When water passes over a reef of rock, that traverses entirely across the stream, like a mill dam, the central waters or current cannot well form an eddy immediately below the reef, on account of its impetuous movement—though laterally, towards the banks, partial quietness of the water may exist.
If an obstacle, as a rock or other body, protrude in the current of a creek, so high that water is forcd around it, instead of running over it, an eddy is formd immediately below it, in magnitude according to the size of the obstacle.
CHAPTER XXI.
Mode of searching for Gold in California.
Rock gold, or that which is disseminated in dust or fine particles amongst quartz rock, being so rare in California, but little attention is paid to searching for it in such situations.
Mode of Searching for the First Variety.
The miner, in prospecting for the first variety, or dry ravine gold, selects a situation where, judging from the appearance of the hills, or the slope of the ravine likely to contain gold, it may be found most abundant. He commences his excavation at the center of the ravine, by digging downward till he arrives in most cases at the rock on which the deposit was made, which varies from 2 to 10 or 15 feet in depth. He then prospects outward toward the hills till he arrives at the line of deposit, in case any deposit there exists.
After having found a lead of gold, he excavates upward and downward the ravine, being careful whilst progressing along, to watch the several meanderings of the lead, which are likely to occur even in very short distances.
The miner never need be long at a loss to determine whether there be gold in the place where he is prospecting. If gold exists only in moderate quantities, the pick will generally detect it by occasionally throwing out into view pieces of gold, even when they are quite small. In digging in dry ravines, the miner, after having arrivd within a few inches of the rock where he expects to find gold, tries the earth by washing some of it. If he finds no gold, all of the earth above this place is thrown away as useless. He then continues to dig downward, trying the dirt at short intervals, till he finds gold in his washings. He then is careful to save and wash all of the remainder that lies above the rock, and even to pick off a few inches from the top of some rocks that are loose and open enough to receive gold in some of their crevices, carefully saving and washing the whole.