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GUNPOWDER
, an explosive composed of See also:saltpetre, See also:charcoal and See also:sulphur
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Very few substances have had a greater effect on See also:civilization than gunpowder
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Its employment altered the whole See also:art of See also:war, and its See also:influence gradually and indirectly permeated and affected the whole fabric of society
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Its See also:direct effect on the arts of See also:peace was but slight, and had but a limited range, which could not be compared to the See also:modern extended employment of high See also:explosives for See also:blasting in See also:mining and See also:engineering See also:work
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It is probably quite incorrect to speak of the See also:discovery of gunpowder
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From modern researches it seems more likely and more just to think of it as a thing that has See also:developed, passing through many stages—mainly of improvement, but some undoubtedly See also:retrograde
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There really is not sufficient solid See also:evidence on which to See also:pin down its invention to one See also:man
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As See also:Lieutenant-See also:Colonel H
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W
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L
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Hime (Gunpowder and See also:Ammunition, 1904) says, the invention of gunpowder was impossible until the properties of nearly pure saltpetre had become known
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The See also:honour, however, has been associated with two names in particular, Berthold Schwartz, a See also:German See also: Of the former Oscar Guttmann writes (Monumenta pulveris pyrii, 1904, p . 6): "Berthold Schwartz was generally considered to be the inventor of gunpowder, and only in See also:England has Roger Bacon's claim been upheld, though there are See also:English writers who have pleaded in favour of Schwartz . Most writers are agreed that Schwartz invented the first See also:fire-arms, and as nothing was known of an inventor of gunpowder, it was perhaps considered justifiable to give Schwartz the See also:credit thereof . There is some See also:ambiguity as to when Schwartz lived . The See also:year 1354 is sometimes mentioned as the date of his invention of See also:powder, and this is also to be inferred from an inscription on the See also:monument to him in See also:Freiburg . But considering there can be no doubt as to the .manufacture in England of gunpowder and See also:cannon in 1344, that we have See also:authentic See also:information of guns in See also:France in 1338 and in See also:Florence in 1326, and that the See also:Oxford MS . De officiis regum of 1325 gives an See also:illustration of a See also:gun, Berthold Schwartz must have lived See also:long before 1354 to have been the inventor of gunpowder or guns." In See also:Germany also there were powder-See also:works at See also:Augsburg in 1340, in See also:Spandau in 1344, and See also:Liegnitz in 1348 . Roger Bacon, in his De mirabili potestate artis et naturae (1242), makes the most important communication on the See also:history of gunpowder . Reference is made to an explosive mixture as known before his See also:time and employed for " diversion, producing a See also:noise like See also:thunder and flashes like See also:lightning." In one passage Bacon speaks of saltpetre as a violent explosive, but there is no doubt that he knew it was not a self-explosive substance, but only so when mixed with other substances, as appears from the statement in De secretis operibus artis et naturae, printed at See also:Hamburg in 1618, that " from saltpetre and other ingredients we are able to make a fire that shall See also:burn at any distance we please." A See also:great See also:part of his three chapters, 9, Io, 11, long appeared without meaning until the anagrammatic nature of the sentences was realized . The words of this See also:anagram are (See also:chap . II): " See also:Item ponderis totum 30 sed tamen salis petrae luru vopo vir can utri et sulphuris; et sic facies tonitruum et coruscationem, si scias artificium . Videas tamen utrum loquar aenigmate See also:aut secundum veritatem." Hime, in his See also:chapter on the origin of gunpowder, discusses these chapters at length, and gives, omitting the anagram, the See also:translation: " Let the See also:total See also:weight of the ingredients be 30, however, of saltpetre . . . of sulphur; and with such a mixture you will produce a See also:bright flash and a thundering noise, if you know the See also:trick . You may find (by actual experiment) whether I am See also:writing See also:riddles to you or the See also:plain truth." The anagram reads, according to Hime, " salis petrae r(ecipe) vii part(es), v nov(ellae) corul(i), v et sulphuris (take seven parts of saltpetre, five of See also:young See also:hazel-See also:wood, and five of sulphur) . Hime then goes on to show that Bacon was in See also:possession of an explosive which was a considerable advance on See also:mere incendiary compositions . Bacon does not appear to have been aware of the projecting See also:power of gunpowder . He knew that it exploded and that perhaps See also:people might be blown up or frightened by it; more cannot be said . The behaviour of small quantities of any explosive is hardly ever indicative of its behaviour in large quantities and especially when under confinement . Hime is of See also:opinion that Bacon blundered upon gunpowder