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8. The impossibility of burning any part of the boiler or generators by the most in
LIVERPOOL AND MANCHESTER RAILWAY. ||tives, of which he speaks in high terms. He || deposit will of itself collect in a place proThe eighth half yearly meeting of the claims for it no less than 13 advantages vided for it, and be blown off at will. shareholders of the Liverpool and Man-over his previous boiler. We will publish, the evaporating point. 7. The generators always being kept at chester Railway Company was held on in our next, his description, or so much of Wednesday, the 27th of January, in the Cotton Sale-room, at the Exchange, Liver-it as we find in the London Mechanics' pool; Charles Lawrence, Esq., in the chair. Magazine. The Report of the Directors for the last MR. PERKINS' CIRCULATING STEAM-BOILER. in the least affected by expansion and consix months, which was submitted to the meeting, was highly satisfactory to the shareholders, showing a considerable increase of receipts, and in some important points showing a positive, and in most a comparative, reuction of expenditure. The receipts appear to have been-in the Coaching department...........167,897 19 2 Merchandise department.......46,375 15 8 Coal department.............. 3,682 8 8
10. The perfect and simple method of separating the steam from the water and foreign matter.
11. The getting up of the steam in less than half the time now required.
12. The simplicity of the construction of the boiler, and the ready method of re
The above facts can be demonstrated
not only theoretically but practically. An operating model of this boiler may be seen daily at present at the National Gallery of Practical Science.
Explanation of the first-mentioned Advantage.
9. The boiler and generators not being In 1832, Mr. Perkins took out a patent traction, owing to the peculiar arrangement for a new steam-boiler on the circulating of the tubes or generators. principle, which was more than once noticed in our Journal for that and the following year, and the advantages which it offered freely allowed; while, at the same time, its originality was as freely questioned-that is to say, Mr. Perkins was alleged to have but resuscitated, or rather re-invented (no doubt very unconsciously), a mode of con-pair. 7117,956 3 6 struction first promulgated two or three 13. The absence of all destructibility by The increase in the merchandise department years before in the pages of the Mechanics' burning, in consequence of using anthriis the more gratifying, inasmuch as it has Magazine. Mr. Perkins has now pro- cite coal,-although the fire be urged to its taken place in the face of a considerable duced what he calls "a new modification" greatest intensity. reduction in the rates of freight made by of this circulating steam-boiler; and in the the Mersey and Irwell Navigation Compa- first number (just published) of the Magany, whilst the rates of carriage by the rail-zine of Popular Science, edited at the Adeway remain unaltered. The total laide Gallery (which owns, we believe, Mr. (including 3,4091. 16s. paid for goods de- Perkins for its originator, if not founder), stroyed by fire) amount to 71,9957. 13s. 4d., there is a very elaborate exposition of its leaving a nett profit of 45,960l. 10s. 2d. merits from the pen of Mr. Perkins himOut of which the Directors recommend that self. We are far from subscribing to all a dividend should be made of 5l. per share Mr. Perkins says in favor of his new boiler, for the half year; and that 6000l. should even as thus modified, for notwithstanding be appropriated to the purchase of heavier he assures us that his statements can be rails, leaving a balance of 1,5691. to be demonstrated "not only theoretically but carried to the credit of next half year's practically," there are some of them which account. The cost of locomotive power, it would be difficult to reconcile with any which has been for some time the heaviest received theory; and we cannot forget that and most formidable item in the expenditure this very boiler has been tried on the Liverof the Company, appears to be undergoing pool and Manchester Railway, but not adopta gradual diminution. For the last half ed; though Mr. Perkins, in his present esyear it amounted (including the cost of three say, takes no notice whatever of that trial new engines) to 15,6811. 178. 9d., being or of its results! But mixed up with Mr. about 8001. less than during the preceding Perkins' rather extravagant laudation of his half year. This is a very satisfactory re-invention we find so many valuable practical duction, when it is recollected that there has hints and so much ingenious and suggestive been a large increase of business, the re- speculation, that we must place the whole of ceipts of the last half year having ex- his paper, with but little abridgement, beceeded those of the half year preceding by fore our readers. Of the new periodical in upwards of 18,000l. In the maintenance which it appears, we must not omit the opof way there is an increase of about 1,500l.; portunity of saying that the projection of it and it does not appear probable that does great credit to the Institution from considerable reduction will be made in this which it emanates; and that though in this branch of expenditure until the line its first number it has rather too much of a rally shall have been laid with heavier rails. horn-book character, there is nothing either The Report stated that the works con- in its plan or in the talent displayed in it, nected with the tunnel under the town of to forbid our entertaining strong hopes of its Liverpool, and the new entrance in the Old proving a most useful auxiliary in the cause Haymarket, were advancing towards comof practical science. We cordially wish it pletion, and would be finished by the end of every success.~[ED. M. M.] the month of May. It was stated, in reply Extracts from Mr. Perkins' Paper. to the inquiry of a proprietor, that the propriety of forming a new station for passenThe following are the advantages which gers at Manchester was under considera- result from a new modification of the circution, and that, if formed, it would be cov-lating steam patent, granted to me in 1832: ered by a roof, as at Liverpool, to protect the passengers from the weather. The Report, which appeared to give general satisfaction, having been agreed to, and a dividend of 5 per cent. on the last half year having been declared, the meeting broke up.-[Manchester paper,]
