PORTAGE GROUP. 
225 
This group rises sometimes in a gentle slope, and at other times abruptly from the softer 
shales below. The enduring sandstones of the upper part have enabled it to withstand de¬ 
nuding action to a considerable degree, and these often extend far northward on the elevated 
grounds between the deep north and south valleys, presenting a gentle northern slope to the 
shales of the Hamilton group; while on the sides of the same hills the slope is abrupt, and 
the surface being but little covered with northern drift, the valleys are bounded on either side 
by steep hills. This character is well illustrated along the southern part of the Genesee valley 
towards Dansville, and in the valleys of Allen’s creek, the Tonawanda, and the different 
branches of the Seneca and Cayuga creeks. The same is also seen in the valleys of Mud 
creek, Flint creek, Canandaigua lake, and to a greater or less degree along all the valleys and 
streams which extend into this group. 
The change in the external appearance of the country indicates the commencement of these 
rocks, although they are not seen. The valleys just spoken of, in their course through the 
shales of the Hamilton group, present gently sloping sides, and the country rarely rises far 
above the level of the valley bottom or bed of the stream. On approaching the northern margin 
of the Portage group, the observer finds a gradually increasing elevation of the hills on either 
side, and an abruptness in their slope ; and in a short time he finds himself in a deep valley, 
bounded on either side by hills rising four or five hundred feet, and in some instances even 
eight hundred feet above the bed of the stream. These elevations often extend several miles 
unbroken, except partially by the deep ravines which indent their sides, and which have ori¬ 
ginated in recent or ancient water courses which took their rise upon the summits of these hills. 
The higher sandstones of the group, and in many instances some of the intermediate ones, 
produce falls in the streams which pass over them, and some of the most beautiful cascades 
in the State are found among the rocks of this group. The highest perpendicular fall of water 
in the State is produced by the rocks of this group, and in none others do we meet with more 
grand and striking scenery. The pedestrian often finds his course impeded by a gorge of 
several hundred feet in depth; and in the very bottom of this, and scarcely perceptible, is the 
winding stream, the only representative of the once powerful torrent that has excavated the 
deep channel. Farther on, above or below, he may see the little stream dashed over a pre¬ 
cipice, and almost disappearing in spray before it reaches the bottom ; here, however, it gathers 
itself in a deep pool, from which it flows on quietly as before, or gurgling and dashing through 
the fragments of the fallen cliffs, it finds its way into the gently sloping valley of the softer shales. 
So numerous are these falls in the district, that to present even an enumeration of them 
would fill a page. Among these have been selected for illustrations, either from their beauty 
and interest, or from being accessible places, the following : Portage Middle and Upper Falls, 
Portage Lower Falls, Taghannuck Falls,* Hector Falls, and Lodi Falls. The first of these, the 
illustration at the head of the preceding page, is the locality giving name to the group. The 
river in view is precipitated over two falls of 66 and 110 feet respectively; and below the last, 
the rocks rise in perpendicular cliff's of 350 feet in height. 
* This is the aboriginal name ; the place is usually known as Goodwin Falls. 
[Geol. 4th Dist.] 29 
