ORGANIC REMAINS AT PHILADELPHIA. 393 



appear to have been left there by the retiring waters. 

 Hickory-nuts were found a few years since, in digging a 

 well upwards of thirty feet below the surface ; and the 

 trunk of a sycamore (button-wood or platanus) was dis- 

 covered in Seventh-street, near Mulberry-street, about 

 forty feet below, imbedded in black mud, abounding 

 with leaves and acorns ; about sixty feet distant from that 

 place, a bone was found ; the stratum above was a tough 

 potter's clay. In various other parts of the city, and 

 even at the distance of several miles in the country, si- 

 milar discoveries have been made. Shark's teeth are 

 occasionally dug up many feet below the surface near 

 Mount Holly." 



The following fact is told of a fossil found in Mary- 

 land. Some men in working an iron-mine, at Bush-creek, 

 near the head of Chesapeake Bay, found the trunk of an 

 oak tree, thirty feet underground, fixed by its roots in 

 its natural erect position. The wood was penetrated by 

 the ore. The specimen of this curious transformation 

 was exhibited in Philadelphia. (Col. Mag. v. 1. p. 268). 



Alluvion of the Susquehannah. 



I cannot suppress the persuasion that great deposites 

 have been made by the impetuous stream of the Susque- 

 hannah. Spesutia island, Poole's island, and the adjacent 

 shores, bear witness of these circumstances. 



Near the end of October, 18 IT, charcoal and ashes 

 were found, fifty feet below the surface, near Elkton, at 

 the head of Chesapeake bay. The proprietor, Mr. Thomas 

 Moore, an inhabitant of Elktow-neck, and residing 

 four miles from the shore, was digging a well when he 

 discovered these articles. The quantity of charred coal 



50 