Our countryman, Mr. Perkins, has brought out a new steam-boiler for locomo
1. Absolute removal of all the danger arising from explosion.
2. Great economy in fuel.
3. Much reduction of boiler-room, as well as of weight.
4. Not one third of the water in the boiler now used, being necessary.
The great drawback upon the important invention of steam navigation has been the disastrous effects caused by the explosion of steam-boilers. The great importance of a perfect remedy will readily be admitted! The many experiments which I have made within the last ten years, go to prove that if the steam be generated in tubular boilers, no danger can result from explosion; but there are many almost insurmountable objections to tubular boilers as hitherto constructed, particularly for steam-navigation. The boiler which is now about to be described, possesses apparently all the properties which have hitherto been sought af ter. To show the reason why this boiler is free from explosions, the causes (of which there are at least three) must be described.
This first and most common cause is from the pressure of common steam. What is meant by common or pure steam, is such as has not been sudeenly elevated, or such as has not been compounded with an explosive mixture, by the improper management of the boiler.
The first kind of explosion is quite harmless, as the boiler simply rends or gives way in the weakest place, which is caused from wear, or some defective spot. The second, which I some years since accidentally discovered and published, (and which has since been experimentally proved to be correct, by the celebrated French philosopher, M. Arago,) arises from the water getting too low in the boiler. The fire then impinging on that part of the boiler which is above the water, causes the heat to be taken up by the steam, which rises by its superior levity to the top of the boiler, causing it sometimes to become red-hot, and so elevating the steam to a much higher tempera
5. There being no possibility of any de-ture than its pressure would indicate. Now, posit of foreign matter in the generators.
8. No furring up of the boiler, as all the
when the boiler is in this state, and the safe. ty-valve suddenly raised, the water will be re,
For marine and locomotive purposes, it has been found that brick-work must be dispensed with, on account of its weight and bulk; of course, the fire must be made within the body of the boiler. Now, it so happens, that this new modification of the tubular boiler is extremely well calculated for an internal fire-place; for we have only to extend the outward row of tubes down to the firebars, and we have the most convenient and economical fire-box.
Second Advantage.-Although it is not yet accurately ascertained what the sav ing of the fuel is, yet, from repeated experiments, I have no doubt that it will amount to one third of the fuel now used by the best marine boilers.
Third Advantage.-The reduction of boiler room is owing to the greatly increased evaporating surface in the boiler, which allows much reduction in size, and for the same reason in weight.
