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by his faith.” And, as a representative man, / paratively, have anything but the very haziHabakkuk has bequeathed to believers in est notions regarding nitro-glycerine, that Christ's Church, even in “ the last plagues,” we deem it almost necessary--at all events this standing prayer of “ patience of hope,” | desirable-to give such a sketch of its but of“ a contrite spirit: “ O Lord, revive birth, history, nature, properties, and uses, thy work in the midst of the years, in the as shall be tolerably in accordance with truth, midst of the years make known; in wrath and so devoid of technicalities that it shall remember mercy.”

interest in some degree all those persons “He which testifieth these things saith, who wish information on one of the things Surely I. come quickly; Amen. Even so, not generally known.” At the same time come, Lord Jesus."

T. 1. it is not undesirable to mention thus early Bexley.

that the writer is firmly convinced that nitro-glycerine is already a practical utility,

and that it has an important future in store From The Westminster Review. for itself. He is not a manufacturer of the NITRO-GLYCERINE: THE NEW EXPLOSIVE. substance, neither is he a manufacturer's 1. Watts' Dictionary of Chemistry. Long- agent, and, consequently, he cannot be mans. Vol, ii. 1864.

charged with having interested motives in 2. Chemical News. Vols. xiii., xiv., xvi. saying a good word for this reviled subLondon, 1866-7.

stance, and asking for it that fair play of 3. British Association Reports. 1856.

| which we Englishmen consider ourselves 4. Comptes Rendus, tome lxiü. 1866.

the champions. . 5. Berg und hüttenmännische Zeitung. 1867.1. Nitro-glycerine had its birth in the chem 6. American Artizan. 1866.

ical laboratory of the eminent French profes 7. Scientific American. 1866.

sor, M. Pelouze, now upwards of twenty 8. American Journal of Mining. 1866. years ago. The person who brought it into 9. Private communications, &c. &c.

existence, and added to the already count

less family of chemical compounds, was M. In the early part of the year 1866 the Ascagne Sobrero, a young Italian, who was substance known as nitro-glycerine, or blast- then a student under Pelouze, and is now a ing oil, was for the first time ushered into professor in the Technical Institute of Tuvery prominent notice to most ordinary peo- rin. By bringing a mixture of strong nitric ple, and even to many scientific people, in and sulphuric acids -- that is, common aquaa very unusual and decidedly unceremonious fortis and oil of vitriol - into intimate con manner. An explosion then occurred which tact with glycerine, he found that he had was attended with the burning and ultimate produced a new compound which proved to destruction of the steamer European, one of be the very antithesis of glycerine, a subthe West India mail packets, while she was stance whose properties constitute it one of lying at the port of Colon or Aspinwall, on the best illustrations of neutral chemical the Atlantic side of the Isthmus of Panama. bodies, a substance which has no positive As nitro-glycerine was known to have been chemical activity about it, but is one of the on board, under the name of “glonvine," most sluggish and do-nothing bodies known or “glonvin oil," and as it was known also to chemists. This new compound, on the that it was on its way to the gold mining other hand, proved to be possessed of exdistricts of the North American Pacific plosive power of such extraordinary violence States as an explosive or blasting agent, it as to be almost incredible. was immediately concluded that the explo- In a few words, the following is some sion was due to this substance, and to it thing like an outline of the process by only — whether rightly or wrongly we do means of which nitro-glycerine may be prenot take time to inquire. . On the 17th of pared for use : - A mixture is made of four December last an explosion of extraordina- parts or measures of oil of vitriol and two ry violence, and proving fatal to seven per-parts of strong fuming nitric acid, the spe sons, happened much nearer home, namely, cific gravity of which is as nearly as may be on the Town Moor of Newcastle-on-Tyne; 1.52. When this acid mixture has thorand in this instance there is no room for oughly cooled down, one part or measure doubt, as it is absolutely certain that nitro- of glycerine in the dehydrated state that glycerine was the material which then and is, free from water-is poured into it and there exploded with such dreadfully fatal con- the whole well stirred. Chemical action ensequences. Much that has been spoken and sues, attended with considerable increase written regarding this Newcastle explosion, of temperature and with the escape of ruddy and the substance concerned in it, has been brown fumes. To prevent the temperature so very incorrect, and so few people, com- l becoming too great, the vessel is externally

