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placed a weight which is made to close the valve represents an eccentric, with a great improvement, attached to the same eccentric, for driving pumps or again as the cam revolves. The diameter of the patented by Timothy Keeler and Geo. S. Avery, of independent lathes. Offsets in eccentric rods can be fly-wheel is 20ft. 6in., and the size of the rim is Danbury, Conn., by which oscillation is obtained. frequently dispensed with, and the improvement is 16in. by 7in. The crank shaft journals are each The eccentric or cam is usually keyed rigidly upon a applicable and useful for feed motions, and in many ift. 5in. long, by lft. diameter; the length of the shaft, and the eccentric strap is fitted to work easily cases which engineers will not be slow to discover. crank is 5ft. 44in., and the length of the sweep röd upon it; the rod, known as the eccentric rod, is atis 27ft. Sin. The blowing cylinders are each 100in. rectilinear motion; but on reference to the ac

tached to this strap, and gets a steady reciprocating in diameter and 8ft. 6in. strokc; the valves are companying engravings, figs. 1 and 2, it will be seen

THE DETERIORATION OF MARINE made with leather and a plate of sheet iron at the that by the attachmeut of the exterior band, F, the

BOILERS. back; the piston is constructed with angle irons eccentric rod has perfect freedom to swing, while and two collars of leather turned up in the usual

which yet remaining to be explained by satisway. The distance between the centres of the

factory hypotheses, deserve to rank as mysteries. cylinders is 26ft. 8in., and the length of the beam

FIG.1.

Among these we may cite two which are sufficiently between centres is 30ft. lin. The tuyere pump is

remarkable. One is the exceedingly, and in some of the bucket-and-plunger variety, with a plunger

cases alarmingly, rapid deterioration of marine 9in. diameter. From the centre of the beam to

boilers by corrosion; the other is the failure by the floor line the distance is 21ft. 8in. ; the depth

** coming down ” of the crown plates of furnaces. of the beam in the centre is 5ft. and at the ends

The first presents itself not unfrequently under con2ft. The pressure of steam at which the engines

ditions and in a way which renders it absolutely inare worked is usually about 30lb. to the square

explicable by any sensible theory. Attacking one inch.

side of the steam space, the other remains untouched. In boilers similar in every respect, corrosion takes

place in one on the right side, in another in the left. OSCILLATING OR VARIABLE ECCENTRIC

Now it is the portion nearest the funnel which MOTION.

suffers most ; again it is a single plate furthest FIC.2.

from the uptake that is eaten away. Î'he diseaseTHE term eccentric is applied in general to all such TAE

for such we may term it-appears under different curves as are composed of points situated at un

forms. At one time the plates attacked are deeply equal distances from a central point or axis. The

pitted, at another the iron exfoliates in flakes. Mr. ellipse (the curve called the heart, which is much

Bourne attributes steam-space corrosion to the action used in the traverse motion of spinning frames,

of superheated steam. We confess that to us the and even the circle itself, when supposed to be

theory appears untenable. No marked difference fixed upon an axis which does not pass through its

can exist in the temperatures present in various contre), are examples of its eccentric curves. The

portions of the boiler; and unless it can be proved object of such curves, that are of frequent occurrence

that superheated steam is present in one place and in machinery, is to convert a rotary into a reciprocat

not in another, it is difficult to see why one plate ing, rectilinear motion. The cam known among

should suffer more than another. It is true that engineers and machinists as an eccentric, is a plate

superheated steam much hotter than 280deg. disenteor palley, turning on a shaft out of its centre. When

grates cast iron ; but it has yet to be demonstrated keyed upon a shaft, we speak of the two centres as

that any corrosive effect of a similar character, or the centre formation and the centre of revolution by

indeed of any kind, is exercised on wrought iron. means of a surrounding strap, to which is attached a the eccentric cam, A, is keyed firmly to the shaft, and The most probable solution of the problem is found rod, we get the reciprocating rectilinear motion to revolves in its true line of motion. Also, by this in the effect produced by pure distilled water on the valves of steam engines; the same motion is arrangement, the eccentric rod may be set, if required, wrought iron. It is now perfectly well known that common to pumps, feed gear of lathes, &c., and at almost any angle to the line of eccentric motion, distilled water from surface condensers rapidly familiar to engineers and machinists who know that and still work freely. By this means, marble, wood, destroys the plates of boilers, and in order to prothe degree of eccentricity or extent of throw given &c., may be sawed or cut, of a tapering or angular tect them it is necessary that sufficient salt water by an eccentric is equal to twice the distance between form, without changing or moving the body being be admitted from time to time to maintain a thin its centres of formation and revolution. The annexed cut; or angular or irregular grooves in iron, &c., coat of scale. If it can be demonstrated that pure engraving, for which with this description we are may be cut or planed with facility. Also, by this water is brought into contact with the plates of a indebted to the American “ Journal of Mining," arrangement, two or more eccentric rods, B, may be steam chest we can at once establish a reasonable

theory to account for their corrosion, as like causes quietly in dock, with not half the pressure in the has, however, to be toughened, for which there is an usually produce like effects. Now, marine boilers boilers which they had carried with ease before, and extra charge. The private assayers of California, are alternately hard worked and left at rest when with fires nearly out. It has yet to be shown that before the establishment of a Government Assay the fires are drawn; as the boiler cools down pure pumping in cold water under such conditions of Office there, used to make no charge for the assay, distilled water will be precipitated on the steam heat and pressure can produce a collapse. The taking their pay out of the drippings from the cruchest plates hy the condensation of the steam, and wholo story—for the truth of which we can vouch- cibles. The Government assayers account for the the water may be present in sufficient quantity, and is highly instructive and interesting. The case is entire weight of the deposit. the precipitating process may be sufficiently often nearly without an exact parallel, so far as we are The depositor having received the full value of repeated to render the corrosion with which we are aware ; and for the present wo prefer that our his deposit, the latter of course becomes the property dealing explicable. We do not assert that this readers should draw their own conclusions. It is of the Government, and it now has to undergo a theory and it is no more-is perfectly satisfactory, quite possible that some among the number can cite process called “parting” before it is sent to the but we believe it to be the best yet broached. cases tending to throw a light on what at present Mint, or used in any way for commercial purposes.

