Editorial Comment. 45 
situation, the various views that have been expressed by geolo- 
gists since the examination and report of Dr. C. T. Jackson in 
1848. They arrixe at the final result and state their conclusion 
thus: " That the Keweenaw series is much older than the east- 
ern (Potsdam) sandstone; that it was upturned, faulted along 
the escarpment, and much eroded before the deposition of the 
eastern sandstone; that the latter was laid down unconformably 
against and upon the former, and that subsequently minor fault- 
ing along the old line ensued, disturbing the contact edge of the 
sandstone." 
The description of the shore line of the Bete Grise bay ac- 
cords with that given by former observers, in all the essential 
particulars. The eastern sandstone contains some bands of red 
shale and red pebbly conglomerate. The chief point to note 
here in discriminating the evidence for and against the greater age 
of the trap and conglomerate series, is the fact that J. W. Foster 
in 1849 makes the brick-red pebbly conglomerate identical with 
some seei on the northern slope of Keweenaw point, and hence 
of the age of the copper-bearing series. He distinctly states 
that the eastern sandstone "abuts against a bed of brick-red 
conglomerate;" this fact goes to show, if a fact, that the sandstone 
interbedded and conformable with this pebbly conglomerate, 
is not a part of the eastern sandstone of the region; and that no 
conclusions, touching that sandstone, can be based upon its rela- 
tions to the trap and melaphyr. Mr. Foster also states that the 
high southern dip along the shore of this bay is due to an anti- 
clinal formed bv the forcible ejection of the trap rock through 
a fissure of the earlier sandstone. 
However, Messrs. Irving and Chamberlin seem to show sat- 
isfactorily, by the pebbles of melaphyr contained in the pebbly 
conglomerate, both that the conglomerate is unconformable on 
the trap rock, and that all the light-colored sandstone seen here 
is of the same age as the red and pebbly beds. The prevailing 
dip being to the south, and away from the melaphyr and diabase 
hills lying further north, the natural conclusion is that the sand- 
stone is of later date than the melaphyr and diabase. 
At the Wall ravine however, is a series of facts, as illus- 
trated by Messrs. Irving and Chamberlin, which require on 
their face, exactly the reverse interpretation. This locality is 