cooled by being surrounded with ice. When gloved when working with vessels containthe chemical action ceases, it is found that ing it. Notwithstanding what has frequently a yellowish oily-looking fluid comes to the been said to the contrary, since the Newsurface: this is impure nitro-glycerine. To castle explosion, and in some instances said obtain it in the pure state, free from con- authoritatively by scientific men, nitro-glytaminating acid, the whole liquid mass is cerine per se, and when prepared in a pure thoroughly mixed with fifteen or twenty state, is a very stable compound at ordinary times its bulk of cold water, and then per- temperatures; if, however, it be impure, mitted to settle. The nitro-glycerine col- and contain any of the acid used in preparlects in the lower part of the vessel and is ing it, there is a proneness to decomposition, drawn off by means of a siphon, or separa- and not only so, but decomposition even ted by the process of decantation. It is with explosive violence is almost certain to afterwards washed so completely that not occur. "When quite pure it will safely bear the slightest trace of acid is found in the exposure to the temperature of boiling wawashings. The great importance of this ter, namely, 212° Fahr. It is not in the precaution will be seen shortly.

slightest degree volatile; it is practically if What we have now in imagination pre- not even absolutely insoluble in water, but pared is nitro-glycerine — a substance whose in ether, alcohol, and especially wood-spirit chemical nature is, in every sense of the or methyl-alcohol, it is freely dissolved. term, both curious and interesting. Its sci- The property which especially characterizes entific name has misled some of the ready this substance is its explosiveness, or, to be writers of the newspaper press regarding more exact, its great explosive power, for its composition. Not possessing any pro- it is not exploded with any unusual degree found knowledge of chemistry, it was almost of facility. Of this property more shortly. natural that they should say one or more Various persons have worked on nitroof them that it consists of nitrogen and glycerine since it was first discovered by glycerine, and that the statement when once Sobrero. Amongst others there may be made, and made with a show of learning, mentioned Railton, Dr. J. H. Gladstone, should readily get currency, as was the case De la Rue, Kapp, Dr. de Vrij, and beyond immediately after the Newcastle explosion. and above all others, Mr. Alfred Nobel, a Like ordinary cotton or cellulose, glycerine, Swedish gentleman of great scientific atthe material started with, consists of the tainments. It was while acting in the cathree elementary substances - carbon, hy-pacity of a mining engineer that Mr. Nobel drogen, and oxygen; but when treated in became acquainted with this wonderful subthe manner already indicated, a nitro-com- stance, and he quickly saw that as a blastpound results which contains the same three ing agent it might become immensely useful. elements, the amount of hydrogen, however, He instituted numerous experiments in orhaving undergone a diminution, and a quan- der that he might become thoroughly ac tity of the nitric acid in a somewhat altered quainted with its properties, and in order, or reduced form having taken its place. likewise, that he might be able to prepare it Although prepared from glycerine, the nitro- in a state of absolute purity, and of perglycerine obtained does not, strictly speak- fectly uniform quality, so that it might be ing, contain that substance either; it is a secured against all that tendency to spontanew product entirely, consisting of nitricneous decomposition which had been obacid that has parted with some of its oxy- served by some of the earlier experimenters gen, and glycerine that has been robbed of with it, and which is still spoken of by very a portion of its hydrogen, as already men- recent writers. tioned. So much then for its name and its What the Austrian General Von Lenk did real composition; and now as to its proper- for gun-cotton or nitro-cellulose, the Swedties.

| ish mining engineer did for nitro-glycerine; Nitro-glycerine, when perfectly pure, is a he removed it from the laboratory and docolourless liquid, decidedly heavier than main of the scientific and theoretical chemglycerine (the specific gravities being, re- ist, and made it, in the hands of the practical spectively, about 1.600 and 1.200), per man, one of the realities of modern manufectly inodorous, and possessed of a sweetish, factures - one that could be carried out on aromatic, and pungent taste. It is power- a large scale, and still with that amount of fully poisonous, and even a small quantity rigidly scientific exactitude that is required placed on the tongue produces violent head in the circumstances of the case. Mr. Noache, and headache may also result from the bel patented his process in the principal absorption of nitro-glycerine through the countries of Europe, and in America, and skin into the blood. On this account it is shortly thereafter commenced to manufacvery desirable that the hands should be ture nitro-glycerine in the outskirts of the

free city of Hamburg, whence it is sent to tact with the liquid for some time, till the almost all parts of the world where a blast- latter gets heated, it will burn with flame, ing agent is required.

