and therefore a discharge of water is greatly inferior to steam as a method of propulsion. Inattention to the differences in velocities of gases and their expansion is, I believe, one of the principal reasons why carbonic acid has not hitherto been worked to a successful result as a motive power. A steam rocket of 1 oz. propels a boat of 7 ft laden with 20 lbs. With a properly constructed vessel I have no doubt a speed of 30 miles per hour may be obtained in smooth water.-Yours &c., JAMES PARKER.

Camberwell.

LONDON SEWAGE.

THE following letter explains itself, and deserves attention:

TO THE EDITOR OF THE 66 TIMES." SIR,-As none of your correspondents have questioned the statements made by Mr. George Shepherd, C.E., in his letter on the value of sewage to the farmers, inserted in the Times of the 16th inst., I would be glad if you would allow me to make a few observations. The matter is important inasmuch as the determination of what is to be done with the sewage entirely depends on its value.

Mr. Shepherd says: "It is a fact that 750 tons of the rich sewage of London can be delivered to a distance of 100 miles round London, and on. every farm included in that area, at a less cost than the farmer is now paying for 1 ton of guano, while the 750 tons, of sewage contains more fertilizing matter than 5 tons of guano."

If this were really the case our prospects for the utilization of sewage as it is-by the farmers would be very hopeful indeed, but I am sorry to say it is far from the truth. According to Drs. Hoffman and Witt, whose report on the nature, properties, and value of sewage, is the latest and best (published in the blue-book on the main drainage), the value of 100 tons of London sewage is only 17s. 7d. or a fraction over 2d. per ton, so that it would require 1,700 tons of sewage to replace 1 ton of guano. It follows from this that instead of 750 tons of sewage containing more fertilizing matter than 5 tons of guano, it only contains matter equal to about 9 cwt. The question which next arises is, at what rate or price can 1,700 tons of London sewage be delivered to the farmer at say 10 or 20 miles distance so as to replace 1 ton of guano which costs him £15 per ton? Again, can the sewage be delivered to the farmers at less than 2d. per ton, at say 10, 15, or 20 miles from London? If so, for how much per ton can it be delivered? There are other very pertinent questions which might here be put, but I do not wish to take up too much of your space; and besides, it will be as well to obtain satisfactory answers to the above before proceeding further. sary to repeat that this subject is very important, but the adoption of sewage as a manure must after all depend on its value as a fertilizer, and on what it can be delivered to the farmer for. I remain, yours, &c.

Greenwich, Nov. 22, 1859.

It is neces

C. F. O. GLASSFORD.

The Vicomte Marie de Botherel, who died the other day in very straightened circumstances at Dinan, formerly possessed a large fortune, but got rid of it all through his unquenchable love for commercial speculations. His chief folly was the building of an inmense establishment, including 15 kitchens, and starting omnibus restaurants: 12 of these vehicles carried hot viands, and 12 cold, all over the city; while 24 more supplied all Paris-or would have done so-with wine and liqueurs. He lost all his fortune by this freak except 260,000 fr., and this he got rid of in a very short time as a wine merchant on a gigantic scale. He has left behind him a work, in 4 vols., on "Human Infirmities!!"

NOTICES.

The MECHANICS' MAGAZINE will be sent free by post to all subscribers of £1 1s. 8d., annually, payable in advance. Post Office Orders to be made payable to R. A. Brooman, at the Post Office, Fleet Street, London, E.C.

THE APPEAL.

SINCE our last notice on this subject the following sums have from time to time been received, viz., T. B., £1; J. N., 10s.; J. T. 5s, ; H. O., 2s. 6d. ; H. B., 2s. 6d. For each and all of these we have to express the warm thanks of the receiver.

[ADVERTISEMENT.]

66

TO THE EDITORS OF THE MECHANICS' MAGAZINE." Scottish Central Railway, Locomotive Department, Perth, November 21, 1859.

DEAR SIRS,-Will you oblige me by inserting in your two next numbers that I do not claim the Originality of the Throttle Valve in the Blast Pipes in Locomotive Engines, as a means of retarding railway trains, though patented by me: for, since I did so, I have found it previously patented by Mr. RUDOLPH BODMER, of London, to whom any merit is due in introducing it in this country. I am, dear Sirs, yours truly,

ALEX. ALLAN.

Law Cases.

CURTAIN'S PATENT CARPETS.

COURT OF EXCHEQUER, Nov. 30. (Sitting at Nisi
Prius, at Westminster, before the Lord Chief
Baron and a Special Jury.)

CURTAIN v. CROSSLEY AND OTHERS.

Mr. Huddleston, Q.C., Mr. McNamara, and Mr. George Shaw were counsel for the plaintiff. Mr. Atherton, Q.C., Mr. Montague Smith, Q.C., Mr. Grove, Q.C., and Mr. Aston appeared for the defendants.

This was an action brought by the plaintiff, who is the patentee of certain improvements in the manufacture of carpets, for an infringement of his patent by the defendants, who are the well known carpet manufacturers at Halifax, in Yorkshire. The infringement complained of was the using by the defendants of a wire with a bladed end for cutting the pile of Brussels pile carpets in the course of their manufacture in the manner pointed out by the specification of the plaintiff's patent. It was shown that the old method of cutting the pile could not be applied to power looms, and there was no question as to the fact of the defendants having used the bladed wire. For the defence it was proved that wire constructed on the same principle as that used by the plaintiff had been used in the manufacture of pile carpets, velvet, and velvet lace anterior to the date of his patent. An extract was read from the Dictionnaire des

Arts, published in Paris prior to the plaintiff's patent, and sold in London, describing the raising of the pile of Gobelin tapestry by a process similar to that employed by the plaintiff in his manufac tures under his patent.

After Mr. Atherton had summed up his evidence, and Mr. Huddleston replied upon the whole case,

The Lord Chief Baron, in the course of his summing up, told the jury that if they believed the witnesses called for the defendants, they must find their verdict for them.

The Jury found a verdict for the defendants.

TUCK'S PATENT PISTON-PACKING. COURT OF QUEEN'S BENCH. Nov. 30.-SECOND COURT. (Before Mr. Justice Blackburn and a Special Jury.)

The Court was occupied the whole day in the trial of " Tuck e. Silvers," for the infringment of a patent for packing the piston-box of steam engines.

Only six special jurors answered, and the remainder of the panel were fined 5. each for non

attendance.

and Mr. Hindmarch appeared as counsel in the Mr. Bovill, Mr. Lush, Mr. Wilde, Mr. Webster,

case.

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