Lewis.] llZ [Dec. 2, 



On a New Substance resembling Dopplerite from a Peat Bog at Scranton. 

 By Ilenrij Carvill Leiois, Professor of Mineralogy in the Academy of Nat- 

 ural Sciences of Philadelphia. 



{Read before the American Philosophical Society, December 2, 1881.) 



In the course of an excavation for a new court-house at Scranton, Pa., 

 made last July, a very interesting substance was discovered, specimens of 

 which were sent to the writer at that time for investigation. The excava- 

 tion cut through a peat bog, and it was at the bottom of this bog, some 25 

 feet from the surface of the ground, that the substance here referred to 

 was found. 



It appears that formerly there had been a lake or swamp at this place, 

 which with the extension of the town had been filled up. Below eight 

 feet of cinder and other rubbish there is a bed of peat 10-12 feet in 

 thickness. The peat is said to be a good fuel after drying. Beneath the 

 peat is a deposit of "swamp muck" or carbonaceous mud, which dries to 

 a hard compact gray mass, burning with difficulty. In this "muck" 

 are numerous plant remains and occasional seeds. 



The whole deposit rests upon glacial till or "hardpan," and is therefore 

 of post-glacial origin. 



Scranton is in the glaciated portion of the State, and the peat bog found 

 here is one of the many which owe their origin to glacial causes. These 

 peat bogs have been formed, for the most part, in former swamps or lakes 

 caused by the damming up of sti'eams by ridges of drift deposited at the 

 time of the melting of the glacier. 



Near the bottom of the Scranton peat bog are irregular veins filled with 

 a black jelly-like substance, elastic to the touch. The veins of this sub- 

 stance, which are confined to the muck above described, vary in width 

 from a mere stain to between two and three inches, and make all angles 

 with the horizon, being frequently nearly perpendicular. 



The substance, as thus found, has the following properties : When first 

 taken from the ground it is jelly-like in consistency, breaking with a con- 

 choidal fracture, and having a hardness of less than 1. Immediately on 

 exposure to the air it becomes tougher and more elastic, resembling India 

 rubber. It may be preserved in this condition if kept in alcohol. The 

 substance is black by reflected light. When a thin slice cut by a knife is 

 examined under the mici'oscope it appears brownish-red by transmitted 

 light, and is nearly homogeneous in character. 



Occasional seeds occur in this substance as well as in the surrounding 

 peaty matter. In general appearance they resemble the seeds of certain 

 Cypcraceiie. Under the microscope their surface is seen to be curiously 

 marked with irregular wavy outlines. Professor J. T. Rothrock has been 

 kind enougli to make some sections of these seeds and reports concerning 

 them that they have the characters of spores of one of the higher crypto- 

 gams, probably Marsilia. He states that Marsilia is a bog plant which is 

 found during later geological time, and that the general shape and size of 