lieved from the steam pressure, and rush up || method of generating steam, and which I|| gets empty or dry, were it not that in the amongst the surcharged steam which thus re- will now attempt to describe. centre of the sealing-plug is affixed a fusiceives its proper dose of water; at the same This new boiler is made up of generating ble metallic plug, which is rivited into it, and time, that part of the boiler which has been tubes and the common flat-bottom wagon- will melt before the steam is sufficiently raised in temperature, giving off its heat to boiler; from this flat-bottom a series of tubes powerful to burst the tube. the water so elevated, steam is generated hang perpendicularly over, and in, the fire, in an instant, of such force as no boiler can from one to two feet in length, according to resist. This kind of explosion has of late the size of the boiler, and from two to three years been very frequent and disastrous, inches in diameter. On the upper side of particularly in America. this flat-bottom is a continuation of these The third and less frequent kind, al- tubes projecting the same distance into the though most terrific, is undoubtedly caused water in the boiler. In the interior of the by an explosive mixture having been formed tubes which hang in the fire, is fixed a thin in the boiler. It has long been known that tube, wo inches in diameter; when the tube hydrogen has been often liberated, by the is 3 inches, internal diameter; open at the boiler being overheated by improper sto- top and bottom, and ten inches in length, king, as well as not being properly sup- this tube stands upon three legs, each one plied with water; but simple hydrogen can- inch long, and the water stands level with not explode, and where it could get its at- the top of it. These generating-tubes are mospheric air, which is absolutely necessa- hermetically-sealed, so that the steam which ry to form the explosive mixture, it has been is formed in the interior of the upper half difficult to understand. We have only, how-of the tube cannot possibly escape. ever, to look at an air-drawing feed-pump, The important effect of circulation is and the source will be readily seen, It is more apparent in this modification of the frequently the case that the feed-pump boiler than in any other which I have tried. draws air as well as water, arising from its The upper, or evaporating part of the herunsoundness, &c. The more air the pumpt mitically-sealed tube, contains steam of a draws, the less water is forced into the boil-temperature of about 80° above the boiling er; of course, the boiler is more and more point, when the steam is generating at atexposed to the fire, and the heated parts of mospheric pressure; but when generating the boiler become oxydised, and rapidly at a higher pressure, the evaporating point liberate hydrogen; and as sufficient air has increases in a geometrical ratio. This part been pumped into the boiler to form the of the tube, which is surrounded with water, mixture, it will be ignited by an overheated is incased in a very thin tube, open at top part of the boiler, and the tremendous effect and bottom, which causes a very rapid circan only be equalled by an explosion of gun-culation, and sweeps off the heat so effectupowder. ally, as to be certain of keeping the steam The construction of this boiler may now in the upper part of the tube, at the evapobe described; but the practical objections rating point. Experience shows that, after to the tubular, the compound tubular, and the steam begins to form, not only the fire the common boiler must also be described, part of the tube, but the evaporating part of so that the remedy to these practical defects it, which is in the boiler, receives no more may be better understood. The two great- addition to its temperature, not even one est practical objections to the tubular boiler degree-which proves the great importance are its furring up and burning out. After of rapid circulation. great expense and time, I came to the conIt is well known that water is a worse clusion that until these two practical difficonductor of heat (particularly downwards) culties could be removed, they would be fa- than any other matter; but at the same tal to the economical generation of steam for time, the property which water has of carryany other purpose than that of steam-gunne-ing heat upwards, is greater than any other ry. I have, however, at last been so fortunate as to hit upon a modification which has completely removed all objection to this
This theory has not, to my knowledge, been published; and until recently, I did not see how the atmospheric air could find its way into the boiler, which is so essentially necessary to form the explosive mix
Fourth Advantage.-In consequence of the interior of the boiler being filled with evaporating tubes, which displace a large portion of the water, as well as the rc. duced size of the boiler itself, it is not too much to say, that one third of the water commonly used will be sufficient.
there being no possible escape from the Fifth Advantage.-In consequence of hermetically-sealed tubes, there cannot be any deposit, as the same water in the generator may be worked over and over again, ad infinitum.
Seventh Advantage.-The generator cannot get above the evaporating* point,
Sixth Advantage.-The furring up of the common boiler is occasioned by the slug. and the extra heat at the bottom of it. gish circulation of the water in the boiler, But forced circulation not only takes up the extra heat, but keeps all the foreign matter in motion, and as there is a much the boiler than at the other, all the mat. more rapid circulation at the fire-end of ter that would otherwise deposit and be matter. Now, this law of the upward-car-come fixed, finds its way to the other end, rying power of water is taken advantage of, and can be drawn off by a stop.cock and by filling the tube about one third full at pleasure, as it will never incrust. of water, the steam which is generated is given off at the top of the internal tube, and will constantly keep the evaporating chamber filled with steam, of a temperature in proportion to the density of the steam in the boiler. The effect of the most intense heat serves only to generate steam the faster, without raising the temperature of any part of the boiler, generating-tubes, or steam; Having had about twelve years' practice in gene- while without circulation, the boiler would, rating high steam, from 1,500 pounds to the inch down as is often the case, get red-hot, and genewards, and having established the fact, that nɔ dangerous result has occurred, although a great number rate less steam, by driving off the water of explosions have happened; and having at length from contact with it, and materially injure removed all practical difficulties, I feel warranted in undertaking to guarantee to the public a system of the boiler. So long as there is enough wagenerating steam of any required power, not only ter in the bottom of the boiler, to be above with increased economy, but with perfect safety. the bottom of the circulating-tube, say two 1 If the feed-pump is surrounded with water, as is inevitably the case with condensing-engines (and only inches, no derangement of the tube can take such are used in this country for steam-navigation, place, as the steam and water will, although atmospheric air cannot get into the boiler. Upon in it is obliged to rise 12 inches, sweep off the quiry, I find that nearly all the feed-pumps used in America, are worked without having water outside heat from the evaporating-tube, which will the pump. This undoubtedly is one of the reasons
This kind of explosion cannot take place in the new boiler, since no hydrogen is formed in it; for no part of the boiler is exposed to the fire but the bottom, which is certain to be kept at a temperature quite as low as the water in the boiler, which surrounds the generators, by the dashing down of the water outside of the circulating tubes.
