CRETACEOUS FORMATION. 85 



outcropping, but, as had been stated, 20 to 30 feet 

 below the surface of the uplands; the country being 

 but slightly undulating. At Dr. Clingscale's, Sec 

 tion 8, Township 5, Range 11 east, the clay stratum 

 was struck at the depth of about 30 feet beneath sand 

 and pebbles; it was dug into, without being passed 

 through,, for nearly 30 feet more, no water being 

 obtained from below, but dripping in above from the 

 base of the pervious strata. The whiteness and 

 plasticity of the material seems to increase with the 

 depth. The portion of what was dug out of 

 the well in question, had already been removed 

 at the time of my visit, having been used 

 for various economical purposes as, chalk, 

 whitewash, and "Lily White". The specimens 

 examined were, therefore, rather below the average 

 quality, and on long exposure to the air, their surface 

 shows some yellowish spots. I found nevertheless, 

 that in baking at a high heat they yielded a biscuit of 

 greater whiteness than their natural color when 

 fresh; and that fine splinters, exposed for ten minu- 

 tes to the highest heat of the mouth blowpipe, retain- 

 ed their shape perfectly while reduced to a semi-trans- 

 parent frit. A quantitative analysis of the clay from 

 Clingscale's well gave the following results: 



White Pipe Clay from Clingscale's. 



Insoluble matter 9n.f77 



I im« 0.140 



Magnesia trace 



Peroxide of Iron 0.126 



Alumina 2 214 



Water 6-930 



99.861 



This analysis (which was made solely for the pur- 

 pose of ascertaining the ingredients foreign to the 



