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correct, and that all cylinders would follow cast solid burst at the twentieth round, the the bars in that manner, which is the only part “ this law."

other stood 249 rounds. When examined after- of his process which has any pretensions to In the case of iron tubes, an experiment wards, the gun cast hollow was found to be, in novelty. The kind of iron you describe is one which any one can make is decisive as to the one part, fissured, the outside and inside having of the modifications of cold short iron, and is stretching. A leaden ring fitted on such a tube solidified before the middle. It is probable known here by the emphatical name of rottenwill stretch with it when strained, but will re- that even where no absolute fissure was found, tough. I have long known that almost any main enlarged when the iron is permitted to the portion of metal intermediate between the cold short iron may be brought to that state by regain its original size. Mr. Greener, of Bir- two cooling surfaces was less dense than it rolling it very hot, or by drawing it across the mingham, made a series of experiments with the should have been.

anvil so as to spin the crystals into threuds ; barrel of a fowling-piece, having leaden rings at Captain Blakely does ample justice to Mr. and, by certain mechanical processes, good iron intervals on it, for the purpose of showing how Rodman's invention, but deems his own plan may be rendered cold short. Nevertheless in much each part was enlarged during the dis- the better. “One advantage my plan certainly neither of these cases is the quality of the iron charge of the piece. Where he found this en-"has,” he says: “I can use, to obtain the altered ; the good iron continues strong, and largement less than at other parts he concluded greater part of the resistance required, a metal the cold short is very weak. I look on Mr. that the barrel was stronger than necessary, and "much stronger than cast iron, while retaining Cort's iron as a cold short, whose crystals are modelled the next he made accordingly. The “that metal for the interior of the tube, for spun out by the rolling, and which is mixed with enlargement of tubes when pressed on from “which part it is so suited ; thus securing the a large quantity of half metallised earth. It is within, being thus proved beyond the possibility “hardness and inflexibility of cast-iron, and the tender to the file, and soft to the hammer, rusts of doubt, the simultaneous diminution in the tensile force of the toughest steel. Wire even, very readily, and ought never to be used where thickness of their sides will be readily admitted. “the strongest form of iron or steel, can be used it is subjected to any strain, as it is very weak, “No person could expect a ring which fitted a with great advantage in some cases. The therefore unfit for engine work, ship work, &c., " little finger to be enlarged to fit a first finger saving in size of guns, therefore, in expense of but good for nails, because easily wrought : but “ without becoming thinner," as Capt. Blakely transport would be enormous. This is, how- then the nailors complain that it wastes more says ; and as any thick cylinder or tube may be ever, a very small matter, in my opinion, com- than the common cold short, I suppose because considered as composed of several concentric pared to the advantage of, by this means, not so well freed from its cinder. I speak only smaller ones, it is evident that each of these, by " being enabled to make cannon of a size and of the iron made from cold short by this probecoming thinner when stretched, loses some strength hitherto impossible, and still impos- cess,

Good iron is hard under the hammer and of its power of pressing the one above it. Here “sible by any means which do not ensure that stubborn to the chisel and file, breaks white, we have the whole of the very important theory" each part shall do its work. Nothing would generally granulated, but the very best is fibrous, of this able officer.

“ be so conducive to peace as arming the vul- and white like silver. I find I am getting into The method of constructing cannon which he "nerable parts of every coast with guns so

a dissertation on iron which I must shorten. advocates in accordance with it is, then, simply powerful that one or two shells from them Mr. Cort has, as you observe, been most illibeto form such parts of them as require great “could destroy a ship. Few have any idea rally treated by the trade ; they are ignorant strength of concentric tubes, each slightly too how inadequate to the end desired are the brutes : but he exposed himself to it by expossmall to go over the one below it without force; means often employed.”

ing his process to them before it was perfect; the amount of this difference in size being so re- On another page we give a most interesting and they saw his ignorance of the common gulated that with a certain amount of pressure account of Captain Blakely's development of operations of making iron, laughed at and decach tube shall be equally strained, or that the his invention, in his own language.

spised him; yet they will contrive by some outside (which can be replaced if broken) shall

dirty evasion to use his process, or such parts be most strained. One of these tubes should

THE CASE OF HENRY CORT,

as they like, without acknowledging him in it. extend the entire length of the gun, the others

I shall be glad to be able to be of any use to may be formed of more convenient sizes. We HIS INVENTIONS IN THE MANUFACTURE really should like to see this system put into

OF BRITISH IRON.

The iron referred to in this letter, both from general practice. Its value can scarcely be

the terms employed and from the period of the over-estimated.

THOMAS WEBSTER, M.A., F.R.S., &c., Barrister-at-Law. trials seen by Watt, must have been ordinary Captain Blakely honestly informs us that

bar iron subjected to the treatment described from the “ Reports of Experiments on Metals The puddling process as described in the speci- in the specification of the first patent. The “ for Cannon," he learns he is not the first per: the working of the iron by the grooved rollers