*To prove the best temperature to generate steam, prepared an iron cup, of massive thickness, cast for whilst it was allowed to cool gradually, several mea the purpose; it was heated to a white heat, and, sures of water were placed in it, one at a time, each in succession, as soon as the previous one had evapoThe 1st measure in evaporating occupied 90 seconds. rated to dryness.
The vapor, or steam, thrown off, began now to appear, and became more distinctly visible with the evaporation of succeeding measures of water
4th measure in evaporating occupied 30 seconds.
7th measure showed what I had termed the evaporating point, and in a dense cloud of steam, evaporated suddenly in 6 seconds.
8th measure occupied a longer period, viz. 10 seconds.
why there has been so many more accidents in Amo-prevent an explosion of the tube, and which in the iron cup at a white heat, was perceptibly not would inevitably take place, when the boiler
pics than in England,
since the extra heat is for a certainty swept off by the rapid circulation.
From the London Mechanics' Magazine. ENGLISH AND AMERICAN STEAMERSAVERY'S ROTARY ENGINE. Sir, I should feel obliged for further information, through the medium of your Magazine, from some of your many American readers, relative to Avery's recoil engine, and also a New-York steamer, mentioned in the Encyclopædia Metropolitana, the De Witt Clinton.
bottom plate, after having been perfora.which is called in Wales, stone-coal, may ted with proper-sized holes, female cou- be obtained there in any quantity, and is Eighth Advantage.-Experience shows pling screws are firmly rived into it; the undoubtedly the most economical where it that wherever circulation is active, no heat lower half of the tubes, which has been can be used, as is the case in this boiler. can get above the evaporating point, let reduced one third in size, about two inches the heat be ever so strong." * This boiler from their ends, is formed into a male is so constructed that no part of it is ex-screw, to fit the female coupling-screw. posed to strong heat, where strong circu-This male screw is faced perfectly flat, lation is not at the same time going on; and the shoulder is made to be screwed consequently no over-heating can by any firmly in contact with the bottom of the means take place. It is a fact, that no boiler. The upper half is screwed in the extra heat can get into the steam, since same manner. The face of this screw no heat is suffered to pass into the boiler is rounded, so that when it is brought in above the water, let it get ever so low. contact with the flat surface of the lower half, it may be the more certain to make a perfect joint. The upper half is not allowed to touch any part but the flat sur- The cylinder of the De Witt Clinton is 63 face of the lower half of the tube. The inches diameter; 10 feet double strokes ; plug-nut, which is used for hermetically. revolutions 26 per minute; effective pressealing up the tube, is perforated in the sure, 12 lbs. per square inch on the piston centre with a small hole,-say one eighth-323 real H. P. Is it not a mistake to of an inch in diameter, and filled with a call it 646 H. P., as nothing is said of two fusible metal, which will be driven out be-engines, and one is more powerful than fore the tube will rend, and which could any at work in England at present. The only take place should the water be al-Radamanthus is 220 nominal H. P.; has lowed to escape from the boiler. two engines; 55 inch cylinders; 10 feet double stroke, 20 per minute going together with low steam; say effective pressure 10 lbs. per square inch on piston-about 290 The De Witt Clinton draws real H. P.
Ninth Advantage.-The tubes of the locomotive tubular boilers now in general use, are riveted at each end; and as no provision is made for guarding against expansion and contraction, the wear and tear is enormous. The tubes, however, in this boiler are connected in the middle, and each half is allowed to contract and expand without impediment.
