Imagens da página

oxide of either iron, lead, or manganese, / parts by weight of Nordhausen sulphuric 2 parts of glass powder, and from 2 | acid, specific gravity 1.84, and 1 part of to 3 parts strong glue or gum. These nitric ait, specific gravity 1:5; this matches will ignite only on the friction mixture allowed to cool down-a prosurface thus prepared. 2. For the cess which occupies two or three days match-heads a mixture of chlorate of | —before the cotton is placed in it. After potash and a compound of hyposulphur- immersion, the charges of cotton are ous acid with soda, ammonia, and oxide strained until each contains only about and sub-oxide of copper. This com- 10 times its weight of acids, and each pound is formed by dividing a solution charge is then placed in an earthenware of copper into two equal parts, super- 1 jar and covered down. In order to presaturating one of them with ammonia, vent any heating from taking place, the and the other with hyposulphate of jars should be placed in a current of soda; then mixing the two solutions, and cold water. The cotton after being exstirring the mixture well, a violet pow- posed to the acid for 48 hours, in order der precipitates. One part of it is to | to ensure its thorough conversion, is be mixed with 2 parts of the chlorate of removed from the jars and squeezed potash, and a small quantity of pounded nearly dry. It is then to be suddenly glass. Lucifers made in this way are, plunged into a strong fall of cold water, however, objectionable, from the fact and left for a short time. The object of that they will ignite on any rough sur- | placing the gun-cotton in the fall of face, even more easily than the common water is to ensure the sudden and comkind.

plete submersion of the material, and Gun-Cotton. - There are several | thus avoid the heating and decomposivarieties of gun-cotton — the explosive, tion of the cotton, which would take soluble only in acetic ether; pyroxiline, place at the surface of the water if the soluble in sulphuric ether and alcohol ; cotton were immersed gradually. On and syloidine. All these are formed by its removal from the fall of water, the the action of nitric acid on cotton orgun-cotton is wrung dry, and placed in lignine in some form. The difference a stream of water for 48 hours. After between them consists mainly in the being washed and partly dried several strength and temperature of the acids times more, the cotton should be employed in their preparation. The thoroughly dried at the temperature of most explosive is prepared with the no more than 140° F. It is now so exstrong acids, sulphuric and nitric, mixed, plosive that great care is required in its the object of the sulphuric being to take arrangement, being about three times as water from the nitric, and so leave the explosive as gunpowder. As thus prelatter in its full strength to combine pared gun-cotton scarcely differs from with the lignine or cotton. The first unchanged cotton in appearance; it is thing to be done is to thoroughly cleanse white and fibrous, and rather harsh to the raw material. This is effected by the touch. If only a small quantity is boiling it in an alkaline solution, then required-1. Mix 41 oz. of pure, dry, drying it in a current of air, and then nitrate of potash with 30 fluid drachms again boiling it in clean water. After of sulphuric acid, sp. gr. 1.845, and stir the second boiling it must be very into this mixture carefully 120 grs, of thoroughly dried at about 120° F. The best carded cotton. As soon as saturacotton must be very thoroughly dried, tion is complete, in about one minute, if as any moisture which might remain in proper care has been used, throw the it would, by combining with the acid, cotton into a large pan of clean rain generate heat, and set up a destructive water, and change the water repeatedly action. The cotton, in charges of 1 lb., | until litmus ceases to show the presence is placed separately in a bath containing of acid, then squeeze it in a cloth, and, the mixed acids, the mixture in which after being well pulled out, dry it at the cotton is submerged consisting of 3 | a temperature of about 180o. 2. Take of cotton 1 oz., sulphuric acid, 5 fl. oz., / pared in this manner, nitro-glycerine is nitric acid, 5 fl. oz.; mix the acids in a an oily-looking liquid, of a faint yellow porcelain mortar, immerse the cotton in colour, perfectly inodorous, and possessed the mixture, and stir it for three minutes of a sweet, aromatic, and somewhat piwith a glass rod, decant the liquid, pour 1 quant taste. It is poisonous, small doses more water on the mass, and repeat the of it producing headache, which may process until the washing ceases to give also be produced if the substance is aba precipitate with chloride of barium. | sorbed into the blood through the skin, Drain the product on filtering paper and and hence it is not desirable to allow it dry in a water bath.

