The Indianapolis journal., 1884-08-07

gan, are colored lilac, and represent the twenty
counties of Indiana where the surface rocks are
lower silurian. Tho next great area of surface
rock is the devoniau, occupying the upper fourth
of the State and extending in a wide central
strip, including Logansport Indianapolis and
Columbus, to the falls of the Ohio where this
rock appears as the grandest paleozoic cora! reef
in the world, and which has enriched with its
ancient corals and crinoids the museums Of
every country where geology is fostered or
studied
The balance of the map, including about two
ffths of the State, and nearly all that portion Of
Indiana lying west of the Jeffersonville railroad.
and of straight line from indianapolis to Chi
cago, is in fve coors, each representing an
epoch of the great carboniferous age. A wide
band of yellow represents the knobstone rocks
laid down in an age of quiet seas with sandy
margins affording the sandstone of Marion.
Brown and Floyd counties; to the west repre-
sented in green is the belt Of mountain lime
stone of the English geologists, centrally ira
versed throughout its hundred miles OF
length by the New Albany & Chicago railway.
and known by such thrifty centers and col
lege seats as Charlottesville, Greeneastle,
Bloomington Bedford and New Albany. In
this belt occurs the vast wealth of oolitic lime
stone, ''the best in the world, which has
served in the construction of most Of the public
buildings of the State, and has. also, been
chosen as the ornamental stone for adorning
sculpture and holdings in the most costly
public and private edifces of Chicago Spring
field, St. Louis, Louisville, Philadelphia and
New York, including the Vanderbilt palace
This stone includes beds of quaint and curious
fossils of the radiate group, so exquisitely fash
Toned and so rarely found elsewhere, that q
small. collection of them, such, for example. as
may be found at the ,Crawfords7
vile pocket, would serve one as
Introduction to the first museums of Europe.
These two groups--the knobstone and the mount
some of which have over fifty miles of explored
passages complete the lower carboniferous Pc
Rod The remainder of the map represents the
true coal measures. Indiana's liberal portion of
the carbouiferous wealth of the Mississippi Val
ley. about 7, 900 square miles of workable bitu7
minous coal, block. camel and coking, Here
are nearly thousand square miles Of the fa-
nous Indiana block coal, which is not only adj
mirably adapted to the manufacture of Bes-
semer Steel but also for rolling mill
household and locomotive use. This area of
coal alone has directed the construction Of over
a hundred miles of railroad for its development
and has added over fifty millions of dollars to the
wealth of the State.
Vertical sections appended to the map land
printed in identifying colors) show the relative
thickness of the various strata as they have been
measured in we'll bores and eroded outcrops
Another section shows the surface rocks and
relative elevations along the Ohio & Mississippi
railway from Lawrenceburg to Yineennes.
aa The State of Indiana is to be congratulated
that even at this late day graphic representa-
ton Of the geological features of its area-so
closely identified with its commercial and
economic welfare as they are--is now available
for the knowledge and instruction of its people
The map as whole, is Indicative of deter
mination on the part of the State Geologist to
give the people some adequate conception Of the
results Of the play and action of natures forces
in those long ages of the past when the earth
was preparing for man his home and dwelling
place.