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period, presents in the Cascade Range, which divides it into east and west halves, the same general features found south of the Columbia River. It is noticeable, however, that there is a great thickness of gravel-beds and sandy deposits on the north side of this boundary, not to be found south of it. All along Puget Sound to the Fuca Strait this is apparent, but when we come to the archipelago in the mouth of the strait, and north for some distance, the upheavals are basaltic, with rounded, domelike peaks.

The coast of the Olympic peninsula bordering on the strait is also basaltic, and this formation extends to and through the foot-hills of the Coast Range to Mount Olympus. Here the formation changes to slate, sandstone, gravel, and marl.* Granite in place occurs rarely, but lime deposits are found in the streams, indicating the presence of lime-rock or marble somewhere in their channels. The stratification is very much tilted, and therefore displayed in the canons as orderly as books upon a shelf. The secrets of nature are revealed as plainly as in East Oregon, and give evidence of the comparative youth of these mountains. If other proofs were wanted, they are found in their sharp peaks and jagged sides, where other precipices of rock are found from one thousand to two thousand feet high. Even the beds of the streams are little worn. Where they run through deep canons, it is where they have found and followed fissures. Cascades are frequent, often plunging over soft slate rock. Thin veins of quartz are seen in the slate and sandstone. Granite boulders are found which appear to be glacial, but there is no evidence of volcanic overflow from any part of this range.

A great deal of interest has been recently exhibited in the exploration of the Olympic Range, several expeditions being in the field this present summer. It does not seem probable that anything further will be learned concerning the general geological features than is already known, but it is hoped to discover some useful minerals. Indeed, since the explorations of a year ago, a copper-mine has been opened which promises well. Of this I shall speak more particularly in another place.

spent the winter of 1889-90 in exploring among the Olympic Mountains.
 * This statement is made by Charles A. Barnes, geologist of a party which