, cess is conclusive on this point. The sympathy

fication of Cort's second patent, with or without omission of all reference to the puddling prostraining of the parts of a gun. In 1851 Lieu was an improvement in the manufacture of bar of Watt, then struggling with the opposition tenant Rodman of the United States Ordnance from cast iron; the piling, faggoting, and and difficulty of introducing the inventions the proposed, for that purpose, to cast guns hollow heating of the iron in a hot-air furnace in- subject of his patent dated 5th January, 1769, and cool them from within. On the 30th July stead of a hollow fire under blast, and the work- and involved in litigation with those who of that year, at his suggestion an eight-inch gun ing and welding of bar iron by the grooved sought to evade the moderate payment of a was cast hollow by means of a core formed on a rollers was an improvement in the application small portion of the saving which the immortal tube of cast-iron. Through this a stream of of bar iron, however made, to the purposes for genius of the inventor had conferred upon them, water was kept circulating until the gun was which that material was required. Îhe uses must furnish an excuse for the severity of the cool. By this means, Mr. Rodman made the from iron made by the ordinary process, when language of a portion of that letter, and of the inside solidify first. The next layer solidified, piled, faggoted, and worked as described, were strictures upon persons who have shown no indisof course, at a greater temperature than that of much better than had ever before been made position as a body to give due credit to Cort, the extreme inside at that moment, as this had of British iron ; but such uses made of puddled though the sequel will show how much there is already had a short time to cool and contract. iron, worked, piled, faggoted and rolled ac- to justify the most severe censure on the indifHad the outside of the gun been kept liquid cording to the complete invention, were equal ference with which the nation has treated the until all the rest had gradually become solid, to those theretofore made of foreign iron only; family of one of its greatest benefactors. This giving out all heat through the core only, doubt thus the home was placed upon an equality letter is important as showing the attention

which Cort's discoveries had then received from less the gun would have been in a condition with the foreign manufacture. very nearly approaching that required by theory,

Cort would appear to have freely invited the two of the most eminent men of the time. so far as the initial tension on the external por manufacturers of iron, of scientific persons, and

The invention of Cort, as disclosed by the tions is concerned. As it was, the gun was of others interested in the subject at a very specifications of his two patents, taken out much stronger than another cast solid at the early stage of his discoveries. The following within thirteen months of each other, is pudsame time, of the same size, and of the same extract from a letter from the celebrated Watt Aling, piling, and faggoting, and heating in an metal. The latter burst after 73 rounds with to the equally celebrated Dr. Black, will be air furnace, and working by grooved rollers ; 10 pounds of powder and one 64-pound shot ; read with much interest. It bears date the 6th the air or reverberatory furnace was furnished that cast hollow was fired 1,500 times with the of June, 1784, that is, just after the specifica- with a hollow bottom, suitable for receiving the same charge and is still sound. On the 21st tion of the first, and before the specification of fluid mass and permitting it to be worked. This August, 1851, two ten-inch guns were cast at the second patent :

furnace was employed instead of the ordinary New York from the same metal, one solid and

“ Birmingham, June 6th, 1781.

finery furnace theretofore used. Much has one hollow. The latter was cooled from within “Previous to your letter I had heard much of case respecting the construction of the furnace,

been said in the course of the controversy in this like the eight-inch gun, but the outside was Mr. Cort's process for making bars, and have the substitution of iron or cinder for sand also allowed to cool, though more slowly. These seen a great deal of his iron; though I cannot guns were proved by repeated firing with 18 lbs. perfectly agree with you as to its goodness, yet the work entitled Mechanical Inventions by James Watts

• See “Extracts from Mr. Watt's Correspondence," in of gunpowder and one 124 lb. shot. The gun, there is much ingenuity in the idea of forming I by Muirhead," Vol. 11., p. 189.

him."*

BY

No, VI.

bottoms in the puddling furnace, these and his own. I can only add, I am happy to be iron into a malleable and tough state by the other subsequent improvements contributing to called upon to pay this small tribute to your above process, equal to the best Orground iron, the certainty, perfection, and cheapness of the father's memory, to whom I consider this king- which we flatter ourselves will be clearly invesresult are additions to, and in no respect de- dom, the world at large, and the iron trade in tigated by the following experiments :tractions from the merit of Cort, who was the particular, greatly indebted.

“By putting a piece of the best Orground first to place the British in a position to com- “ (Signed)

ALEXANDER Raby."

iron, marked (L), of nine pounds weight into pete with the foreign manufacturer.

The letter of Watt to Dr. Black is the earliest The partner and associate with Cort in the the air furnace, and when so hot as above deaccount that has been preserved of a cotemporary business at Fontley, Adam Jellicoe, was, as scribed took out and passed between the rollers, on the subject of Cort's inventions. The follow- appears by an agreement dated the 8th of Jan., whose pressure is such as to discharge the ing letter from Alexander Raby, who had been 1781, entitled to one-half the premises, &c., on greatest part of the dross and impurities from in the iron trade between forty' and fifty years, paying half the cost and one-half of all contracts the said iron ; for on weighing it after it had and well acquainted with its manufacture at and stock-in-trade, at a price to be settled by passed through the above process we found it least twenty years prior to Cort's inventions, arbitration, and in consideration of finding the weighed only 8{ lbs., so that it discharged of will be read with interest; though not written necessary capital was to participate equally in a pound in nine.

