TREMENDOUS BLAST.

New Zealand Herald, Volume LXVII, Issue 20740, 6 December 1930, Page 2 (Supplement)

TREMENDOUS BLAST.

LIFTING LIMESTONE CLIFF.

ABOUT 30,000 TONS MOVED.

CHANGING OF NATURE'S FACE. The bones of n number of ancient Britons which /have lain peacefully for iinany centuries- in a " barrow " on the crest of Brierlow Hill, near Buxton, Derbyshire, got ii rude shaking on October 15 when some 30,000 tons of limestone rock were dislodged in their near vicinity. The blasting operation, which was the largest of its kind undertaken for some time, was arranged in the normal course of their work by the Beswick Lime Works Company. A distinguished company had been invited to view the blasting, including the Mayor and Mayoress of Buxton, and several aldermen, justices, and councillors of-the county. About 200 people in fill, including scattered groups of workmen, were gathered, says a correspondent of the Manchester Guardian, on a stretch of rising ground a little to the left of the rough face of the rook, which at this point rises sheer to a height of nearly 100 ft. Into this cliff a small army of tunnellers had been at work for weeks driving galleries and constructing special chambers in the rock where the high explosive might be laid. There was a sudden hush as the hoarse siren from the works ceased its fiveminute warning; a tiny figure with a

macintosh flapping round its legs raced away from the original cutting in the rock —known technically as a " heading " or " drift " —a passim,? 'bus halted to watch on the road far below; now only the birds continued to wheel and circle near the rock face. At a point on the top of the cliff three pigmy figures were still to be seen—these were the engineers in charge—one of them dropped a handkerchief; then they, too, disappeared. A moment afterward there was a low rumbling which burst into a roar. The bottom of the cliff blew out to a distance of twenty or thirty yards, and the top like Jill, came tumbling after. There was a mighty crash an the huge pieces of rock fell away from the body of the cliff, then a grinding as they dropped on to the original surface and slowly settled there; a mighty cloud of fine and very white dust flew u]) and covered the feet and clothes of a party of watchers, who were standing a quarter of a mile away. Then it was all over, and the spectators trooped across to get a nearer view. Thus, in an inshmt, can the whole face of the countryside be altered. A philosophical workman, turned to the writer: "Sometimes," be said, "I thinks we's gotten a cheek!"

Afterward, at lunch, the writer talked with one of the engineers. He said that the explosivo which is used nowadays for blasting operations such as these is a new and a "high " one, which is much safer than the old low explosive, " black powder," as it was called. There were less than 20001b. of " Ammonal Grain " in the three chambers dug in the rock for that, day's operation, and yet they were the equivalent to nearly four tons of black powder. Another improvement which has recently been effected in blasting work is the confinement of the actual task of exploding to a few experts. In tho old days almost every workman was entrusted with explosives, and habitually carried some cartridges, and even a detonator, in his pocket. Now ihs.t this haphazard system has been done away with the number of serious accidents has been cut down to a minimum.

The work is still hazardous, however, for sometimes after a tig shot there will still be huge lumps of rock overhanging, only one lump of which may weigh 100 tons, and tho workmen have to get at these from above, by ludder or swinging cran«,