Bisbee daily review., 1904-03-10
Warren nlining District
Geology and Veins
 Tombstone, Ariz.,
SOME NOTEWORTHY FACTS RE,
 oARpiNo THAT DISTRICT.
Paper Read Before the American h. stitute of Mining Engineers by Will jam P. Blake, F. G. S., Director of the Arizona School Of Mines-Ar.i- cie Presents Interesting Data.

the Arizona School Of Mines-Ar.i
 cie Presents interesting Data.
 The following article, read befor, the last meeting of the American In stitute of Mining Engineers, was pre- pared by William P. Blake. F. G. s. director of the Arizona School O Mines. It presents data in regard tt Tombstone, it's mines and geology O that district, that are interesting anC should receive the perusal of those following the mining industry in tho great southwestern mining territory:
 In former paper, read at the Wash ington meeting of the institute, Feb truary, 1881, l presented a general re view of the geology and veins ct Tombstone as then developed. Con siderable additions have been made .c our knowledge of the ore deposits {, since that cate. nearly all the mines having been worked down to the gen eral water level of the district. This water was bar to further progress ir depth, and costly pumps were erected iat the Grand Central mine and at the lContention. By the united action of these pumps the water was gradually lowered. not only in these two mines but in all the important mines in the district. Pending a consolidation of interests, or an equitable distribution iof the cost of unwatering, both pump ing plants were destroyed by fire, and the mines were closed down and re- maine6 practically idle for twenty Iyears, until, in 1902, by the efforts of Hon. F. B. Gage of Arizona, the desired consolidation of the mining interests was effected and an organization was formed under which the mines have been reopened, with the intention of working them to a greater depth.
 A new and large four-compartment shalt has been sunk to the 6O0-foot level of the Contention mine, or just above the water. 569 feet below the collar of the shaft At this level DOW eiful pumps have been placed, and
 
 foot level, where other pumps have been installed and will throw water to the surface.
 The pumps are from the Prescott Steam Pump company of Milwaukee. They are of the direct-acting type. triple expansion, with steam cylinders in pairs of 39-inch, 23-inch and 15-inch in diameter. The diameter of the water piunger is 13 inches; stroke, 2i inches
 Tombstone is now directly connect ed by rail with Fairbanks, in the San Pedro valley, and with the overland trunk lines.
 Some of the more important devel- opments and additions to our knowl- edge of the ore deposits may be briefly enumerated:
 l. The West Side vein has been ex- tensively worked and has produced a large amount of ore. not only from the lateral deposits n limestone, known as flats" of blanket deposits" but from ore bodies on the plane of the vein to a depth of about 800 feet, or to the water level.
 2 It is ascertained that the latere: deposits, flats, or blanket deposits, ex- tending from the plane Of the vein, or kde, and generally into the beds of limestone, follow the crests of the anticlinal folds rather than the cyn- clines or other portions of the beds.
 3. Several such cre-laden anticlinal folds" or saddles" CT rolls" as they are locally known. have been 6evel. oped, and quantities of valuable ore have been taken from them.
 4. The blanket deposits have great extension compared with their width. and follow the crests of the folds in their downward pitch away from the intersecting lodes. Several such 6e- pcsits have been followed from the West Side vein nearly to the water level.
 5. The blanket deposits appear to have been reinforced, or enriched, by each successive crevice. or vein, cross ing them or the limestone anticlines.
 6. The former observation and statement, that the heaviest or largest ore bodies are found on the lower or down-hill side of the intersection of the Dlicated rocks with the crevices or lcdes, is sustained and exemplified.
 2. Much light has been thrown up- on the question of the origin of the maDganiferous ores of the Lucky Cuss. the Luck Sure. the Knoxville and other mines. by the discovery of a mass of manganese sulpbide the mineral species alabandite in the midst of the limestone upon vne of the low CT levels of the Lucky Cuss mine, near the contact of the limestone with the granodiorite. There is little reason to doubt that included masses CT kid neys of alabandite in the limestone are the source, by decomposition and precipitation. of the manganiferous ores of the pipes or chimneys SO com mon from the surface downwards. These deposits. by their form and re- lation to the limestone. indicate their