RUBIDGE — OX METALLIFEROUS SADDLES. 
283 
in fig. 3. The points a and c, were not tkree feet apart ; the line 
f. g., about an inch thick, was micaceous rock ^vith large crystals 
of felspar. The richest deposits of ore seemed to me to occur at 
Line of Stxike. 
Fig. 3.— Koperberg. 
h i, direction of the metallic axis ; k I, strike of the rocks ; dip towards h i. 
spots on the saddles or axes where one or more of these twists met 
them. There was generally no metal in the twists. The axes too 
were traceable for miles through the country, but were only metalli- 
ferous, to any considerable extent, at inteirals. Thus, I believe the 
mines of Spriugbok Vontein and Koperberg were on the same run — 
a good section of which was visible on the side of a ravine crossing 
it nearly at right angles near Koperberg. This showed that these 
disturbances were not produced by, nor essentially connected with, 
granite. The meeting of a twist with the saddle of Koperberg I 
have mentioned. I believe more than one crossed that of Springbok 
Vontein, though the surface was so decomposed and so scarred and 
fissured in various directions that it was impossible to make it out 
clearly. This mine had not been worked to any great depth when 
I visited it. The observations on the succession of ores, though I 
believe it applies equally to this, was made at Concordia and other 
places. 
At Nababeel, a spot which has not produced so much ore as its 
appearance promised, was observed the structure shown in fig. 4. 
