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when the immense surplus should be exhausted. It has produced all the 
advantages that its most sanguine friends could claim for it, in preventing 
in a large degree, ruinous depression and the sacrifice of flocks, and in paving 
the way for entire success in the future, which shall benefit every interest of 
agriculture and every brauch of industry. 
GREENSAND MARL AS A MANURE. 
To the farmers of eastern Maryland and northeastern Virginia a new means 
of enrichment of the soil has been added in the exploration and development of 
the marl beds of Prince George’s and neighboring counties of Maryland. 
Although these beds have been known to exist for many years, they have but 
recently received that attention which they merit. Very many openings, have 
been made along the eastern edge of the District of Columbia, from whence large 
and increasing quantities of marl are being drawn for the uses of the vicinity. 
While these beds are found in localities, as beds of sand and gravel, with shells, 
and are thus somewhat like alluvial sand and clay hills, they are of much older 
formation than the common surface soil or the marl pits which exist at the bottom 
of old lake beds and water-courses. Indeed they are of so respectable antiquity 
that at the period when these green marl beds were being deposited in shallow 
estuaries, there existed upon this continent no great number of avimals known 
as the mammalia. The predominance of the type of the life of the world at that 
period was reptilian, and while these marl beds were being formed here, under 
similar conditions in Europe the vast beds of chalk which line the southern coast 
of England and the channel shores of France were deposited. Hence these beds 
are everywhere classed as belonging to the cretaceous or chalk formation, consti- 
tuting a series of rocks and beds which have pretty uniform characters. Where 
these beds now exist marks the place at which courses of water ran earrying 
down large bodies of sand and gravel to be deposited in the ocean further down. 
In fact, where these beds now are was formerly the basin of a considerable 
estuary, in which tidal action was tolerably powerful. Along the eastern shore of 
the States there is no deposition of chalk, but in the region west of the Missis- 
sippi, where the same formation recurs the beds are better developed, more 
calcareous, and soliditied into rock strata. 
In New Jersey, Delaware and Maryland, they constitute alternate layers of 
sandy and micaceous clay, between which are intercalated beds of a greenish 
sand, the upper layers of which contain shell remains. 
The lower beds of the chalk formations in Europe have been called green- 
sand beds, on account of their color and texture. In this country the upper 
beds have the bluish green tint, and are found most abundantly in New Jersey, — 
where they are met with in Monmouth, Burlington, Gloucester, and other coun- 
ties. ‘The green color of the marl beds is due to the large amount of sand made 
up of fine blue grains, rounded and polished like the fine rolled sand of a river 
bottom. These grains mixed, with yellowish clay, or sand, give the greenish 
tint to these strata; they resemble gunpowder in size, and are softish, so that 
when crushed by the finger nail a green streak is left on paper. These beds in 
New Jersey have a slight slope dip towards the east or southeast, and are 
generally worked at water-level, or a very few feet above tide-water. The 
whole formation in New Jersey may be from 300 to 400 feet thick, and contain 
three workable beds of greensand marl, some of which are, in different counties, 
from 20 to 30 feet thick, and are great sources of wealth to the farmer  pro- 
prietors, and for some years past the Freehold and Jamesburg and Camden and 
Amboy railroads have carried immense quantities of it to various stations on 