A still more vexatious, and in many cases not less is an exceedingly curious episode in the history of In parting gold, silver is added the proportion of mysterious, kind of injury is the second we have marine boiler engineering.--The Engineer." about two parts in weight of silver to one of gold. named in the first lines of this article. Furnace

Formerly no account was taken of the silver already crowns come down not unfrequently while there is

in the gold, but Mr. Mason, in charge of the melting plenty of water to all appearance in a boiler ; while,

and refining department, found that a great saving in a word, no reasons within mortal ken exist for THE UNITED STATES ASSAY OFFICE IN might have been effected if it was first ascertained their failure. We remember one instance in which

how much silver the gold bullion already contained. the crowns of the furnaces in a large steamer, obsti

NEW YORK.

This practice is now carried out, and instead of nately refused to keep their proper form. After DJOINING the sub-treasury in Wall-street is a invariably adding two parts of silver to one of gold, many repairs the attempt to keep them right was granite building of modest appearance, bearing only sufficient silver is added to make the proporgiven up in disgust, and the boilers were worked over its entrance the words “Assay Oflice." It is tions above stated. There is thus a saving, by Mr. until they were worn out with the furnace crowns fitted up in the same style as a broker's office, and Mason's method, of about 30 per cent in the material, all more or less out of shape. After they had come three or four clerks appear to be quite able to and in one year the sum of 22,000 dollars was saved. down to a certain point they got no worse, and gave transact all the business pertaining to this Bureau The mixture of gold and silver is next melted, no trouble. In this case the circulation was bad, without over exerting themselves. In fact, it thoroughly mixed, and poured into water, by which and the sinking of the furnace crowns appeared to would not appear at a first glance that much business it is granulated. The granules are placed in porceimprove it by giving more space over them. The is ever transacted there ; yet there from 14,000,000 lain jars containing nitric acid. Heat is then applied, boilers were defective in design, and the failure to 15,000,000 dollars of the precious metals are re- and as the acid boils, the yellow fumes which our appeared to be, as physicians say of certain dis-ceived and accounted for during the year. The readers have doubtless so often seen proceeding orders of the human system, an effort of nature. larger portion of this is in the form of gold dust from the chimney of the Assay Office, are given off.

But even in boilers carefully worked and of good from California, Nevada, Montana, and Idaho. Much This process goes on for about twenty-four hours, design furnace crowns sometimes sink without pre- the larger portion of all the bullion received is either when the jars are emptied, and in the bottom is found vious warning under the most unaccountable cir- in the form of dust, grains, bars, or amalgam. A a brown substance resembling mud or anything else cumstances. Within the last few weeks a case in comparatively small quantity comes in the shape of upon earth rather than “gold-glittering gold.” It point came under our notice which presents many gold and silver plate, watch cases, foreign coin, and is, in fact, however, pure gold, or at least, very nearly points of interest. A new steamer, plying between ornaments. These are sent in by jewellers or pri- so. The silver has been dissolved by the nitric acid, Liverpool and Dublin, was fitted up with two vate parties to be re-melted, for plate, watch cases, and is in solution. It is carefully put aside for future boilers, one tubular of the ordinary construction, the and ornaments change their fashion like other things treatment, for in the Assay Office nothing must other a flue boiler on a novel principle. The two of less value, and have to be remodelled to be sale- be lost or wasted. The brown substance found at boilers were introduced into the same boat in order able.

the bottom of the jars is placed in large wooden tubs to test the relative efficiency of the old and the new Few persons are aware of the actual quantity of and washed by percolation in warm water until all systems. During the first month the ship was on gold produced by our mines since their first dis- traces of acid have disappeared, and it is said to be her station she did, as is often the case under covery. In a recent official report this amount is "sweet.", similar circumstances, a good deal of racing with placed, in round numbers, at 1,000,000,000 dollars. The gold is then of .940 fineness. Formerly it was older boats, in which she always won. Hard firing Since 1849, California has produced' 900,000,000 subjected to a second boiling in nitric acid, which of course was not unknown on board her, and after dollars. Her productive powers, however, for the left it about .993 fineness, but by the process at a couple of weeks one furnace crown came down very last thirteen years have steadily decreased, and for present in vogue it is treated with sulphuric acid, by slightly in the tubular boiler, the other boiler remain- 1869 the estimate is only 25,000,000 dollars. Mon which a fineness of .998 is attained. This is termed ing all right. Hardly a month since the ship-wetana has produced 65,000,000 dollars; Idaho, pure gold although it is not actually so, but to dedo not at present feel ourselves at liberty to mention 45,000,000 dollars; Colorado, 25,000,000 dollars. prive it of the two parts of alloy it now contains names-came into Liverpool and hauled alongside The estimated production of Nevada in 1869 is would involve an expenditure of time, money, and the wharf. At this time her firedoors were open, placed at 20,000,000 dollars ; of Montana, 12,000,000 trouble altogether useless. After its treatment with the fires very low, the safety valves blowing freely, dollars. It is believed that not more than 50,000 sulphuric acid, the gold, which still looks more like and not 1016. steam in the boiler, the regular pres- persons are now engaged in mining in this country-red mud than a precious metal, is again washed until sure being 201b. per square inch. The engineer a considerable falling off from the numbers of sweet." It has now a reddish yellow hue. After gave orders that some water should be blown out, previous years.

being dried, it is taken to a hydraulic press, where it and the boiler pumped up with the donkey engine. The deposits received having been carefully is made into “cheeses," so called from the colour He then went on deck, and had not been there ten weighed and a certificate given, are numbered and and shape. The cheese made in the Assay Office minutes when he was called down to the stokehole, sent at once to the melting room, a spacious apart- is richer far than the most fertile vales of Gloucester as something was wrong. On looking into the four ment provided with furnaces, tanks, &c., and floored evero produced. Each “cheese" is but 13in. in furnaces of the flue boiler he found that the crown with iron tiles. Each deposit, or as much of it as diameter, but it is worth about 20,000 dollars. These plates of all had come down to an extent very little can be conveniently handled at once, is placed in a cheeses aro baked in an oven heated by steam until short of absolute collapse; not twenty minutes crucible, and, as soon as melted, is poured into iron all remaining moisture is expelled, when they are before they were all right under 20]b. steam. moulds. If the deposit is of gold, two pieces are remelted, cast into bars or bricks, assayed and

