OMGOX.
In physical and climatic conditions the State of Oregon is divided by the Cascade range into two distinct and strongly contrasted portions. Western Oregon is a rugged and mountainous belt having a very moist climate. Eastern Oregon, which occupies two-thirds of the area of the State, is mostly broad desert valleys with a few mountain ranges toward the eastern border, and has the dry climate peculiar to the interior of the Eocky Mountain region. Of the geology of the State only a few broad general features are known. The rugged region of western Oregon contains representatives of the auriferous slates of the Sierra Nevada, and is supposed to form the geological continuation of that range. The higher portion of the Cascade range is formed of recent lavas, which spread out in places to a considerable distance over the horizontal tertiary beds that fill the broad plains and valleys at its eastern base. The most important mountain range of eastern Oregon, the Blue mountains, is reported to contain Triassic and Jurassic limestones, like corresponding ranges in western Nevada, while granites and metamorphic rocks form the basement complex, underlying all more recent sediments.
The precious metal output of the State is mainly in gold, silver having been produced in comparatively insignificant amount, except at the close of the decade when several important silver mines were opened in the eastern portion of the State, but which have since been closed down.
The gold placers of western Oregon are from the configuration of the country necessarily much smaller than those of California, yet in earlier times they afforded the major part of the gold product of tlfe State. They are still worked on a small scale by individual miners, largely Chinese, and to some extent by hydraulic mining. An interesting variety of placer mine is afforded by the beach sands which result from the disintegration of the gold-bearing rocks along the Oregon coast. A small amount of placer gold is derived from them,
