WAR EXPLOSIVES

Dominion, Volume 8, Issue 2274, 7 October 1914, Page 8

WAR EXPLOSIVES

SHOCKS AT THE OPERA HOUSE. ; "An. unscientific lecture on a very scientific and technical subject," as he :terihediit, 'was delivered by Professor IV. H;' Easterfield at the Grand' Opera House last night. The subject was "War Explosives," and the lecture was designed to ewell the proceeds of. the Patriotic Fund. There was a fair attendance, but the lecture was of such an interesting nature that the Opera House should have been crowded. His Excellency the- Governor (Lord Liverpool), under whose patronage'the Jecture was given, was present. While everyone paid, close attention to the dracussion, it was the experiments .which were carried out that provided'the main attraction for most of those present. Professor Easterfield prefaced his remarks on "War Explosives" by dealing generally with the nature of ordinary explosions, and showed the difference, by experiment, between a slow explosion, travelling at a rate of 30ft. per second, and one travelling at the rate of 2000 ft. per second., The. latter, an acetylene explosion/shattered a ginger, ale bottle swathed in reveral cloth wrappings, which the professor held in his 'hand. The numbing effect on his fingers, he said, would taka from ten, to fifteen minutes to wear off. He left to the' imagination an explosion travelling- at a rate of from twenty thousand to thirty thousand feet per 'second, which would be- fast indeed. A most, interesting experiment was that in which he exploded, by means of a strong calcium light, directed on a glass a mixture of chlorine and hydrogen gases. The', gun was directed towards the wings of the stage. To in-

treduce an element of humour into his lecture, the Professor declared that he

had shot a German, and the "victim" ivas brought in. It proved to be a sketch of the Kaiser, plentifully- bespattered with. shot,. Later the ''father" was.placed alongside this drawing. It was that of a being usually supposed to dwell in. the nether regions, so' the lecturer had good game for his shots, and -delighted the- audience. Passing on to war explosives, Professor Eastertield first dealt exhaustive:

ly with the first; commercial explosive, gunpowder which he explained had almost entirely gone out or' use for propelling projectiles; But nitre, a siibBtance used in the manufacture of gunpowder, was still an essential part of all commercial explosives. This was largely obtained in India, but Germany had been most strenuous in an endeavour to niako this substance, to avoid the necessity of bring it through the English Channel. • Cheap electricity was necessity of bringing it through the Engmany had assisted in the' development of hydro-electric works in Norway, where there was plenty of water power. Tho Professor and his two assistants then proceeded to ■ manufacture some giineotloii. Instead of using cotton they utilised New Zealand flax, which/ soaked in /nitric acid, was a very good explosive. . Guncotton and nitre-glycer-ine incorporated, • and mixed with a little vaseline made cordite, which was used all over tho world as a propellant. This gave a greatly increased velocity to gunpowder. The "explosive- contained in the big gun shell was almost universally lyddite, which, though, very powerful in its action, required a strong-detonat-ing cap on the point of the projectile. To! secure this a mixture of fulminating mercury, nitric acid, and alcohol was used. This made a very powerful detonating cap. Professor Easterfield placed thirteen grains in a section of railway sleeper, and blew it in two, firing the cap by a fuse. He then electrically fired 27 grains, and the explosion was so great that a kerosene tin, in a case, had a great hole torn in it. In concluding, the lecturer expressed gratification at the fact that tho British Government was spending £30,000 per annum at the Woolwich Chemical Laboratory, on research in chemical explosives. For a long time, he said, the British Government had been content to follow the research of other nations, but they had at last realised tho necessity for a forward move. Professor Easterfield thanked all those ' who had assisted him in giving the demonstrations. -Ho was himself heartily applauded for the lecture