IMPROVED DRILLING MACHINERY.
In the same report the improvement in drilling machinery is discussed, and Queensland manufacturers are congratulated on making American and Canadian machines with improvements which greatly add to their efficiency. Bores in Queensland are generally begun with 10-in. casing, and carried to not lower than 500 ft. Then 8-in., 6-in., and 5-in. casings are used. The necessity of these casings being as perfect as possible is emphasised by the Engineer. The cost of sinking bores by contract, which is almost the universal method, depends upon the facilities offered by the site for the transport of wood and water, but the range then was from 17s. to 24s. per foot for the first 500 ft., and increased with depth until, at 4,000 ft. odd, sinking had cost 55s. per foot. The inspectors appointed the previous year had done good work, though the wet season delayed travelling. Sectional diagrams compiled from the inspectors' reports appear among the appendices.
Then follows an interesting description of surface artesian water known as Elizabeth Springs, in latitude half a degree south of the tropic, and in 140¾ degrees west longitude. The account of these remarkable springs is well worth reading.[a]
[Footnote a:] See Votes and Proceedings for 1897 for Hydraulic Engineer's Report, 2nd October, 1896, page 5.
PROGRESS TO 1896.
Number of bores in Western Queensland to October, 1896, 454; average depth, 1,168 ft.; feet bored, 530,332 (nearly 100 miles); overflow, 193,000,000 gallons per diem. There were also nineteen deep bores on the coast. The total cost had been £928,081.
BORES IN THE GULF TOWNS.
Reporting on 2nd August, 1897, the Hydraulic Engineer mentions that the Burketown bore has been carried to a depth of 2,304 ft., with a supply of 155,560 gallons of good water at a pressure of 60 lb. per square inch, and a temperature of 155 degrees, the cost being £4,155. A few months earlier the Normanton bore had struck water at 2,330 ft., for 293,000 gallons a day, with a temperature of 151 degrees, at a total cost of £3,803.
PROGRESS COMPARED WITH SOUTHERN COLONIES.
The same report glances at the progress made in artesian water discovery in the southern colonies. Queensland aggregate flows on 30th June, 1897, were estimated at 140,000,000 gallons daily, or 51,135,000,000 gallons annually. This would suffice to cover 294 square miles with water 1 ft. deep, or 100 square miles 35⅓ in. deep. In New South Wales, in 1897, there were thirty-four flowing and twelve pumping bores, yielding 22½ million gallons of water per diem. In Victoria only one or two flowing bores had been put down, the country being generally unfavourable for artesian water. In South Australia there were in all sixty-two bores, seven being still in progress, but of the total only nineteen wells gave good fresh water, and twenty-two wells salt water. Seeing that artesian water exploration began in the three colonies named before any steps were taken in Queensland, the success here may be regarded as phenomenal, although of course a very considerable amount of capital was lost in sinking abortive bores.