But as the bottom and edges of streams are rough and uneven, very frequent obstructions to water occur. Places so obstructed, are the eddies or partial eddies, so commonly observable in streams of running water.
If an observer stands on the bank of a creek, during a time of high water, where there is much irregularity and unevenness of its bottom, he will see in some places, that the water is nearly motionless—in others, a whirling round of the water,—in others, a retrograde or up stream motion. Under all the circumstances of these several appearances of the water, those places that are the most quiet, approach nearest to the most perfect eddies.
Wherever a bend in a creek occurs, the water, by an opposing bank, is forcd to take a new direction, passing downward, along on its inclind, though uneven bottom. The opposing bank stops a portion of the flowing waters, and causes them to turn back, along the shore of the creek, producing, thereby,—a section of inactive waters, between those of the downward and those of the upward course.
Again, if a lateral stream of water flows into a creek, similar or nearly so in magnitude, the two partially opposing currents form an eddy in the upper angle of the two, and an eddy of less magnitude, is also formd in the angle of the two, on the lower side of the lateral stream.
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.
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.