Nov. 1, 1864.] THE TECHNOLOGIST. 



NEW ALMADBN, CALIFORNIA. 173 



after the ore is brought to the surface and freed by hand-breaking 

 from the superfluous or unproductive rock ; by this arrangement, 

 the company are secured from paying for anything but productive 

 mineral. All the small stuff and dirt formed by the working of the 

 " labours " are also sent to the surface to form the adobes used in charging 

 the furnaces. 



It has often happened, in the history of the mine, during the past 

 fifteen years, that the mine for a time has appeared to be completely 

 exhaused of ore. Such a condition of things has, however, always proved 

 to be but temporary, and may always be avoided by well-directed and 

 energetic exploration. Upon projecting, by a careful survey, irregular 

 and apparently disconnected chambers'of the mine in its former workings 

 in a section, there is easily seen to be a general conformity in the line of 

 direction and mode of occurrence of the productive ore masses. These 

 are found to dip in a direction towards the north, in a plain parallel, for 

 the most part, to the pitch of the hill, but at a somewhat higher angle. 

 An intelligent comprehension of this general mode of structure has 

 always served hitherto iD guiding the mining superintendent in the 

 discovery of new deposits of ore. 



Since the settlement of the famous law-suit, which has so long held 

 the company in a condition of doubt, the new parties, into whose hands 

 the property has now passed, have commenced a series of energetic and 

 well-directed explorations at various points upon the hill, with a view 

 to the discovery of additional deposits of ore. At one of these new 

 openings, distant, at least, 500 feet from the limit of the old workings, 

 and not more than 200 feet from the summit of the hill, a deposit of the 

 richest description of the softer kind of cinnabar has been discovered, 

 which, so far as hitherto explored, has a linear extent of at least 70 or 80 

 feet, and, in point of richness, has never been surpassed by any similar 

 discovery in the past history of the mine. A charge of 101,000 pounds, 

 of which 70,000 were composed of this rich ore, 31,000 of " granza," or 

 ordinary ore, 48,000 pounds or adobes, worth 4 per cent., making a total 

 charge of 105,800 pounds, yielding, on the day of our visit, 460 flasks of 

 mercury, at 76^ pounds to the flask. This yield is almost without 

 parallel in the history of the mine. The only preparation which the 

 ores undergo, preparatory to reduction, consists of hand-breaking, or 

 " cobbing," for the removal of the unproductive rock. 



The small ores and dirt hoisted from the mine are made into 

 "adobes" or sun-dried bricks, sufficient clay for the purpose being 

 associated with the ore. The object of these " adobes " is to build up 

 the mouths of the furnaces to sustain the load of richer ores. No flux 

 is employed, there being sufficient lime associated with the ores to aid 

 the decomposition of the sulphurets. 



The furnaces are built entirely of brick, in dimensions capable of 

 holding from 60,000 to 110,000 pounds, according to the character of 

 the ores employed. The chambers are fired from a lateral furnace, fed 



