As so many and various opinions of the tilted condition of primary stratified rocks have been advancd among the visitants of the gold district of California, a few conflicting opinions may serve in some degree to satisfy the mind of the curious.
It is the belief of some, that rocks cannot have become tilted without the expansive powr of volcanic agency. Hence, on viewing the country around, they imagine they see successions of craters, formd all over the western declivity of the Neveda mountains, and in some places, profusions of scoria bestrewing the ground. For my own part, I must confess that I have seen nothing in my ramblings to justify a belief that volcanic agency any where has existed so as to produce the present appearance of those rocks.
Those persons imagining volcanic agency in those parts, are not aware that intense heat destroys stratification, for in the middle of the craters of some of their imaginary volcanoes, the stratification is as perfect as in any other portion of the tilted district, and they are not apprizd that in such case a discrepancy must therefore exist.
After the tilting of those rocks had occurd, it would not be improbable, with such an enormous crust resting entirely upon a liquid, molten nucleus, that many undulations in it should occur, and in many instances the crust should become weakend and even sunderd apart by the severe strain. Into fissures so formd, granite, sandstone and conglomerated rocks, may have subsequently been intruded, presenting, therefore, to persons unacquainted with such rocks, the appearances of craters, scoria, &c. In some parts of New England, primary stratified rocks are tilted up confusedly, having no regular line of strike. In some cases, the dynamics employd may have been volcanic, or they may have been paroxysmal, acting from time to time, till those rocks were thrown into their present condition. But tilted rocks that have a regular line of strike, must have a regular agency to place them in such condition. Hence, then, considering the perfect parallelism of the tilted rocks of Golden California with the mountain axis, it seems to follow, that an exceedingly slow and regular movement of the tilting of those rocks must have occurd.