The Making of Pennsylvania. — Claypole. 231 
enormous quantities of sand and burying beneath it the veg- 
etable growth over thousands of square miles is difficult to 
imagine and the repetition of this over and over again to form 
the many beds thick and thin that compose the coal 
fields of Pennsylvania indicates an oscillation of level quite 
beyond the range of our experience. Yet at the time in ques- 
tion such seems to have been the condition of things over the 
whole state and even far beyond its limits. The massive 
anthracites of the East, the semi-bituminous coals of Bloss- 
burg and Broad Top and the soft but inexhaustible fuels of 
the West all agree to tell us the same story of the time of 
their deposition, when for thousands and tens of thousands of 
years the whole middle and western part of the state was one 
vast coal-growing swamp of varying rankness and luxuriance 
but each part contributing its share to the production of this 
staple of Pennsylvania. 
To one familiar with the state or even well acquainted wdth 
its map the above description of it during the Carboniferous 
era may sound extravagant. Knowing the small area to 
which the coal-fields are limited he may be surprised to hear 
of the prevalence of coal-making over so great a region. But 
probability leads us to the belief that these conditions pre- 
vailed wherever the later palaeozoic sea had spread within the 
state. The present isolated coal-fields of Pennsylvania were 
probably once connected and a vast series of coal-sw'amps 
existed from the most easterly point where coal is now found 
across the state to the west, forming a store of mineral fuel 
compared with which even her present liberal supply is insig- 
nificant. This point will be better appreciated when the 
process of rock-destruction has been considered. 
The end of the palaeozoic era was now approaching and 
geology to our eye reveals the state of Pennsylvania as one 
dismal, trackless, impenetrable maze of low lying land, of 
swamp and morass, of pool and lake, clad with an obsolete 
vegetation and tenanted by animals whose highest types con- 
sisted of a few reptiles and amphibians. No mountain or 
even hill broke the monotony of her western and central flats 
and if rivers drained them, as they probably did, they wound 
along slow and almost stagnant, in for the most part a south 
©r southwest direction. Subsequent changes have, however, 
so completely efiaced their channels that it is quite impossible 