Our readers will, we think, join with us in saying cut from the lump and set aside for the assayer. stamped with the weight, fineness, and value. And that in this case there is much that is sufficiently re If of silver, a small portion of the fluid metal is now they look like gold indeed. markable. There was no reason to think, from the dropped into water, which granulates it, and these

The reader will remember that nitric acid poured previous performance of the boiler in question, that granules are used by the assayer. The crucibles over the gold and silver granules, in the porcelain the circulation was deficient in any respect ; and it are carefully scraped after being used, so that not a jars, and now containing a large quantity of silver is next to certain that it must have been sufficient particle of the metal is lost, for the assayer, it must in solution, has yet to be disposed of. A solution of with low firds and blowing safety valves if it sufficed be understood, has to account for every grain of the chloride of sodium-common salt-is first added to for hard firing and high pressures. Was there time metal received.

the solution, and a deposit of white powder is the under the conditions for the furnace crowns to About 7 grains of gold are used in each assay. result. This powder is chloride of silver. The next become red-hot, even though the circulation was This small quantity, with the right proportion of process is to free the chlorine from the silver, and bad? We think not. One explanation assigned silver, which is estimated by the assayer with an this is done by placing it in vats with granules of was that all the water, or nearly all, had boen blown accuracy attained by incessant practice, is placed in zinc. The chlorine and zinc readily combine, and out, and that the introduction of cold water brought a cupel - a cup of calcined bone-and deposited in a the silver is set free in the form of a light grey about the catastrophe. This theory is not sup- small furnace heated to redness. A strong current powder. This, like the gold, is washed, pressed, ported by good evidence; the stoker in charge of air passes over the contents of the cupel, oxydiz- and formed into cheeses" worth 800 dollars each. asserted that the water was not blown low enough ing the lead. The oxide dissolves the oxides of the These are melted, weighed, stamped, and ready to to strip the furnace crowns, and, indeed, these lie so other base metals, which are absorbed by the cupel, be disposed of as occasion may require. The silver low that had they been bared the boiler must have and the result is a button of puro silver and gold obtained by the above process contains but one part been nearly emptied. Again, if the water had been This button, after being hammered and rolled, is of alloy in 1,000. Some silver is so pure that it blown too low, would not the flue crowns, especially placed in a bottle partly filled with nitric acid, which requires no * parting," and, after being assayed, is at the back of the boiler, being much longer exposed is set in a sand bath. This acid dissolves the silver, sent at once to the Mint. The Assay Office was than the furnace crowns, have manifested some leaving the gold untouched. When the process is established in this city in October, 1854, and since signs of overheating? We think so; but no trace finished, the pure gold left in the cupel resembles that time over 100,000,000 dollars have passed of injury was to be found on them. Under the cir- tinder. 'It is then annealed, rendered into a com- through the hands of its officers.—"Scientific cumstances, we are driven to conclude that the pact coil, called the cornet," and weighed. The American.” pumping in of cold water does not suffice to account weight gives the exact amount of pure gold. Two for the injury. According to this theory it is pieces were, it will be remembered, taken from the THE “Stationer" states that about forty years ago assumed that the furnace crowns were laid bare by metal after it had been melted. Each of these pieces there lived at Brighton a bookseller and stationer of priming while at sea, and that they thon came down, is assayed separately, and the results must, of the name of S. K. Brewer, and he used to place in but that the injury was not discovered till long course, agrec. If they should not do so, it is evident his shop window piles of paper, beginning at the afterwards, when the introduction of cold water that a mistako must have occurred somewhere, and largest up to the then smallest size, 16mo; but to made the seams leak. In considering this explana- the whole process has to be repeated.

finish off the pile he cut cards so as to bring them we have to bear in mind that the furnace crown, on As soon as the assays are completed, the assayer up to a point." Ladies used to go in and ask for that which the cold fluid impinged most directly, should reports to the Assistant Treasurer of the United dear little paper,” which induced him to cut paper sifier most, but, so far as we can learn, no such States, and on his report the depositor is paid. If in small sizes. Then came the difficulty of the effect was produced, nor has it been proved that any he desires to receive gold coin, one-half of one per place for address, and the result was he invented the considerable quantity of cold water was ever cent. is charged. For gold bars, which are handier envelope, and had metal plates made for cutting them pumped in. Nor is it likely that the crowns could for shipment, he has to pay six cents for 100 dollars. to shape and sizes. This just pleased the ladies, and have come down on the irip without discovery. For every ounce of pure gold which his deposit has orders came to him for the little paper and envelopes The entire subject is fraught with mystery. Here yielded, he receives 20-672 dollars, less the charges from all parts. This at length became such a dewe have a boiler which works satisfactorily for stated above. Depositors of silver receive its full mand upon his time, that he got Dobbs and Co., of weeks, carrying 2015. steam, and when hard fired value, less what is called the “parting charge," London, to make them for him. Such was the begiving out without a moment's notice, when lying, which is about five cents per ounce. Brittle metall ginning of the envelope trade.

which are thus withdrawn from the regenerators THE SIEMENS FURNACE.

are a positive gain to the heat of the furnace, hocause, having been in contact with comparatively cold metal, they would be at a heat inferior to that of the upper portions of the regenerators, and would therefore only lower their temperatures.

As the bars sink in the hoppers by their gravity, they are followed up by additional bars until the metal charged amounts to about three tons, all of which will be rendered fluid within about four hours from the time of commencing the charge. The metallic bath is tested from time to time by the introduction of a bar through one of tho front doors of the furnace, and if the bath should become thick before the end of the operation, although the heat has been maintained, will be necessary to introduce an additional quantity of pig motal. All the metal being liquid, a sample is taken out by means of a small iron ladle, and plunged into cold water while still red-hot. In breaking this sample upon an anvil, the temper and quality of the metal may be fairly judged. Its fracture should be bright and crystalline, betokening a very small proportion of carbon (not exceeding •1 per cent.), and the metal should be tough and malleable, notwithstanding its sudden refrigeration. From 5 per cent. to 8 per cent. of spiegeleisen (containing not less than 9 per cent. of manganese) is thereupon charged through the side openings upon the bank of the furnace, and allowed to melt down into the bath, which is then stirred and made ready for tapping in the manner before described. The amount of carbon introduced with the spiegeleisen determines the temper of the steel produced, the manganese being necessary to prevent redshortness, unless Swedish or Styrian iron is used.

