Transcriber's Note
Italic text is denoted by _underscores_.
THE INTERNATIONAL SCIENTIFIC SERIES
VOLUME LXIX
THE
INTERNATIONAL SCIENTIFIC SERIES.
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* * * * *
[Illustration: CONTOUR AND GLACIAL MAP OF THE BRITISH ISLES]
THE INTERNATIONAL SCIENTIFIC SERIES
MAN AND
THE GLACIAL PERIOD
BY
G. FREDERICK WRIGHT
D. D., LL. D., F. G. S. A.
PROFESSOR IN OBERLIN THEOLOGICAL SEMINARY
FORMERLY ASSISTANT ON THE UNITED STATES GEOLOGICAL SURVEY
AUTHOR OF THE ICE AGE IN NORTH AMERICA.
LOGIC OF CHRISTIAN EVIDENCES, ETC.
_WITH AN APPENDIX ON TERTIARY MAN_
By PROF. HENRY W. HAYNES
FULLY ILLUSTRATED
_SECOND EDITION_
NEW YORK
D. APPLETON AND COMPANY
1895
Copyright, 1892,
By D. APPLETON AND COMPANY.
Electrotyped and Printed
at the Appleton Press, U. S. A.
TO
JUDGE C. C. BALDWIN
PRESIDENT OF THE WESTERN RESERVE HISTORICAL SOCIETY
CLEVELAND
THIS VOLUME IS DEDICATED
IN RECOGNITION OF
HIS SAGACIOUS AND UNFAILING INTEREST IN
THE INVESTIGATIONS WHICH HAVE MADE IT POSSIBLE
PREFACE TO THE SECOND EDITION.
Since, as stated in the Introduction (page 1), the plan of this volume
permitted only "a concise presentation of the facts," it was impossible
to introduce either full references to the illimitable literature of
the subject or detailed discussion of all disputed points. The facts
selected, therefore, were for the most part those upon which it was
supposed there would be pretty general agreement.
The discussion upon the subject of the continuity of the Glacial period
was, however, somewhat elaborate (see pages 106-121, 311, 324, 332),
and was presented with excessive respect for the authority of those who
maintain the opposite view; all that was claimed (page 110) being that
one might maintain the _unity_ or _continuity_ of the Glacial period
"without forfeiting his right to the respect of his fellow-geologists."
But it already appears that there was no need of this extreme modesty of
statement. On the contrary, the vigorous discussion of the subject which
has characterized the last two years reveals a decided reaction against
the theory that there has been more than one Glacial epoch in Quaternary
times; while there have been brought to light many most important if not
conclusive facts in favour of the theory supported in the volume.
In America the continuity of the Glacial period has been maintained
during the past two years with important new evidence, among others
by authorities of no less eminence and special experience in glacial
investigations than Professor Dana,[A] Mr. Warren Upham,[B] and Professor
Edward H. Williams, Jr.[C] Professor Williams's investigations on the
attenuated border of the glacial deposits in the Lehigh, the most
important upper tributary to the Delaware Valley, Pa., are of important
significance, since the area which he so carefully studied lies wholly
south of the terminal moraine of Lewis and Wright, and belongs to the
portion of the older drift which Professors Chamberlin and Salisbury
have been most positive in assigning to the first Glacial epoch, which
they have maintained was separated from the second epoch by a length of
time sufficient for the streams to erode rock gorges in the Delaware and
Lehigh Rivers from two hundred to three hundred feet in depth.[D] But
Professor Williams has found that the rock gorges of the Lehigh, and
even of its southern tributaries, had been worn down approximately to
the present depth of that of the Delaware before this earliest period of
glaciation, and that the gorges were filled with the earliest glacial
_débris_.
[Footnote A: American Journal of Science, vol. xlvi, pp. 327, 330.]
[Footnote B: American Journal of Science, vols, xlvi, pp. 114-121; xlvii,
pp. 358-365; American Geologist, vols, x, pp. 339-362, especially pp.
361, 362; xiii, pp. 114, 278; Bulletin of the Geological Society of
America, vol. v, pp. 71-86, 87-100.]
[Footnote C: Bulletin of the Geological Society of America, vol. v, pp.
13-16, 281-296; American Journal of Science, vol. xlvii, pp. 33-36.]
[Footnote D: See especially Chamberlin, in the American Journal of
Science, vol. xlv, p. 192; Salisbury, in the American Geologist, vol. xi,
p. 18.]
A similar relation of the glacial deposits of the attenuated border to
the preglacial erosion of the rock gorges of the Alleghany and upper
Ohio Rivers has been brought to light by the joint investigations of Mr.