to remain long in contact with the skin, Nitro-Glycerine. — Nitro-glyce- | but rather to wash it off as soon as posrine is made in the following manner : sible with soap and water, Glycerine Fuming nitric acid (sp. gr. about 1:52) has a specific gravity of 1.25-1•26, but is mixed with twice its weight of the the nitro-glycerine has a specific gravity strongest sulphuric acid, in a vessel of almost 1.6, so that it is a heavy kept cool by being surrounded with cold liquid. It is practically insoluble in water. When this acid mixture is pro-water, but it readily dissolves in ether, perly cooled, there is slowly poured into in ordinary vinic alcohol, and in methyit rather more than 1 of its weight of lic alcohol or wood spirit. If it is syrupy glycerine; constant stirring is simply exposed to contact with fire it kept up during the addition of the gly- does not explode, although it is so powcerine, and the vessel containing the erful as an explosive. A burning match mixture is maintained at as low a tem may be introduced into it without properature as possible by means of a sur ducing any explosion ; the match may rounding of cold water, ice, or some be made to ignite the liquid, but comfreezing mixture. It is necessary to bustion will cease as soon as the match avoid any sensible heating of the mix- ceases to burn. Nitro-glycerine may ture, otherwise the glycerine, which is even be burned by means of a cotton the sweet principle of oil, would be, to a wick or a strip of bibulous paper, as oil considerable extent, transformed into from a lamp, and as harmlessly. It oxalic acid. When the action ceases, remains fixed and perfectly unchanged nitro-glycerine is produced. It forms at 212° F.; if heated to about 3600, on the surface as an oily-looking Auid, however, it explodes. It detonates when the undecomposed sulphuric acid form- struck by the blow of a hammer, but ing the subjacent layer, owing to its only the part struck by the hammer exgreater specific gravity. The whole plodes; the surrounding liquid remains mixture is then poured, with constant unchanged. As the carriage of nitrostirring, into a large quantity of cold glycerine is dangerous, many trials have water, when the relative specific gra- been made to render it inexplosive, and vities become so altered that the nitro- to restore its explosiveness with equal glycerine subsides and the diluted acid readiness. Nobel's method of making rises to the surface. After the separa- it inexplosive is at once simple and tion in this manner into two layers is effective. It is to mix with it from 5 to effected, the upper layer may be removed 10 per cent. of wood spirit, when all by the process of decantation or by attempts at exploding it are rendered means of a siphon, and the remaining utterly futile. Five per cent, of methylnitro-glycerine is washed and re-washed alcohol is said to be amply sufficient to with fresh water till not a trace of acid transform the nitro-glycerine into the reaction is indicated by blue litmus inexplosive or protected state, but 10 paper. The final purifying process is to per cent. is generally added before sendcrystallize the nitro-glycerine from its ing any liquid into the market. The solution in wood naphtha. The final | transformation of protected into ordiprocess is not necessary when the com | nary nitro-glycerine is effected by thopound is to be used at once. As pre- / roughly agitating it with water, and

allowing the mixture to settle for a stains all the properties of nitro-glycerine short time. By this means the water for blasting, but is not so dangerous, dissolves out the methyl-alcohol, and the as it may be handled freely. Explosion mixture of spirit and water readily rises is produced by means of a percussion to the surface, in virtue of its low spe- cap in the same manner as with nitrocific gravity, and can be removed by | glycerine. means of a siphon, or by simply pouring Fulminates.-Fulminate of Merit off. As a blasting liquid it is now cury. — 1. This highly-explosive comready for use. If protected blasting pound consists of protoxide of mercury liquid be kept in a closed vessel, it will united with an acid; fulminic acid, remain in that state for an indefinite formed of cyanogen and oxygen. Fulperiod of time, and ready at any moment minate of mercury is prepared by causing to be reduced or rendered fit for action; alcohol to react on the acid protoif, however, it be exposed in an open nitrate. A quantity of mercury is disvessel, it will regain its explosiveness, in solved in 12 parts of nitric acid of 35° or periods of time proportionate to the 40° of Baumé, and 11 parts of alcohol amount or degree of exposure. For at •86 are gradually added to the solublasting purposes, the chief advantage tion; while the temperature is slowly which nitro-glycerine possesses is that it elevated, a lively reaction, accompanied requires a much smaller hole or chamber by a copious evolution of reddish vathan gunpowder does, the strength of pours, soon ensues, when the liquid, on the latter being scarcely to that of the cooling, deposits small crystals of a yelformer. A chamber, 34 millimètres in lowish white colour. Fulminate of mer. diameter, was made perpendicularly in cury is one of the most explosive coma dolomitic rock, 60 ft. in length, and pounds known, and should be handled at a distance of 14 ft, from its extremity, with great care, especially when it is which was nearly vertical. At a depth dry, and it detonates when rubbed of 8 ft., a vault filled with clay was against a hard body. It dissolves reafound, in consequence of which the dily in boiling water, but the greater bottom of the hole was tamped, leaving portion is again deposited in crystals a depth of 7 ft. One litre and a half of during cooling. The fulminating matenitro-glycerine was then poured in; it rial of percussion caps is made of fui. occupied 5 ft. A match and stopper minate of mercury prepared as just were then applied as stated, and the mine stated, after having been washed in cold sprung. The effect was so enormous as water. The substance is allowed to to produce a fissure 50 ft, in length, and drain until it contains only about 20 per another of 20 ft. Nitro-glycerine has, cent. of water, and is then mixed with however, one disadvantage. It freezes of its weight of nitre, which mixture at a temperature very probably above is ground on a marble table with a 92° F., and it is said that even at a tem- muller of guiacum-wood. A small perature of 43° to 46° F. the oil solidi- quantity of the paste is then placed in fies to an icy mass, which mere friction | each copper cap and allowed to dry, the will cause to explode. It is probable, fulminating powder in the cap being however, that the freezing-point of the often covered with a thin coat of varnish oil lies somewhat lower than is here to preserve it from moisture. 2. Weigh stated, though as yet no exact determi- | out 25 grains of meroury in a watchnation of the freezing-point of the oil | glass, transfer it to a half-pint pipkin, has been made. Great care must be ex add a measured oz. of ordinary conercised whilst it is in a frozen state, as centrated nitric acid, sp. gr. 1.42, otherwise it will cause most dreadful and apply a gentle heat. As soon as the accidents.

