Observations on the Occurrence of Anthracite. — Gresleii. 7 
typical bituminous coal capped by fish beds* we almost 
possess just the conditions of deposition which Stevenson 
would apply to the anthracite region but scarcely look for in 
the non-anthracitic areas; so that, if the occurrence of fish 
beds is any index of delayed on-coming mud or sand deposits, 
then, on Stevenson's theory, the bituminous coal ought now 
to be anthracite and the now anthracite bituminous. 
7. Lamination or " grain " frequent in anthracite. Had 
the vegetable accumulations really been unusually long ex- 
posed to the coal-forming process prior to sealing over by 
sand etc., as per theory of Stevenson, it seems not unlikely 
that the process would have caused the entire obliteration 
or extinction of the " grain " or horizontal lamination of the 
coal, in a manner somewhat analogous to modern peat, which 
we know loses its fibrous or original plant structure the older 
and the deeper it gets in the bog. That this anthracite of 
Pennsylvania possesses its original lamination structure is 
perhaps not so widely known or admitted as it deserves to be. 
As a matter of fact there are very few layers indeed (or hand 
specimens for that matter) to be picked up anywhere which 
do not clearly reveal this lamination when looked for ; in fact 
much of it is as apparent and as sharply and as clearly pre- 
served as the lamination or characteristic grain of the typical 
bituminous coal of the western coal field. Excepting for dif- 
ferences in fracture and lustre it is often difficult to tell 
specimens of anthracite and soft coal apart. The peculiar 
shelly and rugged fracture of anthracite and the oblique 
cleavage planes by which it is so generally broken up, make 
the grain of this coal comparatively obscure. 
IV. Pennsylvania Anthracite had a Metamorphic Orkhn, 
BUT IS not a Product of Folding. 
It is perfectly clear, therefore, to my mind that whatever 
was the cause of the debituminization or anfhracitification of 
the coal of the thick seams as well as of that upon the fossil 
plant remains, and the local scattered insignificant i)Ockety 
patches or films and streaks of coal enclosed in the slates and 
sandstones, it was one and the same. And since the whole 
*Cf. Bull. U. S. Geol. Sur., No., G5, 1891. The author has discovered 
a fish horizon on top of the main bench of the "Pittsburg? coal." See 
Final Report Pa. Geol. Surv., vol. iii, part 2 — second footnote on 
page 2,452. 