Tenth Advantage-To separate the steam from the water and foreign matter, a small steam-chamber is attached to the top of the furnace-end of the boiler. A pipe somewhat larger than the steam-pipe passes from the top of the boiler to the bottom of this steam-chamber. Directly over this pipe, a dome is fixed, about three quarters the diameter of this chamber; the depth of
this dome is rather more than half a
The wagon-boiler is considered the weak. est form, but this new boiler is altered somewhat in shap; the bottom is perfectly flat instead of concave; the sides are also flat; the top is semicircular. The female only 4 feet 6 inches water, and ought to be coupling-screws undoubtedly materially impelled by one such engine faster than any strengthen the flat bottom. The boiler is sea-going boat in Europe, at least before sphere, and within two inches of the top to have tie-bolts from the top, the number the wind. Four valves are mentioned 17 of the pipe. From the bottom of the of which is to be determined by the strength inches in diameter; the number required chamber there is also fixed a return-pipe of the steam to be generated in the boiler; for a double-acting engine. How are these half the size of the steam-pipe, leads down to within two inches of the they pass down vertically between the managed with 20 lbs. steam per square inch tubes, and are screwed into the flat bottom on the safety valve? That the thing is bottom of the boiler. The operation is of the boiler. Tie-bolts are to be used also well managed in America I doubt not; the thus: When the steam rushes into the to hold the flat sides of the boiler from bulg-load must be near three tons on each of the chamber, it takes with it more or less waing out when used for high steam. None steam valves, unless they are balanced as ter and foreign matter (this is what is of the nuts of the tie-bolts are exposed to in Watt's plan, or made like Hornblower's technically called priming,) which strikes the fire, consequently no objection can arise double-seated valves, such as are used in the concavity of the dome, and throws from that source. This boiler may be Cornwall; or Tredgold's packed cylinder down the water and foreign matter to the made much stronger than any other, on ac-modification; or according to some other bottom of the chamber, while the steam count of its diminished size; setting aside similar plan. The expression, “steam 20 in a pure state passes off through the the absence of any danger from the second lbs. per square inch on the safety valve, steam-pipe, and the foul water returns to and third cause of explosion, which has expanded inch cylinder, 10 lbs. average," the bottom of the boiler through the re-been described, the ends of this boiler, which I presume means steam 20 lbs. per square turn-pipe. inch on the safety valve expanded in the cylinder to 10 lbs. average. The engine apparently works expansive-how much is the question? Do the Americans usually follow their Consul's example, as given in the Edinburgh Review, and divide the lbs. per square inch on the safety valve for expansion? In this case, I shall assume 30 lbs. pressure on the piston per square inch; expanded, perhaps, to 22 lbs.; rather high for condensing.
are flat, may be made sufficiently strong by Eleventh Advantage.-The steam is got ribs. In fact, this boiler must be proup much quicker than in any other boiler, nounced a perfectly safe one, since only the in consequence of the great evaporating first kind of explosion can take place, which surface within it, an the diminished quan-is absolutely harmless; the first kind has tity of water in the boiler.
Twelfth Advantage-The construction of this boiler is extremely simple, the distance from it in a state of buoyancy, and there moved freely in every direction. So circumstanced, the water evaporated slowly; but when, by the evaporation of successive measures, and the lapse of time, the
iron was cooled down to the "evaporating point," the water then evidently came in contact with the iron, and the augmented rate of evaporation was as 90 to 6, or as 15 to 1, the rate being increased or multiplied 15 times; or, in other words, a given quantity of water was converted into steam, 15 times quicker at a moderately low, than at an intensely high heat.
* It is a curious fact, that there are now many boilers which have been in constant use for more than
fifty years-the cause is, that these boilers are suffi
also been described. The ease with which
are fac-similies of each other.
Thirteenth Advantage.-All persons who have been in the habit of using anthracite coal, know that the intensity of its heat is so great, that if urged to its greatest power, the best fire-brick is readily fused. It is on this account that it is so difficult to be used ciently large to make all the steam required, without for raising steam; still, some careful stokers being forced; this is done with a great sacrifice of have used it to great advantage. It is, fuel but since it became necessary to economise fuel, the boiler has been very much reduced in size and al bowever, done at a great sacrifice of heat, tered in form, exposing many parts to be overheated-for slow combustion and thin firing only It is true, such boilers raise much more steam with the same fuel, and undoubtedly much more is saved in fuck than is lost in wear and tear of the boiler. This is noticed, to show the great advantage of so constructing the boiler that the heat will always be kept down:
To produce the greatest effect, rapid combustion with a deep fire is necessary. In the new boiler, the heat cannot possibly be too great. This coal,
Or, is the steam cut off at one third? If sc, this would give 10 lbs. per square inch pressure, or 4 lbs. below atmosphere, at the end of the stroke, or an expansion of three times, and an efficiency of gross power of about 183 lbs. per square inch on the piston. But this would scarcely produce 12 lbs. ditto effective pressure; while the first plan gives rather too much. A corrected statement would oblige, and is requested.
