but I am convinced that this is not the case (although it is certain that both streams mentioned did at one time flow at as high, and even considerably higher, levels). The materials that so largely distinguish these bench or hillside gravels (placers) are in greater part rounded bowlders or cobbles of white quartz, with a marked deficiency of the fragmented schists and slates which make pay dirt and bed rock in the course of the streams below. [Footnote 2: Prof. Israel Russell has made the interesting observation that orographic movement may now be taking place in the region of the middle Yukon, about the Lower Ramparts, with the uplifting of a mountain range athwart the river; on this supposition he seeks an explanation for the detail of the Yukon lowlands.] _Per contra_, the creek claims of Eldorado and Bonanza contain, as a rule, only an insignificant quantity of the rounded quartz bowlders, while almost everywhere where excavations have been made the body and substance of the output are the flattened and discoid parts of the mother-rock of most of the region--quartzitic, micaceous, hornblendic, and chloritic schists, and with them a less quantity of gneissic and dioritic rock. The high quartz-capped knob to which reference has already been made as marking the water parting of French, Nine Mile, and Adams Creeks, has large quartz masses entering into its composition, whether as bosses, dikes, or veins, and to them, or rather their wasted parts, must we look for the source which has so generously supplied the materials of the French-Adams Hills benches. There has been a bad break-up in this quarter, and the materials resulting from it have been swept into the confluence (delta) of the two streams which define the main valleys. Furthermore, the descending arcuate contour lines which are so well marked by terrace slopes on that face of French Hill which is turned to the corner of Eldorado and French Gulch, show plainly the receding course, in the direction of south, of French Creek (Gulch). On the hill slopes south of the position which it now occupies there is none of that deposit which lies to the north of it; the riches of French Hill are delimited by French Gulch, and even in the gulch itself there is nothing that can be compared with what is found on the heights. Again, on the side of Eldorado opposite to French and Gold Hills there is the same deficiency as regards the characteristic bench deposits, and this also holds true with the Bonanza opposite Skookum and Adams Hills. If these high-level deposits were in fact the ancient waste of the Eldorado and Bonanza, we should naturally expect to find at least "outliers" on the less favored bank of the streams, and surely in the case of the Eldorado former evidence of this deposition ought to be had on the hillsides, similarly contoured to those of the north, which lie south of and immediately adjoining French Gulch.