brown hematite or hydrated peroxide of iron, found as bog ore in beds in Bohemia, Poland, and Russia; carbonate of iron, generally found with the coal measures; and nearly pure iron, as in the masses, of meteoric origin, which have been discovered in various parts of the .world.

England possesses iron ores in exhaustless abundance, and peculiar and remarkable advantages for the manufacture of iron. These ores occur in carboniferous limestone, in the coal measures and the lias. The ores of the carboniferous limestone are found in parts of Wales, and in the North of England, and in one place at the Park and Roanhead Mines you may proceed 400 to 500 feet in either direction in one solid mass of this

valuable substance, and nothing has as yet been seen of the bottom of it. The ironstones of the coal measures are found in Yorkshire, Derbyshire, Staffordshire, and Scotland. The ores of the oolite are found in Yorkshire and Northamptonshire. These iron mines are well-known; but it is not so widely known that there are vast deposits of iron ore of great richness in Ireland as yet but little worked. In France iron ores are also abundant, but the scarcity of coal restricts their manufacture. They are found in the departments of the Yonne, the Meuse, the Moselle, and extending from the Pas de Calais on the north to the Jura on the south. In Prussia, Austria, Belgium, on the Vistula and the Oder, at Charleroi and Liege, in Upper Silesia, Styria, Moravia, and Hungary, valuable and extensive deposits exist. In Sweden iron has long been made, and until recently it has been unrivalled. The iron ores in America are numerous, and are scattered over the whole country. They are worked in New England, New York, New Jersey, Pennsylvania, and vast deposits exist in the great valley of the Mississippi. In Nova Scotia some of the richest ores yet discovered occur in exhaustless abundance. Other countries also are well supplied with iron ores, and the whole surface of the globe scems interlaid and interstratified with this useful and indispensable material.

For a description of the different methods of reducing these ores, and converting them into the different kinds and shapes of iron and steel used in commerce, we must refer our readers to the work of Mr. Fairbairn. The manufacture of an article so useful, so abundant, so necessary to our happiness, cannot but be interesting.

THE author of this manual has condensed into 48 pages a large amount of information of the highest value to marine engineers. The different kinds of hydrometers, Nicholson's, Sykes's, How's salinometer, are briefly noticed; also that most anomalous instrument of this class at present inflicted upon the engineers in the Royal Navy. The methods of using them, and the results obtained by them, are also stated. There are some excellent practical remarks on the amount and character of saline ingredients, deposits in marine boilers, the boiling temperature of brine, and the capacity for heat and specific heat of brines. A manual upon this subject has been much needed. The recorded experiments upon sea-water brines have not been so extended as to be of practical value to marine engineers. Mr. Swift has entered independently into various experiments and investigations, and has given the results of his labours for the assistance of other inquiring engineering students. Every marine engineer should be thoroughly acquainted with all the facts stated in this manual.

AT the last monthly meeting of the North Shields and Tynemouth Chamber of Commerce, Mr. Mease, Mr. Twizell, and Mr. Shotton were appointed a committee to make the necessary arrangements for the appointment of a competent person to test chains and anchors in the Port of Shields, to enable the Chamber to grant certificates which would guarantee the quality and strength of chains and anchors tested by the authority of the Chamber.

RANSFORD'S SUPPORTS FOR GAS SHADES.

Fig. 1.

A VERY useful gallery for gas glasses has recently been patented by Mr. A. Ransford, of Manchester, in which the following advantages are obtained.

provided, if desired, with catches or other apparatus for keeping it open.

The accompanying engraving shows the cock or tap in section. The induction passage is at a, and the eduction at b. At c, d, are two seats, to which valves e, f, are adapted, fixed upon a spindle g, which passes through the tap, and is provided with a button at h. The valve e is superior in area to the valve f, and the two are therefore held to their seats by the pressure of the fluid, so that, according to the position shown, the tap is closed, in order to allow the liquid to flow into the eduction passage; the spindle g is raised, so as to open ways through the two seatings, c, d. Upon leaving the spindle at liberty, the fluid acting upon both valves will tend to keep them in equilibrium, but as the area of e is greater than that of f, a downward motion will be imparted, and the tap will be closed by self-acting means; and it is evident that the force with which this closing shall take place may be regulated by varying the proportion of one arca to the other.

