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Show amount of stripping an compared with tho tons of oro laid bare Is a small as In tho case of tho Boston company, will always be cheaper than nny underground un-derground method that can be devised. de-vised. The underground system at present being Installed can only be looked upon as a means of tiding over the time until a way can be devised to return to steam shovel mining, and treating the resultant concentrateg under un-der a smelting: contract based upon a , greater knowledge of the relative amounts of iron and rnsolubles In such '. concentrates. I The report estimates that It will j cost $165,000 Snd tako throe months' ! time to uncover enough ore to keep hajf the mill supplied with ore from J the steam shoveling. Mr. Jennings j states that tho work of tho mill, as a whole, can be Judged by the results so far obtained and that they arc better than he anticipated they would be. He looks for an actual recovery In tho mill this year of at least 7 per cent, s It is estimated that the costs with one-half the production coming Trom underground mining and one-half from j steam shoveling will be 212.7 cents per ton. This can only be made arter the mill has been working a sufliclent j time at full capacity to get it In per- j feet running order, and whllo the mill ; may be supplied to its full capacity from underground mining in April, it will be well towards the end of the year before the low working costs can be looked for. The net number of tons that should be recovered from the average oro is 19.5. Mr. Jennings estimates the cost of copper with the i mill running at full capacity one-halt I irom ore irom underground mining and one-half from steam shoveling at 10.5 cents por pound, after deducting gold and silver values. He states as to the sulphide mine that the values arc so variable and the number of tona available so indeterminate, that It is better to look upon any profits derived from this source as a means of tiding over until tho mill Is working work-ing to its full capacity. It Is possible, however, he states, that vigorous prospecting pros-pecting may disclose au exceedingly valuable property. The report ends with the following: "The development of the underground mine should be pushed until such time as the full extent of the payable oro In the porphyry mine is more accurately accurate-ly known. The mill should be brought up to its fu'l capacity at the earliest possible date, and should bo worked at such capacity until such time as the figures for working costs can be verified. veri-fied. If those figures prove to be as estimated in this report, thou suttl-cent suttl-cent capacity of the mill, to permit of enough stripping to be done to permit per-mit of steam shovel mining, and to provide sufficient trading capital to finance fi-nance six months' work of the mine and mill, and the necessary excess development in the porphyry mine' MINING NEWS I ADVOCATES SHOVEL WORK ON BOSTON. The report of consulting engineer for the Boston Consolidated. Sidney J. Jejiuings. presented at the annual meeting of the company contains a strong endorsement of tbe steam rhovel system in the Bingham prop-ertv. prop-ertv. In his report to the company. Mr" Jennings has had the following to fay: Mining by steam shovel when the |