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mud by rain at Brooklyn in Long Island (New York). On the 
same mud were the foot-prints of fowls, some of which had been made 
before the rain and some after it. 
Mr. Lyell next visited the red and green shales of Cabotville, north 
of Springfield in Massachusetts, where some of the best Ornithich- 
nites have been procured, chiefly in the green shale. The dip of the 
beds is 20° to the east, a higher inclination, the author says, than 
could have belonged to a sea-beach. He observed in the same quar- 
ries ripple-marks as well as casts of cracks, and he was informed 
that the impressions of rain-drops have likewise been found. 
In company with Prof. Hitchcock, Mr. Lyell afterwards examined 
a natural section near Smith’s Ferry, on the right bank of the Con- 
necticut, about eleven miles north of Springfield. The rock con- 
sists of thin-bedded sandstone with red-coloured shale. Some of the 
flags are distinctly ripple-marked, and the dip of the layers on which 
the Ornithichnites are imprinted, in great abundance, varies from 
eleven to fifteen degrees. Many superimposed beds must have been 
successively trodden upon, as different sets of tracks are traced 
through a thickness of sandstone exceeding ten feet; and Prof. 
Hitchcock pointed out to the author that some of the beds exposed 
several yards farther down the river, and containing Ornithichnites, 
would, if prolonged, pass under those of the principal locality, and 
make the entire thickness throughout which the impressions prevail, 
at intervals, perhaps twenty or thirty feet. Mr. Lyell, therefore, con- 
ceives that a continued subsidence of the ground took place during 
the deposition of the layers on which the birds walked. 
It has been suggested, but the opinion has not been adopted by 
Prof. Hitchcock, that the eastward slope of the beds represents that 
of the original beach. With a view to this question, Mr. Lyell exa- 
mined the direction of the ripple-marks, and found that it agreed with 
the dip, or was at right angles to the supposed line of beach; but he 
adds, though this agreement presents a formidable objection to the 
suggestion above alluded to, if the ripples were preduced by waves, 
yet it does not disprove the opinion, as the ripples do not exceed in’ 
dimensions those which are produced by sand blown over a muddy 
beach, and often distributed at right angles to the coast-line. In- 
stances of this effect of the wind Mr. Lyell has remarked along the 
shores of Massachusetts. Nevertheless he is of opinion that the 
rippled layer of sandstone in question contains too much clay to have 
resulted from blown sand, and he is disposed to think that in most 
of these localities the strata have been tilted, instances of such dis- 
turbance having been pointed out to him by Prof. Hitchcock in the 
state of Massachusetts, and by Mr. Percival near Newhaven in Con- 
necticut. In reference to this subject, he says, that a few miles from 
Smith’s Ferry a conglomerate, several hundred feet thick, containing 
angular and rounded fragments of trap and red sandstone, the base 
being sometimes a vesicular trap and trap tuff, passes upwards into 
the very flags on which Ornithichnites occur; and from this he infers, 
that there were eruptions of trap, accompanied by upheaval and pare 
tial denudation, during the deposition of the red sandstone. 