but without explosion; and if the bar be To proceed now with the further consid- removed, unconsumed nitro-glycerine may eration of the properties of this substance. still be found remaining, providing that the

As an explosive agent, nitro-glycerine is whole of the wetted surface has not been almost unique amongst chemical compounds. actually covered by the hot iron bar. Now, Almost all explosive and detonating sub- gunpowder will explode with a simple spark, stances are nitro-compounds, consisting, as such as is produced by the sharp friction of they do, of two or more elementary ingre- a flint in contact with steel. Gun-cotton dients of which one is the element nitrogen. will actually explode at a temperature of Gunpowder - although it is not a definite 277° Fahr., a heat which is not very much chemical compound of its ingredients, salt- greater than that of boiling water. It will petre, sulphur, and charcoal, but rather a explode by contact with a wire that has been mechanical mixture of these ingredients exposed but for a very brief space of time very intimately and skilfully incorporated in a candle or gas flame. Of the ease with is a sufficiently good illustration. "Nitrogen which gun-cotton may be exploded, the is present in the nitre or nitrate of potash, following circumstance may be taken as an in the form of nitric acid. Gun-cotton also illustration :- A scientific lecturer was recontains nitric acid, although in a somewhat cently performing to an interested audience modified or deoxidized state ; and the same, the very beautiful and familiar experiment in a sense, is true of fulminating mercury, of burning a piece of watch-spring in a the substance used for charging percussion small glass jar of oxygen gas. The amount caps, and fulminating silver. The elements of burning steel was also very small; the chlorine, bromine, and iodine, form explo- amount of heat evolved could not, theresive compounds with nitrogen, known as the fore, be very great; but still it was great chloride, bromide, and iodide of nitrogen. enough to act by radiation in such a way The compound last mentioned is a solid that a quantity of gun-cotton was ignited body, and is probably the most sensitive ex- which was some inches away from the small plosive substance known, a touch with a point of combustion. A gentleman who feather being quite sufficient to cause its ex- has used tons of nitro-glycerine, and perplosion ; but the nitro-compounds of chlo- formed all sorts of experiments with it, says, rine and bromine are oily-looking liquids, in a letter to the lecturer sympathizing with and in the possession of this peculiarity him on account of the scorching which his there is a close resemblance between them face met with,_"Nitro-glycerine would and nitro-glycerine. The explosive sub- not have played you such a trick." The stance under notice is probably the only present writer has had a good deal of expeliquid compound of organic origin that pos-rience with nitro-glycerine, and can bear sesses explosiveness, and in this sense it testimony to the truth of the remark just certainly is unique; still more so is it unique quoted. He has also been informed of iu being the only liquid explosive that has another instance of the readiness with which yet been rendered serviceable to man. gun-cotton ignites. It was proved by an

It is a very curious explosive withal, in- incident that must have been painfully seasmuch as heat alone will not explode it, vere to the operator, yet it had a humorous unless the heat be raised to about 360° Fahr. aspect also: - A photographer, who had It will not explode by simple contact with prepared some gun-cotton to be used in fire. To demonstrate this fact, a quantity making collodion, was drying it upon a of the nitro-glycerine may be put in a sau- tray in front of the fire, and while engaged cer or other shallow vessel, and then a in turning it over very cautiously it flashed burning match or splint of wood may be off in his face, without giving him any warnplunged into and employed in stirring the ing, and instantaneously disappeared. In explosive liquid, but no explosion will oc- course of time the injury was attended with cur; the liquid will simply burn with a the removal of the entire skin of his face. flame, which immediately goes out if the The photographer's face was pock-marked burning body be withdrawn. The nitro- before the accident, but after the injury glycerine may be burned from an ordinary was healed (although the writer does not cotton wick, just like common lamp oil. If vouch for the truth of the statement, still it a quantity of it be spread over a flat stone deserves to be true), the pock-marks no or a smith's anvil, and then a red-hot iron longer existed to disfigure his face. bar be drawn along the surface of the nitro-! It is as a blasting agent that nitro-glyceglycerine, the liquid will not catch fire; if, rine has been specially used during the last however, the bar be allowed to lie in con- / three or four years : how it is used as such

