The copper era., 1911-01-27

condition which 1t was believed call
 ed for dry crushing of the ore. Ex periments were conducted, of course
 and the result is today very perfect 1 rushing plant, situated just above
 he regular concentrator in such .
 way that, if necessary, the product
 # the crusher might be carried tC
 che concentrator by gravity. Thus
 you see ] have had week of the best
 kind of education in the concentra
 tion of ores, as we'll as in smelting
 [ have been visiting mining camps and works for a good many years, but
 Clifton Morenci appear to me as the
 birth place of many new ideas in min. 1 ing, milling and metallurgy. It has been said by a writer for a Boston mining publication that the plants of the Clifton-Morenci companies were "scrap heaps." But I am con-
 vinced that these same scrap heaps are doing better all-'round work than many plant of the greatest modern ity.
 Continuing his interview MT. Dins- more said:
 "I Idon't know much about your mining here, because on this trip did not intend going underground anywhere, putting that job off until another visit. But I did go down in- to the Coronado with MT. Scotland land Archie Morrison was along to add to the pleasure of a most pleas ant day) and while underground I saw some things most enlightening. And the ore bodies-it was something marvellous. One ore body I saw on the 200, now partially worked out, that down on a basis of F feet of ore 70 a ton, you have in this single block l20,0O0 tons. It was good ore too. This ore mined itself. That is, MT. Scotland cut around on all sides of this block and then let it alone for a long time, when it just naturally, be- cause of weight and gravity, settled and as it did so was broken up, thus eliminating all necessity for mining by stoping or other method. Chutes were put in and the ore picked and shoveled into these and thence into cars and thence to the shaft and the surface; this is mining on big scale and with the utmost economy. Just beyond this is shrinkage stope that at one time contained 100000 tons. They stopped mining here in June 1907 and have been drawing from it ever since and it will be another six months before the ore is exhausted. Every D feet there is chute, and as the ore will naturally flow from the top, leaving a quantity at the bot tom-back, chutes were run in at sim liar intervals at the back of the stope and ore drawn simultaneously from both sides. Ia the last stnpe on this level the square set system of mining is used. A stope 50 to 75 feet in length is opened on the vein and the ore broken in horizontal slices l5 it. nigh. When one slice is completed the stope is cleaned of ore and waste filling is run in as in mining the Met calf oxidized ores. To allow of the stope being worked continuously two waste raises are employed; this al lows one part of the stope to be filled while the other is being worked. With the exception ot the roadway, chutes, and ladderways, no mbering is employed. The expense of break ing and leveling waste for each slice and the exposing of uuskilled labor CTS under high roof, constitutes a vital objection to this system. These defects are overcome by a system de Yised by MT. Scotland in which the shovelers work outside of the stope, the miner is kept so close to the back of ore as to allow constant scrutiny. The handling of waste is reduced to a minimum. On another level they use the pillar and shrinkage system; at another the slicing, and so on, every method known to good mining being employed, depending upon the work to be done, the nature of the ground and of the ore.
 ''I must revert to the rugged na- ture of the countrywide towering mountains and the thread like in cliues employed for the transport of men, supplies and ore. A very inter esting school ma'am of MorenCi told me that the Coronado incline was equal to reading Dante's inferno after midnight. She said she went up once and ie so happened that there was no one to accompany her. all of her party having gone up ah9ad. She got on car unaware of this and when she found she was alone the car was in motion. First she thought she would jump off, but she then re- considered, believing it would be best to just fall off whenever the car jump ed the track, and in that way she might not be so badly hurt as she might if she jumped-and she reach ed the top in perfect safety. It is quite an incline, for a fact, as are the others at Metcalf, as well as the Longfellow incline, which runs for