“We also tried three other pieces of iron of for many years afterwards. It was addressed the profits of the trade. It appears that Cort to Mr. Coningsby Cort on the occasion of the advanced £20,000, and Jellicoe £27,500 on the the different weights and qualities by the above inquiry by the Parliamentary Committee, in Fontley business. In one respect Cort was process, whith are as follows, viz., a piece of the 1812, into the inerits of Cort's inventions :- more fortunate than many of his class ; the 2nd sort of iron of 9 lbs., which on weighing “Llanelly, June 20, 1812.

practical instinct and indomitable perseverance, after it had passed the above process weighed

the characteristics of his inventive genius, were only 64 lbs., so that it discharged 24 lbs. ; a "Dear Sir, -I have received your letter of not smothered by the want of pecuniary means piece of the 3rd sort of 5} lbs. weighed after the 15th past. What I said to Mr. Giddy and to demonstrate the truth of his speculations. passing the above process, only 3 lbs.; a piece Mr. Maddox upon your father's mode of making The manufacture by his process from the com- of very bad iron of 4} ]bs. weighed after passing bar iron, I have not the least objection to state monest description of cast iron of iron equal the above process only 23 lbs. ; by which it in writing.

and superior to the best qualities of foreign iron appears that the dross discharged by this pro“I was in the habit of intimacy with your became an established and admitted fact. Im-cess is in proportion to the goodness of the father several years before he began his puddling mediately after the date of his second patent, several sorts of iron ; and by every trial we system for making bar iron, and when he began Cort was able to obtain the ear and command made, as far as we could discover by the difit, and after he had used it some time, I was the attention of the public departments to his ferent discharges of the dross and impurities still of the unbelieving tribe, that thought it invention, which in 1785 and 1786 was made from the different sorts of iron, it all became would never come to anything. I expressed the subject of trials in the dockyards of Ports- equally pure to any iron that can be manufacmyself so both publicly and privately at that mouth, Deptford, Woolwich, Sheerness, Chat- tured. We also had some faggots of old iron time, and I may venture to say most other ham, and Plymouth. The result of these trials hoops, and of the smallest sort of Birstrel iron people in the iron trade thought of it as I did,

was published in 1787, accompanied by a put into the air-furnace and worked under a and I am sure no man thought well enough of statement of facts authenticated by the autho- forge-hammer of 7 or 8 cwt., which welded it so it for a long time after to claim the merit of rity of Lord Sheffield, Dr. Joseph Black, and entirely as to make it perfectly one solid body, the invention, nor was it thought of otherwise David Hartley.

and at the same time also discharged the greattill your father, by his perseverance, had so far furthered the plan by producing most expedi- ments which have been preserved, and from the passing it afterwards between the

rollers and The following extracts from original docu- est part of the dross, which we proved by tiously large quantities of bar iron by working printed

statement so authenticated, will be read Slitting into hoops, and another piece into bars it in grooved rollers after being puddled, inwith interest :

of a half-inch square, and then drawing into stead of under hammers, which invention of

“Navy Office, 13th June, 1783.

bolt staves, which was very good. We also rolling bars was also entirely new and his own. Attempts had been made to roll round iron in “Messrs. CoRT AND JELLICOE - In return to made a tackle-hook from some of the same iron, hollows turned in rollers, but never to roll bar your letter of yesterday requesting that direc- and put it cold under the forge-hammer, which iron in grooved roll, which is very different, as

tions may be given to inspect the nature of did not break it. We are therefore humbly of round iron is not rolled in grooves, but in loose your new-invented method of working iron, made both from old and Birstrel iron, &c., when semicircles. No man, I think, will attempt to acquaint you that we have directed some of say he was the inventor of rolling bar iron in Portsmouth officers with the master-smith to properly manufactured, as set forth on the other grooves, or to prove your father was not. proceed to the works and report fully their side, by being heated to a proper heat in the

air-furnace and worked under the rollers or “Unbelieving as I was, I soon became a con- opinion.

(Signed) vert to his mode of puddling and rolling bar

“ CHAS. MIDDLETON,

forge-hammers as therein described, is very iron both as to quantity and quality. Some im

“J. WILLIAMS,

proper iron for making mooring-chains, bolt“Geo. ROGERS."

staves, tackle-hooks, &c., &c., &c., or any other provements soon also took place by first refining

uses it may be wanted, for this or any of His the pigs or cast iron before they puddled it, but

" Portsmouth Dock, 7th July, 1783.

Majesty's yards. it was obliged to be puddled before it was made "HONOURABLE SIRS,-In obedience to your “We had also two links of large mooringinto bars ; nor could their refined metal be directions of the 13th post, in consequence of a chains drawn from the air furnace, under the worked to profit or with expedition by any letter from Messrs. Cort and Jellicoe, request- forge-hammer, which we found to be quite solid other mode than by puddling. I will venture ing directions may be given to inspect the nature and much tougher than those made from the to say that owing to that system and the use of of their new-invented method of preparing, common forge; and herewith we return Messrs. grooved rolls, this kingdom is indebted for its welding, and working various sorts of iron, that Cort and Jellicoe's letter, which being subpresent proud state of the iron trade, when in the master-shipwright and his first assistant, mitted, stead of being obliged to bow down to the with the storekeeper and master-smith, should “We remain, Honourable Sirs, north of Europe for a scanty supply of that use- proceed to the works and thoroughly examine

“Your most obedient Servants, ful article at a very high price, we are enabled the process they make use of, and report fully to supply all our own wants with an immense their opinion thereon, returning the enclosed

“(Signed) Geo. WHITE,

WM. RULE, annual saving to the country. But was not with their answer.

