MINES HAZEL GREEN DISTRICT. 705 



it continuously ever since. Its total completed length is now about four thousand feet. 



It is a feature of this ground that it is traversed by several bars or belts of ground 

 which are very hard and impervious to water. As soon as the level is driven through 

 one of them, it unwaters the ground in all directions to the next bar. 



Sometime in the year 1871, one of those bars was reached which was so hard that blast- 

 ing with powder made but little impression on it. As an experiment, nitro-glycerme 

 was tried and gave the greatest satisfaction, so much indeed that a factory has been es- 

 tablished here, and it is gradually being introduced into the mines. It is at present 

 used in Dubuque, Galena, New Diggings and several other places. It was at first re- 

 garded with some dislike and distrust by the miners, but this prejudice is fast being 

 overcome, and nitro-glycerine or some of its compounds will probably supplant gun- 

 powder in the mines at no distant day. The factory at Hazel Green produced, during 

 the first three years, about three thousand pounds of nitro-glycerine, and the demand is 

 steadily increasing. 



On account of the position of the bars, it was found necessary to make three branches 

 to the level, one of which is now completed and is gradually draining the western part 

 of the ground. The northern branch when completed will undoubtedly unwater.the 

 rest of the ground. 



This level is an evidence of what can be done by scientific mining, when carried on 

 persistently and systematically, with sufficient capital, applied with foresight and saga- 

 city. It has cost the company twelve years of time and about $100,000. Its results are, 

 that it has already repaid the outlay of capital by the ore raised from the ground un- 

 watered by it, which would otherwise have been inaccessible. When completed, it will 

 unwater the ground 135 feet below the natural water level on the ridge It furnishes 

 employment to about 80 miners during the mining season, which without it, would 

 hardly exceed half a dozen. 



Quite a large and clear stream of water is discharged from the niouth of the level, 

 and is at present used to operate a furnace and three wash-places. 



The ore in the Hazel Green mines is usually found in sheets; this is its charac- 

 teristic mode of occurrence. The ranges are approximately east and west, or north 

 and south, the former being the most productive. Ore is also sometimes found in large 

 bunches or pockets, containing sometimes several thousand pounds, and occasionally in 

 openings. The pockets are often Lined with large and very regular cubes, affording 

 handsome cabinet specimens. The total production since the discovery of these mines 

 has been carefully computed from the smelter's accounts at about 126,000,000 pounds. 

 Their present product is about 800,000 pounds per annum. 



Mining in this vicinity is confined to the upper half of the Galena limestone, which is 

 here present in its entire thickness, the clay of the lower beds of the Cincinnati group 

 being found near the village, on the road to Galena. A section of the strata from the 

 top of the ridge to the level would present approximately the following features: 



Soil and flints 15 feet. 



Galena limestone 90 " 



Shales or thin layers of limestone 10 " 



First clay opening 10 " 



Second clay opening 20 " 



Flint opening to floor of level 20 " 



Total thickness 165 " 



The following are the parties who are now engaged in mining on the company's land 

 or have been during the course of the present survey: 

 Wis. SUR. 45 



