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BULLETIN OF THE LABORATORIES 
the magma in the corroded condition already described. The calcite 
and chlorite date from later periods. 
At this point are a number of trap dykes, but the extreme point 
(Burnt Point?) is made up of granite, which continues to the mouth 
of Riviere de la Vieille. Just southwest of the river are precipitous 
cliffs, 600-800 feet high, made up of the highly metamorphic equivalent 
of the schist. Here at places the granite appears beneath the slate, 
which is unconformable and tortuous, without obvious stratification. 
The granite rises only a few feet above the water’s edge in undulations 
and seems to have thoroughly fused the superincumbent schist at con- 
tact. A few miles further south, toward cape Choyye, the high bluffs 
recede from the shore, leaving the point composed of Keweenaw con- 
glomerate and sandstone, which laps out near the water’s edge at a 
slight inclination. 
No. 1074 is a specimen of the schist taken near the underlying 
granite and is a greenish, irregularly fissile rock, completely checked 
up by joints and so altered and veiny as to act as an aggregate with 
much chlorite. 
No. 1075, taken near cape Choyye, is an irregularly lamellated 
mica schist. The section shows much brown mica and quartz, some 
apatite, magnetite, pyrite, and scattered porphyritic more or less 
quadrangular grains appearing like completely decomposed feldspar. 
Although dip and strike, as taken, were dip 60°, strike S. 10° W., we 
rather incline to believe that this is the same rock as that on the west 
side of the bay, with a strike which might bring it hither. 
Returning to Dog river, we proceeded westward for about six 
miles to near Eagle river, a small trout brook near the western limit of 
the bay. Here are precipitous cliffs nearly 800 feet high. The rock 
here consists of much altered highly crystalline schists, varying from 
green to brown (No. io49-io49a). The mica is largely altered to 
chlorite in the green, while jt is reduced to a powder in the brown and 
mixed with hematite. Both contain very large quantities of calcite, as 
a product of alteration of mica no doubt. These rocks contain much 
quartz. The strike is E.S.E., i. e. much more nearly east than far- 
ther northeast, and the dip only about 45°. Here in many places di- 
orite lies interbedded between the strata of schist. This diorite is 
composed of the same twinned hornblende, mentioned at the east side 
of the harbor, but although it is superficially identical it differs in re- 
taining strong pleochroism. The extinction angle and general appear- 
