A RECORD BLAST

Greymouth Evening Star, 13 September 1924, Page 3

A RECORD BLAST

THREE TONS Ob' GELIGNITE

(Per Press Association). AUCKLAND, Sept. 11,. A notable blasting operation was carried out at a stone quarry on the Waikato river bank, near liuikau by Mr W. A. Need, a contractor, three tons of gelignite were exploded to obtain metal for various reading contracts. ’ . Two cross-tunnels were borqd at ri <r ht angles to the main shaft, and at; the ends of these the explosives were laid. The main tunnel was’ 75 feet in length, and the length from the gelignite to l the mouth of the tunnet was filled with concrete. The shot, cue of the largest of its kind ever fired in New Zealand, was under the charge of Mr John Leggo, technical adviser to Nobel’s Explosive Company, Ltd., who was present at the firing, as also were representatives of Government Departments, mining experts, and a number of local residents. The. shot was fired electrically from the Tuakau bank of the river. There was practically no noise, but the ground was shaken as if by an earthquake for a distance, of more than half a mile around. The whole hillside appeared to lean outwards, hover as if in indecision, and then fall with a terrific crash. By means of the blast, 36,000 yards of rock were brought down, and a further 15,000 to 20,000 yards were shattered and loosened. The fall gave the. contractor sufficient metal for the next twelve months at the rate of 200 yards a day.