17G DYNAMITE 



'From the fine tortuous and branching veins which the rock forms, it scorns hardly 

 possible to suppose that at the time of its injection it was not in a fluid state and 

 almost perfectly liquid. The distances to which these narrow veins run seem also to 

 make it Accessary to suppose that, at the time of injection, it had a temperature not 

 merely just sufficient to melt it, but a much higher one ; sufficiently high to allow of 

 the loss of a considerable quantity of heat, and yet for the matter to remain still 

 molten in its passage to very considerable distances from the volcanic focus.' 



DYTiTAXVXXTX:. In 1867 Mr. Nobel, in his endeavours to lessen the dangers 

 attending the use of nitroglycerine, made the important observation that the readiness 

 or certainty with which it is exploded through the agency of a detonation is not 

 reduced, but, on the contrary, somewhat favored by mixing the liquid with solid 

 substances in themselves thoroughly inert. This discovery led at once to the pro- 

 duction by Nobel of solid, or more or less pasty, preparations of nitroglycerine, which 

 under the name of dynamite were first brought before the public in 1867. The form 

 in which dynamite was first presented to the public was that of a soft, readily-moulded 

 powder of a pink or buff colour, which consisted of about 75 parts of nitroglycerine 

 held absorbed by 25 parts of a porous, infusorial, silicious earth known in Germany as 

 'Kieselguhr'. The moist appearance of this powder favored the opinion that the 

 nitroglycerine would be liable to exude from it ; and it undoubtedly was open to this 

 objection. Dynamite has, however, been supplied for some time past in the form of 

 small cylindrical cartridges consisting of the material in a compact condition, enclosed 

 in a single wrapping of parchment-paper. These cartridges are consolidated by pres- 

 sure whereby any excess of nitroglycerine which the porous earth will not hold ab- 

 sorbed, is expelled, and thus the separation of the nitroglycerine in dressing, handling, 

 transport, or exposure to elevated temperatures appears effectually guarded against. 

 The consistence of the dynamite charges is like that of dry putty. The Kieselguhr 

 selected as the medium for the application of nitroglycerine appears the material best 

 calculated to hold absorbed a large proportion of the liquid, and to retain it even 

 when the mixture is submitted to considerable pressure. Mr. Abel, in his paper ' On 

 Explosive Compounds,' published in the 'Proceedings of the Institution of Civil 

 Engineers,' states that when dynamite factories were established in the outskirts of 

 Paris during the siege, and this particular silicious earth could not be procured, a 

 series of experiments was instituted for the purpose of discovering a good substitute. 

 The most efficient absorbents next to this material were found to be precipitated silica, 

 kaolin, tripoli, precipitated alumina and sugar, but none of these appeared thoroughly 

 equal to Kieselguhr in their power of retaining a very large proportion of the oil. 

 Eventually the ashes of Boghead coal were used for the production of dynamite during 

 the siege of Paris. Mr. Nobel's No. 2 dynamite, which is sold as a cheaper blasting 

 agent than the so-called No. 1, contains a much smaller proportion of nitro- 

 glycerine mixed with finely-powdered saltpetre, and resin or coal, but this cartridge 

 can only be used when the violent crushing and rending action of the stronger 

 dynamite is not required. 



The danger, real or supposed, attending the use of dynamite has led to many restric- 

 tions, not only on its manufacture, but on its transmission : the following particulars 

 contributed to one of our scientific periodicals in 1 873 will be read with some surprise 

 a few years hence : 



' Not very long ago a coasting screw steamer embarked a cargo of 42 tons of 

 dynamite at the Dynamite Company's works, on the Aryshiro coast, to be distributed 

 along the west coast of England and Wales at Whitehaven for the Cleator and 

 Furness haematite ironstone districts ; at Aberystwyth for Mid- Wales, at Cardiff for 

 South Wales, at Sydney for the mining districts of the Forest of Dean, Gloucestershire, 

 and the South Midland Counties; and at Hayle, in Cornwall, for the county, and 

 the adjoining county of Devon. Soon afterwards another cargo of 25 or 30 tons was 

 shipped and despatched to the north-oast coast of England vid the Forth of Clyde 

 Canal, to be delivered in varying quantities at Newcastle ; ;it Krdrnr, for llu- districts 

 of Cleveland and North Yorkshire; and at Goole, for East and "\YVst Yorkshire. 

 Since these arrangements have been put in train for establishing agencies in. and 

 sending large quantities of dynamite into, the North of Scotland Aberdeenshire, 

 Caithness, &c., and various parts of Ireland. More recently additional largo consign- 

 ments have been forwarded to the principal agents in England, and at present 

 arrangements are in progress for sending a very largo cargo down along the west co.-i-t. 

 The greatest proportion of the material yet despatched from the dynamite works 

 seems to have been greedily absorbed into use in the districts that are reached with 

 more or less ease from Whitehaven, and thither a number of consignments have found 

 their way, both by railway and steamer. 



' Great anxiety is being manifested to get largo supplies of dynamite sent out to llic 

 Australian colonies, and it is not unlikely that a ship-load will accordingly soon bo 