Instead of the three-armed gallery or support with its central supply pipe and burner, as hitherto used, the inventor makes it in the form of a segment of a circle, with a screwed socket or connection at the outside edge thereof, and a burner socket projecting inwards in a slanting DAVIES AND ALLEN'S APPARATUS FOR position, the connecting socket being tapped to PREVENTING STEAM BOILER EXPLOSIONS. screw on the "gas fitting' or supply pipe, so that when the glass shade is put on the gallery and secured by a thumb-screw, in the usual manner, there will not be any shadow thrown, as

a

Fig. 2.

is the case with the ordinary galleries and supply pipes now in common use. With this arrangement of the gallery and supply pipe free access is left to light the gas.

This invention will be clearly understood by referring to the accompanying engraving, in which fig. 1 represents a gallery suitable for pendants or brackets, and fig. 2 one for pillars or other vertical connections.

a is the part for carrying the glass shade; b, the screw by which the glass shade is secured to the gallery; c, the gas burner; and d, the socket part, which screws on the gas supply pipe.

Fig. 1.

A PATENT for improvements in apparatus for preventing the explosion of steam boilers has just been patented by Messrs. D. Davies and J. Allen, of Manchester, which consists in an apparatus the fire when the pressure of the steam in the applicable to steam boilers for admitting steam to boiler exceeds the desired limit; also for admitting steam to the fire when the level of the water in the boiler descends below the level at which it is considered safe to work; the object being in both cases to damp the fire or extinguish it, thereby preventing the explosion of the boiler.

Fig. 1 is a transverse section of an ordinary

Fig. 2. circular steam boiler, with the apparatus applied; and fig 2 a section through the apparatus on a larger scale; a is the outer shell of the boiler; b, the internal flue; and c, the fire-grate, which are made in the usual manner; d is the case fixed to the outer shell of the boiler, and provided with two

seatings for the compound safety valve e, the upper portion of which is weighted by the lever f, or in any other convenient manner. The sides of the case d are perforated to admit the steam from the boiler to the underside of the safety valve e. the lower part of the case d is attached the upper To end of the pipe g, the lower end is attached to the crown of the internal flue b; this pipe is bent to allow for expansion, and is furnished with fusible plugs at h, placed below the ordinary working level of the water in the boiler.

The action of this apparatus is as follows:When the pressure of steam is sufficiently great to raise the safety valve, the lower valve is also raised, and a portion of steam from the boiler passes down the pipe g, and diffuses itself over the fire, which is thus damped or partially put out; the steam continues to escape through the two valves, until its pressure is sufficiently reduced to allow the valves to return on to their seatings. By this means a considerable saving in fuel and water is effected, and the fireman may rely upon finding the fire in good condition, and the water at its proper level, when he arrives to start the engine in the morning or after meal times. When the level of the water descends below the fusible plugs they will melt by the extra heat, and allow the steam and water to descend through the pipe g to the fire.

The invention may be modified by attaching the scating of the lower valve to the crown of the flue, and connecting the rod of the valve to the weighted lever of the safety valve; in this case the valve rod would have to pass through a stuffing box fixed to the outer casing, or the rod of the valve may be connected to a lever placed within the boiler, and jointed to the spindle of the safety valve.

LIGHTS, BUOYS, AND BEACONS.

No. IV.

We have, in the preceding papers on this subject, glanced at the present condition of the coast illumination of this country, pointed out defects, and suggested improvements. The commissioners, to whose report we have been so much indebted for the information we have conveyed, consider that it is desirable for the efficient management of our lights, buoys, and beacons, that the divided and disjointed management which has hitherto existed should be superseded by some united body. At the present time the government of public lights is directed by bodies differently constituted and situated-namely, the Board of Trade, the Trinity House, the Commissioners of Northern Lights, the Ballast Board, and other local bodies.

