160 
[Assembly 
Notwithstanding this heavy tax upon our farmers for the importation 
of a mineral manure, they cheerfully pay it, because they are amply re- 
munerated by the increased productiveness' of their farms. The use of 
marl may prevent a large portion of this outlay, and it is sincerely hoped 
that our intelligent farmers will make the experiment of the marl, which 
is so abundant, and which has been accumulating during successive ages 
of time, by the growth and decay of myriads of animated beings, w^ith 
a view to the final benefit of man. 
The term marl, in its strict mineralogical sense, means an argillaceous 
carbonate of lime, but by general usage, marl is an earthy mineral sub- 
stance, which by being spread upon the soil, renders it more fertile. 
The marl which we have been describing, is a fresh water shell marl. 
The marls of New-Jersey, and the States south of it, are various in 
composition. Some are calcareous, and others are composed of green 
sandy grains, whose chemical composition is a potash silicate of iron. 
The marls of these States are marine depositions, and contain an abun- 
dance of the remains of marine animals. The fresh water shell-marl of 
New-York will not yield to any other in its fertilizing effects, unless to 
the green marls of New- Jersey and Maryland. If it be judiciously em- 
ployed, it will return millions to the pockets of our farmers. The ar- 
gillaceous marls will be discussed in another place. 
At most of the localities above mentioned, estimates have been made 
of the number of cart loads, allowing one-third of a cord in bulk to 
make a load. The aggregate of the estimates is 2,725,000 loads of 
marl, which ought, and will doubtless, be worth $1 per load to the 
owners, and it is presumed that not more than one-half the locali- 
ties of this useful and valuable fertilizer were observed. 
Peat. 
The characters, mode of formation, and the uses of this lacustrine and 
marsh alluvion, have been already discussed in the second section of this 
report. It now remains to mention the most important localities, ob- 
served in Columbia and Dutchess counties. 
Local Details. 
A large portion of what was once a part of Peat Marl pond, four 
miles north of Kinderhook, is filled with peat, and has become a marsh 
Other parts of this pond are filling with the same combustible, and with 
shell marl. It is estimated that 60 or 70 acres of this pond and marsh 
are filled with peat. It has probably a mean depth of at least six feet, 