Frank Leverett and myself in western Pennsylvania, in the vicinity of
Warren, Pa., where, in an area which was affected by only the earliest
glaciation, glacial deposits are found filling the rock channels of
old tributaries to the Alleghany to a depth of from one hundred and
seventy to two hundred and fifty feet, and carrying the preglacial
erosion at that point very closely, if not quite, down to the present
rock bottoms of all the streams. This removes from Professor Chamberlin
a most important part of the evidence of a long interglacial period to
which he had appealed; he having maintained[E] that "the higher glacial
gravels antedated those of the moraine-forming epoch by the measure of
the erosion of the channel through the old drift and the rock, whose mean
depth here is about three hundred feet, of which perhaps two hundred and
fifty feet may be said to be rock," adding that the "excavation that
intervened between the two epochs in other portions of the Alleghany,
Monongahela, and upper Ohio valleys is closely comparable with this."
[Footnote E: Bulletin 58 of the United States Geological Survey, p. 35;
American Journal of Science, vol. xlv, p. 195.]
These observations of Mr. Leverett and myself seem to demonstrate the
position maintained in the volume (page 218), namely, that the inner
precipitous rock gorges of the upper Ohio and its tributaries are mainly
_pre_glacial, rather than _inter_glacial. The only way in which Professor
Chamberlin can in any degree break the force of this discovery is by
assuming that in preglacial times the present narrow rock gorges of the
Alleghany and the Ohio were not continuous, but that (as indicated in
the present volume on page 206) the drainage of various portions of that
region was by northern outlets to the Lake Erie basin, leaving, on this
supposition, the _cols_ between two or three drainage areas to be lowered
in glacial or interglacial time.
On the theory of continuity the erosion of these _cols_ would have been
rapidly effected by the reversed drainage consequent upon the arrival
of the ice-front at the southern shore of the Lake Erie basin. During
all the time elapsing thereafter, until the ice had reached its southern
limit, the stream was also augmented by the annual partial melting of
the advancing glacier which was constantly bringing into the valley
the frozen precipitation of the far north. The distance is from thirty
to seventy miles, so that a moderately slow advance of the ice at that
stage would afford time for a great amount of erosion before sufficient
northern gravel had reached the region to begin the filling of the
gorge.[F]
[Footnote F: See an elaborate discussion of the subject in its new phases
by Chamberlin and Leverett, in the American Journal of Science, vol.
xlvii, pp. 247-283.]
Mr. Leverett also presented an important paper before the Geological
Society of America at its meeting at Madison, Wis., in August, 1893,
adducing evidence which, he thinks, goes to prove that the post-glacial
erosion in the earlier drift in the region of Rock River, Ill., was
seven or eight times as much as that in the later drift farther north;
while Mr. Oscar H. Hershey arrives at nearly the same conclusions from
a study of the buried channels in northwestern Illinois.[G] But even
if these estimates are approximately correct--which is by no means
certain--they only prove the length of the Glacial period, and not
necessarily its discontinuity.
[Footnote G: American Geologist, vol. xii, p. 314f. Other important
evidence to a similar effect is given by Mr. Leverett, in an article on
The Glacial Succession in Ohio, Journal of Geology, vol. i, pp. 129-146.]
At the same time it should be said that these investigations in western
Pennsylvania somewhat modify a portion of the discussion in the present
volume concerning the effects of the Cincinnati ice-dam. It now appears
that the full extent of the gravel terraces of glacial origin in the
Alleghany River had not before been fully appreciated, since they are
nearly continuous on the two-hundred-foot rock shelf, and are often
as much as eighty feet thick. It seems probable, therefore, that the
Alleghany and upper Ohio gorge was filled with glacial gravel to a depth
of about two hundred and fifty or three hundred feet, as far down at
least as Wheeling, W. Va. If this was the case, it would obviate the
necessity of bringing in the Cincinnati ice-dam (as set forth in pages
212-216) to account directly for all the phenomena in that region, except
as this obstruction at Cincinnati would greatly facilitate the silting up
of the gorge. The simple accumulation of glacial gravel in the Alleghany
gorge would of itself dam up the Monongahela at Pittsburg, so as to
produce the results detailed by Professor White on page 215.[H]
[Footnote H: For a full discussion of these topics, see paper by
Professor B. C. Jillson, Transactions of the Academy of Science and
Art of Pittsburg, December 8, 1893; G. F. Wright, American Journal of
Science, vol. xlvii, pp. 161-187; especially pp. 177, 178; The Popular
Science Monthly, vol. xlv, pp. 184-198.]
Of European authorities who have recently favoured the theory of the
continuity of the Quaternary Glacial period, as maintained in the volume,
it is enough to mention the names of Prestwich,[I] Hughes,[J] Kendall,[K]
Lamplugh,[L] and Wallace,[M] of England; Falsan,[N] of France; Holst,[O]
of Sweden; Credner[P] and Diener,[Q] of Germany; and Nikitin[R] and
Kropotkin,[S] of Russia.[T] Among leading authorities still favouring a
succession of Glacial epochs are: Professor James Geikie,[U] of Scotland;
Baron de Geer,[V] of Sweden; and Professor Felix Wahnschaffe,[W] of
Germany.
[Footnote I: Quarterly Journal of the Geological Society for August,
1887.]
[Footnote J: American Geologist, vol. viii, p. 241.]
