KAOLIN" IN" WISCONSIISr. 



19 



The fluxing ingredients, iron oxide, lime, magnesia, potash, soda, 

 very small in the original clay, have thus heen removed largely 

 (five-sixths) by washing. The following are other determinations 

 made on samples from the same locality, all in the raAv state: 



IV. is the bright yellowish clay from near the surface; V. is some- 

 what less yellow but apparently more ferruginous. It is the most 

 abundant kind. VI. is white clay, still retaining, to a marked de- 

 gree, the lamination of the original roclc. It \yould appear, how- 

 ever, to be much more thoroughly decomposed than much of the 

 more homogeneous clay of the region. VII. is a highly micaceous 

 weathering granite from the river bank near by the kaolin pits. 



On the northwest quarter of the southwest quarter of section 4, 

 town 22, range 6 east, on the east side of the Wisconsin river, near 

 the centre of the section, kaolin occurs overlaid by ten feet of friable 

 sandstone. Most of it has lost the rock structure, though this ap- 

 pears very distinctly in places. This clay is one of the whitest 

 looking noticed. It has been used for making hearth at the Grand 

 Rapids foundry. The following are Mr. Sweet's analyses of sam- 

 ples from this place: 



VIII. is the raw clay; IX. the same washed. X. is raw clay taken 

 from the box at the foundry, and said to come from the same place; 

 XI is the fine portion of X. The removal of alkalies by washing 

 is here evident. 



