OF DODGE COUNTY, WISCONSIN. 451 
peroxide and carbonate of iron, with 15 per cent. of siliceous and argillaceous 
matter. 
The analysis* of the Sterling ore, as given by Professor J. L. Cassels, of the 
Medical College at Cleveland, Ohio, indicates over 53 per cent. of iron. 
Of the extent of this deposit, with so little excavation, and but a hasty examina- 
tion of the region, in unfavourable weather, I can say little. It is already exposed 
in sufficient quantities to make it a certain supply for a long time ; and theoretically 
it should occupy extensive tracts, where it is not visible, to the south and east. It 
probably exists in a wedge-shaped mass, between the rocks with irregular faces, 
giving it somewhat the character of nests, connected by thinner portions of the ore, 
the whole tapering towards an edge as it enters the hill. I find no examples of an 
ore having this internal structure, unless some of the ores described as oolitic, are 
intended to include other than rounded grains. Professor Cassels has seen iron ore 
in Scotland, having the same structure as Dodge County ore, and the same greasy, 
adhesive touch. 
The Wisconsin Iron Company, under the management of John Niles, Esq., use 
the ore without burning, and find it to melt very easy without flux; in fact, it 
has been found necessary to introduce silex, in the shape of water-washed sand, to 
retard the process of melting, and thus improve the quality of the metal. In 
November, 1849, their charge consisted of fifty-five pounds of bog ore, sixty-six 
pounds of sand, thirty-five pounds of limestone, and six hundred and sixty pounds 
of the ochery ore, unburnt. The yield, with a moderately hot blast, was 35 to 42 
per cent. of iron, the furnace running out three and a half to four tons of metal per 
day, of twenty-four hours, with a consumption of one hundred and forty-five to one 
hundred and fifty-five bushels of charcoal per ton. The castings were very smooth, 
and the sound and texture of the metal was good, but seemed to be less tough than 
other castings. The manager was about to try the effect of cold blast on the quality 
of the iron. I cannot learn that it has been wrought into bars. 
* Peroxide of iron, . ‘ : . ¢ 16-74 198 a eae 
Sesquioxide of manganese, . : : : 1-05 
Clay, ‘ j R ; : : 4-00 
Silex, ‘ : i ' , i 10-00 
Water, . : ‘ ‘ : ‘ 6-00 
Loss, : ; . ‘ ‘ ‘ 2.21 
