BLASTING AT MOSGIEL

Otago Daily Times, Issue 14282, 3 August 1908, Page 7

BLASTING AT MOSGIEL

A SEVEN-TON CHARGE. A blast of somewhat forge dimensions was firod at tJio Railway Department's quarry at Mosgiel oa Saturday morning, when a charge of seven lons of blasting powder was ignited. Metal was required for ballasting and other purposes, and the department presumably (nought it might |, c as well to do the thing thoroughly while it .was about it. A main dfivo was bored 60ft into the faee, branching at its inner extremity into two crosscuts, at right, angles to the drive, and 20ft each way. At tho end of cacli crosscut a '"poekcl." was constructed, and in each pocket was placed 3.1 tons of powder. Tho entire length of tlio crosscut was then tamped (packed tight with earth and sand), and the quarry, looking blankly ove.': the valley, gave no indications of tho potentialities pent within. To make, matters doubly sure two detonators had been fixttl to either pocket, and these were connected with a fixed battery placed 300 yards from tlvc quarry. At 10.30 a.m. an official touched tho instrument which was to release tho forces dormant in 6oven tons of powder. Both charged exploded simultaneously with a muffled roar. Tho ground throbbed once; and after a. pause those concerned v.cut forward to see tho K-sult. About 15,000 yards of metal had been hurled into tho quarry itself; while another 60,000 yards wa.s in a condition hnown to minors as " shook "—ready to come away by itself, or with a little assistance from a crowbar. An official, on being asked if seven tons of tamped powder was not rather overwhelming, replied casually: "Oh, it's a fair enough charge."