The following estimate was made on the first appearance of the account of Avery's engine, for a gentleman who had some idea of erecting one to work a small circular saw, to cross cut borrel-staves, &c. All
Mines, Cornwall, Feb. 16, 1836.
VISIT TO THE QUICKSILVER MINES
the difficulties of the quantity of fluids issu-||ried, when acting against an uniform resist-ing, and on waking, found him waiting for ing from a given aperture, at a given pres-ance. At the building alluded to, which is sure, are avoided; as the estimate is foundon one side of the village, and covers the ed on the possible effective power which entrance to the mines, we changed our can be produced by the fuel used. Both dresses, ane the keeper unlocking an iron the weight of the fuel, one half of wood, gate, we found ourselves in a horizontal galand the time of consumption, must be aslery three or four hundred yards in length, sumed in consequence of the defective acrunning directly into the hill, at the foot of count. In mining engines, 24 hours is a which the edifice is created. Here we day; in manufactories, sometimes only 12 came to a small chapel with a light burning hours, which I assume; and, taking half a You know I travelled through Germany before the picture of the virgin, and turning load as half a ton is 1,120 lbs., and oak to as a pedestrian-a mode of travelling which short to the left commenced the descent. coal being (see Engineers' Pocket-Book) I would recommend to others through that It has nothing difficult, being effected the as 1,089 lbs., to 1,120 lbs., the fuel is equal interesting country.* You must imagine whole way by means of stairs in pretty good to 618 lbs. of coal, and 7 lbs. of water me then on the second day of my journey, order: indeed, the mines have nothing cor evaporated per lb. = 4,826 lbs.; say 70 from Trieste to Vienna, in a region thickly responding to the ideas of terror which we cubic feet of water. The steam in lbs. per settled and well cultivated, and with a mix-are apt to connect with such places, except square inch, on safety valves, is 80 lbs. at- ture of hill and dale sufficient to make it the atmosphere, which throughout the mine, mosphere 94 lbs. pressure; to 23,500 highly picturesque. An old countryman must be strongly impregnated. with merculbs. do, on the square foot, + 310, about with whom I stopped to converse about rial vapor, and is constantly producing salithe volume of steam due to one of water noon, informed me that by taking a cross-vation among the workmen. Having de(see Tredgold) at 6 atmosphere, then we cut over the country, I should make my road scended by seven hundred and twenty-seven have 4,185,000 lbs. +70282,950,000 to Idria much shorter than by following the steps, reaching to a depth of one hundred lbs., one foot high efficieney for 12 hours highway, and as I am fond of by-ways I and twenty-five fathoms, we arrived at the 39,300, 1 atmosphere wasted received his information with pleasure, and region where chiefly the cinnabar is pro32,750 lbs. 1 foot high per miuute. Taking soon after struck into a wagon track, to cured. The mining operations are carried however two fifths of this for effective pow-point out which to me, he kindly left his on principally in galleries, the friable nature er for 12 hours, for half a load of oak wood, work. The wagon track, after leading me of the ground or rock seldom admitting of It appears from Dr. Davies Gilbert's inves- through some retired villages, dwindled into larger chambers. The cinnabar is in strata tigation, that the effective power can, in a foot-path, and even this soon after disap- of from two to six inches in thickness, and no case exceed half the efficiency; and peared and left me alone among the hills: of a variety of colors from dark to light red, that, for this, the velocity of the motion of but a lover of nature is never solitary, and the quicksilver sometimes being mixed with the aperture, at the end of the arm, must particularly with such varied and beautiful it, sometimes occurring in the intervening be three fourths of that due to the steam pres-scenery as almost every step opened to view. strata of earth or stone. Sometimes the sure, or a velocity about equal to a common I am strongly tempted to describe some cinnabar is of a brilliant red, and once I shot. The velocity of 37,660 feet per min- parts of it, and also the simple and hospit- found it in small crystals, but such speciute is not half that which is most effective; able manners of the people-but this would mens are rare generally it is of a dull red though it must be admitted that four hun- not be exactly suited to a Journal of Sci- color, and the stone is so brittle that nothing dred and twenty miles per heur is conside-ence. The country towards evening, be- more than a pick-axe is required. rably fast. The American engine seems came a constant succession of steep rounded strata affording the quicksilver appeared to just within the limits of possibility, since eminences, generally of considerable height, have no particular direction, and occupy the power is five times that assumed by and just before sunset, reaching the sum-about one third or one half of the entire Mr. D. Gilbert, and the velocity so much mit of one of highest, I had just under my mass of rock. Proceeding a short distance, less, that iron arms may be just enabled to feet the pretty little town of Idria. It is however, we came to galleries where the withstand the centrifugal force. More facts situated at the bottom of a deep valley or cinnabar is less common and the quicksilver of work performed are requested. The green, the houses were white, and as the is the chief object of search. It occurs principle of recoil is the first