whilst playing with some incendiary See also:composition, such as those mentioned by See also:Marcus Graecus and others, in which ' These words were emended by some authors to read luru mope can ubre, the letters of which can be arranged to give pulvere See also:car. bonum . he employed his comparatively pure saltpetre instead of crude nitrum . It has been suggested that Bacon derived his knowledge of these fiery mixtures from the MS . See also:Liber ignium, ascribed to Marcus Graecus, in the See also:National Library in See also:Paris (See also:Dutens, Enquiry into Origin of Discoveries attributed to Moderns) . Certainly this Marcus Graecus appears to have known of some incendiary composition containing the gunpowder ingredients, but it was not gunpowder . Hime seems to doubt the existence of any such See also:person as Marcus Graecus, as he says: " The Liber ignium was written from first to last in the See also:period of See also:literary forgeries and pseudographs .
. . and we may reasonably conclude that Marcus Graecus is as unreal as the imaginary See also:Greek See also:original of the See also:tract which bears his name." Albertus See also:Magnus in the De mirabilibus mundi repeats some of the receipts given in Marcus Graecus, and several other writers give receipts for Greek fire, rockets, &c
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Dutens gives many passages in his work, above-named, from old authors in support of his view that a composition of the nature of gunpowder was not unknown to the ancients
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Hime's elaborate arguments go to show that these compositions could only have been of the incendiary type and not real explosives
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His arguments seem to hold See also:good as regards not only the Greeks but also the See also:Arabs, See also:Hindus and See also:Chinese (see also See also:FIREWORKS)
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There seems no doubt that incendiary compositions, some perhaps containing See also:nitre, mostly, however, simply combustible substances as sulphur, See also:naphtha, resins, &c., were employed and projected both for See also:defence and offence, but they were projected or blown by engines and not by themselves
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It is quite inconceivable that a real propelling explosive should have been known in the time of See also:
J
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A
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See also:Conde Wistaria de la dominacion de los Arabes en Espana) states that See also:Ismail See also:Ben Firaz, See also:
Preserved in the Record See also:Office in London are See also:trust-worthy accounts from the year 1345 of the See also:purchase of ingredients for making powder, and of the See also:shipping of cannon to France
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In 1346 Edward III. appears to have ordered all available saltpetre and sulphur to be bought up for him
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In the first year of See also:Richard II
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(1377) See also: Most if not all the early powder was a " loose " mixture of the three ingredients, and the most important step in connexion with the development of gunpowder was undoubtedly the introduction of wet mixing or " incorporating." Whenever this was done, the improvement in the product must have been immediately evident . In the See also:damp or wetted See also:state pressure could be applied with See also:comparative safety during the mixing . The loose powder mixture came to be called " See also:serpentine "; after wet mixing it was more or less granulated or corned and was known as " corned "powder . Corned powder seems to have been gradually introduced . It is mentioned in the Fire See also:Book of See also:Conrad von Schongau (in 1429), and was used for See also:hand-guns in England long before 156o . It would seem that corned powder was used for hand-guns or small arms in the 15th century, but cannon were not made strong enough to withstand its See also:explosion for quite another century (Hime) . • According to the same writer, in the period 1250-1450, when serpentine only was used, one powder could differ from another in the proportions of the ingredients; in the modern period—say 17oo–1886—the powders in use (in each state)differed only as a See also:general See also:rule in the See also:size of the See also:grain, whilst during the transition period—1450–1700—they generally differed both in composition and size of grain . Corned or grained powder was adopted in France in 1525, and in 1540 the See also:French utilized an observation that large-grained powder was the best for cannon, and restricted the manufacture to three sizes of grain or See also:corn, possibly of the same composition . Early in the 18th century two or three sizes of grain and powder of one composition appear to have become See also:common . The composition of English powder seems to have settled down to 75 nitre, 15 charcoal, and 10 sulphur, somewhere about the middle of the 18th century . The composition of gunpowders used in different countries at different times is illustrated in the following tables: English Powders (Hime) . 1 1250 . 1350 . 156o . 1647 . 1670 . 1742 . 1781 . Saltpetre . 41.2 66.6 50.0 66.6 71.4 75•o 75.0 Charcoal . 29'4 22'2 33.3 16.6 14.3 12.5 15.0 Sulphur . 29.4 11.1 16.6 16.6 14.3 12.5 10.01 1 This represents the composition of English powder at present, and no doubt it has remained the same for a longer time than We above date indicates . See also:Foreign Powders (Hime) . France . See also:Sweden . Germany . See also:Denmark . France . Sweden . Germany . 1338 . 1560 . 1595 . 1608 . 1650 . 1697 .