When old iron rails or scrap of inferior quality к

are charged, the addition of manganese does not suffice to effect the necessary purification of the steel produced, but the perfectly liquid condition of the bath, together with the unlimited time available for chemical reaction, offer extraordinary

advantages for the introduction of such materials of the furnace must be sufficient to fuse the sur as may be found to combine with sulphur, phosTHE SIEMENS FURNACE APPLIED TO THE face of each layer, that is to say, it must rather ex- phorus, silicon, or arsenic, which are the usual MANUFACTURE OF CAST STEEL.

ceed a welding heat to begin with, and rise to a antagonists to be dealt with. The experiments

full steel-melting heat at the end of the operation, which I have been able to institute in this direction a lecture to the fellows of the Chemical So- most layers. Care must be taken that the surface obtained most beneficial results from the introciety on the application of his furnace to the manu- of the bath assumes the form of a shallow basin, duction into the bath of litharge, in conjunction facture of cast steel. Mr. Siemens' able lecture being deepest near the tap hole. Some white with oxidizing salts containing strong bases, such dealt at great length with the theory of steel sands, such as that from Gornal, near Birmingham, as the alkaline nitrates, chromates, chlorates, making, and with the more remarkable features in will set under these circumstances into a hard im- stannates, titanates, &c. The choice of the reagents its history; he also described minutely the work- pervious crust, capable of surviving from twenty and the quantity to be employed depend, naturally, ing and construction of his furnace. The most to thirty charges of liquid steel, without requiring upon the quality and quantity of objectional interesting portion of the lecture referred to the material repairs. If no natural sand of proper matter to be removed. By the aid of the process production of steel direct from the oro •and the quality is available, white sand, such as Fontaine- just described it will be possible to convert old iron fusion of steel in an open bed, which we repro- bleau sand, may be mixed intimately with about rails into steel rails of sufficiently good quality duce here. Our engraving illustrates Mr. Siemens' 25 per cent. of common red sand, to obtain the at a cost scarcely exceeding that of re-rolling observations. same results.

them into fresh iron rails. The non-expensive The furnace employed for the fusion of steel on In tapping the furnace the loose sand near the nature of the process may be judged by the fact the open bed is similar in shape to a reheating or tapping hole is removed, when the lower surface of that extremely little labour is required in conductpuddling furnace; the direction of the flame is the hard crust will be reached. The lowest point ing it ; that the loss of metal does not exceed from from end to end; and the regenerators are placed of this surface is thereupon pierced by means of 5 to 6 per cent., and that from 10cwt. to 12cwt. of transversely below the bed, which is supported on a pointed bar, upon the withdrawal of which the coal suffices to produce a ton of cast steel. iron plates, kept cool by a current of air. The air fluid metal runs out from the hottest and deepest Although I have succeeded in producing malleenters beneath the bed plates in front, and escapes portion of the bath into the ladle in front of the able stoel from ordinary English iron by this proby two ventilating shafts at the back of the fur- furnace.

cess, it would be unreasonable to expect steel of Daces near the ends. This cooling of the bed is M. Le Chatelier now proposes to mix the natural really high quality in using those materials which very necessary to keep the slag or melted metal bauxite, of which the bottom of the experimental are already contaminated in the blast furnace; and from finding its way through into the regenerator furnace at the works of MM. Boignes, Rambourg, I am sanguine in the expectation of producing cast chambers. The upper part of the furnace is built and Co., near Montlucon, was first made, with steel superior in quality, and at a low cost, directly entirely of Dinas brick, consisting of nearly puro about 1 por cent. of chloride of calcium in solu- from the better description of ores, such as the silica, which is the only material, of those practi- tion, to calcine the mixture and to form it into hæmatites, magnetic oxides, and the spathic cally available on a large scale, that I have found moulded masses of highly refractory material. Acarbonates. My experiments in this direction to resist the intense heat at which steel-melting hard bottom being thus prepared, and the heat of extend over several years ; and last year I sent a furnaces are worked; but though it withstands por- the furnace being raised to whiteness, it is ready to few bars of steel produced from hæmatite ore to fectly the temperature required for the fusion of receive the materials to be melted. If those mate- the French Exhibition, which had stood a high the mildest steel, even this is melted easily if the rials consist of bar iron, or of old iron and steel test in Kirkaldy's machine. A "grand prix ” was furnace is pushed to a still higher heat.

rails, they are cut into lengths of about 6ft., and awarded for this and other applications of the reThere are three doors in the front of the fur- are introduced into the furnace through slanting gonerative gas furnaces. Having tried various nace, one in the centre immediately over the tap hoppers B from the elevated pla at the back, modifications of the furnace I have arrived at a hole and two near the bridges, through which the so that their ends rest upon the sand bottom form- form of apparatus not dissimilar to the one just bed can be repaired when necessary, and ingot ing the bath.

described. The furnace and tapping arrangements ends and other heavy scraps may be charged in. If the capacity of the furnace is such that charges are, indeed, the same, except that for the slanting Sloping shoots are provided at the back of the of 3 tons can be formed, about 6cwt. of grey pig hoppers vertical hoppers over the middle of the furnace, through which long bars, such as old iron is introduced through the ports or short bath are substituted, in which the ore gradually rails, may be conveniently charged, and beneath hoppers below the main charging hoppers before descends. Each hopper is formed of a cast-iron these are openings for charging the pig iron. The mentioned. As soon as a bath of pig metal is pipe, supporting a clay pipe, which is attached to upper ends of the shoots is on a level with an formed, the heated ends of the rails or bars begin it by means of a bayonet-joint, and reaches down elevated charging platform behind the furnace. to dissolve, causing the bars gradually to descend. into the furnace, while the cast-iron pipe rests with The bottom of the furnace is formed of siliceous By partially closing the mouths of the charging its flange on the charging platform. sand, which answers exceedingly well if properly hoppers a regulated quantity, flame is allowed A fire space is provided surrounding each selected and treated.

to escape from the furnace, in order to heat the hopper, through which flame ascends from the Instead of putting moist sand into the cold fur- descending bars of metal previous to their entry furnace, and is allowed to escape in regulated nace, as is usually done in preparing the bottoms into the melting-chamber, the object being to quantities near the upper extremity of the retort, of furnaces for heating or melting iron or copper, maintain the high temperature of the furnace, not- the object being to heat the latter and the ore conI dry the sand and introduce it into the hot fur- withstanding the constant introduction of cold tained in it to a red heat. A wrought-iron pipe nace, in layers of about lin. thickness. The heat metal. The escaping products of combustion descends into each hopper from a general gas

