612 THE GEOLOGY OF MINNESOTA. 



[Lime. Bricks. Mounds, 



f ectecl. For fifteen or twenty rods thence to the south, at a hight of 10 to 20 feet above the creek, 

 masses of calcareous tufa, free from gravel, but holding impressions of sticks and moss, are found 

 and have been burned by Mr. Trana, yielding a dark lime. 



At Island Lake post-office, also in western Lyou county, J. R. King has burned lime from 

 boulders eight years, averaging 200 barrels yearly, selling it at $1.25 to $2 per barrel. The greater 

 part of this is white lime, but about one piece in twenty is yellowish. The largest slab of lime- 

 stone found by Mr. King was about ten feet square and four feet thick. In the south edge of 

 this county, A. W. Bean burns lime from boulders in the southeast part of Kock Lake township. 



In Lake Benton; Lincoln county, Ira Scott and John Snyder burn lime from boulders, 

 white and of excellent quality, selling at $1.50 per ban-el. A few others burn lime in small 

 amount elsewhere in this county. 



Bricks. Before the Indian outbreak in 1862, but not since that time, bricks were made at 

 the old town of Yellow Medicine, on the bottomland of the Yellow Medicine river, in the south- 

 west corner of section 29, Sioux Agency. 



At Minnesota Falls two small kilns of bricks, amounting to about 100,000, were made in 



1879 by Simon Christianson, about twenty-five rods south from the mill, partially failing because 

 of small limy concretions in the clay and limestone particles in the sand used for tempering, 

 which cause the bricks to crack after burning. He intended to continue this business, expecting, 

 after these experiments, to produce bricks of good quality. The bricks are cream-colored or 

 light reddish, sold for $8 per thousand. They are made of recent alluvium, some 20 feet above 

 the river. About a foot at the surface is removed; then the next four to six feet of dark alluvial 

 clayey silt is used for this brick-making, mixed with considerable sand. 



Brick-making was undertaken at Granite Falls in 1876 and 1878, first a half mile southwest 

 from the bridge, and later near Stoddard & Libbey's mill, failing as at Minnesota Falls because 

 of the presence of limy concretions. 



Two miles northeast from Canby, a small kiln of bricks, containing about 10,000, of fail- 

 quality, dull gray in color, were made in 1878, beside Canby creek, from clay that is free of gravel, 

 tempered by a considerable intermixture of sand. 



In section 28, of Eidsvold, the most northwestern township of Lyon county, Anon Olson in 



1880 began brick-making, using clay and sand in the proportions of three and one. These are 

 red bricks, sold in Minneota, three miles distant, at $10 per thousand. 



At Marshall the business is carried on by W. A. Crocker, in the northeast edge of the town, 

 and by James M. Lockey, in its southwest edge, on the road to Lynd, both having begun in 1878. 

 Mr. Crooker made 500,000 bricks in 1880. They are cream-colored, but vary to pinkish, are of 

 good and durable quality, and command $7 to $8 per thousand. The material used is the allu- 

 vium of the Redwood river, lying about ten feet above this stream, but not overflowed at its 

 ordinary high water. It contains no gravel nor limy concretions, and no sand is mixed with it. 

 Mr. Lockey makes about 300,000 yearly, of similar color and quality, using the alluvium of an old 

 lake-bottom, which was covered by water in 1875. He mixes sand with it in the proportion of 

 one to three. 



In section 22, Verdi, the most southwest township of Lincoln county, John Enke began 

 brick-making in 1880. This is about five miles southwest from Lake Benton. 



ABORIGINAL EARTHWORKS. 



The only artificial mounds observed during the examination of these counties are near Lake 

 Benton station. About three-quarters of a mile northwest from this town, and within sight from 

 it, upon the top of the bluff 175 feet in hight, which forms the northwestern side of the "Hole in 

 the Mountain," are three mounds near together, of the usual circular form and about five feet 

 high. They are in the S. W. J of section 5, Lake Benton, on the crest of the Coteau des Prairies, 

 and are visible from the lower land on the northeast at a distance of many miles. One of these 

 mounds, excavated by Mr. C. M. Morse, contained several skeletons of men whose stature was 

 fully six feet. Another mound, also about five feet high, is situated on a high swell a half mile 

 east of Lake Benton station, in the center of the cemetery. 



