ECONOMICAL GEOLOGY. 
205 
the depth of 5 feet beneath the soil ; is ash-colored, fine-sandy, with small 
shells little decayed. The same description of marl is found on the north 
side of Jackson Swamp, (at II. F. Harris’s,) just below Bath, but appa- 
rently more calcareous, and of better quality. On the shores of Pungo 
River, the banks of oyster shells, accumulated by the Indians, are used 
instead of marl. No. 56 is from M. J. Grist’s, near Washington ; it is 
exposed in the farm ditches. No. 57 is from Maj. Blount’s farm on the 
south side of the river, on Chockowinity Creek. This is a red marl, 
composed almost entirely of decomposed oyster shells. It is very abund- 
ant and within a few feet of the surface. At Durham’s Creek also marl 
occurs on Mr. C. Bonner’s farm. It is represented by No. 60; is quite 
sandy, and the shells small and not much decayed. The same descrip- 
tion of marl occurs on South Creek also, a few miles below Aurora, at 
Swindell’s and Reeves, 5 represented by 511. In the Bay River region it 
is also abundant, occurring at and around Jackson in the wells and farm 
■ditches; and also some 8 miles lower down on Bear Creek. The marls 
on both sides of Pamplieo River are of the same appearance and charac- 
ter. They are mostly composed of small shells, and are quite sandy, 
having therefore a smaller proportion of lime than is common. They 
are represented by No. 58 ; the sample was obtained from a tract on 
Bear Creek, opened by Dr. Abbott and others. The same sort of deposits 
is found on Smith’s Creek and Beard’s Creek; so that the whole penin- 
sula seems to be underlaid by it. 
Blue Marls of Roanoke River . 
It is reported that there is shell marl about Hill’s Ferry and in various 
parts of Martin county and in Washington near Plymouth, but I have 
not seen samples from any of these localities. 
Bine Marls of the Meherrin River . 
61 
62 
63 
64 
65 
66 
Silica, Insol. . . .. ... 
58.83 
56.31 
58.58 
63.00 
13.43 
43.69 
Silica, Soluble, 
1.26 
1.68 
1.08 
0.69 
Ox. of Iron and Alum , 
3.62 
6.88 
7.23 
4.65 
1.73 
7.60 
Lime, 
14.60 
17.51 
15.63 
15.96 
43.04 
24.04 
Magnesia, 
0.41 
0.79 
0.26 
0.50 
0.40 
0.93 
Potash, 
0.93 
0.73 
0.47 
0.25 
0.86 
0.85 
Soda, 
0.70 
0.15 
0.30 
0.12 
0.62 
Phosphoric Acid, 
0.18 
0.08 
0.21 
0.25 
0.54 
0.09 
28 
