Model of an Arizona Gold Mine 7 



THE LEVELS. When the shaft had been sunk 

 fifty feet a small chamber called a STATION was 

 excavated at the right. From this station a long 

 gallery called a DRIFT was excavated along the length 

 of the vein. A drift differs from other passage ways 

 in mines in that it always runs lengthways of the 

 deposit. 



This drift and the workings connected with it 

 constitute the FIFTY FOOT LEVEL, so called be- 

 cause its drift is fifty feet below the surface. 



When the shaft had been sunk a hundred feet at a 

 point near the base of the model, another station was 

 cut and another drift started. This drift and its 

 workings constitute the HUNDRED FOOT LEVEL. 



On the hundred foot level to the right of the shaft 

 is a gallery running directly into the model. This is a 

 CROSS-CUT, so called because it cuts across the de- 

 posit. This cross-cut runs through the vein and into 

 the country rock behind. It was driven to find out if 

 there was another vein parallel with the one worked. 



From the lower level two shaft-like openings 

 extend downward. From the upper level a similar 

 opening extends down to the left. These are WINZES 

 which were driven where some features of the vein 

 suggested that exploration in this direction might be 

 of value. 



Near the right of the model a vertical, shaft-like 

 opening extends from the lower level to the surface. 

 This is a RAISE, so called because it was excavated 

 from below upwards. The reason for driving it from 

 below is that in mining it is much cheaper to work 

 from below than from above. This raise is lined with 

 CRIBBING, that is, logs built up log-house fashion. 

 The raise has two objects. By providing a second 

 opening to the surface it permits a circulation of air 

 and furnishes much needed ventilation. It is also the 



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