“J. BADCOCK, J. GREENWAY." only all Europe, but all the world to depend “ In answer, pray leave to acquaint you upon us for bar iron, Great Britain would be that we have been to Messrs. Cort and Jellicoe's about the same time in reference to the trials

,

Other letters and communications passed able to supply the whole, both good and cheap: mills at Fontley, and thoroughly examined the which established conclusively to the satisfaction And to whom is all this grand improvement and process they make use of in preparing, welding, of the authorities the superiority of the iron national benefit owing ? and with whom did it and working various sorts of iron, which they made according to Cort's processes of manuoriginate but with your father ? Envious per- do by putting the iron designed to be worked

facture. sons may want to pervert the merit that is due into an air furnace, where remains until it is to him, but when I recollect the trouble, pains, so hot as to be between a welding and a fluid

LIST OF NEW BOOKS. and expense he was at to make converts, so as state, when it is either worked under a forgeto increase the quantity made by his mode hammer of 7 or 8 cwt. or passed between two Busk’s the Rifle and How to Use it, 4th edition, 2s. 6d. when he was himself convinced of its utility, rollers of about 9 cwt. each, which immediately Cassell's Natural History: the Monkey Tribe, 25. and the premium some great men then in the and very visibly destroys the greatest part of Fairholt's Tobacco, its History and Associations, 9s. iron trade were in consequence thereof willing the dross and impurities from the said iron, and Our Farm of Four Acres, 4th edition, 28. to pay for the use of his patent, surely that if required will also weld two bars together at Routledge's Natural Ilistory, by Wood, div. 1, 45. alone is sufficient to prove the inventions were the same time, as well as bring the most brittle Russell's Rifle Clubs and volunteer Corps, 18. od.

No. VII.

[JULY 22, 1859. THE GLOBE TELEGRAPH.

less extent the available electricity of the plates. case, which is quite straight, and allows the letters

The importance of this consideration becomes to project equally throughout, in the machine, and In a late number a review was given of Mr. obvious when we take into account the enormous lays the medal in the space alluded to: He now Beardmore's pamphlet upon “The Globe Tele. graph,” under which title was proposed a system circuits, where the imperfectly insulating covering the latter catches the edge of the medal. Conloss of power which must occur in submarine puts his hand to the wheel, and turns it until the

sliding bar advances with its wooden cheek, and of electro-telegraphic communication, which bids fair to solve the difficulties which attend the of the wire is exposed to the constant action of tinuing now, per wheel,

the forward pressure, the high-tension electricity.

medal is made to revolve in front of the steel transmission of signals in long submarine wires.

letters, and to take from them the requisite in. To most of our professional readers these difficul

In April of the present year a trial of the new

scription. After passing beyond the case of the type ties, and the method by which it is now shown system was made between Guernsey and South. the medal is necessarily released, and if on examthey may, in all probability, be overcoine, are ampton, in which, with single plates of zinc and ination found free from error or imperfection, is already familiar ; but we think it necessary, in copper, 110 miles apart, and less than three square placed in a numbered envelope, and for the present

set aside. Mr. Compositor now looks to the next order that the general reader may be au courant feet in size, sufficient electro-motive force was

name on his list, re-sets the type in accordance with a subject involving. perhaps, the very possi- obtained to work a Siemens instrument. Little

therewith, and repeats the operation as described, bility of successfully establishing a telegraphic attention appears to have been directed to this and to be continued until the list is completed; link between the Old World and the New, to give experiment, which we would now offer for the but it is unavoidably a slow process

.

The Mint may at this stage be said to wash its a brief apergu of this plan, and of the advantages consideration of those who were present at the said to be derived from it.

reading of Mr. Varley's paper at the Society of hands of medals, for they are despatched after The galvanic arrangement employed by the Arts in March last, under the impression that it and thence to the court jewellers, Messrs. Hunt patentees of the “Globe Telegraph” consists might throw some new light upon the difficulties and Roskell, to be further fitted with clips,

ribands, and clasps, one of the latter, indeed, simply of the "two dissimilar metals” with of submarine telegraphy.

being given for each important action in which which Subzar experimented, and the effect of

its recipient may have been engaged. The which in contact was (some fifty years afterwards),

MONEY-MAKING AT THE ROYAL MINT.

jewellers return them to the Government office, investigated by Galvani, and made the subject of

to which they pertain, and soon they are seen a science by Volta. The battery arrangement In order to make our explanation of the mode of decorating the breasts of those who have nobly discovered by the latter philosopher in his Cou- must be stated that there are two machines em- for the Kaffir, the Russian, the Persian, and the

getting up medals yet more clear and explicit it earned them. Besides the general medals given ranne de Tasses, consisting of a series of alterna- ployed at the Mint for lettering, after they are Indian wars, there are occasionally struck and tions of dissimilar metals contained in separate struck, the edges of those badges of honourable distributed particular decorations for“ meritorious vessels, and connected one with the other by a

distinction. These machines are so constructed service," "distinguished conduct in the field," metallic wire, is relinquished for a single couple, rank, name, and ship, or regiment of each person medals in all cases are of the same intrinsic value,

as to indent, by the aid of small steel type, the and for “long service and good conduct.” The the amount of surface of which is regulated destined to receive a medal, upon its edges. As weight, and material, namely, 5s, 6d., one ounce, according to the distance between the metals; may be imagined, this operation is a tedious one, and of fine silver. The mountings, labour, &c., and the wire, by means of which a metallic con- and when many have to be lettered in a com- make them cost the State, however, about eight nection is established between, then becomes the paratively short space of time, a compositor from shillings each. medium through which the current is rendered an ordinary printing office is engaged on the Thus much on medals; now let us revert to a available.

