The Irish standard., 1889-03-16
The Past and Future Of the Un-
paralleled Cataract.
Geological and Scientific Facts Concern
ing the Falls Collected by Prof. Julius
Pohlman-ChangesW Wrought With
in Forty-Five Years.

peologist OF New York. and all OF our exact
knowledge dates from his maps. Prof. Ha1
then gave the height of the American Fall
as 167 feet and of the Horseshoe Fall as 15S
feet, counting the elevations from the wa
ters' edge on October 4, 1912, and he admits
that this starting point can vary from four
to twenty feet with the rise and tall OF the
water below the Falls. He gave the width
Of the American Fall as 900 feet and that OF
the Horseshoe Fall as 1900 feet.
The Lake survey went over the ground
again in 1875, and in these thlrty-three years
the southernmost point Of the Horseshoe
Fall had roceded 100 feet while on the brink
of the American Fall differences OF forty
feet were apparent.
When the American Association for the
Advancement of Science met here in 1886
the section of geology decided to make
Niagara the problem of the session, and for
that purpose Prof Woodward, Of Washing
ton, and some of his assistants surveyed
the brink of the Falls again. They found
an average recession for the whole face OF
! the Falls of about two and one-half feet per
annum, but as the central parts OF the
curve, where the water is deepest. re-
treated faster than the edges, the southern
most point of the Horseshoe Fall was found
to have travelled south about 200 feet since
1875, or about 800 feet since 1912, nearly
nine feet every year. In view OF such rapid
changes it seems highly probable that the
older pictures of the Falls, which always
place the Horseshoe Fall considerably
nearer than they are to-day, are practically,
or at least partially correct.
| IF the rate of retrocession remains during
the next five hundred years as it has been
for the last forty-fve years, the inner edge
of the Horseshoe Fall will have passed to
the east of Goat Island, and as the line OF
deepest water is near the Canadian shore
all the waters Of the river will pass over
the Horseshoe Fall, celebrating the Amerl-
can fall entirely and Transforming Goat
island into peninsula, on which the
smaller islands OF to-day, Bath, Luna,
Chaplin, ETC., will appear as little hilltops.
The fall will then perhaps be higher than
to-day because the present descent OF hlty
feet over the rapids will be added to tho
height Of the cataract, minus the number Of
feet needed to give the necessary current
to the river below, which at present is hf-
teen feet to the mile. Considering that
even now the Horseshoe Fail no longer re-
cedes south but more east than south, which
recession will be more easterly yet in the
course of time, it will have to travel about
five miles in that direction before the Mag
ara shale, which now occupies the lower
/ half of the face Of the fall, is under water;
and the retrocession by means OF under
mining is stopped. For at present the
/, changes that take place are due to the fact
that the upper eighty feet of the face is
formed Of a hard limestone, while the
lower eighty feet is composed OF soft,
easily crumbling shale, which the spray
can wash away with ease to such an extent
that the everything limestones lose their sup
port, break off and tumble down with a cor
responding change in the appearance OF tho
edge of the falls. Then the changes will be
accomplished simply by the eroding power
of the water and the falls will remain near
the northern end of Grand Island Tor q
practically unlimited time. We thus SEQ
that after the falls Of today have receded,
perhaps three-quarters Of a mile, there
be only will one fall; when that one
fall has Travelled east and south
four miles more aud reaches Grand
Island, it will again be divided into
an American and Canadian cataract,
this time separated by Grand Island, and,
; like the falls of to-day, the western branch
/ will carry the largest amount OF water, VIII
recede faster and be the lower of the two in
height. The hope of finally having the falls
at Buffalo must be abandoned, fo. from that
point of Grand Island to the city of Buffalo
only rapids can exist OH account OF the nat
ure OF the underlying rock, which is soft.
As the retrocession of the Falls Of Niagara
began in what may be called, geologically,
the most recent period, the time necessary
for it to arrive at its present site has had a
very important bearing upon the question
of the age of man on the American con-
tinent AS long as it was considered nee
essary to claim several hundred Thousand
years for the age Of Niagara alone, the age
of the human race had to be computed at
perhaps half million Of years; no matter
how little such high figures agreed with
other discoveries, the rocky gorge Of the
Niagara always presented an insurmountar
BILE obstacle against any reduction Of time
But since we have discovered that after all
the work of excavation could have been ac~
, complished in perhaps 5000 years, our COM
putation of the age Of the human race has
settled down to reasonable figures, which
give to the beds of sand and gravel in which
the Oldest human implements have been
found an age of perhaps 10000 to 10000
years, and anthropologists claim that all the
/ facts so far collected agree we'll with the
latter figure.