[graphic]

tube above, through which a current of ordinary the vibration of the ground under his feet, caused by ances are necessary. These are located in the maproducer gas is forced in amongst the heated ore. the incessant blows of the steam hammers; and a chino shop, an apartment 150ft. in length and 50ft. The propulsion of the gas is effected most con- peep inside reveals a scene of extraordinary activity. in breadth, both sides of which are lined with turnveniently by means of a steam jet in the gas tube We shall briefly describe what came under our ing lathes, slotting and boring machines, and such

One of the turning leading from the main gas channel to the top of the observation as we were shown through the work by like, of extraordinary size.

one of the proprietors, and thus endeavour to convey lathes is said to be the largest in the world ; and furnace, care being taken to effect a total con

some idea of what goes on in the place. The first some idea of its dimensions and form may be obdensation of the steam by passing the gas finally department we entered was the rolling mill, which tained from the fact that the crank shaft of the through a small scrubber, in which water trickles is 300ft. in length, and 150ft. in breadth. At one end "Monarch," though weighing thirty-two tons, was over pieces of coke. In this way the gas is at the of the mill are arrangedtwenty-two puddling furnaces, turned in it without taxing its capabilities to the same time purified from sulphurous acid, the sul- and half-a-dozen re-heating furnaces. The rolling utmost. Some of the iron shavings lying about the phur of which might otherwise combine with the and other machines are driven by a pair of horizontal vast machine were fully lin. broad and kin. thick ; reduced ore.

engines of 300-horse power. The Ay-wheel of the yet these were turned off with apparently as little

engines is eighteen tons in weight, and it makes 100 effort as if the material had been wood instead of iron. The furnace is charged in the following manner: revolutions in a minute. The steam is supplied by One of the boring machines is sufficiently powerful - The hoppers and gas pipes being placed in posi- fourteen vertical boilers heated from the puddling to drill a hole loin. in diameter through a solid tion, about a {cwt. of charcoal is charged through furnaces. The iron is first rolled into bars, then cut block of iron; and the largest slotting machine can each hopper to form a basis for the ore with which up, re-heated, and either rolled into ship and boiler send off chips a pound or two in weight. When the these are afterwards filled. About 10cwt. of pig plates or wrought into pieces suitable for the forge. work leaves this department, it is generally quite metal is charged through the ports at the back or At one time the firm devoted attention to the making ready for being fitted into its place. This firm front of the furnace, which, upon being melted, of armour plates, and their specimens stood the test pay nearly £40,000 a-year in wages, and in all deforms a metallic bath' below the hoppers. In the of competition with those of English makers most partments of the establishment, 15,000 tons of iron, meantime the ore in the lower parts of the hoppers, creditably; and, but for the want of convenience for and 60,000 tons of coal are annually used.—“The being heated in an atmosphere of reducing gas, distant Messrs. Rigby and Beardmore would have

carrying the plates-the nearest railway being a mile Ironmonger." has become partially reduced into metal sponge, obtained a fair share of patronage from our own which, in reaching the metallic bath, is readily and other governments. The machines are capable dissolved in it, making room for the descent of the of producing plates 8in. thick, and some of the plates superincumbent ore, which is likewise reduced in made of that thickness have weighed twelve tons each. THE RAILWAY MOVEMENT IN AMERICA. its descent, and dissolved in due courso, fresh ore At some of the puddling furnaces a new invention being continually supplied on the charging plat- was being tested, and we were told that the most HERE are probably now in operation at least form. The dissolution of the reduced ore proceeds satisfactory results were being produced by it. Its with extraordinary rapidity, but is practically object is to hasten and render more perfect the about one mile of railway to every million of inhablimited by the timo necessary to effect the reduc- puddling process, by injecting a current of air at itants, and though this would seem a fair amouut of tion of the ore in the hopper, which occupies high pressure into the furnace. This is done by supply, yet the construction movement still goes on several hours. It is, however, not essential that making the puddling bar hollow and affixing to the with unabated force. From the fact that the great the ore should be thoroughly reduced before reach with a powerful air-pump. The patentee is Mr. seaboard, and in the contiguous Central and Northing the bath, because the carbon contained in the Richardson, of Glasgow; and the advantages gained western States, it would be supposed that the movecast metal serves also to complete the operation. by the contrivance are that a charge of the furnacement in these localities would have about ceased ;

I prefer to employ a mixture of hæmatite and can be puddled in fifteen minutes less than the time but the facts show the contrary. In the New spathic ore, containing the elements for forming a required by the usual process, and that the iron pro- England States and the States of New York there is

now being constructed, or at least commenced, an fusible slag, which will accumulate on the surface duced is purer and tougher. of the metallic bath, and may be from time to

The forge or smithy is nearly as large as the amount of full 1,500 miles, at an estimated cost of at time removed through the centre door. If the ore kind. There are two steam cranes, capable of lifting lines, like that to Hudson River from Boston, and

rolling-mill, and its fittings are of the most gigantic least 60,000,000 dollars. Some of these are extension contains any silica it is necessary to add somo lime fifty tons each, four, forty tons each; and four, the line from Oswego from Rondout ; others are or other fluxing materials, but it is desirable to twelve tons each ; and these are so arranged that connecting or cross lines, and many others spur or employ ores containing little gangue, in order not a shaft or other piece of work may be passed from branch lines, for merely local convenience. There to encumber the furnace with slag, reserving the one to the other all over the shop. There are fifteen seems to be no limit to the demand in the thickly poorer ores for the blast furnace. The ore should, steam hammers, varying in weight from seven tons settled communities, and as long as the capital can moreover, be in pieces ranging from the size of a to two. Finished shafts-that is finished so far as be procured and charters obtained, we must expect pea to that of a walnut, in order to be pervious to the hammering was concerned-were lying about railway construction to continue until the entire the reducing gases. If ores in the form of powder in all directions, and so delicately had these been land is grid-ironed into very narrow spaces. We are employed, it is necessary to mix them with operated upon by the hammers that the surfaces are now speaking of the more densely settled states abont 10 per cent. by weight of light carbonaceous almost superfluous. Yet they were destined before the lakes ; but, as the population increases in the

were so smooth that turning would seem to be between the seaboard and the Mississippi River, and materials, such as dry peat, wood, or charcoal.

