COAST RANGE GRAVELS. 299 
from the work. These have reference to the manner in which the gold is 
distributed in the detritus with which it is connected. The particles of the 
precious metal may be quite uniformly scattered through the mass, or they 
may be almost entirely concentrated within a narrow vertical range: in the 
latter case the pay-gravel or pay-streak is pretty sure to be on or near the sur- 
face of the bed-rock ; or the lower portions of the detrital mass may be much 
richer than the strata above, and yet the latter capable of being washed with 
profit by the hydraulic method, under favorable circumstances, even when the 
richer portions below have been previously worked out by drifting. Still an- 
other matter has often to be weighed in connection with gravel mining. The 
body of gravel may be heavy and rich in gold, but capped with volcanic mate- 
rials which are of too solid a character to be capable of being washed away — 
or “ cut,” as it is usually called — by the jet from the pipes, even with the use 
of powder, in which case the hydraulic method cannot be used at all; or, on 
the other hand, the capping, whether of volcanic material, which would yield 
to the force of the water, or of non-auriferous pipe-clay or gravel, may be 
too heavy to be capable of being handled without incurring more expense 
than the yield of the auriferous stratum beneath will justify. 
Considering the above-mentioned circumstances influencing the develop- 
ment of the gravel-mining business, we may expect to find, and do find, a 
variety of methods employed, corresponding with the various conditions 
specified. Further on in this chapter some of the economical considerations 
connected with the hydraulic method, as well as the other kinds of 
mining employed in the gravel regions, will be briefly set forth. At present, 
it most concerns us to notice the fact that the gravel deposits of the west 
slope of the Sierra Nevada almost always contain some gold, and that there are 
~ comparatively few localities where they have not been “ prospected” to some 
extent; so that, on the whole, their distribution is pretty well understood. 
- The occurrence of bodies of gravel of considerable size in the Coast 
Ranges has already been alluded to.* Some of these, in the southern part 
of the State have, in former years, been worked for gold to some extent; but 
it is not known to the writer that any of them are at the present time. By 
far the larger portion of the Coast Range gravels may without hesitation be 
set down as nearly or quite destitute of gold, as the activity with which pros- 
pecting has been carried on during the past thirty years is sufficient assur- 
ance that but little of value can possibly have escaped the notice of the 
* See ante, p. 22, 23. 