"In short," say the commissioners, "the government of lighthouses in the United Kingdom, their management and construction, are all confided to bodies of gentlemen of various employments, none of which necessarily afford them an opportunity of acquiring a knowledge of those branches of science which bear upon lighthouse illumination."

It appears they manage these things better in France, for there the lighthouse service is under the ministry of public works and a special commission, consisting of naval officers, marine engineers, hydrographers, members of scientific bodies, and other gentlemen distinguished for their scientific attainments. The commission have special workshops for testing illuminating apparatus, and they give directions to the manufacturer for every part of the lighthouse fittings, including the calculation of angles for prisms, and curves for lenses, and similar important matters, for which no provision is made in the English system of government. In Spain the system of administration is similar to that of France. In the United States the lights are under one central board, composed of a number of the Government engineers, officers of the army and navy, and civilians of high scientific attainments. In Russia the lights are under the superintendence of the hydrographical department. Holland they are under the management of the Minister for the Marine. While, on the one hand,

In

THE MECHANICS' MAGAZINE.

there is in this country no unity of Government or oneness of control, we find that the men who superintend our lights have no scientific education or peculiar fitness for the work. "The practice in have been to entrust lighthouse illumination to Great Britain," say the commissioners, "scems to persons whose pursuits did not indicate any previous knowledge of the subject; and the fact that for 402 lighthouses, and numerous buoys and beacons, there are at least 174 different authorities, under as many Acts of Parliament, shows the principle of events, not been lost sight of," while "the lightlocal and independent self-government has, at all house boards of foreign countries generally include engineers, hydrographers, and professionally scientific men.'

[AFRIL 26, 1861.

prefer the latter. which have been appointed from time to time since 1822, have recommended The four special committees erecting and maintaining our lighthouses should be "that the expense of defrayed out of the public revenue.' boards-the. Board of Trade, or the Board of Neither are Admiralty-should represent the proposed Central the commissioners decided on which of the two Board in Parliament; but they unmistakeably lean arise a difficulty which may overturn all the calcutowards the Board of Admiralty. But herein may earnest recommendations to the winds. They prolations of the commissioners and send their pose that the Central Board should have money voted by Parliament, without being responsible to arrangement, as it would be contrary to constituthe House of Commons will consent to any such Parliament or any one else. We cannot think that tional practice. We must say we look upon the Central Board with some degree of apprehension, process of amalgamating all the local boards in one pendence and control which have for so many ages characterized British Institutions and the British as it is a departure from that policy of local indegradual encroachment upon local government, and character. And we are aware that there is a may, in the end, prove fatal to the dearly-purchased an extension of the system of centralization, which mended that all the smaller boards be absorbed liberties of Englishmen. But when it is recomsponsible to Parliament for the appropriation of disposal imperial funds, without being directly reinto one, and that that one board should have at its missioners are either calculating without their host, those funds, we must say that we think the comshould prefer seeing the present system or systems or the character of Englishmen is changing. We of lighting our coast perpetuated, with all their shortcomings and inconveniences, than see therefore, to call the attention of Mr. Toulmin Central Board established at such a price. We beg, Smith, who has hitherto shown himself such a faithful guardian of our municipal privileges, to this question.

a

lighting up of our reefs and headlands, and this can We agree with Sir David Brewster, that "the be accomplished only by public boards, composed of great safeguard of human life on our coast is the qualified individuals, and possessing ample resources and extensive jurisdiction." separated from responsibility. and " jurisdiction"

sources

But "remust not be

NEW THEORY ON THE COMPOSITION
OF STEEL.

