996 Some observations in Holland, 
Arr. III.— Some observations in Holland, connected with our 
Prairie region. 
Dry Prairies. 
Ridgely, (near Portsmouth,) Va., Sept. 28, 1837. 
TO THE EDITOR. 
Dear Sir—In some early numbers of the Journal of Science there 
is I observe, a discussion respecting the origin of our western prairies, 
some of the writers attributing it to water, others to fire. My object 
in writing to you is not to meddle with the theory either of these 
Neptunians or Plutonians, but to state a circumstance which I ob- 
served a few years since in Holland and which may be useful to 
others in forming theories. 
I spent the winter of 1831-2 in Indiana, and had then an oppor- 
tunity of seeing some of our smaller prairies. My residence was on 
the border of what are there called ‘the barrens,” a district suffi- 
ciently fertile, but so called from its being less productive than the 
rich open prairie country adjoining. As far as I could learn, the 
prairies are arranged in the following manner. 
There commences near the southern termination of Lake Michi- 
gan, one of prodigious dimensions, being in many places one hundred 
and fifty miles in width. It extends transversely across the state of 
Illinois and passes down through Arkansas and Texas probably to 
the gulf of Mexico. It has numerous islands of trees scattered over 
it, and large promontories running out from its sides, but goes off in 
an unbroken stretch far to the south. 
This great prairie is bordered on the eastern side by a district 
about fifty miles in width which is occupied by smaller prairies, de- 
tached from each other by wood land, and of various dimensions. 
They are often as much as sixty miles in length and twenty or 
twenty five in breadth: but generally they are smaller, the average 
being about one third of those dimensions. ‘The soil and natural 
products in these do not differ from those of the large prairie just 
noticed. In my rides over them I sometimes carried an auger with 
me, and on boring, found the surface to the depth of about eight 
inches to consist of a black loam exceedingly rich: beyond this 
depth it began to change toa yellow color, and at twelve inches 
from the surface I came toa yellow clay. Below this they come 
in digging wells to rolled pebbles ; the thickness of this stratum I am 
