5« 



Cincinnati Society of Natural History. 



elements, and too heavy for the ordinary rains to carry away, 

 has remained in the eroded areas and valleys, while the lighter 

 materials have been transported. 



Now, standing on one of the outliers and looking across or 

 up one of these eroded valleys, we see, in one direction, 

 scattered here and there, the broken fragments of this chalced- 

 onized wood glistening in the sunlight; in another direction, 

 clusters of the short sections of the trees, coated with dark 

 oxide of iron, that look like veritable logs, and in another 

 direction where the oxidized sections have rolled together 

 and are still more numerous, they look like the logs sometimes 

 seen on imperfectly cleared fields. The trees may have been 

 two, three, four or five feet in diameter, but it is very rare to 

 find an unbroken piece four feet in length. I saw one log in 

 place about one hundred and fifty feet in length, but it was so 

 shattered that a good section could not be found in it three 

 feet in length. Sections two feet or less in diameter are gen- 

 erally solid, while those three or four feet in diameter are 

 usually defective, indicating the presence of decayed places in 

 the tree, and some of the larger pieces seem even to represent 

 a hollow tree. Possibly the trees ma} 7 have been shaken and 

 injured, and so perfect has the petrification been that the 

 defects are preserved, as well as the internal structure of the 

 trees themselves. 



