164 
GEOLOGY OF THE FIRST DISTRICT. 
however, that the banks of rounded masses of rock, pebbles and gravel, indicate the action 
and transporting power of water. An examination of the manner in which pebbles are formed 
in a rapid stream, or on a shingle beach ; the manner in which sand, gravel and pebbles, are 
deposited where washed along by water, till they find a resting place, and then compci,ring 
the appearances with those of the beds alluded to, will convince the most skeptical. 
The terms boulders and erratic blocks, also imply that these masses of rock are more or 
less removed from the place where they were formed. They are. loose masses, spread over 
or imbedded in the soil, and frequently they are different from the rocks in place in the vici¬ 
nity ; but it is observed as a general rule, that the larger masses and blocks are nearer their 
parent sources, while they diminish in size as they are more remote from them. These 
boulders and blocks are scattered not only over the valleys, plains and hills of moderate ele¬ 
vation, but they are found on the peaks of high mountains. The boulders, blocks, pebbles, 
gravel, etc. of the drift, embrace specimens of all the various rocks in the district where they 
are found, that are able to withstand the rough usage to which they seem to have been sub¬ 
jected. 
The materials of the drift deposits, from the gravel, to blocks and boulders weighing hun¬ 
dreds of tons, are often far distant, not only from hills and mountains, and from every known 
locality from which they may have been derived, but are separated from their parent sources 
by immense plains, broad and deep valleys, or by broad and deep lakes and arms of the sea. 
Notwithstanding all the study and investigation that have been bestowed upon the subject 
of the drift deposits, or diluvion, no one solution will account for all the phenomena of this 
interesting geological problem. 
It has been stated in my annual Reports on the New-York Geological Survey, that the 
sources of the boulders and drift of Long island and the Hudson valley, were in a northward¬ 
ly direction from the locations where they are now found. The facts will now be stated in 
regard to the boulders and drift, and for the upper drift as well as the lower, since the materials 
of both are the same, and in many localities on Long island they cannot be distinguished. 
These facts are the basis from which conclusions were drawn in regard to the direction of 
transportation in the First Geological District. The reader can examine them, and judge if 
the conclusions are well founded. 
The observations on boulders and drift on Long island will be first stated; then those of 
other islands, as Staten, New-York, Fisher’s, dec.; then those of the counties up the Hud¬ 
son and Champlain valley ; and then those of the Delaware and Susquehannah, of the coun¬ 
try around the Great lakes, of New-England, and of the Middle and Southern States. 
The facts stated are mostly the results of observations on the geological survey of New- 
p. 24.) Also in a range of gneiss that rapidly disintegrates, extending from Stonington through Voluntown in Connecticut, and Co¬ 
ventry and Foster in Rhode-Island. (Vide Mather’s Geol. Survey of New-London and Windham counties in Connecticut, 1834, 
p. 8.) This character may also be seen well illustrated in North Carolina, and in many parts of the gold region of the Southern 
States, where the less easily crumbling masses of granite and gneiss lie upon the surface of the earth or of the rock, and have 
been mistaken for boulders. 
