Page:Encyclopædia Britannica, Ninth Edition, v. 11.djvu/336

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316
GUN—GUN

tageous terms, and now India supplies vast quantities of gunnies to Europe, Egypt, Ceylon, the Malayan Archipelago, China, and the United States. In America alone it is computed that the annual average outturn of cotton is 3,500,000 bales, each bale requiring G yards of wrapping material, and of this one-third at least is supplied in gunny cloth. In 1872-73 6,105,275 gunnies and G4,347 pieces were exported from India, whilst in 1876-77, during a period of eleven months, 30,110,616 gunny bags and 5,262,835 yards of guuny cloth were exported to foreign countries. These figures do not include what is sent coast

wise or what is used for packing exported Indian produce.

Bombay too has machinery for weaving jute, but has not as yet done much to compete with Bengal, and indeed there appears little hope for Bombay unless large quantities of jute can be made to grow on the spot, since, apart from the cost of carriage, the juices in the jute plant, as in many other plants, become resinified by drying, and therefore require operating upon whilst perfectly fresh, being attended after treatment with more difficulty iu manipulation and a less outturn of fibre.

The excellent gunny bags sent to England are often used for repacking for exportation, and large quantities find their way to paper mills.

 


GUNPOWDER


 

UPON the great importance of the invention of gun powder it is needless to dwell. Not only has it revolutionized the art of war, and given the forces of civiliza tion a vast advantage over mere numbers and savage valour, but we may even urge, paradoxical though it appears, that the very improvements by which modern science has ren dered military machines more deadly tend to make war far more expensive, and therefore to prevent its being so fre quently or so rashly undertaken as of old. Besides such indirect services to civilization, gunpowder has been and is of great use in the arts of peace, although of late years to a certain extent superseded by more potent explosive agents,

Such being the case, it is not a little remarkable that the discovery of gunpowder should be veiled in uncertainty, although this very obscurity seems proof of its great anti quity. It is, however, certain that it was not invented, as has been often stated, by the German monk Bertholdus Schwartz, about 1320, although Wilkinson, in his Engines of War, considers Schwartz may have suggested the use of a mortar, since the form as also the name of this piece of ordnance may well have been due to some accident in the laboratory. Roger Bacon, who was born in 1214, refers, circa 1267, to an explosive mixture of the nature of gunpowder as known before his time, as being employed for purposes of diversion, and as producing a noise like thunder, and flashes like lightning ; he even suggests its application to military purposes, and indulges in the supposition that some such composition might have been employed by Gideon to destroy the Midianites (Judges vii.). He elsewhere writes " Ex hoc ludicro puerili quod fit in multis mundi partibus, scilicet, ut instrumento facto ad quantitatem pollicis humani, ex hoc violentia salis, qui salpetroe vocatur, tain horribilis sonus nascitur in ruptura tarn modicse pergamenae, quod fortis tonitru rugitum et coruscationem maximam sui luminis jubar excedit" (see preface to Jebb s edition of Bacon s Opus Majus). In the above pa-sage saltpetre is alone referred to as the violently explosive substance, but Bacon was well aware of the fact that saltpetre of itself will not explode, for in his previously written treatise, De Secretis Operihus Art is et Natures et de Nullitate Magia>, he siys " that from saltpetre and of her ingredients we are able to make a fire that shall burn at any distance we please." In chap. xi. of t ue same work these other ingredients are veiled in the disguise of an anagram : " Sed tamen salis petrae lura nope cum ubre et sulphuris, et sic facies tonitrum et coruscationem, si scias artificium ; " the unmeaning words in italics have been translated as carbonum jndvere. Robins, in his work on gunnery (1742), and Dutens (Enquiry into the Origin of Discoveries attributed to the Modern*) suggest that Bacon may have derive:! his know ledge from the MS. of Marcus Gnecus, preserved in the National Library in Paris, entitled " Incipit Liber Ignium a Marco Graeco prescriptus, cujus virtus et efficacia est ad comburendum hostes, tarn in mari quam in terra." Marcus Graacus, who lived about the end of the 8th century, was therefore not ignorant of the military uses to which the composition might be put ; among other modes of launching fire upon an enemy he gives one to the following effect : one pound of live sulphur, two of charcoal of willow, and six of saltpetre, reduced to a fine powder in a marble mortar and mixed together; a certain quantity is to be put into a long, narrow, and well compacted cover, and then discharged into the air. This is evidently the description of a rocket. It has also been suggested that Bacon may have learnt the secret in Spain, in which country he is known to have travelled, and whose Moorish masters were then far in advance of the rest of Europe in science and literature. Albertus Magnus, in his treatise De Mirdbilibus Mundi, repeats almost word for word several receipts in the work of Marcus Graecus ; also, an epistle by Ferrarius, a Spanish monk, and a contemporary of Bacon, which is preserved in the Bodleian Library at Oxford, gives receipts for Greek fire, rockets, and " thunder." There is a treatise on gunpowder in the library of the Escorial, written about 1250, which appears to describe both rockets and shells ; the Arabians are, from this and other authorities, supposed to have enclosed combustible or explosive com positions in hollow globes of iron, which were discharged upon the foe either by hand, like the modern grenade, or from the warlike machines then iu use ; it has also been stated that towards the close of the 13th century they projected small balls from tubes carried in the hand, or attached to the end of a lance, and only used at close quarters, being in fact hand-guns. Rockets were employed during the reign of the Greek emperor Leo, about 880, and indeed seem to have been known in India from time immemorial, some of them having been made of great size.

The gloom of the dark ages precludes further attempt to trace back the history of gunpowder with any certainty, but Mr Dutens, in the work before quoted, adduces many passages from classical authors in support of his view that a composition of the nature of gunpowder was not unknown to the ancients, as, for example, the story of Salmoneus, king of Elis, who, according to Virgil (Aeneid, vi. 585), for his audacity in attempting to imitate thunder and lightning, was slain by Jupiter; Mr Dutens considers he may have fallen a victim to his own experiments. Eustathius, a commentator on Homer, speaks of him as being so skilled in mechanics that he constructed machines to imitate thunder (Eustathius ad Odyss., A 234, p. 1682, 1. 1 ; see also Hyginus, Fabul., 61, 650; Valerius Flaccus, lib. i. 662). It is also narrated of Caligula by Dion Cassius (Hist. Rom., "Caligula," p. 662) that he had machines which imitated thunder and lightning, and emitted stones. See also Johannes Antiochinus, Chronica apud Peiresciana Valesii, Paris, 1604, p. 804.