Cost of Production.

Progress, Volume III, Issue 9, 1 July 1908, Page 303

Cost of Production.

There is very little to go upon in the way of details of workings on the spot. It is remarked, however, in the Bulletin, that in the Masabi section of the L,ake Superior region

in the United States, where somewhat similar conditions prevail, the actual cost of mining is estimated at 80 cents, or 3s 4d the ton. In New Zealand, it is added, the average should not greatly exceed this amount, and mining operations might be conducted even more economically. In fact the ores, being exposed on the surface, ought to possess every facility for cheap and easy mining. Secondly, there are many suitable spots for blast furnaces which would command the ore from the three big blocks. There are two especially suitable, one on the Parapara inlet, the other on the banks of the Onakaka stream in a very extensive flat. Both have the easiest communication with the sea, and there is a certainty of fairly calm water, owing to the proximity of the sheltering Fare-

well spit, and the gradually shelving bottom is just fit for a wharf, which at low water could accommodate ships drawing thirty feet. Such a wharf is projected. Thirdly, " The necessary limestone flux for effecting the removal of the silica in the reduction of the ore, lies conveniently at hand. Some of the crystaline complex carbonates with which the ore bodies are generally associated, would certainly be suitable for this purpose, though doubtless a still better flux is to be found in the limestones of the Oamaru series occuring on the Parapara inlet the L,ower Parapara, and elsewhere." Fourthly, the coal question is not so pleasing as once seemed likely. There is coal at Puponga, very well leported on half a century ago by Hochstetter in his faciuatiug book on New Zealand, but it has been tried and found not to yield a hard enough coke

for smelting. At Pakawau, eight miles off on the Parapara inlet, there is a coal'which gives a fairly hard coke, but it contains too much sulphur for metallurgical purposes, and so far as has been ascertained at present, this coal is not in quantity sufficient. The Bulletin disposes of the question, however, by pointing to the Westport coal measures, distant 145 miles by sea. " The abundance of high class coal available in the Westport district affoids a coke eminently adapted for the requirements of the smelter, and no good reason appears to exist why it should not be landed at Parapara, at a cost consistent with extensive and profitable metallurgical operations." Summarising, we Jiave here at Parapara enormous quantities of high-class ore in posi-

tion most accessible, close to the sea, with no difficulties of embarkation. Abundances of fluxes are on the spot, and the coal for the smelting presents no difficulty. The minefield is marked, quoted, and signed by nature, for the establishment of a valuable iron industry ; it is now countersigned by opportunity ; and the opportunity is growing with rushing rapidity.

Machine varnishes or glazes are commonly employed for painting agricultural machines and are obtainable in a variety of colours, such as green, red, blue, etc. They must possess brilliant lustre and adhere to the iron almost as firmly as enamel. Ihey may be produced, of excellent ouahty, according to the following recipe. In 120 parts of 95 per' cent, alcohol dissolve 80 parts ot soft Manila copal, 40 parts ol resin, and when the solution is complete add 30 parts of castor oil. T Ins \ arnish is rubbed down, in the proportion ol '1 to 7, with anjdesired bright colour.