We have much pleasure in presenting our readers communicated to the Academy of Sciences of a French professor of chemistry, of great repute, with the results of the experiments of M. Fremy, Paris in its sitting of the 11th March last, and arguments. The theory is this:-Steel is not, as adversaries, with further experiments in support 1st of the present month; also the opinions of his of his own, and consequent refutation of their generally admitted, a carburet of iron, but a nitroformed into steel by combining successively with carbide-in other terms, iron becomes transa certain quantity of carbon and nitrogen. According to the author, there does not exist one very celebrated experiment, which consists of single experiment proving practically that steel converting iron into steel by means of the diamond is a combination of carbon and iron. There is a

that is to say, a pure carbon--but this does not action of carbon upon iron were made, other bodies that when the experiments for determining the appear a conclusive fact to M. Fremy. He states than those on which it was intended to try the mutual action were present, and even the experiment with the diamond does not appear to him free from this objection. of the impurities of the melting-pots-the influence of the gases of the furnace penetrating the apparatus, the action of the nitrogen of the air, Without speaking tained in the coal itself, has never been thoroughly or the presence of the different substances contime since made known, that steel dissolved by understood. M. Fremy instances a fact he some acids leaves a residuum entirely different from

pure carbon, but which, by its properties and composition, approaches very nearly certain cyanide productions.

Thus far, both synthetic and analytic experience are far from proving that steel consists only of iron and carbon.

Of the action of nitrogen and carbon upon iron, M. Fremy states that, when iron is submitted to the action of ordinary gas, pig-iron is obtained; but when this gas is made to act on iron previously submitted to the action of nitrogen, it takes the appearance and character of steel; and a very remarkable fact here presents itself-it is, that the properties of the steel depend in a great measure on the quantity of nitrogen given to the iron. If the nitrogenizing has not been continued sufficiently long, the gas, in its action on the iron, produces a substance which is in some measure intermediate between steel and iron; if, on the contrary, the metal has been suitably nitrogenized, the action of the gas produces a steel of excellent grain. When, however, instead of operating separately with nitrogen and carbon, a mixture of the two is made to act on the metal at a red heat, conversion into steel is immediate, according to the relative proportions of the two gases.

Steel, therefore, has been produced by the successive action of two gases upon iron. This theory of M. Fremy has been confirmed in a striking manner by the demonstration of the existence of nitrogen in steel. In submitting to the action of a current of hydrogen gas artificial steels, prepared by him, M. Fremy succeeded in obtaining considerable quantities of nitrogen.

It then became interesting to submit to the same proofs steels known in commerce, for the purpose of discovering nitrogen in their composition. With this end in view the author operated on three different, but much esteemed, varietiesthe French steel of Jackson, the English of Huntsman, and the German of Krupp; these having been reduced to filings, and freed from all foreign matter, were submitted, at a red heat, to the action of dry hydrogen gas. In these trials the filings disengaged, during the whole time of the experiment, large quantities of ammonia. This last experiment seems to leave no doubt that nitrogen forms a constituent part of steel. Steel, concludes M. Fremy, is not a simple carburet of iron, but a nitro-carbide. It seems to me, adds the author, that these researches ought to exert a considerable influence on the metallurgical operations that bear on the manufacture of steel.

We now come to the sitting of the 1st April, in which several communications were presented by their authors antagonistic to the theory of M. Fremy, and especially notice those of M. E. Jullien and Captain Caron. In 1852, M. E. Jullien, an engineer of great ability, and known as the author of one of the best works published in France on the steam engine, presented to the Academy several articles on the composition of steel. He is a partizan of the old theory, that steel is a simple carburet of iron; but he views it in an entirely new light, and gives it an eminently scientific bearing. He says steel does not consist of a pure and simple combination of carbon and iron, but is a dissolving of the carbon in the metal.

