488 WISCONSIN STATE AGRICULTURAL SOCIETY . 
careful judgment of the matter, a judgment formed from a recollection of 
similar ore in other parts of the world, I would say, that the yield will prob¬ 
ably be from 45 to 55 per cent, of iron. 
This bog iron ore, although its mode of occurrence may be different, and 
differ slightly, perhaps, in its physical characters, is no doubt in its chemical 
composition the same as the brown hematite found in Sauk and Richland 
counties, and principally represented atlronton; and lean see no reason 
why this bog ore here, may not be as valuable for all practical purposes as the 
hematite there, unless it should contain more phosphorus among its impuri' 
ties as bog ore in some places is apt to do. This, however, can be deter¬ 
mined only by analysis, or actual w r ork in the furnace. These ores, both the 
hematite and bog, are among the important ores of iron, and deposits of any 
considerable extent will remain but a short time undeveloped, after proper 
notice of their existence has been given. 
Bog iron ore is supposed to be formed by deposits from water, the water 
obtaining the material, either from disintegrated deposits of iron ore on the 
surface, or from iron contained in the strata through which it flows in the 
form of springs. This water, with the iron dissolved in it, finding its way 
into depressions on the surface, and coming in contact with decomposing or¬ 
ganic bodies, is deprived of its iron by chemical re-action, produced wholly, 
or in part, by this decomposing organic vegetable matter. To form 
such deposits, it is not necessary that the water should be saturated with iron; 
small quantities dissolved in it are sufficient, in a long continuation of the 
process, to build up vast beds of ore in this way. This is one of the beauti¬ 
ful processes of nature, set in operation on the surface before our eyes, and is 
not altogether a process of the past, but is even now, in many places, in ac¬ 
tive operation. 
The first intimation of bog iron ore in this region, I obtained in the follow¬ 
ing manner: I was exploring on the east side of the Wisconsin river for the 
purpose of satisfying myself that the azoic rocks there, pitched beneath the 
sandstone. In my wanderings, I came to a small stream running into what is 
called Five Mile creek. 
It had rained heavily the day before, and the little stream had overflowed 
its banks, leaving vegetation.all stained with iron. The little stream itself 
looked more like water pumped out of an old mine, than water flowing from 
springs. After securing my horse, I made my way up this little stream to its 
source, which I found to be in a marsh at no great distance. On the borders 
of the marsh, the water had cut a deep furrow, or rut, into a very brown, 
irony soil, very deep, and containing a large amount of decomposed vegetable 
matter. Here for the first time in Wisconsin, I found good specimens of bog 
iron ore. The soil here on the borders of the marsh contains a large amount 
of iron in an earthy, ochreous condition, which is readily taken up and re¬ 
moved by the water, leaving the purer ores exposed. Mr. Aber, a son of the 
gentleman on whose land the ore is found, told me that a little farther up in 
the marsh, there is an extensive bed of some kind of ore. It was at that time 
