THE Inangahua Times. PUBLISHED TRI-WEEKLY. MONDAY, JAN. 12, 1880.

Inangahua Times, 12 January 1880, Page 2

THE Inangahua Times. PUBLISHED TRI-WEEKLY. MONDAY, JAN. 12, 1880.

A props of the project which will be shortly laid before the public of the Inaugabua for the driving of I,OOOft of the Black's Point Low Level Tan* nel, some information has jusfc be^n published by the Government which | throws a good deal of light upon the question of the probable cost. The Government communicated with Dr Hector, at Sydney, with reference to the latest improvements in rock* boring machines, and received much valuable information in return, Dr Hector, in the course of bis reply says : — " No. 1, or the hydraulic machine, is at present in use in Moor Park, and has bored to a depth of 1,830 ft with rods If inches in diameter- The core brought up 's 2 inches, and the hole left is 2| inches in diameter. This machine has bored the last 1000 ft in five weeks through compact gritty sandstone, ironstone, and black shale. ; Price of machine, £1,575, complete, or without steam boiler, £1,300, No. 2 machine is in use at Botany Bay, j and with the saxe size rods has bored 1,900 ft. Its present progress is 10ft per day, the total weight of the rods being io,ooolb, whiah are turned at the rate of 250 revolutions par minute, with a 10-horse power boiler. Price of machine, with one thousand feet of rods, £1,575. No. 3. This is a small machine with a detached boiler, as io No. 1, which was in use at Newington, when it bored to 500 feet, running a core of If inches diameter. It is not now in use. The price is £750, or £500 without the boiler; l^o. 4. This is a^so a smaller machine intended for tunnelling and preparing blast boles, which takes out a f inch core at any angle downwards, forward, or upwards for 100 feet distance with a 2-horse- power engine anel separate boiler ; but is also adapted for working with the same air compressor as the ordinary rock-drill. The price of the small machine, without a boiler, is £320. The rods used in all the machines are of a peculiar make, being hollow, and formed by rolling them in tough sheet" iron in a threefold cylinder. They can be supplied at the following rate : 7s 6d per foot for 1| inches diameter, 9s per foot for 2f inches* diameter. As far as I can judge the perfow mance of these machines is most satisfactory, and they would effect a great saving of time and expense in exploring for mineral ground at the Thames, and tbeir use might lead to a revival of the mining industry there, As the chief object at the Thames would be to determine the position aud boundaries of the bosses of un« decomposed rock in which no re« munerative reefs are to be expected, borings of considerable depth might be required, bo that one of the larger machines, either No, 1, or No, 2 would be most useful. As the work done might lead to very important results as regatds individual interets, Government might find it necessary, if the first attempts were sufficiently successful, to create a demand for the services of the machine, to charge for its use, either according to the work done or for the hire of the machine i'self. Dr Hector concludes by forwarding a copy of the conditions under which the machines are worked in Sydney by the Company which holds the patent right of the Australian colonies