Under the title of New Theory of Cementation, Captain Caron read a paper, in which he directly combats the views of M. Fremy. Captain Caron does not admit the presence of nitrogen in steels. He seems to have taken for the text of his works the conclusions of a German chemist, M. Mar. chand, who terminates an article, inserted in the Journal für Pratische Chemie, in 1860-" If there is nitrogen in steel, it belongs necessarily to the substances mixed with the iron, which no more form an integral part of the metal than the scoria one finds mixed with it." So decided an assertion will appear difficult to sustain in presence of the experiment of M. Fremy, which obliges every variety of steel to disengage ammonia when treated with a current of hydrogen gas. Is not this sufficient evidence to prove the presence of nitrogen in steel? Indeed, one is much surprised to find Captain Caron contest the existence of

DAVIES'S IMPROVEMENTS FOR CASEHARDENING AND SOFTENING IRON. MR. G. DAVIES, of Serle-street, has recently patented" improvements in the processes of cementation or case-hardening and softening iron."

nitrogen in this metallic product, when it is known the particular process he himself extols for the production of steel consists in the use of cyanides, and even of the cyan-hydrate of ammonia, substances peculiarly nitrogenic. He states that carbonic hydrogen makes better steel than the cyanides; but has he not produced white This invention has for its objects, firstly, the iron, and not steel, by this process? and even if cementation or conversion into steel of wrought he did produce a little steel, was it not because iron of all kinds by means of gases proceeding from the iron contained a small quantity of nitrogen ? different matters hereinafter named; secondly, the To Mr. Caron's observations M. Fremy has cementation of cast iron either moulded or othergiven the best of all posssible answers by new ex-wise; thirdly, the cementation or case-hardening periments, which, in themselves, reply to the to any depth required, and at any part of either objections against his ideas, or throw new wrought or cast iron; fourthly, the softening of light on the other portions of this question. the most brittle kinds of iron, so as to give it M. Fremy has already proved that steel almost the malleability of lead; and, fifthly (by steel cannot be made without nitrogen; and that a combination of the above processes), the fabriall manufacturers made nitro-carbide of iron cation of cylinders, drums, or other articles, without being aware of the fact; he has even which require at the same time great strength, proved that the degree of steel is proportioned hardness, and malleability. to the quantity of nitrogen given to the iron. In the sitting above mentioned, M. Fremy read to the Academy (which was almost entirely occupied with the discussion of this fundamental question) a paper, in which he proved that steel is destroyed by being deprived of its nitrogen. He produced to the members of the Academy a blade of cast steel, of which one portion only had been submitted to the action of a current of hydrogen gas, the metal being kept at a red heat. The operation lasted for three hours, and during all this time the steel disengaged constantly ammoniacal vapours, and probably other nitrogenic alkalies, whose vapours possessed the smell of burnt horns; the part of the blade which had been submitted to the influence of the hydrogen, and which had lost its nitrogen, became transformed into iron, endowed with a wonderful malleability, exceedingly soft and not to be changed by tempering, whilst the part of the blade which had not been de-nitrogenized preserved all the characters of steel.

Against the theory of the presence of nitrogen in steel has been raised this very serious objection that the greater portion of all the steel used in the arts and manufactures is converted by a process which seems to exclude all possible intervention of any substance of which nitrogen is a component part. The conversion of some steel takes place in cementing ovens, where the process is confined to heating of bars of iron placed in the midst of a mass of pulverized charcoal. M. Fremy has taken every care to answer this objection. According to him, and as already advanced by Saunderson, the air continually circulates through these cementing ovens, and the nitrogen of the atmosphere is absorbed by the metal during its passage through the mass of fuel. M. Fremy, however, produces more conclusive evidence, by establishing the fact that charcoal, produced from organic matter, as that used for the cementing ovens, always retains its nitrogen. He submitted to a current of hydrogen gas charcoal produced from organic matter nitrogenized, and whilst under the influence of hydrogen this substance, for a long time, disengaged ammonia. This experiment proves that organic substances nitrogenized, as those which constitute the animal or even vegetable tissues, leave by calcination a nitrogenized charcoal, which afterwards, by slow combustion, similar to that which takes place in cementing ovens, disengage their nitrogen in the shape of ammonia, under the influence of hydrogen gas or the vapour of water.

Thus, according to M. Fremy, the nitrogen, useful in the manufacture of steel, would be furnished from the air, and from the charcoal itself which is always nitrogenized.

