Fossil Ves^etables, 113 



<b 



just heard, that some huge stems have been recently discovered in 

 one of the anthracite mines of Pennsylvania, but, my information is 

 not precise, although, from the source, I believe it to be authentic. 



I have a mass of American anthracite, received not long since, 

 which contains a compressed vegetable branch as large as a human 

 arm ; it is distinctly fibrous, like charcoal, and forms a strong contrast 

 with the general lustre and conchoidal fracture of the surrounding 

 substance. 



I am led to believe, that (independently of the impressions which 

 are so common in the shales and other attendant rocks,) vegetable 

 structure may be developed in the very mass of coal itself, much 

 more extensively, than has been generally imagined. Our Pennsyl- 

 vania anthracite, (a stupendous formation,) affords vegetable fibres, 

 in many places, provided the fracture be made, in a particular di- 

 rection, between the layers of coal ; "if across, or aslant the layers, 

 no fibres appear, but only a lustrous, conchoidal, or sub-conchoidal 

 fracture. The same is the fact with an immense deposit of bitu- 

 minous coal upon the banks of the Ohio, between Pittsburgh and 

 Cincinnati. This coal appears to be one entire mass of plants, 

 whose structure is revealed, often with great distinctness, provided 

 the fracture be made, as above stated ; otherwise, it has only the usual 

 appearance of glance coal. The same vegetable tissue which is 

 perfectly apparent in one direction, is completely disguised, if the 

 fracture be made, obliquely or directly across the structure, and a 

 similar difference is observed, on fracturing in the same manner, a 

 piece of common charcoal. I shall take the liberty, with a view of 

 exciting attention to the subject in this country, to publish your let- 

 ter and this hasty reply. Your mode of developing the structure 

 of fossil plants is, I believe, entirely original, as it is certainly most 

 ingenious, and I hope it may be repeated in many countries, until 

 we shallbecome well acquainted with the botanical character of the 

 plants of the. primeval world. 



I shall be happy to receive any additidnal notices with which you 

 may favor me, and I will, in tiirn, do any thing in my power to pro- 

 mote this interesting research, on this side of the Atlantic. 

 I remain, sir, very respectfully, 



Your most obliged and 



very obedient servant, 



H. WlTHAM, Esq. B. SiLLIMAN, 



Vol. XXV.— No. 1. 15 