known applica- streets have to follow the windings of the here sometimes imbedded in a friable rock, tion of steam power, though for useless green ravines, it has a simple and very sometimes in a kind of earth, in appearance purposes; but the execution of duty will pleasing appearance. Near the center, is and hardness resembling talcose slate, but reflect credit on American ingenuity; the a conical hill with a church on its summit principally in the former. Generally, it is more so from the well-known and frequent from which a line of a dozen little chapels, in particles too minute for the naked eye, failure of similar attempts in Europe. The along the side of the eminence, showed the but often when the rock is broken, small advantages of expansion, however, must be course of the Via dolorosa-sometimes an globules present themselves, varying from abandoned, even if Avery's engine should appendage to papal churches. A stream a size just large enough to be seen, up to chance to rival the common high pressure of water about forty yards in width, dashing that of a common pin's head. These gloengine, not worked expansively. along the bottom of the valley, and several bules are not distributed at random through How to observe requires an observation, of the excellent German roads, running zig- the mass, but the substance in which they and deserves more. The distinction be. zag up the steep ascents completed the occur forms strata usually about one inch tween steam pressure and steam in lbs. per view. At the entrance of the village my or two in thickness. square inch, on the safety valve, should be passports were examined, and the officer Descending still lower, we soon came to attended to (the gross pressure in the cylin. having ascertained that I wished to examine the richest part of the mine. Here the der, as well as the effective ascertained is the mines said he would send a person to gangue consits almost entirely of the talcose known). This is equally required for high accompany me. Accordingly, a sergeant earth mentioned above, and the globules are pressure engines, since the wasted atmos. soon after called at the public house where so large that when it is broken, they fall out phere is one-third of the efficiency or gross I lodged, to say that the mining operations and roll to the bottom of the gallery. power of steam of 30 lbs. per square inch were carried on day and night, and that laborers here are relieved every four hours, on the safety valve, and one fifth of steam could enter at any time: I had noticed from being unable, from the state of the atmosof 60 lbs. ditto; and, in all cases, if worked the hills a dark crowd of men in front of a phere, to work longer than this at one time. expansively, it should be stated at what part large building, and those he told me, were In the other parts of the mine they work of the stroke the steam valve is closed. the evening gang about commencing the eight hours. There are three hundred and Believing that many American steamboat descent. I appointed 6 o'clock in the morn-sixty altogether employed in the mines, diengines, (from various hints, however, rather than statements) are worked expansively, I am desirous of information as to what extent expansion is there in practice car
*We most heartily second the writer's recommendation. For health and information no mode of travel ling is equal to it, and what is of more importance to some, it is fashionable in Europe just now."
vided into three companies, and working, each, eight hours out of the twenty four; their pay is only from 15 to 16 kreutzers (12 to 13 cents) per day, the usual pay of
day-laborers throughout Germany. I found || is kept in operation only during the winter that such a term involves no exaggeration, several of them suffering from the effects months, and then the vapor which escapes and indicates no peculiar professional or of the mercury. from it is a serious annoyance to the town: personal enthusiasm. It is even gratifying Having loaded myself and the guide with they have a blast three times every fortnight. to find, that such men, occupied exclusively specimens, I returned by the same way to The price of quicksilver at the mines is with a subject, which has been regarded the upper mine and proceeded next to exa- 112 florins for one hundred German pounds, as too inconsiderable, or too uninteresting mine the washing rooms, which are situated or about 44 cents for an American pound. to require an entire periodical, and eager to a few hundred yards from the mines. The The quantity annually procured is about communicate every information to an ingangue containing the metal is carried to one hundred and sixty-four tons: formerly quirer, are obliged to reflect, and make this house, and if it is of the earthy kind, it was greater, and brought a better price, special arrangements, before they can deit is broken up and thrown upon large seives, their market, which is chiefly in China, vote a few hours to a stranger. by means of which the loose or native having been injured by competion from the quicksilver (called here yung frau or virgin quicksilver mines near Almeria, in Spain. quicksilver) is separated from the earth-[Am. Journal of Science and Arts.] the latter is then cast into shallow boxes open at the ends and a little inclined, and a gentle stream of water being made to pass over it, a rake is used, and the earthy matter is carried off. There are seven of these boxes in succession, and by the time the residuum reaches the last of them, it resembles a heavy gray powder, and is sufficiently pure to be carried to the vapor furnace. The stony fragments require only a slight washing to cleanse them from the outward earthy impurities.
