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THE AUEIFEEOUS GEAVELS OF THE SIEEEA NEVADA. 



years. The hydraulic method of attacking the gravel deposits has become 

 more and more universal of late years, and is now almost the only one em- 

 ployed, ordinary placer mining with portable implements for washing having 

 been almost exclusively relegated to the Chinese, while tunnel mining is also 

 practised on a much less extensive scale than formerly. But in hydraulic 

 mining, with sluices many hundred feet in length, nothing can be seen of 

 what the gravel may contain of human or other remains, unless under very 

 exceptional circumstances. The coarser, larger implements, if sufficiently 

 strong to endure the wear and tear of the sluice, would be carried down and 

 deposited far away in the tailings and then speedily covered by other ma- 

 terials. The finer and more delicate portions, such as bones, are ground to 

 powder between the cobble-stones and are lost forever. By the tunnel 

 method some portion of the material excavated stands a chance of bein< 



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examined ; or, at least, of being for a while in such a position that it could 

 be inspected if there were any one present who had the curiosity to do it. 

 Hence most of our evidence of the former existence of man during the 

 gravel period comes from a region of former tunnel mining on a large scale, 

 and is, much of it, of ancient date, because this region is pretty nearly 

 worked out and abandoned. That evidence greatly exceeding in fulness 

 and value any that has heretofore been obtained may yet be secured is 

 certainly possible, if not probable. It is not necessary, however, to specu- 

 late on what may happen in the future, but rather to set forth what is 

 already known. 



It will be observed by the reader of the following pages that the bulk of 

 the evidence presented is that furnished by the miners themselves, some- 

 times supported by the actual presence of the objects found, at other times 

 without such support, there being only the bare statement of a former find. 

 That the miners themselves should be, in most cases, the persons furnishing 

 the evidence is too natural a circumstance to need comment. Their state- 

 ments have to be taken — as already suggested when speaking of the occur- 

 rence of animal remains in the gravel — for what they are worth, balanced 

 against each other, and the most probable result accepted. A long chain of 

 circumstantial evidence is frequently more convincing than a single state- 

 ment of an eye-witness. It might be asked, Why should not the writer, or 

 one of his assistants, have been on the spot when some of these discoveries 

 were made, or have taken with his own hands some one of the objects men- 

 tioned from its original resting-place ? The answer to this is, that such finds 



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