226 Blake—Progress of Geological Surveys in Wisconsin. 
rection of the deposits, upon a scale of one-fourth of an inch 
to the mile, but exhibiting the relative number and the direc¬ 
tion of the known ore-bearing crevices by means of small lines, 
the first attempt, perhaps, to represent the Surface arrange¬ 
ment of the diggings, and the general direction of the bodies of 
ore. 
In addition to the descriptions in detail of the various form¬ 
ations and of the veins or deposits of the ores of lead and zinc, 
he notes particularly, under a general dip of the strata to 
the south, local inequalities in the* stratification at various 
points, indicative of extraordinary elevations of the strata and 
the existence of faults or breaks in the formations. Five at 
least of such faults are described in the region of the Peca- 
tonica valley, of Fever river, of the Platte and on Grant river. 
In regard to the extent downwards of the mineral deposits, 
he favored the view of many that the viens could be traced, with 
some interruption, from the Upper Magnesian Limestone down¬ 
wards to and into the Lower Magnesian. On p. 67 he says: — 
“ I have not yet had time to explore the country occupied by the 
Lower Magnesian to any extent, and have visited no other dig¬ 
ging in that rock bat those in the vicinity of Blue river, 
known as Oleking’s Diggings. These, however, furnish most 
satisfactory evidence that the mineral occurs in that* rock at 
the proper openings in as large masses and arranged as regu¬ 
larly as in the Upper Magnesian. ” * * “After examining this 
locality, I could not doubt that the Lower Magnesian is a good 
mineral-bearing rock. I have thus been able to trace the min¬ 
eral in a series of crevices and openings from the summit of the 
Upper Magnesian to the depth of 60-70 feet in the Lower Mag¬ 
nesian, and have found all the different beds of limestone good 
mineral-bearing rocks, each with one or more openings, besides 
vertical or pitching sheets or veins. ’ ’ He notes that the ar¬ 
rangement appears to be analagous to that of the lead mines 
in the north of England where the veins traverse different 
beds of limestone separated by other beds, the mineralization 
being confined chiefly to the limestone. 
In regard to the arrangement or distribution of the deposits, 
their grouping and direction, he was convinced that there is a 