The iron for conversion into steel by this process should, says the author, be as pure as possible and free from phosphorus, sulphur, and silica; for nitrogen will not exercise its steeling properties on iron containing either phosphorus or sulphur.

We shall, no doubt, have occasion to recur to this subject, for there is scarcely a more important question in any branch of our manufactures.

|

The processes are as follows:-For wrought iron a mixture is to be formed of equal parts of any vegetable and animal matters, either solid, liquid, or gaseous. This mixture is enclosed in a gas retort in a proportion of from 8 to 20 per cent. the weight of the iron to be converted, and according to the quality of the latter, which is also placed in another vessel or chamber (also closed) in immediate communication with the gas retort, and at the same time with a gasometer, in order to cause an equal and regular pressure of the gas contained in the apparatus. The gas retort and the vessel containing the iron are placed over two furnaces, and the latter is to be heated to nearly a cherry redness, and the former to a less elevated degree. The gas thus produced penetrates the pores of the metal expanded by the heat, and cementation takes place with a rapidity hitherto unknown, and steel is produced very superior in quality to that made from the same iron even by the ordinary process.

For cast iron a mixture is to be formed composed of about 90 per cent. of calcareous matter, either mineral or animal, especially common lime, lime obtained from the calcined bones of animals, or oyster shells, or even iron ore. To either of these ingredients, previously triturated, is to be added about 10 per cent. of the mixture already mentioned for the cementation of wrought iron. The pieces of cast iron are then placed in alternate layers with this mixture in a closed crucible, and in a few hours, according to the thickness, the cast iron (whether moulded or not) is converted into fine hard steel, without the least alteration in form or otherwise.

For partial cementation of wrought iron articles, the part which it is desired to remain intact is to be covered with mineral or animal calcareous matter, and the cementation penetrates regularly over all the rest of the piece, which is in contact with the gas or cementing mixture. For the partial cementation of cast iron articles this process must be reversed; that is to say, the parts required to remain intact must be covered with the cementing mixture for wrought iron, and the part to be converted must be covered with the mixture above described for cast iron.

For softening brittle iron the mixture abovenamed for cast iron, namely, calcareous matters or iron ore, is to be used. By these means, in a very few hours, the most brittle iron is made so pliable and malleable, that it may be bent and straightened again cold without the least cracking, and is easily filed. In this manner, and according to the principles of this invention, iron of very inferior quality can be softened so as to be easily worked, and when finished, as desired, may be brought again to any required degree of hardness.

For the cementation of wrought or cast iron, especially for railway purposes, the furnaces are composed of hermetically-closed chambers or crucibles, the sides of which are vertical, and formed of cast or sheet iron, covered on the exterior with a coating of fire-clay, to prevent the too great action of the fire thereon. The bottom and cover of each crucible is made of fire-clay, so formed as to make a close joint, and to be capable

driven by bevil gearing from the engine in the COLONEL O'HALLORAN'S KNAPSACK usual way.

FOR VOLUNTEERS.