falls now to be explained and illustrated. | or even water, is introduced above the From what has been already stated, it may nitro-glycerine as the tamping material. be concluded that some other agent than Hard tamping or stemming is very objecheat must be employed to effect its explo- tionable; as just mentioned, water will sufsion : that agent is concussion. A very sim- fice; for, as the nitro-glycerine is fully one ple and perfectly harmless experiment may and a half times the weight of water, and be performed in illustration in starting. A insoluble in it, the latter will rise to the surquantity of the explosive liquid is spread face, even though the drill-hole contain over the surface of an anvil or a plane-faced water when the nitro-glycerine is poured weight — say a fourteen-pound weight; on into it. From this circumstance, it will be striking the moistened surface sharply with seen that nitro-glycerine may be used in wet a hammer, there will be a detonation or rocks or water-bearing strata with impuniexplosion; but, remarkable to relate, how-ty, while gun-cotton and gunpowder would ever, only that portion of the liquid will be useless. When the blasting liquid is in explode which is actually struck, and there the drill-hole, the fuse, tipped with a tightmay be as many detonations produced as ly-fitting percussion-cap, is introduced into there are strokes made on the weight or an-it, either before or after the tamping is vil where it is wet with nitro-glycerine. To done; but, whether before or after the explode the substance in mass, as in blast- tamping, it is in all cases absolutely necesing operations, the mechanical disturbance sary to see that the cap is actually in the must be effected in some other way. One blasting liquid. is to have at the end of the fuse a small bag When the explosion is effected there is of gunpowder actually dipping into the no residue, neither is there any smoke, and blasting liquid ; another is to use a percus- the explosion is much quicker than that of sion-cap, of extra strength, at the end of gunpowder; hence the blasting operations the fuse. There must be great mechanical may be performed with greater than ordinary violence comparatively, and yet, from the rapidity. When rocks are much fissured results of numerous experiments with this this rapidity of the explosion is of great most curious and wonderful substance, that consequence, as the force does not get time mechanical violence must be exerted in a to spend itself through the fissures, but acts peculiar way. Glass bottles filled with it immediately in the vicinity of the place ochave been experimented on times without cupied by the blasting liquid. Perhaps the number. They have been dashed against most striking circumstance in connexion hard rocks, or from considerable heights, with nitro-glycerine, as a blasting agent, is with as great force as could be exerted by the fact of its being the most powerful ex

the experimenters, and yet explosion of the plosive known; it possesses most enormous • nitro-glycerine has not resulted. It is need- power, and of this a single explosion re

less to say that the bottles have been broken moves all doubt where any doubt or unbeinto a thousand fragments. In one case lief exists. Dead weight, simply, is not a that has been recorded, a commission of good standard of comparison to set up in five scientific gentlemen superintended some point of economy; but even suppose that experiments of which the following is one: to be taken, one pound of nitro-glycerine - Three glass bottles were filled with nitro- will do as much mechanical work as ten glycerine, and, in order to show the com- pounds of gunpowder, and some persons bined effort of heat and concussion, they have affirioed that it is even equal to thirwere heated in hot water to a temperature teen pounds of gunpowder. As regards the of 120° Fahr., and then thrown violently cost, it should be mentioned that, weight against a stone; the bottles were smashed, for weight, nitro-glycerine costs seven times but none of the blasting liquid exploded. as fouch as gunpowder; yet still its use is In another experiment, two tin canisters, attended with very great economy, of which such as the nitro-glycerine is sold in, were evidence will shortly be aduced. When filled with the liquid and packed in the the extraordinary force of this new blasting usual way in a wooden box, the cover be material began to make itself known, about

ing tightly screwed on, the box was thrown two and a half or three years ago, in various * down upon a rock at a depth of some nine mining districts in Sweden, Switzerland, or ten feet, but no explosion took place. Belgium, France, and a mraber of German

When it is desired to employ this sub- states, great enthusiasta was almost invaristance as a blasting agent, drill or bore ably created by it in the minds of quarrymen, boles are made in the usual way, just as if miners, maining engineeri, railway con gun-cotton or gunpowder were to be used. tractors, &c., and more esperially when it They are filled up to a sufficient height with was found that its storage, carriage, and the liquid, and then rock-powder or sand, use were attended with as great safety na