leaving the place to be fitted into a lathe and turned states away from the seaboard, we shall find the The metallic bath having sufficiently increased with the greatest exactness. In the heating furnaces same state of things to exist. The main or through in the course of from threo to four hours, the and under the hammers were a dozen more heavy lines are now pretty well indicated, but more will supply of oro is stopped, and that contained in the jobs in the shape of crank-shafts, rudder frames, yet be added, and the branch or spur lines will, in hoppers is allowed to sink. Before the hoppers are and such like ; and as these were in all stages of all probability, be as thick as they are in New

With a population of 37,000,000, the empty, a false cover of cast iron lined with clay progress, a glance at them made plain the whole England. at its under side is introduced, being suspended instance, a piece of iron 8ft. or 10ft. long, and of suit- full 1,500, and as population increases, wo see no

of forging. In making a crankshaft, for miles of railway annually constructed will average from above by a strong wire, in order to prevent able diameter, is used as a “ haft” or handle. At reason why railway construction should not increase the access of flame to the interior of the empty one extremity'it is fitted with cross-bars or levers, in about the same ratio. In all human probability, hoppers.. Charcoal and ore are filled in upon the by which it may be turned on its axis ; and the other in the year A.D. 1900, at the present rate of increase, top of this false cover, and, on cutting the wire, end is shaped conveniently for having smaller pieces there will be in operation in the United States, at afterwards form the commencement of the suc- of iron welded to it. The welding end is placed least full 90,000 miles of railway, representing a ceeding charge.

in a furnace, and in about an hour and a-half is raised gross cost, at 40,000 dollars per mile, of 3,600,000,000 When all the oro has disappeared the metallie moved about is fitted with a chain collar or sling, in network of railways will require vast armies of men;

to a welding heat. The crane by which the iron is dollars. To iron, equip, and reconstruct this vast bath is tested as before described in reference to the loop of which the iron rests. The collar works machine shops, iron mills, forges, steel works, will the melting of scrap. If it should be partially in a pulley attached to the chain of the crane, and have to be multiplied, and we trust long before that time solidified, cast iron is added to re-establish com- moves easily, so that the shaft may be readily turned arrives that the labour, mechanical, and manufacturing plete liquefaction ; but if, on the othor hand, the on the anvil. When the proper degree of heat is skill of the country, will be found ample to meet the bath contains an excess of carbon, oxidizing agents attained, the stopping of the furnace is removed, demands, so that we need not be required to depend may be added, as before described, in requisite pro- the steam crane put in motion, and the gigantic bolt upon foreign supply to iron or equip our great portion. From 5 per cent. to 8 per cent of is swung on to the anvil of the steam hammer. national system of highways. spiegeleisen is then added, and the furnace is another furnace, are then brought out and laid on at a very low figure and within the actual experience

We have placed the estimate of annual progress tapped as already described. The quality of the the “face” of the “haft.” A signal from the head of the past two years, and have allowed nothing for steel produced is chiefly dependent upon the quality forgeman, and the hammer drops upon the glowing the presumed increase in the Southern States, of the ore, but considering that ores of great free-mass, and a dazzling shower of sparks fly off in all whenever these shall recover from the effects of the dom from sulphur, phosphorus, or arsenic, can be directions. Again and again the hammer descends, recent conflict. In 1870 the Pacific Railway will be had in large quantities, this process contains all the iron meantime being carefully moved about, so running. and the shores of that ocean will soon be the elements for producing steel of high quality as to have the whole wrought into a homogeneous covered with cities and trade marts rivalling those Having tried a variety of ores, I do not attach mass. Gradually the iron assumes a dull colour, on the Atlantic. At least two more through lines will much importance to their precise composition, so but not before the desired end is obtained. It then be constructed, one on the north and one at the south, long as they are comparatively free from gangue, goes back to the furnace, comes forth glowing, has and these will in time be crossed and interlaced by and from sulphur aud phosphorus, the heat being most difficult part of the work is the formation of The increase of and virtual monopoly of the best

another addition made to its bulk; and so on. The numerous lines on what is now unoccupied territory, sufficient to reduce the most refractory. My ex- the crank-piece, which is forged solid, and forms a portion of the commerce of the East with Europe; perience is, however, as yet limited to experi- huge square projection on one side of the shaft. by the United States, will give our railway movement mental working

When the shaft has acquired the proper dimensions a great impetus, besides incidently fostering and it is allowed to cool, and the haft-piece is cut off developing all the other great business interests of the to be used again. As the shafts are turned down country. The country should be prepared by proper

until a good surface is obtained, an extra inch or so legislation, by the development of its iron mines, THE PARKHEAD FORGE.

is allowed in the forging. The heaviest work on its steel manufactories, its machine shops and skilled

hand at the time of our visit were the shafts for labour, to supply the extended demands that this HE Parkhead Forge, Glasgow, is an extensive two ironclad rams which are being built by Messrs. great increase of railway lines will make. In no and boys, but in consequence of the heavy nature of These shafts were upwards of 14in. in diameter, ordinary business shrewdness and common sagacity, the work, the proportion of boys to men is smaller all shafts are made in lengths of about 20ft., and need there be any fear of failure in the future. A than in other branches of iron manufacture. The these are made with flanged ends so that they may proper fostering on the part of legislation will in buildings cover several acres of ground, and are be firmly united. built in a most substantial style. On approaching

time make this country entirely independent of

For dressing and finishing such huge pieces of foreign manufacture either in iron, steel, or other the entrance to the Forge, the visitor is startled by iron as we have described, special and costly appli- machinery.—“U. S. Railway Times,"

ments

thirty-six of such, exclusive of those of twelve hono- formed into parallels, galleries, mines, and other

rary members, appear on the books of the Soi ety.-works in readiness for the operations, which will Correspondence. I am, Sir, yours, &c., B. HAUGHTON

take place in the course of the ensuing month. President of the Soo ty. THE new navy hospital to be established at

Whittington Club, Arundel-street, Strand, Yokohama, for which provision is made in this OCEAN TELEGRAPHY.

