Fossil Vegetables. 113 
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. 
Ihave 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 —- 
substance. 
I am led to believe, that fididepeiiaitly 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 shall become well acquainted with the botanical character of the 
plants of the primeval world. 
I shall be happy to receive any additional notices with which you 
may favor me, and I will, in turn, do any thing in my power to pro- 
mote this interesting research, on this side of the Atlantic. 
I remain, sir, very respectfully, 
our most obliged and 
very obedient servant, 
H. Wirnam, Esq. B. Smuumay- 
Vou. XXV.—No. 1. 15 
