were afterwards filled with crystalline matter; as, calcite, 
sulphate of strontian, etc. Sometimes these septaria seem 
to have aggregated around a nodule of iron pyrites, a 
shell, or some other particle of matter, for on being 
broken open such bodies are found within. Occasionally 
they contain cavities lined with crystals. 
Since we often find particles of coal, and a small per- 
centage of combustible material, distributed throughout 
the mass of this shale, numerous excavations have been 
made in it with the hope of finding sufficient quantities 
of these materials to make mining profitable. We occa- 
sionally hear of fortune seekers who are wasting their time 
and money in the vain hope of finding coal in this shale. 
In vain, because the limited amount of vegetation at this 
time clearly indicates that all such expenditures are in 
vain, and that the search for coal must necessarily be 
fruitless. 
It has, however, an indirect economic value, for by its 
disintegration our county receives a valuable addition to 
its soil. This is all the more valuable, because the soil as 
fast as it is formed on the sides and summits of our south- 
ern hills, is transported by the action of our streams to the 
valleys and levels beneath, and thus serves for our com- 
mon benefit. 
FOSSILS. 
Should we say that the Marcellus Shale is almost desti- 
tute of fossils, it is not at all likely that we would be con- 
tradicted by anyone who has hunted for specimens in the 
black shales which compose the greater part of this group. 
Indeed, this part of the group is almost non-fossiliferous, 
for it is only after the shales have begun to change to the 
thicker and harder layers of the Hamilton Beds that fos- 
sils appear. But, to the geologist, there is a part of the 
group vastly more interesting and important than the 
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