July 14.

year's estimates, will contain about 30 officers and

120 men. By this establishment in the healthier TO THE EDITOR OF THE “MECHANICS' MAGAZINE.'

climate of Japan the costly and unsatisfactory SIR-I am obliged by your notice of the meeting

hospital ships at Hong-Kong and Shanghai will be at the City Terminus Hotel, on Thursday week, on

superseded, and it is also hoped that the present

TO CORRESPONDENTS. the subject of my deep sea telegraph cables, in

necessity for invaliding home officers and men from your paper of the ioth inst. The following remark, of £1 18. 3d. yearly, or 105. 102. half-yearly payable in both impairs the efficiency of the service and en

THE MECHANICS’ MAGAZINE is sent post-free to subscribers the squadron on that station—a proceeding which however, requires a word of explanation. You say, advance. “Captain Rowett comes before the pablic under All literary communications should be addressed to the The total estimated cost of this hospital is £25,000.

tails a heavy annual expenditure-will be removed. great disadvantages, not having a single instance of Editor of the MECHANICS' MAGAZINE. Letters relating to the practical adoption of his system to point to the advertising and publishing departments should be adduring the ten years his patent has run." My dressed to the publisher, Mr. R. Smiles, MECHANICS' MAGAanswer is simple and unmistakable. The two cables ZINE Office, 166, Fleet-street, London, laid by the Atlantic Telegraph Company, with the ments should reach the office not later than 5 o'clock on To insure insertion in the following number, advertise

Kliscellanea. aid of the Anglo-American Company, are my patent Thursday evening. cables. They are described in my specification as We must absolutely decline attending to any communi MR. Cooper, the explorer, has reached the conclearly as words could describe them, and no one cations unaccompanied by the name and address of the fines of Western China, and, according to the last but myself has laid claim to their authorship. In writer, not necessarily for insertion, but as a proof of good advices, was fifteen days' journey from Thibet. all the celebration feasts that followed the successful faith. -ED. M. M. Advertisements are inserted in the MECHANICS' MAGA

THE railway offices of Dairsie Station, on the laying of the cables no reference was made to their Zine at the rate of 6d. per line, or 5d. per line for 13 inser- North British line, were destroyed by fire on the inventor by any of the speakers, which you will tions, or 4d. per line for 26 insertions. Each line consists night of Tuesday week. They were constructed of admit was remarkable, because their success mainly of about 10 words. Woodcuts are charged at the same rate wood. depended upon having the right description of cable. as type. Special arrangements made for large advertise

THE number of visitors to the Patent Office On these occasions the honour and credit were monopolized by the parties who laid the cables and A. 1.-W.M. R.-G. W.1.-R. J.-W.N.-G.E.P.-FR. July 11, was 7,956 ; total number since the opening

RECEIVED.-J. J.-W. C.-J. R.-H. T. R.-E. N. B.- Museum, South Kensington, for the week ending those who brought together the shareholders to pay -B, T. H.-J.G. T.-Messrs. W. G. and Co.-J. E.-K. S. of the museum, free daily (May 12, 1858), 1,329,258. for them. This was perfectly right so far as it went. -T. R.-D. H. R.-T. H.-B. T.-M. S.-T. H. D.-R. J. A SOLDIER of the Royal Horse Artillery was The author of the cable was for the moment ignored. W. W. H.-J. F. H.-D,B.-T. J.-Messrs. F. and C.-J. R. struck by a flash of lightning while walking in The subject was a sore one, and might have marred -R. BJM. H.W.-J.A.-E. M. C.-D. M. L.-H. R. O. Woolwich on Sunday evening. He was rendered the harmony of the meetings. His share of the --W. E. B.-H.R.F. honours would keep, and only remained unsettled the receipt of several books sent for review, notices of NOTICE TO PUBLISHERS.—We have to acknowledge quite blind, and had to be led to the barracks.

ADVICES from St. Etienne announce that a great because the distinction must be accompanied with which have been kept out by press of other matter, but fire has destroyed the velvet-ribbon manufactory sume substantial compensation in the form of a which will shortly appear.

belonging to MM. Descours and Co., at St. Paul-enpatent right, for, happily, well-observed laws protect

Cornillon. The loss is estimated at 500,000 francs, inventors of instruments which contribute to the

besides 300 hands being thrown out of employment. public good, and a deep-sea cable which had been

A LARGE diamond, found by a Griqua near the for years pressed upon the attention of the Atlantic

Vaal River, has been forwarded to the Colonial Telegraph Company must not be an exception to so Nabal, Itlilitary, and Gunnery Stems. Ofice at the Cape. It weighs 15; carats, and is good a legislative provision.

valued at about £400, Several others have been From the year 1857 I had been urging the Atlantic

found in the vicinity of the Vaal River. Company to adopt my light hempen cable, which The American transport ship “Guard " has THE “Moniteur” publishes a list of medals would lie at the bottom of the sea as still as the arrived at Civita Vecchia to embark a quantity of conferred at the instance of the Minister of the Inteheaviest iron cable could lie, and could be safely statues and works of art purchased by Admiral rior :-Two gold of the 1st class, three of the 2nd, laid at half the cost of the cables they have chosen. Farragut for various museums in the United States. four silver ist, and 97 silver second, for acts of But instead of making the pure and simple hempen ACCORDING to a return just published, it appears devotedness connected with the saving of life during cable-which, for every scientific reason, is indisput- that the unclaimed wages of deceased seamen, paid the months of March and April. ably the best-in despite of both science and com- into the Consolidated Fund during the year 1867, FIFTY house-sparrows have been received from mon sen se, they made their first cable envelope en- amounted to £7,783 6s. The fines and forfeitures Britain by Mr. W. Rhodes, of Quebec, who has tirely of iron, their second cable a mixture of iron for desertion, &c., amounted to £349 11s. 7d. turned them loose in the Governor's garden, below and hemp loaded with tar, their third cable of The Italian Chamber of Deputies have just passed the Wolfo and Montcalm monuments. Mr. Rhodes hemp and iron wire without the tar. In the last a vote of 3,000,000 lire for the armament of the iron- is of opinion that this bird may be acclimatized so two cables Manilla hemp was used, and so the specific clad fleet and the conversion of the marine rifles as to remain during the whole year. gravity of their cable was reduced precisely as my into breech-loaders. During the debate the Minister A FINE fresco has just been discovered in the patent provides. The two last cables are carefully of Marine stated that the Italian ironclad fleet was church of Santa Maria del Giardino, which is now specified in my patent of 1858, in anticipation of in perfect order, and left nothing to be desired. being demolished. This fresco, which is in a good the probability of the Atlantic Company making step The Government had determined to arm the fleet state of preservation, represents St. Antonio of by step from iron wire envelopes to first a mixture with Armstrong guns.

