PREGLACIAL GRAVELS ON THE QUARTZITE RANGE 
NEAR BARABOO, WIS. 
WITH SUGGESTIONS AS TO THEIR CORRELATION. 
AT a number of points on the east bluff of Devil’s Lake, and 
about half a mile from it, at an elevation of 1560 to 1580 feet, 
A. T., there are traces of gravel differing radically from any 
other surface formation known in this part of the State. These 
traces are, in general, very meager, consisting of scattering 
pebbles only. They may be seen along the crest of the south 
face of the east bluff for a distance of 80 rods or more, and along 
the path leading down from the summit of the bluff, in the 
vicinity of the Devil’s Doorway. This path leads over the talus 
slope of the quartzite range, and the well-rounded pebbles of 
chert, flint and light-colored quartz are in striking contrast with 
the purple quartzite blocks over and among which the path- 
way leads. The pebbles along the path are clearly in secondary 
positions, having come down from the crest above. 
There is a single point, a few rods north of the upper end of 
he path referred to, where the same sort of gravel may be seen 
to exist in considerable quantity. The crest of the ridge is here 
somewhat broad and flat. On its surface a well was dug some 
years since, and at the site of the excavation, the gravel was 
found to have a depth of 16 feet, and to rest eucady upon the 
firm surface of the quartzite. 
The gravel thrown out in the digging referred to has been 
subjected to the weathering of many years, but its character 
does not appear to have been perceptibly modified. It is made 
up wholly of quartzose material, consisting principally of chert, 
flint, vein-quartz, and silicified fossils. A glance suffices to show 
that the larger part of it was derived from limestone formations. 
In size, the constituents of the gravel range from tiny pebbles to 
cobbles, three, four, and even five inches in diameter. The 
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