Geology of the Lake Superior Region. — Winchell. 13 
made the cause of serious error. It is not always under the 
lead of the discoverers that these new keys are misused, but 
their followers and imitators are prone to not only adopt the 
new ideas but to apply them to the solution of problems and 
to the funded discovery of other ideas to which the}' have no 
relation. This tendency once«started b}' an influential geol- 
ogist is carried much farther by otliers, and still farther by 
their successors until the bad consequences become so evident 
that the}" are finallj' detected and their cause is discovered. 
Then commences a swing of the pendulum in the opposite di- 
rection, with perhaps equal exaggeration and equall}' serious 
errors. The later errors, however, are never duplicates of the 
old mistakes. They are on another plane, and their effects 
are less broad in scope though not less profound in originality 
and importance. B}" the amount of advance which separates 
the later plane from the arena, on which the earlier geologists 
operated, is the progress of the science measured, from gener- 
ation to generation as the pendulum of opinion swings from 
extreme to extreme. Like a ship which makes headwaj^ by 
tacking into the wind, does geolog}'' constantly shift and con- 
stantl}" advance, though rareh' or never straight ahead. 
The Wisconsin geologicivl survey served as one of the turn- 
ing points in the progressive examination of the geology of 
the Lake Superior region. Almost everything before that, so 
far as relates to these formations, had been substantiall}' in 
accord with itself — at least there were few dissentients from 
the leading classification which h:id been advanced in the 
middle and earl}' in the latter half of the century. Before 
noticing the new ideas approved by the corps of the AViscon- 
sin survey, it will be best to consider succinctly the ideas 
that were, prevalent prior to that survey. 
The officers of the C^anadian geological survey were among 
the first to put forth generalizations upon the stratigraphy of 
the Lake Superior region. The tragic early death of Dr. 
Douglass Hughton, by drowning, cut short for many years the 
voice which American geologists south of the international 
boundary might have had in forming geological opinion on 
these rocks. He shared the views of Dr. E. p:mmons, and 
many of the specimens collected by his field parties were la- 
belled by him and referred to the Taconic system. Thus la- 