mercury is completely dissolved, place Dynamite is made by mixing 75 | the pivkin upon the table away from per cent. of nitro-glycerine with 25 per any Aame, and pour quickly into it, at cent. of powdered sand. Dynamite re-arm's length, 5° measured drachms of alcohol, sp. gr. 0.87. A brisk action plosion, and is dangerous whilst still will ensue, and heavy white clouds will moist. arise. When this action has subsided, Fulminating Platinum.—Dissolve binfill the pipkin with water, allow the oxide of platinum in diluted sulphuric fulminate to settle, and then pour off acid, mix the solution with excess of the liquid acid. Collect the fulminate | ammonia, a black precipitate is obon a filter, and wash with water as tained, which detonates violently at long as the washing tastes acid, then dry | about 400° F. by exposure to the air. This explodes Fulminating Gold.-Add ammonia to a at a temperature of 360° F., or by being solution of terchloride of gold; the buff touched by a glass rod which has been precipitate which it deposits is violently dipped in concentrated nitric or sul- | explosive at a gentle heat. phuric acid. An electric spark also | Terchloride of Gold.—Dissolve gold in explodes it.

hydrochloric acid, with one-fourth of its Fulminate of Silver. - Dissolve 10 volume of nitric acid. Evaporate on a grains of pure silver, at a gentle heat, in water bath to a small bulk; when cool, 70 minims of ordinary concentrated ni- yellow prismatic crystals of a compound tric acid, sp. gr. 1.42, and 50 minims of of the terchloride, with hydrochloric water. As soon as the silver is dis- acid are deposited, from which the hysolved the heat is removed, and 200 drochloric acid may be expelled by a minims of alcohol, sp. gr. 0.87, are gentle heat, not exceeding 250° F. The added. If the nitric acid and alcohol terchloride forms a red brown deliquesare not of the exact strength here given cent mass, which dissolves very readily it may be difficult to start the action, in lin water. which case add two or three drops of Gunpowder. – The component red nitric acid, which contains nitrous parts of gunpower are saltpetre, sulacid. Standard silver, containing copper, phur, and charcoal, used in the followmay be used for the preparation of the ling proportions :-1. English war powfulminate. If the action does not com- der.-Saltpetre, 75 parts; sulphur, 10; mence after a short time, a very gentle charcoal, 15. 2. French war powder. heat may be applied until effervescence Saltpetre, 75 parts; sulphur, 12:5; begins, when the fulminate of silver will charcoal,' 12:5. 3. French sporting be deposited in minute needles, and may powder. --Saltpetre, 76:9 parts; sulbe further treated as in the case of ful- 1 phur, 9.6; charcoal, 13.5. 4. French minate of mercury. As the fulminate of blasting powder.-Saltpetre, 62 parts; silver is exploded much more readily sulphur, 20; charcoal, 18. There are a than the fulminate of mercury, it must number of variations of the above rebe handled with the greatest caution ceipts; but the difference, which is when dry. It should be separated into purely a matter of opinion, consists small quantities, each portion wrapped principally in varying the quantity of in paper, and kept in a cardboard box, sulphur or charcoal employed. nothing harder than this should be Šaltpetre.-Crude saltpetre cannot be brought in contact with it. This mix- used for making gunpowder. The crysture is of no use for percussion caps, talline flour, quite free from chloride, being too violent in its action.

