350 
GEOLOGY OF THE FOURTH DISTRICT. 
passage ; others have been closed up during its deposition, and formed little ponds upon the 
inland side, which, subsequently becoming powerful, have burst through the barrier, and carried 
away large portions of it. The original elevation and extent of many of these ponds on the 
south side of the ridge is still distinctly marked, although there is now but an insignificant 
rivulet flowing in their channels. 
The most important interruption in its course is at the entrance of the Eighteen-mile creek, 
in Niagara county. In passing from the east, we find, before reaching the creek, that it bends 
around to the south, showing that a bay extended inland along the course of the stream. 
After this there is no well defined ridge for four miles westward, where it again commences, 
and continues without interruption nearly to Lewiston. All these facts are highly interesting, 
as showing its analogy to modern beaches along the lake shore, and the effects of streams 
flowing in from the higher grounds. 
In the town of Cambria, Niagara county, this ridge divides, or perhaps, more properly, we 
find a ridge diverging from the main one, and pursuing a northwesterly course for several 
miles, when it becomes merged in the general surrounding level. The main ridge, in the 
mean time, pursues its regular course, apparently uninfluenced by this diverging one. 
The following diagram illustrates the position of these ridges : 
1G9.® 
The smaller one is known as the “Little ridge,” from being less than the other; it is a 
single low well-defined ridge sloping uniformly on both sides, the country around being nearly 
level.t 
* See note under Modem lake ridges, page 356. 
t This feature of sloping on both sides, has been urged as an objection to the main ridge having been formed by the lake, as 
beaches are supposed to slope only seaward. Such, however, is not true either of lake or sea beaches, where they are formed 
before low or level ground ; there is always a ridge sloping inland, as well as seaward, and elevated in proportion to the force of 
the waves and its position with regard to accumulation of materials. I could cite an example on Massachusetts bay, where the 
sea has thrown up a beach for the distance of two miles, and from twenty to forty feet above its own level, completely damming 
out a large marsh about its own elevation. The water from this marsh finds its way into the bay by a circuit of ten or fifteen 
miles. Precisely similar were the operations in the formation of this ridge ; and analogous operations, only upon a smaller scale, 
are going on along the present lake shore. 