T

was the case with gunpowder. Such state- | this question of economy: “The final re ments regarding nitro-glycerine as the fol- sult of three months' blasting with nitrolowing were deliberately put in writing by glycerine shows a saving, as compared to men of a plain, practical, and prosaic turn what it cost us to blast with gunpowder, of of mind, not men with beated imagina- 23 per cent. on the cost of the blasting (mations:

terials included) ;” and that “the progress

of the tunnel has been 87 per cent. quicker “The enormous explosive power of this mar-than when we made use of gunpowder, vellous substance has proved of great value to which has proved of great indirect benefit," me. The statement made as to its power I con- Another railway contractor says: “ Through sider noways exaggerated.”.

the use of nitro-glycerine the blastings of Nitro-glycerine is a real conquest ; and all the Great Northern Railway (of Sweden the persons present at the experiments we alluden

have been contracted for at the reduced to unanimously declared that it will constitute one of the most important agents for industrial

price of 75 per cent. of what we paid when purposes.”

"I gunpowder was used." “It opens a new era in the mining business."

| Testimony of this sort could also be “ The trials with the blasting oil showed an given at great length, were it desirable to effect so marvellous that we have resolved to use do so. nothing else for our blastings."

| Most people who have read of explosions “This extraordinary power effects a valuable of nitro-glycerine have got some notion of the saving of time.”

extraordinary power of that substance; and "I have made use of nitro-glycerine for blast- those who have used it practically, or have ing limestone with the highest success, and been present at experimental demonstrafound it extremely profitable, as well as more tions of its great explosive effect, have no easy to use and less dangerous than gunpow

tions of a very decided character. For the der." “ An invention destined to play an important

benefit of the former the results of two or part in our mining operations and construction th

three practical illustrations of its power of railways is nitro-glycerine. It has effected a may be mentioned: complete revolution.”

In a Swiss slate quarry one pound weight “I have tried nitro-glycerine in the mines of of nitro-glycerine, in a 6. feet bore-hole, Pehrsburg, and found that, if the precautions and with water-tamping, completely scatprescribed are observed, it is less dangerous to tered 2000 cubic feet of rock. carry, to store, and to use than gunpowder.” In the red sandstone quarries in the vicin

ity of Eisleben, a town in Prussian Saxony, Such testimony could be continued at 3960 cubic feet of rock were removed by & very much greater length.

charge of two and a half pounds of nitroThe great explosive power of nitro- glycerine in one bore-hole 12 feet backglycerine renders it much more economical wards. than would appear to be the case at first Under the inspection of judges appointed sight. This greater economy is owing chiefly by the Royal Cornwall Polytechnic Society, to the fact that the drilling or boring of the to report on this substance, a charge of holes required for receiving the blasting four pounds completely scattered from agent, and which always forms a very large forty to fifty tons of rock, while the sur part of the expense of blasting, whether in rounding rock was rent in all directions. mines, quarries, tunnel-driving, or railway. In this experiment it was computed that cutting, is reduced to an exceedingly small had the hole been less in diameter, the same amount when nitro-glycerine is used, that effect would have been produced with a substance being so remarkably powerful much smaller charge. when compared with the bulk of it required From a mass of notes which have been to produce a certain given effect. Stated kindly furnished to the present writer by generally, it may be said that the average the managing director of a large slate quarresult as to economy hitherto, has been a ry in Wales, regarding actual operations saving of from 50 to 60 per cent. in quar- performed under that gentleman's superinries, and from 30 to 40 per cent. in mines, tendence, the following case may be quoted: on the cost of blasting. The bore-holes - A vertical hole, one inch in diameter, required are so few in number that there is five feet deep, and eleven feet from the face not only a saving of the workmen's time, of the rock, was charged with one pound of but there is also a saving in the expense of nitro-glycerine, the tamping being slateboring tools and fuse for exploding the dust. The jotting made in the note-book, charges. A railway engineer who directed immediately after the charge was exploded, the construction of a tunnel on the Stock- was, “ loosened all the rock in its immediholm Central Railway, says, in reference to I ate vicinity, say eleven feet by fifteen feet,

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