A, A, in the above engravings, is the spindle of the governor which is made hollow; B, a rod fitting loosely into the spindle A; C, a casting securely fixed on the spindle A; this casting is formed with a stuffing box at D, through the packing of which the rod works steam-tight; E are two ordinary governor balls or spheres of metal, respectively fixed upon the pendulum rods G, G, the upper ends whereof are formed bent or cranked; the rods G, G, are connected to casting C by pins, and said casting is formed with recesses to receive the rods G, G, and keep them steady when in action; H is a square piece of metal, which has a hole formed through it sufficiently large for the screwed part of the rod B to pass freely through the piece of metal H, and parts affixed thereto slide in the opening X of the piece C, and the piece H has recesses formed therein to receive the short bent ends of the rods G, G, which operate thereon as hereafter stated; I is a screwed collar of brass fitting upon the screwed part of the rod B, the lower part of the collar I is formed enlarged, and with a shoulder as exhibited for connecting the collar between the piece H and a strap K fixed on to the piece H, so that as the collar is moved round from right to left or vice versa, which may be effected by a lever wheel L fixed on to it, the effect will be to ensure the lifting or lowering of the rod B, as the case may be, and also the valve M. The construction of these valves or compound valve, and mode of connecting same to the rod B and with the valve box are as follows:-M is a double cup valve of gun metal or other suitable metal, the stem N whereof fits loosely around the spindle A; O is a key or cotter fitting tightly in lots formed in the rod B and stem N, a slot is also formed in the spindle A of sufficient length and size for the key or cotter O to pass freely through and along as the rod B is raised and lowered; the edges of the cupped parts at X, X, of the double cup valve M have inclined notches formed thereon, Mr. Berrington has devised straps terminating and there are similar curved notches formed on the in rigid ends b, a, of malleable steel, each about edge of the valve seats P, P, the cupped parts of 10 inches in length, which clasp the chest in the valve M have their outer surfaces formed cylin- front in a downward direction, not transversely, drical, and the seats of such said valve are similarly and are kept in place by a small central strap formed and fitted so as to move easily therein, the, which extends a few inches across the chest, said valve seats are fixed in openings formed in the valve box.

WE are requested to remind intending exhibitors, in the industrial department of the Exhibition of 1862, that Her Majesty's Commissioners have named the 1st of May next as the date before which all applications for space must be sent in. By far the larger portion of the space which can be allotted to Eritish exhibitors has already been applied for.

but which it is important to observe has no contact with the chest whatever; this contingency being guarded against by the application of two leather blocks, one under each end of the strap, which elevate it fully half an inch above the body. The intervening media b, c, d, which connect these ends with the knapsack at its points of suspension d, d, immediately below the transverse slab of wood i, are of leather only; and as the connecting points, before and behind b, d, are

| purposely so adjusted, as to fall below the level of the top of the shoulders c, c, on which the slings or intervening media rest, the entire weight of the knapsack and its contents are brought to bear on the top of the shoulders also.

The rigid ends which are of highly-tempered steel, covered with leather, are capable of adaptation to the form of the wearer, be he round or flat-chested, by the simple action of bending or straightening them with the hands. They are regulated to the proper length by means of the two buckles at the top, on which the canteen rests, and aided by the straps which hook on to them diagonally from the lower extremity of the knapsack, one at each side, maintain the knapsack in its place, the shifting or rotatory power on the top of the shoulder being very small, and by Colonel Spiller's contrivance obviated altogether, for, as the steel arms f, f, and band e, project towards and rest against the body, they necessarily preserve the knapsack in a forward position, close to the centre of gravity of the man, and render it impossible for any derangement of equilibrium to take place; they further give ventilation where it is so much needed; and, as they work on knuckle joints, can be accommodated like the limbs of a pair of compasses to the breadth of loin of the wearer, or folded flat when not in use, by undoing the corner straps and buckles g, g, which retain them in place when fitted. presents a light and flexible band of ash, sewn into the lining of the knapsack, and giving to that portion of the interior surface which presses against the shoulder-blades, concavity of form, increasing thereby ease of carriage and freedom of motion. There is a separate and commodious flap pocket for the great coat, which keeps it perfectly dry, and makes it readily available when wanted, without disturbing anything else. The knapsack can be had of any colour to suit the clothing and accoutrements of Volunteer Corps-either rifle grey, or War Office grey, or black, with black or brown leather straps, to order. The dimensions are 134 inches in length, 12 in breadth, and 3 in depth. minimum requirements for field service, as laid Weight, with down by the Inspector-General of Volunteers, 123lbs-with full kit, 15lbs. The cost of the knapsack and straps, 20s.; canteen with cover and strap, 2s. The cost of the great coat with detached hood and cape, waterproof, 30s. to 40s., according to quality.

e re

Messrs. Charles Prater and Co., army coning-cross, S. W., London, have both patents tractors and accoutrement makers, No. 2, Charvested in them (the Berrington and the Spiller), and are the sole manufacturers.