No. 200. 1 
147 
earthy matter, the ooze (or muckj as it is frequently called by our far- 
mers) will probably predominate. When the soils contain much lime, 
or if calcareous springs occur in the vicinity, fresh water molusca will 
probably exist in quantities and cause the deposition of shell marl; if 
neither of these causes should predominate, vegetable matter will accu- 
mulate so as as to form peat. 
The ooze, or muck, of our swamps and " pond-holes," is a black mud, 
composed of a mixture of earthy matter, with decayed remains of plants, 
of animals and their excretions. It is highly valuable as a manure, 
and is extensively used for this purpose, yet our farmers, as a body, 
do not seem to appreciate its value. 
Fresh water Shdl MarL 
Fresh water shell marl is very abundant in Columbia and Dutchess 
counties. It is formed by moluscous animals secreting lime from the 
waters of the lakes and ponds in which they live, to form their shells; 
and as generation succeeds generation,' the dead shells accumulate, and 
form thick and extensive beds of white shell marl. When the pond or 
lake has shoaled to within a few feet of the usual water level, plants 
grow and decay, and by accumulation form peat, which, in marshes that 
were once ponds, covers the marl. For a foot or two from the surface 
of the marl, the peat is filled with small fresh water shells, similar to 
those which have crumbled down to form the proper marl. The pure 
marl is^a white crumbly mass when dry, but unctuous and plastic when 
wet, and contains a few small, white, fresh water shells. If vinegar, or 
any acid, be poured on it, it effervesces, or boils up strongly. Shell 
marl was seen in process of formation in Peat Marl pond, about four 
miles north of Kinderhook, and a little east of the post road. Standing 
on the adjacent terrace which surrounds the lake, white shoals were 
seen, which, on examination, proved to be beds of white shell marl, and 
which had accumulated by the successive growth and decay of myriads 
of fresh water shells. The !ake is gradually shoaling, from this cause 
and the deposition of peat. This lake was once far more extensive than 
it is at present. These causes have continued to act, until the alluvi- 
ons have reached the surface, and formed a marsh. Large quantities of 
marl can be obtained here by draining the lake. This marl ought to be 
worth at least one dollar a load for use as a manure. The data for es- 
timating the quantity of this material are necessarily imperfect, but it is 
probable that there are at least 100,000 cart loads of marl in this lake. 