duty. In the case of the Crimean medals--of process intimately connected with money and

which we believe, so indiscriminately were they medal making—that of the conversion of square By increasing the number of the galvanic bestowed upon English, French, Sardinian, and bars of cast steel into dies. Without these no couples, and by immersing them in an active Turkish soldiers and others, 400,000 were dis- legitimate coining can go on, whatever the ladle chemical agent, Volta was enabled to obtain the tributed—it was found impossible to letter more and mould, in an illegitimate sense, may accomenergetic action due to what is termed “tension”

than a select few. It would have been ex- plish “down Whitechapel way.” All the dies electricity. By “ tension,” in opposition to ceedingly difficult to collect the names of the used in the Royal Mint are made in that establish

motley host which comprised the allied forces, ment, and it would be improper to conclude our “quantity,” is understood that property by which and more difficult, perhaps, to decipher those series of papers on money-making without allusion an electric current produces in a higher degree names, or find space for them with the other par- to the manner in which they are manufactured. the effects of muscular disturbance in animal ticulars, and the clips, upon the limited circum. The bars of steel intended for conversion into bodies, and of electro-chemical decomposition in ference of the medal. Officers and men, however, coining dies, are selected from the very finest inorganic compounds. But it is by no means

of the British Naval and Military Services had the that can be produced. The Messrs. Turton, of

privilege allowed them of returning, through Sheffield, have obtained honourable mention for necessary that this property should exist in any the Admiralty or the War Office, their medals to the rare quality of the article for the especial purhigh degree for the production of those pheno- the Mint for the purpose of having their names, pose which they have supplied. A much larger mena on which depends the transmission of elec. &c., impressed upon them, and many, we believe, per-centage of coins are obtained, we are credibly tric signals, and, on the other hand, it is now availed themselves of the opportunity.

informed, from dies made of their steel, than evident thłat the employment of high tension and worked by hand. In one the medals may that we were about to carry out the decimal sys

The machines for effecting the object are small, from those got up from any other. Supposing electricity is productive of serious disadvantages be lettered after the clips have been attached, and tem of coinage as shadowed forth lately in our as regards "induced currents” and the loss of in the other before. In the first the medal is put own columns, and that the engraver of the Royal electricity. The usual electric signal consists in into the machine vertically, and the type is made Mint had received instructions to prepare designs the deflection of a magnetic needle ; and this de- to travel underneath it; in the second, which is and get up dies for the one or two new coins flection may be produced with a current of very fore more fully describe, the medal is placed hori- commence bis important duty much after the

that usually employed, and which we shall there which would thus become necessary, he would low tension by means of a short coil of a thick zontally in the machine, and made to revolve following fashion :wire, upon which the ordinary telegraphic current against the type. This machine consists of a firm With pencil, paper, and compasses, he would take would produce a scarcely perceptible effect. This oaken bed, supported on four legs, and fitted with a the initiatory step, that of sketching the obverse being the case, the employment of tension elec. hand-wheel and crank, calculated to give to a and reverse of the coin—say the cent, for extricity, with long coils of five wire, offering a con- square horizontal bar of iron working in a planed ample. Having satisfied himself upon the prosiderable resistance to the circuit, certainly ap. this iron bar, which rises to perhaps of an inch pieces, the engraver would next obtain a piece of

groove a travel of some six inches. Parallel with portions, devices, and inscription of the embryo pears anomalous; and the substitution of the above the groove, and to one side of which is at steel cut from a square bar, of the best quality, contrary conditions would be a step in advance in tached a boxwood cheek-parallel with this is a forged into the cylindrical forms of the proper the art of electro-telegraphy.

stationary recess for holding the type case. Be- dimensions, faced in the lathe, and in a soft state. But the current produced by the simple tween the cheek and the type case there is a space To the faced ends of this he would transfer with galvanic couple possesses an important advantage within this space the medals, flatly laid, receive next operation would be to commence engraving

slightly less than the diameter of the medal. pointed gravers the design determined on. The over any other“ quantity" arrangement, insomuch their indentations. The compositor, sitting at a that design on the surface of the steel with small as the electricity has no tendency to escape table beside the machine, with his war office or tools prepared for the purpose. After, as may be through the earth from an imperfectly insulated Admiralty “copy” before him, and his alphabeti- supposed, a very considerable amount of sedentary wire. In the proposed arrangement any deficiency cally:arranged type near at hand, has set up in and tedious labour, and no ordinary exertion of of insulation can only interfere with the trans

the little case, about 4 inches in length, say the patience, there appears upon the surface of the

name of “Serjeant Major John Jackson, 60th steel a very perfect copy in intaglio of the original mission of the current by causing the wire to act Rifles,” or of Admiral Sir Charles Napier, H.M.S. design. Repeated impressions taken from this in as a voltaic velement, neutralising to a greater or | Undaunted.” Well, he next carefully places the I clay of a peculiar nature and colour-hard and