Padua, and is attributed to the painter Suardi. and then to lighter and lighter cables.

When the French military medal of the Legion of At the meeting of members and associates of the The two last cables have a single iron wire Honour is given to privates or non-commissioned Royal Academy on the 30th ult., for the election of wrapped in several strands of Manilla hemp. Com- officers a pension of 100f. is attached to it, but there a member in the place of Baron Marochetti, depared with the first cable, which is iron, this is, is no pension when it is given to general officers. ceased, Mr. F. Leighton was chosen by a largo of course, light. But of what use can be the iron There are also establishments attached to the Order majority. Mr. Leighton was elected A.R.A. in July, wire? They admit its own weight in three miles' of the Legion of Honour for the education of the 1864. depth destroys itself, and they admit that oxidation daughters, nieces, and sisters of the members. The The authorities of the South Kensington Museum would destroy the hemp with which it is surrounded principal or central one is fixed in the large buildings are forming a collection of engraved portraits, and a The pure and simple hemp envelope is, therefore, the of the famous Abbey of St. Denis, confiscated at the considerable number of those which have already best, and the cables that are laid and doing good Revolution. It was founded by Napoleon in the been obtained are now on view on the upper floor of service are indisputably my patent cables, and all Chateau of Ecouen, and was placed under the super- the National Portrait Exhibition at Kensington. that I need say is that they are not the best is amply intendence of Madame Campan.

Some miscreant recently conveyed a quantity of proved. But if any merit can be found in placing HER MAJESTY'S yacht "Victoria and Albert," poisoning matter into the park of the Bishop of a wire in the centre of each strand I am willing to Captain His Serene Highness the Prince of Leiningen, Durham at Auckland Castle, and put it into the meet the wishes of any party; though it was included recently returned to Portsmouth from a cruise beyond River Gaunless, which runs through the park, for in my patent to protect my invention from piracy, the Arctic circle, the purpose of which still remains the apparent purpose of poisoning the fish with I do not recommend it. Your numerous readers will one of the official mysteries. This magnificent vessel which the river abounds, and in which diabolical act, be glad to see by what I have stated that there are is, we believe, the first of her size and costliness we regret to say, he partially succeeded. hopes of having my light, inexpensive, and efficient which has made the attempt to penetrate the dan SEVERAL Italian journals state that Father Secchi, cables laid, that the cost of messages over long deep- gerous fiords and intricate channels of the Nor- the constructor of the great astronomical clock so sea lines may be as cheap as those on land. To this wegian coast. The ship left Portsmouth on the 1st much remarked at the Universal Exhibition of 1867, end we must hope the press will give a helping hand. June. It is surmised that the trip was undertaken has discovered a motive power, lighter, stronger, I trust this explanation will be allowed a space in as a trial cruise, with the view of its being repeated and more economical than steam. They add that your next number.--I am, Sir, yours, &c.,

on some future occasion for the benefit or pleasure the learned Italian is stated to have laid his invenLondon, July 11. W. ROWETT. of the royal family.

tion before the court of Portugal, which is disposed [With regard to the broad question with which A PARLIAMENTARY paper issued on Saturday to purchase it. Captain Rowett's letter opens, we can only say that gives an account of the army prize money paid to the A CERTAIN doctor lately stated for the information we were present at the meeting, and put the plain Commissioners of Chelsea Hospital from Jan. 18, of the Board of Education at the Normal State Uniquestion * Can you point to any examples of the 1809, to Dec. 31, 1867, as follows:- To 5 per cent. versity of Illinois that the atmosphere was composed practical application of this system?” receiving a deducted from prize money, £2,325 Cs. 11d. ; to cash of oxygen and hydrogen. Ho accounted for the plain answer in the word “ No.” The chairman arising from shares of prize money awarded to the explosion that takes place, consequent to a discharge also referred to the same fact as being a misfortune army, £1,508,822 3s. 6d. ; to cash arising from di- of electricity, on the ground that, as he believed, for Capt. Rowett, which the captain tacitly admitted. vidends, &c., £260,769 185.6d.; total, £1,771,917 9s. 22. the electricity decomposed the air, leaving the -En. M. M.]

By cash refunded, £993,317 19s. 4d. ; by expenses in hydrogen as an explosive compound behind !

executing acts, £64,876 108. 10d. ; by sums paid to A NOVEL race was run last week between a horse CIVIL AND MECHANICAL ENGINEERS' Royal Hospital and transferred to the Exchequer, and car and a velocipede. M. Carrere in a one-horse

£638,439 8s. 9d. ; by sums paid to the Commis- car, and M. Carcanade in a velocipede, started from SOCIETY.

sioners for Works and Buildings, £40,000; balance, Castres at twelve, and the victory was to be decided SIR.-In reference to your notice of the annual £35,283 10s. 3d. ; total, £1,771,917 98. 2d.' In addi- in favour of the person who first arrived in Toulouse. meeting of the above Society, given in your paper of tion to the balance here stated there is in the Bank | The race was a very keen one, M. Carrere baving the 4th inst., you state that this Society has been of England £31,225 14s. 1d. to the credit of the army arrived in ļoulouse at 6, and M. Carcanade at 6.25. established for the mutual benefit of assistant en- prize account, and in the funds £65,000 Three per It is stated that petroleum oil possesses the highest gineers and pupils in both civil and mechanical en-Cent. Consols.

efficacy as a destroyer of all kinds of insects injurious gineering. Permit me to say, that in addition to PREPARATIONS are being made at Chatham for to plants or animals, and the less purified, and, conthese classes of the profession, the Society is largely carrying out some siege operations on a scale of sequently, the cheaper it is, the better. Thirty patronized by men who practise engineering on their magnitude never previously attempted. The whole parts should be mixed with 1,000 of water, and apown account, and that at present the names of of the lower portion of Chatham lines has been I plied where required. The "Medical Times” states

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