1882
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Saltpetre
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50 66.6 52.2 68.3 75.6 73 78
Charcoal
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? 16.6 26.1 23.2 13.6 17 19
Sulphur 25 16.6 21.7 8.5 10.8 to 31
1 See also: 1-3% of hydrogen and 8-15% of oxygen generally remain in charcoals suitable for gunpowder . A good See also:deal of the fieriness and violence of explosion of a gunpowder depends on the mode of burning of the charcoal as well as on the wood from which it is made . Properties of Ingredients.—Charcoal is the See also:chief combustible in powder . It must burn freely, leaving as little ash or See also:residue as possible; it must be friable, and grind into a non-gritty powder . The sources from which powder charcoal is made are See also:dogwood (Rhamnus frangula), willow (Salix See also:alba), and See also:alder (Betula alnus) . Dogwood is mainly used for small-See also:arm powders . Powders made from dogwood charcoal burn more rapidly than those from willow, &c . The wood after cutting is stripped of bark and allowed to See also:season for two or three years . It is then picked to See also:uniform size and charred in cylindrical iron cases or slips, which can be introduced into slightly larger cylinders set in a See also:furnace . The slips are provided with openings for the See also:escape of gases . The rate of heating as well as the See also:absolute temperature attained have an effect on the product, a slow rate of heating yielding more charcoal, and a high temperature reducing the hydrogen and oxygen in the final product . When heated for seven See also:hours to about 800° C. to 900° C. the remaining hydrogen and oxygen amount to about 2 % and 12 % respectively . The time of charring is as a rule from 5 to 7 hours . The slips are then removed from the furnace and placed in a larger iron vessel, where they are kept comparatively See also:air-tight until quite See also:cold . The charcoal is then sorted, and stored for some time before grinding . The charcoal is ground, and the powder sifted on a rotating See also:reel or See also:cylinder of See also:fine mesh See also:copper-See also:wire See also:gauze . The sifted powder is again stored for some time before use in closed iron vessels . Sicilian sulphur is most generally employed for gunpowder, and for See also:complete See also:purification is first distilled and then melted and cast into moulds . It is afterwards ground into a fine powder and sifted as in the See also:case of the charcoal . See also:Potassium nitrate is eminently suitable as an oxygen-provider, not being deliquescent . Nitrates are continually being produced in See also:surface soils, &c., by the oxidation of nitrogenous substances . Nitric and nitrous acids are also produced by electric discharges through the atmosphere, and these are found eventually as nitrates in soils, &c . Nitre is soluble in See also:water, and much more so in hot than in cold . Crude nitre, obtained from soils or other sources, is purified by recrystallization .