grayish white-enable the worker to test the finish screw, if the dies are of large size, and with our pages with sufficient clearness, and that our of his work and to examine the fineness of his lines modified intensity if the dies are small. Repeated labour in the preparation of the series of papers and the general effect they are likely to produce thumpings transfer the relief engraving of the on these subjects-of which this is the last—has as a coin. Satisfied at length that all is well, punch to the turned end of the die, which per- not been labour lost. and that retouchings would be but to “paint the haps, too, will require one or two annealings be- As it is possible that some of our readers may lily," the engraver gets all superfluous steel fore getting an intaglio impression perfectly re- require to put the machinery of the Mint in turned off in the lathe, and the diameter and presenting the device of the punch, This, how motion on their own accounts some day, we may height of this matrix, as it is now called, made ever, being accomplished satisfactorily in a num- tell them that in order to do so they are only reprecisely what he wishes them to be. Then comes ber of cases, a batch is sent off to the die-turning quired to be possessed of £10,000 worth of gold, a delicate and exceedingly important task—that shop. This is fitted with several lathes-it must and to observe the following (abstract of) rezulaof hardening and here practical difficulties arise be admitted rather antiquated-in which the tions :which, if not successfully overcome, may mar all superfluous steel is turned off and the dies, made 1st. The Mint receives gold bullion for coinage his previous labours.

of the proper diameter, height, and shape for fit- on Tuesdays, Thursdays, and Saturdays, from 12 Above all things, the engraved face of the ting the die holders of the coining presses. Next to 2. matrix must be protected from the action of fire they are hardened, then their faces are polished 2nd. Any persons intending to deliver gold into or water. In order to accomplish this protection by being held against a rapidly-running disc of the Mint for coinage must give a week's notice of various substances have been employed; but iron, and lastly, they are brought by tempering to their intention by letter addressed to the Master mixed oil and lamp black answers pretty well. a colour very much resembling the hue of our of the Mint. This composition, in proper proportions to form a southern corn-fields at this hour—a “dark straw." 3rd. Before delivery, the person delivering paste, is spread thinly over the engraved work of The average number of coins which a pair of dies the bullion must make a written statement in duthe matriz, which is next placed face downwards, should produce is 30,000, and more ought not to plicate on forms supplied him at the Mint, of and surrounded by powdered animal charcoal. be struck from them. The dies for medals are the marks of each ingot, the “report” thereon of It is heated to a particular temperature, and then got up in a manner closely resembling that in the assayer, upon whose assay he purchased it, plunged into cold water. In this it is kept, which coining dies are prepared, but of course from and the name of that assayer. held by a pair of tongs, in a state of agitation their larger size and bolder engraving, they give 4th. All the regulations witlr regard to weigh. until all ebullition ceases. Much of the art of in every stage of manufacture more trouble. ing through Mint office scales, entries of weights, die-hardening depends on practice, and nothing It may be said, too, that in the engraver's de- &c., as described in our account previously pub. short of extensive practice and a perfect know-partment at the Royal Mint there is a machine, lished of receipt of bullion from the Bank, must ledge of the chemical and mechanical properties of which we have seen, for copying, on a larger or be attended to. the steel to be dealt with can qualify workmen for smaller scale, an engraved device of any sort; 5th. A new assay by Mint assayer, and compathe duty. Constant practice in the same round for instance, supposing that, by some unhappy risons, with report of private assayer, necessary. of operations at the Mint no doubt ensures dispensation of Providence, a new monarch had 6th. The bullion must not be brittle. success in almost all cases of hardening. We succeeded to the throne of these realms, it 7th. Arbitration, if the assayers differ as to will suppose that it has so resulted in the case of would become necessary to issue a new set of the "betterness" or "worseness of the bullion. our imaginary cent matrix, which the engraver, coins, from the sovereign downwards.

