GEOLOGY. 17 



to a pure white. Some of them are beautifully striped with 

 reddish and whitish streaks. 



l/lXRBhK, 



Resembling that found near New Haven, Connecticut, exists 

 on Monday creek in Hocking county, in amorphous masses. 

 The texture of this beautiful marble, is fine, but granular. Its 

 colors are grey, or blue, richly variegated with clouds of 

 white, black and green. Green pervades the whole mass, it 

 takes a fine polish and endures the action of heat very well. 

 It contains chromate of iron, magnetic oxide of iron, and ser- 

 pentine. It is a most beautiful marble, and will, one day, 

 become as celebrated as that of Milford hills, Connecticut, 

 which had been used one hundred years, at least, for common 

 stone fences, before its value was discovered and made known 

 by Professor Silliman, many years since. 



LIAS. 



There is a deposite of this rock near Kingston, in Ross 

 county, near the line, which separates the sandstone from the 

 limestone formation, and east of that line, it underlies the 

 surface of about fifty acres of land, belonging to a Mr. Richie. 

 On being exposed to the atmosphere, it shows reddish stripes. 

 When burned in a hot fire, until it assumes a whitish appear- 

 ance, and then the heat ought to be taken from it. Pound it 

 until it is as fine as common slacked lime, it soon afterwards 

 assumes a dark appearance, and becomes, finally, a deep brown. 

 By mixing it with common slacked lime, in the proportions of 

 twenty eight parts of lime, to one hundred parts of the lias, it 

 hardens in water, almost instantly, and continues to harden, 

 until it is as hard as any limestone in this region. In the 

 burnt and granulated state, as before mentioned, by mixing a 

 certain proportion of salt brine with it, it colors every object 

 with which it comes in contact, a deep brown. Hence it is 

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