MINES LINDEN DISTRICT. 727 



blende mixed with lead ore and associate minerals, of from one to three feet thick. At- 

 tention is here called to the remarkable curvature of the sheets or pitches. Beginning 

 at the well shaft, they take a northeasterly course, curving around to a northwesterly 

 one at the engine shaft, and finally to a westerly one at the west pump shaft. But one 

 parallel case is known in the entire Lead region. It is the Watkins range of the Dodge- 

 ville district, situated in the same opening, and worked' for the same ore. 



Although the blende usually occurs in a large sheet, yet it is frequently connected 

 with two or three parallel smaller ones by veins or " pitches." The sheet often contains 

 detached pieces of the wall or cap-rock, of various sizes, completely surrounded by ore. 

 Large pockets occur in the bed, lined with very handsome crystals of calcite, one of 

 which, recently removed from the mine, measures five feet by two. 



Another peculiarity noticed was the fin ,ing of several pieces weighing from one to 

 five pounds, composed of wall-rock and ore, which were rounded and worn smooth, re- 

 sembling small drift bowlders. They were found in the lower pipe-clay opening, and 

 had probably been detached from the wall, at its junction with the ore. They must have 

 undergone considerable erosion and transportation, or movement, by subterranean cur- 

 rents of water. 



The workings in the vicinity of the eng'ne shaft were first, examined. They extend 

 in a westerly direction a distance of 1,300 feet, and have been worked to a width of 45 

 feet, leaving a sheet of blende on the northern side from one to three feet thick. It has 

 been proved by a cross cut to connect through to the north pitch, a distance of 180 feet. 

 The same sheet has been worked in a southerly direction nearly to the well shaft, a dis- 

 tance of 600 feet, leaving a large sheet of blende on its eastern side. These workings 

 are in the glass- rock opening, and about twenty feet above the St. Peters sandstone. 



The following section of the engine shaft will explain their situation : 



Ft, In. 



Dump rock, clay and soil 15 



Galena limestone 72 6 



Blue limestone 6 6 



Pipe clay 1 



Glassrock 5 



Glass-rock opening (workings) 4 



Buff limestone to bottom of shaft 8 



Buff limestone to St. Peters sandstone 16 



Total 128 00 



The workings at the well shaft were next examined. They are in the Brown-rock 

 division of the Galena limestone, and about 26 feet above the lower workings. As will 

 be seen on reference to the map, the ground is worked in an irregular shape about 300 

 feet long, by 150 feet wide 



It is estimated that $200,000 worth of ore has been taken, in the course of all opera- 

 tions, from this small, irregular piece of ground. It was full of large flat sheets and 

 pitches, and was worked in some places to a height of 20 feet. It now produces 30 tons 

 of zinc ore per week, and considerable lead ore. This is exclusive of the ore raised by 

 numerous miners working here on tribute. 



Fig. 19 illustrates the manner in which the flat and pitching sheets are connected in 

 the ground. It is taken from a point on the south pitch, northeast of the well shaft. 



Two sheets were observed. One, A, coming down through the drift., aaid pitching to 

 the south, and the other coming in from the north en a flat E, making a pitch to D, 

 a second at flat C, and a second pitch at B, through the floor of the drift. At B it is only 

 about three feet distant from the sheet A. It is known from the extension of the 