Well,

sth. On the completion of the coin notice shall after tempering, pronounces to be good and ser- then, by aid of the copying machine in question, be sent to the importer, and a time fixed for its viceable. His next want is that of a "punch", which is of delicate construction and very delivery to him, when the same weight in gold not a copy of our facetious friend over the way, perfect in its details, the engraver, after de coins at the standard weight at which the ingots but a steel punch. In order to obtain this, another signing and engraving one obverse of large size, were received will be delivered to him without any piece of thesame steel bar which has so far"worked” would be enabled to produce a series of small charge whatever ! well is cut off, forged, turned, and prepared. Instead copies in steel down to the threepenny-piece size. The ninth and last clause of these regulations of having this will be punch turned flatly on the end, At one end of the machine he would fix his en- —which are not, for obvious reasons, given in it is made flatly conical, the apex being a point. graved die, and at the other a plain piece of steel. extenso, but which we shall be happy to supply to With this point uppermost the piece of softened By means of a treadle he would put both these in any would-be coiner—the ninth clause is the most steel is now placed on the solid bed of a heavy motion. He would next cause a steel pin important, because it demonstrates that gold press, to be worked by hand, though having its fastened at right angles to a square bar of iron, coinages are executed at the public expense. Some screw and fly-arms so arranged as that they be having a moveable fulcrum, to be brought forward member of the Rothschild family was, we believe, made to take three or four complete revolutions to the engraved surface he wishes to copy. This the only private individual who has had the upwards, and then be thrown down with great pin is kept up to its work by means of a weight honour and profit of working the Mint machinery momentum. The matrix, like the upper die in and lever. Āt the other end of the iron bar, as yet. the coining press, is fastened to the screw of the which is placed parallel with the front of the ma- Now, as regards the means of gaining admis. press, and as all is ready for the next stage of die chine, would be fixed a small cutting tool. This sion to the Royal Mint for the purpose of viewing making, we may suppose that the workmen have would, therefore, when the machine was kept in the operations going on there, and of which it is to raised the screw and matrix to the required height. motion, cut from the surface of the softened piece be feared our pen may not have conveyed so comAll is adjusted below, and the fly-arms released of steel just as much metal as the pin traversing plete a literary daugerreotype as might fain be spin round with great and increasing velocity un- over the whole engraved face of the die at the wished-as regards means of gaining admission, til the engraved face of the matrix meets in violent other end would allow; and, in fact, would copy we may furnish the principal regulations bearing contact the apex or point of the punch, and you it, on either a larger or smaller scale, in proportion thereon :might suppose that the engraver's work was mar- to the distances of the fulcrum from the cutting. “ Tickets of admission to view the Mint will red by the blow. Now the press rebounds, the tool and the guide-pin. The coinage of King only be given to persons known to the Master, or vorkien catch the fly-arms, and on examining William IV. is remarkable for the accurate profile to one of the principal officers of the Mint.” the matrix you find it none the worse. The of His Majesty upon all the pieces of money com- This regulation, it may be observed, receives a punch shows the valuable effect of the concussion, prising it. The copying machine here referred to very liberal interpretation at the hands of the prehowever, in having obtained to some extent, if not may be thanked for preserving so closely the sent Master of the Mint. “Persons coming with completely, a faithful copy in relief of the lineaments of the monarch. Mr. W. Wyon copied a ticket to view the Mint are to be received at engraved matrix. This latter may now indeed and engraved from a life-like bust by Chantry the principal entrance by the visitor's messenger, be laid aside, its mission for the present being the head for the William IV. half-crown, and all the who is to require the names of each party-which ended. The punch has, however, to be passed other dies for the coinage were the work of the copy- must not exceed six persons—to be written on the through the ordeal of hardening before becoming ing machine. Those who have not compared the back of the ticket, and then to conduct them in ready for its arduous task of giving impression to coins of thevarious denominations of this reign with succession round the following places, taking thonsands, and it may be tens of thousands of each other may well do so--microscopically, or care that the whole time devoted to one party money-making dies. The hardening and temper- otherwise—and they cannot fail to observe their does not exceed 45 minutes :-The silver meltinging in this instance are performed in a manner vraisemblance. Attached to the die department house, the gold melting-house, the rolling-room, precisely similar to that described above, and at of the Royal Mint there is a die museum, of the the adjusting-room, the cutting press-room, the the Mint failures are extremely rare. The punches contents of which a carefully-arranged chrono- marking-room, the annealing-room, the weigh. for both obverse and reverse sides of a coin are logical catalogue in MSS. exists. Visitors, on ap- ing machine-room, the coining press-room, the prepared in the same way, and once these are per- plication, are allowed to inspect the contents of die-multiplying press-room, and the die-turning fectly struck, hardened, tempered, and, perhaps, this numismatically interesting apartment. The shop.” A pretty considerable "round" for threeretouched by the engraver, they are in a condition oldest die in the place is of the date 1272, and it quarters of an hour with “running" explanations to allow dies to be multiplied from them almost is a rare specimen of the art of engraving at that by the messenger. The visitor's messenger enjoins al infinitum. Pieces of steel are now cut from remote era. The Simon petition crown die is among those under his care "not to touch anything in the bar and forged to the circular form, then the curiosities of the die museum of the Mint; but the rooms, and he in his turn is cautioned by returned fatly conical on one end, softened to the to catalogue all the specimens of this species of gulation not to touch any gratuity from any lowest point, and sent forward to the die multiply manufacture on its shelves would be to absorb visitor, nor allow any other person to do so. ing press. Here they are placed one by one on an amount of space which cannot be spared. Such are the main features of the regulations the bed of the press and underneath the punch, It is hoped that the main points in the art of made for the admission of strangers to the Mint, which is made to strike them with all the accu. Money-making, Medal-striking, and Die-manufac- and with them we say to those who have kindly mulated force of sundry revolutions of the weighted I turing have been revealed to the public through | followed us to the end-farewell!

THE AMERICAN SUBMARINE WAR

THE PATENT TRAVERSING DRILLING MACHINERY OF MESSRS. SHARP, VESSEL.

STEWART, AND CO. SOME months since, the Times startled many per

FIG I sons by an exciting account of a submarine war

THOSE who are acquainted with the Vessel. Mr. W. Delaney, of Chicago, the gentleman process of slotting holes through a who came here to work the plan, has obtained a

considerable thickness of wrought-iron

are well aware of the amount of trouble patent for the vessel, which he describes in his

and time which is expended upon it specification in the following terms :

under the old system of operation. “This invention has for its object improvements There is, perhaps, no work so expenin submarine boats or vessels, and in apparatus sive to the mechanical engineer as this, for working under water. A boat or vessel is and when complete it is but rarely constructed of plate iron, or it may be of wood or satisfactory. We have now the pleasure other material, supported by a frame of sufficient of laying before our readers a descripstrength. This boat or vessel is closed on all tion, with engravings, of a machine insides; it is elliptical, or rather egg-shaped in vented and manufactured by Messrs. transverse section, and runs off to a point at both Sharp, Stewart, and Co., of Manchester, ends; one end being, however, more rounded than adapted to the performance of the work the other, and its length is several times its in question. It does its work with such greatest diameter; and at the top, bottom, and

