i34 



ORIGIN OF THE AMERICAN NEGRO. 



with each other by two tunnels running north and south, one near 

 the west side of the mine and one midway between it and the east 

 margin of the mine. 



From the east and west tunnels offsets are driven to the sur- 

 rounding rock. When near the rock, they are widened into gal- 

 leries, these in turn being stoped on the sides until they meet, and 

 upwards until they break through the blue ground. The fallen 



reef with which the upper 

 part of the mine is filled, 

 sinks and partially fills 

 the open space. The 

 workmen then stand on 

 the fallen reef, and drill 

 the blue ground over- 

 head; as the roof is 

 blasted back the debris 

 follows. When stoping 

 between two tunnels, the 

 blue is stoped up to the 

 debris about midway be- 

 tween the two tunnels. 



The upper levels are 

 worked back in advance 

 of the lower levels, and 

 the works assume the 

 shape of irregular ter- 

 races. The main levels 

 WASHING DIAMONDS. are from 90 to 120 feet 



apart, with intermediate levels every 30 feet. 



Hoisting is done from only one level at a time through the same 

 shaft. By this ingenious method of mining, every portion of blue 

 ground is excavated and raised to the surface, the rubbish on the 

 top gradually sinking down and taking its place. 



The scene below ground in the labyrinth of galleries is be- 

 wildering in its complexity, and is about as little like one's idea of 

 a diamond mine as can well be conceived. Electric light is uni- 



