21st.] For three or four nights past, we experienced frost sufficient to destroy most of the early grape, plum, popaw, and red-bud bloom. At 6 o'clock this morning, the thermometer was down to 22°. In the distance of two miles we arrived at the younger Mr. Curran's, nearly opposite to whose house appeared gentle hills, presenting along the bank of the river beds of slate dipping about 45° to the north-west. About two miles above, commence on the right bank of the river, the first hills, or rather mountains, {106} being not less than 4 or 500 feet high, and possessing a dip too considerable to be classed with the secondary formation. Their character and composition refer them to the transition rocks, and, as far as I have had opportunity to examine, they appear, at all events, generally destitute of organic reliquiæ. Similar to what we had already examined, they are a stratum of slate made up of the detritus of more ancient rocks, and frequently traversed with crystalline quartzy veins. I cannot, in fact, perceive any difference betwixt this rock and that of the greater part of the Alleghany mountains in Pennsylvania and Virginia, and particularly those which are of like inconsiderable elevation. About eight miles from Mr. Curran's, appeared again, on the left, very considerable round-top hills, one of them, called the Mamelle,[127] in the distance, where first visible, appeared insulated and conic like a volcano. The cliffs bordering the river, broken into shelvings, were decorated with the red cedar (Juniperus virginiana), and clusters of ferns.
After emerging as it were from so vast a tract of alluvial