success that the cost of labour has been sides four or other number of keels are fixed to reduced some 90 per cent., and at the keep the vessel steady in the water. Within the same time almost mathematical cerboat or vessel are two strong metal tanks, into

tainty has been secured. As an inone of which air can be forced by an air-pump. stance: a slot-hole 6 inches long, 1 wide, This tank is connected with the second tank and 54 inches deep, formed in the orby a pipe furnished with a cock, and the dinary manner, would be produced in second tank also communicates by a pipe with 32 hours at a cost of £1 28. 2d., three the water exterior of the boat or vessel; so files being expended upon the work. that a person within the boat or vessel can fill | This can now be effected by means of this tank with water, and thus increase the weight the traversing drilling machine in less of the boat or vessel so as to cause it to sink, or than 14 hours, at a cost of only 2 shillby allowing the air to pass from the air-tank to ings, in the case of one workman having the water-tank, the water may be again ejected, three such drills to attend to. With so as to lighten the vessel sufficiently to cause it this fact before us it will be needless for to rise to the surface. Through one end of the

FICH us to expatiate further upon the ad. vessel a hollow shaft passes by a ball and socket- vantages of such a system. We proceed joint, and on this shaft a rudder is mounted. Be therefore, to describe and illustrate the yond the rudder there is a screw propeller, which machine itself, and shall then enuis driven from the interior by an axis passing merate the various purposes to which, through the hollow. shatt of the rudder. By this up to the present time, it has been propeller the vessel may be propelled in any de- applied. sired direction. A similar screw may be placed at The general action of the ordinary the other end of the vessel if thought desirable. drilling machine is well understood. The persons within the boat or vessel are supplied The constant revolution of two paring with air from time to time from the air-tank, and edges round a common centre is emthe vitiated air is allowed to escape from a cock ployed in such machines to produce a into the exterior water. Double doors are formed vertical hole. If, then, instead of giving in the top, bottom, and sides of the vessel, and the tool a simple vertical feed, we endue these may be opened beneath the water to allow it with a reciprocating motion, altering of ballast being passed out when necessary, and the form of its end so as to produce a for other purposes. In conjunction with this boat double rounded nose with cutting or vessel a diving armour is employed, so that edges, and taking away the centre when the boat or vessel arrives at a point where clearing point, which is not now rework is to be done a diver may leave the same quired, we are enabled to form a long to do whatever may be required. This armour is slotted hole instead of a circular one. formed of metal, the moving parts being so fitted The vertical feed in this case must of and jointed together that the pressure of the water course be given at each end of the may be sustained by the armour and not commu- traverse, so as to insure the plane of the nicated to the body of the diver. Through the cut being horizontal from end to end. sides of the armour a number of tongs pass, with Fig. 1 shows the various forms of the which the diver can hold any tool with which he tools made for use in this machine. The has to work, or any other article. These tongs first two are roughing tools, for small pass through ball and socket joints, and are ar- or large diameters. It will be noticed ranged to be readily acted on from the interior that in the large size the tools are adof the armour, so as cause them to open and justable and secured by means of set close. Into the ball and socket joints any tools screws at their lower ends. The third may be fitted, and these also serve to pass short and fourth tools shown are rose bits tools from the exterior to the interior of the ar- whose serrated edges are curved; these mour as may be required. In order to facilitate are used for finishing the work. Plans the movement of the diver a screw propeller is also of all the tools are shown below attached to the front of the armour. The diver the elevations. The roughing-out tools on the so that its projecting bearing can be shifted, and is supplied with air from the air-tank within the average require sharpening but once in the week, the reciprocation varied at pleasure. The spindle boat or vessel, or otherwise, and he also carries and the rose bits but once in six weeks. Having of the horizontal plate is driven by the lower on his back a reservoir of compressed air, which investigated the form of the tools in use, we pass shaft, which is figured A, by means of speed enables him temporarily to disconnect the hose if on to the consideration of the machine itself, and pulleys from the upper or first driving shaft B. required.' The rope by which the diver is lowered its mode of action.

Of course

a regular velocity in the traverse is also so arranged that the diver can disconnect it In fig. 2 we have given a perspective view of cannot be attained by a simple crank motion, as if he desires. Exterior of the armour is an elastic one of the single traversing drilling machines ; it the speed will gradually diminish to nothing at bag, into which the diver admits air, so as to in- consists of a strong frame of cast-iron after the the extremities of the traverse; but this is date it when he wishes to use the surface. A lamp fashion of a lathe bed supported upon a standard obviated in a very ingenious manner by the introis mounted within the armour, and in front of the at each end. The top surface of this bed is duction of a pair of eccentric-toothed wheels such same is a bull's eye, which concentrates the light planed true, and fitted with a hollow or box as are shown in fig. 3. These are so arranged on objects in front of the diver. The submarine boat standard carrying the drilling spindle, which is that the proportion of their working diameters or vessel is in some cases fitted with steam-engines, worked in the ordinary manner by bevel wheels; varies so as to overcome the difficulty which to propel it more rapidly when the boat or.vessel this standard is caused to travel backwards and would otherwise arise. The position of the conis at the surface of the water. The same power forwards upon the bed by the circular motion of a necting rod is shown by the letters A, B, in Fig. also serves to pump air into the tank,”

horizontal plate, which is slotted and graduated 3. Underneath the horizontal plate, which is

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