394 0. Whittlesey—Pre-Glacial Channel of Eagle River. 
The general direction of the glacial striae on Point Keweenaw 
is from the northeast towards the southwest, and therefore 
within about 25° of a perpendicular to the course of the ancient 
channel of Eagle River, at the Phoenix Mine. In moving 
across the old channel the pressure of the ice mass was such 
that the drift materials were made nearly as compact as rock. 
Glaciated surfaces in the vicinity reach upward from the lake 
level to the top of the semi-mountainous range, an elevation of 
700 to 1,000 feet, from which it appears that the ice had a very 
considerable thickness. : 
At the point where the miners happened to strike the rock 
floor of this old channel, there was a steep rise in the roc 
bottom, on the right hand side; and they followed awhile along 
the foot of this slope. The boulders that were found in the 
‘“‘hard pan” were held firmly in it, either by pressure or by 
cement, and were of various kinds of rock, as sandstone, trap, 
granite, porphyry, etc., the same as are common in the ake 
Superior drift-deposits. These were very much water-worl. 
On the back of the vein, and in its vicinity, there were rounded 
lumps, and grains of native copper, of all sizes, some of them 
still bright and shining. 
hese discoveries tempted them on; and turning to the left 
or to the north, they followed along the vein. They were evi 
dently in the bed of an ancient stream, the predecessor of the 
Eagle River, as it existed at some remote period. Along A 
lowest part of this lay the vein which perhaps determined the 
course of the stream. For about thirty feet the floor was not 
found to be very uneven, but, as it here sunk below drainage 
level, a branch gallery, D, was started obliquely to the right 
At 27 feet, in this direction, the gallery being entirely 10 we 
a rock face was struck. The gallery, thus made, proved to 
the diameter of a circular cavity, (marked “Basin No. 1, 0° 
the map) which was found to be 17 feet deep. : d 
The miners then followed around the rim of the basin, a0¢ 
also descended nearly to its bottom, taking out large quant: 
ties of loose copper and copper-bearing gravel. One mass, iro” 
the level, near the basin, weighed 1,760 pounds. This basia 
appears to be a gigantic pot-hole. 
On the northwestern quarter of the basin, a narrow fissure 
was discovered, which represented the vein; and along this the 
miners worked to the distance of 174 feet from winze A (se 
prgt which had already been sunk on the vein. The bottom 
of the gallery in this direction was not very uneven, 8 
descended but slightly to the north. The earth of the gallery 
sides remain rm; but on the 16th of November, 1& 2 
stream of water was struck which discouraged the superinte? 
dent, and the work was abandoned. 
