MATRICES OF VEINS. 



law of gravity, which distributes the pieces as they have 

 been hurled or washed down from the parent rock with a 

 certain amount of regularity the larger and least weather- 

 beaten ones being nearest the lode he can leastways 

 observe at what point up the slope the " float " rock ceases 

 to be seen ; then he may sink a ten-feet-deep pit, or else 

 drive a crosscut to strike the " body " of that which he is in 

 search of. 



Before commencing this, he must take note of the slope 

 on which the " likely " broken away rocks repose, because 



\ 



MX 



FIG. 1. ILLUSTBATION OF A DEPOSIT PDESUINO A CUEVILIKEAB COURSE. 



0, outcrop ; the deposit dipping 60. A shaft sunk at A would cut the deposit at 

 y inbtead of X, as supposed. 



judgment may tell him that the parent rock is not directly 

 under his feet, but rather to the right or left, according to 

 the amount of inclination of the hill-side. Much unneces- 

 sary labour is often performed through not taking account 

 of this, as one naturally imagines that the lode is just 

 underneath the line where the greatest amount of "float" 

 occurs, whereas it may in reality be several yards distant, 

 probably on the ridge just a little way off, but decidedly not 

 on the other side of it. 



Sometimes, as is the case with the Transvaal conglomerate, 

 the direction of a deposit near the outcrop may alter con- 



