OHAKUNE EXPLOSION

Otago Witness, Issue 3250, 28 June 1916, Page 54

OHAKUNE EXPLOSION

EXPERT EVIDENCE

OHAKUNE, Juno 22

The inquest regarding the Ohakuno explosion was resumed to-day before the Coroner (Mr Aldridge) and a jury of six. Mr Macassey represented the Public Works Department and Mr Harris tile relatives of the deceased.

Dr Maclaurin gave evidence that he investigated the quarry and found samples of explosives in perfect order. He was sure that tho accident, was not due to defective explosives. Witness explained the way the wiring of explosives was carried out. Tiie wires ran from the explosives along the roof of the tunnel and hung down near the mouth ready for testing or joining up with similar wiring in the other two tunnels, preparatory to all'being fired simultaneously. In his opinion the explosion was due to misadventure. In testing tho wires tho custom was to tost them with a galvanometer. Ho thought the testing had been carried out because portion of a galvanometer was found near tho tunnel. Tho current generated was 0.05 amperes, and to fire tho detonator .6 amperes was necessary. Tho red seal dry batteries produced were found, and might have been used. Ho could not think they would have any other use for them at a quarry. Some galvanometers would not produce current. Rod seal colls could be used providing the current, was passed through a galvanometer, but grave danger arose because it was easy to inadvertently touch the wires together instead of touch-

ing the galvanometer poles. He wanted fo emphasise this, as he was satisfied that the explosives were not decomposed. There was no evidence that cells wire u.;eil, but he assumed so. Robert Holmes, engineer to the Public Works Department, agreed with the possibility of I)r Maclaurin's theory. It would not be wrong- to use the ceils for testing with a galvanometer of sufficient resistance. Nobel's possessed sufficient. lie knew lh ; s was so because lie and Dr Maelaurin had proved it by experiments. Considering the nearness of the poles on Nobel's it was risky in use an outside cell. The appearance of tee red seal cells was such 'as indicated that they had been subjected to the force cf air caused by explosion. Michael Sheedy, recalled, said lie had seen cells similar to those produced 0:1 the staging between the tunnels.