is the best for the purpose. The washThrow-down Detonating Cracker. - ing process is carried so far that nitrate Screw up a particle of fulminate of silver of silver produces no precipitate in the in a piece of thin paper, with some frag- purified saltpetre. The general rule is ments of a crushed quartz pebble. to use the salt petre whilst slightly

Double Fulminate of Silver and Am damp, allowing for the proportion of monia.-Dissolve fulminate of silver in moisture when mixing with the other warm ammonia: the solution, on cooling, ingredients. This saves the processes of will deposit crystals of the double ful- drying and grinding the saltpetre before minate. This is very violent in its ex- | mixing with the sulphur and charcoal.

SULPHUR. — Refined sulphur in rolls | riorates by keeping. Charcoal that has is used. This must be reduced to an been too highly burned for war powder impalpable powder, which is usually is used in the manufacture of blasting effected by placing the sulphur in hollow powder, as that need not be so inflamwooden drums, having projections, or mable. brackets inside. A number of small Pulverizing.–The required quantities brass balls are put into the drum with of sulphur and charcoal are thoroughly the sulphur, and the drum is made to pulverized, and intimately mixed, by revolve for six hours, when the action being rolled for about four hours in a of the balls and projections reduces the cast-iron drum, with numerous small sulphur to very fine powder, which is brass balls, at a speed of about 28 revothen extracted through wire gauze. Any lutions a minute. When the mixture is small particles of sand, or unequally pul complete, the powdered sulphur and verized sulphur, are then separated by charcoal is removed from the drum, 3 bolting machine.

and a proportionate quantity of saltCHARCOAL.—The quality of the char petre is added. Great care must be coal depends greatly upon the material used in weighing out the various ingrefrom which it is obtained, and the dients, according to the quality of the manner in which it is prepared. The powder required, as upon that, and the soft, woody parts of plants, which yield complete mixing of the materials, the a friable, porous charcoal, leaving very success of the manufacture depends. little ash, are preferred. Black alder, Mixing.–The powder is put in a and spindle tree, poplar, chestnut, vine | mixing machine, which is a leather drum, stalks and willow, are most esteemed. | in which are placed numerous small Hemp-stalks, fibres of fax, and old linen bronze balls. The machine revolves at also yield a very good charcoal. Remove from 25 to 30 revolutions a minute, and the bark, leaves, and smaller branches, in about 4 hours' time the mixing is selecting branches from 1 to 2 inches in complete. thickness. These are to be cut into | Granulating. - The powder having lengths of 5 or 6 feet, and tied in bun- been damped and pressed into cakes, dles, weighing about 30 lbs. The wood must then be crushed to the required will not be injured by exposure to the size of grain. It is first roughly rain, as that tends to remove extrac- broken into lumps by small mallets; it tive matter. The carbonization is is then fed into the granulating machine, effected either in pits, or in cast-iron which is caused to revolve for 35 or 40 cylinders. The yield of charcoal is 18 | minutes, at about 10 revolutions a to 20 per cent., when prepared in pits; minute. A small stream of water enters and from 35 to 40 per cent. when pre the granulator ; the movement of the pared in the cast-iron cylinders. The machine rolling the damp grains conprocess of manufacture is similar to that stantly among the dry meal powder, adopted for ordinary charcoal, the pits causes the latter to adhere to their suror cylinders, however, replacing the or face, and each grain is thus increased by dinary kiln. If the charcoal is intended concentric layers. When the small meal for sporting powder, it may be with-powder is all absorbed by the action of drawn whilst of a brown colour, when the granulator, the material is placed in it is called red charcoal. This would a barrel ready for equalization. make a powder too explosive for war Equalizing.–The grains as they come purposes; this must be prepared from the from the granulator are of various sizes, black or distilled charcoal, which is more they are therefore sifted over two leacompletely calcined, and is used by all ther or parchment sieves, one of which English makers. The best quality has is pierced to separate the grains which a bluish black colour, is light, firm, and are too large, whilst the other allows all slightly flexible, and should be used im the dust to pass through, retaining only mediately it is made, as it rapidly dete the grains which are of the desired size.

« AnteriorContinuar »