858 PAPERS RELATING TO ANTHROPOLOGY. 



stone, which is not solid, as in some other places, but is in thin layers, 

 between which a thin parting of clay is occasionally found. 



The total thickness of the flint here was 29 inches. IS'ext is a layer 

 of bluish clay ; on the top of this the sulphur set free by the decompo- 

 sition of the sulphide had collected in a thin veneer. 



The clay continues pure only for 2 or 3 inches ; then sand appears mixed 

 in with it ; a little lower some lime also enters ; next it is in thin plates ; 

 and finally, at 16 inches, it runs into the solid limestone. The clay is 

 quite soft, but as the sand and lime become mixed with it the whole 

 grows harder and more compact. 



This same blaek flint is found east of here, beginning near the next 

 section line and extending eastward for half a mile, and also at the ex- 

 treme southeastern spur of the ridge. 



A grayish, banded flint, presenting very narrow stripes of white or 

 light gray, alternating with darlier shades of the same color, is found a 

 few hundred yards southeast of the cross-roads in rather limited quan- 

 tity. On the farm of Joseph Duncan the same flint occurs in great abun- 

 dance, the whole outcrop being of this nature on a i)oint north of his 

 house. 



At the eastern end, along the Muskingum line, the flint has much the 

 same appearance as at the western end — a buhr-stone that has been 

 quarried to a considerable extent by the whites for making mill-stones. 

 At the eastern termination of this stratum a white flint is found, having 

 occasionally places in which iron has given it a re'ddish tinge. 



It would seem, so far as can be judged from the limited opportunities 

 for examination, that at the edges of the deposit, on every side, it is more 

 in the nature of the buhr-stone, while through the central part, proba- 

 bly owing to clearer or less disturbed waters, the formation of a denser, 

 purer siliceous rock was possible. Scattered around the pits, to be 

 spoken of later, south of the blacksmith shop, at the cross-roads, near 

 where the "shaft" mentioned above was sunk, can be found all the colors 

 and shades mentioned, while farther away, in all directions, it seems to 

 be of one general character. JNiuch of it answers to the description of 

 chalcedony, nearly all at the central points being translucent or even 

 transparent. The so-called " black flint" is not the opaque variety, basa- 

 nite, found in other parts of the Coal measures, but a clear, vitreous kind, 

 containing a large amount of iron and carbonaceous matter, to which its 

 color is due. This is proven by finding pieces almost perfectly transpar- 

 ent from the absence of impurities, and ranging from that to a deep 

 black that is translucent only in the thinnest flakes. Some of it has the 

 coloring matter so distributed as to resemble moss agate very closely; 

 a variety occurs which has a beautifully mottled or clouded appearance, 

 due ])robably to the entanglement of some gas in the silica at the time 

 it was deposited, the cloudy part being sometimes in spots, again in 

 narrow stripes, and occasionally in bands, which make it resemble small 