From the Annals of Education.
Coblentz, on the Rhine, Nov. 26, 1835,
Unexpected circumstances of a private
The furnace is half a mile lower down
The doors of the chambers are then carefully walled up; and a strong fire having been lighted under the centre building, the quicksilver rises in the form of vapor, and passing into the small chambers, is there condensed by the cold atmosphere around them. Some of the gangue, you will observe, is brought here in the form of the native rock: I understood them to say that the expansive power of the vapor, together
with the heat of the fire, was sufficient to
a few of our teachers.
It is not less striking to a stranger, to find men of all professions who speak so decidedly as to the necessity of religious
school instruction. But I must reserve this
topic for a separate article, in order to do it
In passing through Cologne, seven years since, I visited the school Inspector of that district, and found him in the midst of a mass of papers, assisted by a secretary. He received me with great kindness, and gave me such documents as would aid me in my inquiries; but as my stay was short, he could not lay aside or arrange his occupations so as to allow me much time for conversation. In my present hurried journey was unable to call upon him.
At Neuwied,* on the Rhine-a few miles from this city-I stopped to visit a public seminary for teachers; and here I found several able men whose whole time and power were devoted to study and experimode of "keeping a school"a task for ment and instruction as to the best which any youth of seventeen, any poor scholar of a college, any one who is unfit for any other profession, is quite competent in our country; and all this care and labor is even wanted on elementary schools. When will it be seen that it is a more delicate, a more difficult task to be the teacher of a school of children, than to be a professor in university? The seminary at Neuwied, will describe hereafter, when I have leisure to copy and complete my notes.
In Coblentz I found two school officers,
who received me with great kindness, and in whom I was much interested. One was Catholic who has given up his office, but who had just returned from a tour, in which he had assisted in organizing a Catholic seminary for teachers. I could not but wish that some of our statesmen could have seen the spirit with which a man, whom they would not hesitate to receive into their ranks could enter upon, and speak of this humble, or, as I regard it, this noble employment.
The other gentlemen is a Protestant, the inspector of this district. I found him also in the midst of his business-and it was not
cause the rock to disintegrate and thus allow Justice-I will only remark, in passing, till he had examined his papers and memo
that they consider our practice on this subthe escape of the quicksilver. When this process is over, the door ways of the cham-ject as equally unchristian and impolitic; as preparing our way to the grave of free nabers are once more opened, and the quick-tions; as increasing the spirit of licentious silver, which is found chiefly adhering in liberty to such a point that we shall be drops to the sides and ceiling, is scraped obliged to admit, if we do not demand, off, and running into a hollow in the floor, military despotism. is taken thence to the cleaning and bottling
To one who feels that on the education of the young depends the destiny of his
randums, that he could venture to promise that he would see me on that day. He invited me to the evening meal of his family. The opportunity was, however, so precious, that I could scarcely give up any of its moments to that free, social intercourse, which is so characteristic of a German family; and I found so much patience and
It appears to act on the mortar of the chambers, for I found the latter flaky, country, and all the objects of affection it indulgence with my inquiries, that I was
and the crevices all filled with small glo
contains; who believe that the progress
This gentlemen was kind enough to give tempted, I fear, almost, to exhaust it. me, in parting, several interesting pamphlets, and also a copy of some of his obsevaHe has since been so attentive as to send tions in MS, during his tour of inspection,
The cleaning process is very simple, a cation is the only means of enlightening piece of canvass being merely spread over and civilizing and christianizing the world, a funnel, and the quicksilver being made to it is truly cheering to find some of the most pass through this, comes out sufficiently eminent and able men of church and state, pure, That intended for home consumption devoted to the single duty of studying and is then tied up in sheepskins, while that for examining-of making experiments and *This place will be remembered by some, as the reexportation is put in iron bottles large enough ascertaining results, in this "science of sidence of Maximilian Prince of Neuwied, who published his travels on the Rhine. He has a fine col to contain sixty-eight pounds. The furnace sciences"-men too, who know and feel,lection here of American animale,