318 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [March 8, 



Again, if it be so removed, it is evident that the ice-drifted matter 

 from these hills was never allowed to float far out to sea before it 

 was thrown back against the beach again. To this I would add, 

 that the gold found in what is termed the dry diggings is commonly 

 on or near the western slopes of the hills, and in such places has the 

 appearance of being abraded and water-worn, while a few samples 

 that I have seen of the opposite character were found on eastern 

 slopes, or in otherwise sheltered positions : from which facts it would 

 appear that the abrasion suffered by the gold scattered over these 

 broad districts was effected by the waves of the ocean, under whose 

 action it would be again laid close against the ancient rock. 



Comparison between Drift-workings and Quartz-vein-mining . — 

 When the rage for quartz-gold-mining broke out, it was proposed 

 by some members of our company that we should join in a work of 

 that description. This I opposed, from a conviction that it would 

 not pay so well as the surface-workings. The arguments I made 

 use of were to this effect : — that in whatever superficial debris or 

 . earth gold is found, the lower it be in such soil the richer it is, and 

 always richest next the rock : in gulleys where frequent land-slips 

 have taken place, successive beds containing gold may be found, but 

 the lowest is always the richest : the wealth of the gold is not only 

 in quantity, but likewise in the size of the grains or lumps the de- 

 posits contain, while the opposite order seems to take place in the 

 quartz-veins : the richest mines yet discovered occupy the highest 

 situations, while the same matrix, when traced to lower ground, 

 seems to contain little or no gold. From these facts I inferred that 

 the top of the quartz-veins was the richest, and being the first to 

 disintegrate, it was likewise the first to be deposited in the raAdnes 

 below, and as the waste progressed, the deposits became poorer, 

 until in most situations the later waste contained no gold, and by its 

 continued deposits buried the precious metal deeper below. From 

 the same train of argument, it follows that the deeper we sink into a 

 quartz-vein the less productive and more expensive we shall find it. 



One of the company (my friend, Mr. Allan), to satisfy himself 

 practically, examined every quartz-mine then being worked from 

 Carson's Hill to the Mariposa, and by his inquiries, he could not 

 discover that any increase in richness was found by sinking, but 

 rather the opposite result obtained, and the difficulty of working 

 increased from the increased hardness of the rock, and the minute- 

 ness of the gold requiring more perfect machinery to effect a thorough 

 separation. See also p. 314. 



Chinese Diggings. — Mr, Allan and myself being satisfied that 

 quartz-veins could not be worked profitably, I selected some ground 

 for our joint operations in what is called the Chinese Diggings, which 

 fortunately proved to be rich. The place was of that description 

 known to miners as flat or dry diggings, from being situated on a flat 

 piece of country bordered by hills, and having no running water, 

 so that those working there in the summer season either sunk wells, 

 or carted the earth to the nearest springs they could obtain. The 

 auriferous earth was from 1 to 6' feet in depth, according to its situa- 



