188 
GEOLOGY OF NORTH CAROLINA. 
This would evidently prove a valuable addition to some of the lean 
soils of the region, which are deficient in alkaline matter. The upper in- 
durated strata contain more than 90 per cent, of carbonate of lime, and 
the lower about 60 ; and both require to be burned before they are avail- 
able for agricultural uses. Lime was made at this point during the war, 
and used for building purposes in Raleigh. And some 40 years ago, a 
few kilns were burned for the same purpose, at a point a few miles south- 
eastward. There is an outcrop of a very similar character at Mr. H. 
Witherspoon’s, 2 miles east of B. 
Greensand Mart . — This is the great fertilizer of New Jersey, which 
has renewed the face of nearly the whole state agriculturally, within a 
generation, and mostly within a decade or two. The discovery of a marl 
bed in that region is justly regarded as an event of more importance than 
that of a gold or copper mine. One of the chief occupations cf the rail- 
roads in that state is the transportation of this natural manure from its 
depositories to the farms of almost every county. Prof. Cook, the State 
Geologist, mentions the fact that the amount transported in 1867, was 
about one million tons, and the quantity is constantly increasing, with 
the discovery of new deposits, and the construction of every additional 
mile of railway, so- that the amount for 1869 was estimated at double the 
above. No one passing through the State in any direction can fail to 
notice the marl heaps that line the track at every turnout, and almost 
every farm in some sections. 
As to the benefits which that state has derived from the use of this 
fertilizer, the following remarks of Prof. Cook are sufficient : “ Thousands 
of acres of land which had been worn out and left in commons, are now, 
by the use of this fertilizer, yielding crops of the finest quality. What 
are supppsed to be pine barrens, by the use of marl are made into fruit- 
ful land. Bare sands, by the application of marl, are made to grow 
clover, and then crops of corn, potatoes and wheat.” 
The composition of this fertilizer will be understood from the follow- 
ing specimens of analysis from the 
“ Geology of New Jersey, 1868. 
1. 
2. 
3. 
4. 
5. 
Silica, 
.... 51.16 
73.10 
49.40 
36.03 
38.70 
Alumina, 
Oxide of Iron, 
6.10) 
. . 17.68 f 
12.60 
8.90 
18.66 
1 
30.67 
Lime, 
. . 3.48 
1.62 
2.52 
15.19 
7.79 
Magnesia, 
.... 2.04 
3.25 
1.21 
Potash, 
. . . 4.27 
6.31 
4.47 
Phosphoric Acid, 
. . . 4.54 
1.20 
2.69 
1.23 
1.41 