The crude material is dissolved almost to saturation in boiling water: on filtering and then cooling this liquor to about 30° C. almost pure nitre crystallizes out, most of the usual impurities still remaining in See also:solution
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By rapidly cooling and agitating the nitre solution crystals are obtained of sufficient fineness for the manufacture of powder without special grinding
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Nitre contains nearly 48 % of oxygen by weight, five-sixths of which is available for See also:combustion purposes
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Nearly all the gases of the powder explosion are derived from the nitre
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The specific gravity of nitre is 2.2: 200 grams will therefore occupy about See also:loo cubic centimetres See also:volume
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This quantity on its decomposition by See also:heat alone yields 28 grams or '22,400 C.C. of See also:nitrogen, and 8o grams or 56,000 c.c. of oxygen as gases, and 94 grams of potassium See also:oxide, a fusible solid which vaporizes at a very high temperature
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See also:Incorporation.—The materials are weighed out separately, mixed by passing through a See also:sieve, and then uniformly moistened with a certain quantity of water, whilst on the See also:bed of the incorporating See also: The mills are provided with a drenching apparatus so arranged that in case of oae mill firing it and its neighbours will be drowned by water from a cistern or tank immediately above the mill . The product from the incorporation is termed " mill-cake." After this incorporation in the damp state the ingredients never completely separate on drying, however much shaken, because each particle of nitre is surrounded by a thin layer of water containing nitre in solution in which the particles of charcoal and sulphur are entangled and retained . After due incorporation, powders are pressed to a certain extent whilst still moist . The See also:density to which a powder is pressed is an important See also:matter in regard to the rate of burning . The effect of high density is to slow down the initial rate of burning . Less dense powders burn more rapidly from the first and tend to put a great See also:strain on the gun . Fouling is usually less with denser powders; and, as would be expected, such powders See also:bear transport better and give less dust than See also:light powders . Up to a certain pressure, hardness, density, and size of grain of a powder have an effect on the rate of burning and therefore on pressure . See also:Glazing or polishing powder grains, also exerts a slight retarding action on burning and enables the powders to resist atmospheric moisture better . Excess of moisture in gunpowder has a marked effect in reducing the explosiveness . All powders are liable to absorb moisture, the quality and kind of charcoal being the See also:main See also:determinant in this respect ; hard burnt black charcoal is least absorbent . The material employed in brown powders absorbs moisture somewhat readily . Powder kept in a very damp atmosphere, and especially in a changeable one, spoils rapidly, the saltpetre coming to the surface in solution and then crystallizing out . The pieces also break up owing to the formation of large crystals of nitre in the mass . After the pressing of the incorporated powder into a " See also:press-cake," it is broken up or granulated by suitable machines, and the resulting grains separated and sorted by sifting through See also:sieves of determined sizes of mesh . Some dust is formed in this operation, which is sifted away and again worked up under the rollers (for sizes of grains see fig . 1) . These grains, cubes, &c., are then either polished by rotating in drums alone or with See also:graphite, which adheres to and coats the surfaces of the grains . This See also:process is generally followed with powders intended for small-arms or moderately small See also:ordnance . Shaped Powders.—Prisms or prismatic powder are made by breaking up the press-cake into a moderately fine state, whilst still moist, and pressing a certain quantity in a See also:mould . The moulds generally employed consist of a thick See also:plate of See also:bronze in which are a number of hexagonal perforations . Accurately fitting plungers are so applied to these that one can enter at the See also:top and the other at the bottom . The See also:lower plunger being withdrawn to the bottom of the plate the hexagonal hole is charged with the powder and the two plungers set in See also:motion, thus compressing the powder between them . After the desired pressure has been applied the top plunger is withdrawn, and the lower one pushed upward to eject the See also:prism of powder . The axial perforations in prism powders are made by small bronze rods which pass through the lower plunger and See also:fit into corresponding holes in the upper one . If these prisms are made by a steadily applied pressure a density throughout of about 1.78 may be obtained . Further to regulate the rate of burning so that it shall be slow at first and more rapid as the powder is consumed, another See also:form of See also:machine was devised, the See also:cam press, in which the pressure is applied very rapidly to the powder . It receives in fact one See also:blow, which compresses the powder to the same dimensions, but the density of the |