[Footnote K: Transactions of the Leeds Geological Association for
February 10, 1893.]
[Footnote L: Quarterly Journal of the Geological Society, August, 1891.]
[Footnote M: Fortnightly Review, November, 1893, p. 633; reprinted in The
Popular Science Monthly, vol. xliv, p. 790.]
[Footnote N: La Période glaciaire (Félix Alcan. Paris, 1889).]
[Footnote O: American Geologist, vol. viii, p. 242.]
[Footnote P: Ibid., p. 241.]
[Footnote Q: Ibid., p. 242.]
[Footnote R: Congrès International d'Archéologie, Moscow, 1892.]
[Footnote S: Nineteenth Century, January, 1894, p. 151, note.]
[Footnote T: The volume The Glacial Geology of Great Britain and Ireland,
edited from the unpublished MSS. of the late Henry Carvill Lewis (London,
Longmans, Green & Co., 1894), adds much important evidence in favour of
the continuity of the Glacial epoch; see especially pp. 187, 460, 461,
466.]
[Footnote U: Transactions of the Royal Society of Edinburgh, vol. xxxvii,
Part I, pp. 127-150.]
[Footnote V: American Geologist, vol. viii, p. 246.]
[Footnote W: Forschungen zur deutschen Landes und Volkskunde von Dr. A.
Kirchhoff. Bd. vi, Heft i.]
When the first edition was issued, two years ago, there seemed to be
a general acceptance of all the facts detailed in it which directly
connected man with the Glacial period both in America and in Europe;
and, indeed, I had studiously limited myself to such facts as had been
so long and so fully before the public that there would seem to be no
necessity for going again into the details of evidence relating to them.
It appears, however, that this confidence was ill-founded; for the
publication of the book seems to have been the signal for a confident
challenge, by Mr. W. H. Holmes, of all the American evidence, with
intimations that the European also was very likely equally defective.[X]
In particular Mr. Holmes denies the conclusiveness of the evidence of
glacial man adduced by Dr. Abbott and others at Trenton, N. J.; Dr.
Metz, at Madisonville, Ohio; Mr. Mills, at Newcomerstown, Ohio; and Miss
Babbitt, at Little Falls, Minn.
[Footnote X: Journal of Geology, vol. i, pp. 15-37, 147-163; American
Geologist, vol. xi, pp. 219-240.]
The sum of Mr. Holmes's effort amounts, however, to little more than
the statement that, with a limited amount of time and labour, neither he
nor his assistants had been able to find any implements in undisturbed
gravel in any of these places; and the suggestion of various ways in
which he thinks it possible that the observers mentioned may have been
deceived as to the original position of the implements found. But, as
had been amply and repeatedly published,[Y] Professor J. D. Whitney,
Professor Lucien Carr, Professor N. S. Shaler, Professor F. W. Putnam,
of Harvard University, besides Dr. C. C. Abbott, all expressly and with
minute detail describe finding implements in the undisturbed gravel at
Trenton, which no one denies to be of glacial origin. In the face of
such testimony, which had been before the public and freely discussed
for several years, it is an arduous undertaking for Mr. Holmes to claim
that none of the implements have been found in place, because he and
his assistants (whose opportunities for observation had scarcely been
one twentieth part as great as those of the others) failed to find any.
To see how carefully the original observations were made, one has but
to read the reports to Professor Putnam which have from time to time
appeared in the Proceedings of the Peabody Museum and of the Boston
Society of Natural History,, and which are partially summed up in the
thirty-second chapter of Dr. Abbott's volume on Primitive Industry.
[Footnote Y: Proceedings of the Boston Society of Natural History, vol.
xxi, January 19, 1881; Report of the Peabody Museum, vol. ii, pp. 44-47;
chap, xxxii of Abbott's Primitive Industry; American Geologist, vol. xi,
pp. 180-184.]
In the case of the discovery at Newcomerstown, Mr. Holmes is peculiarly
unfortunate in his efforts to present the facts, since, in endeavouring
to represent the conditions under which the implement was found by Mr.
Mills, he has relied upon an imaginary drawing of his own, in which an
utterly impossible state of things is pictured. The claim of Mr. Holmes
in this case, as in the other, is that possibly the gravel in which the
implements were found had been disturbed. In some cases, as in Little
Falls and at Madison ville, he thinks the implements may have worked down
to a depth of several feet by the overturning of trees or by the decay
of the tap-root of trees. A sufficient answer to these suggestions is,
that Mr. Holmes is able to find no instance in which the overturning of
trees has disturbed the soil to a depth of more than three or four feet,
while some of the implements in these places had been found buried from
eight to sixteen feet. Even if, as Mr. Chamberlin suggests,[Z] fifty
generations of trees have decayed on the spot since the retreat of the
ice, it is difficult to see how that would help the matter, since the
effect could not be cumulative, and fifty upturnings of three or four
feet would not produce the results of one upturning of eight feet.
Moreover, at Trenton, where the upturning of trees and the decaying of
tap-roots would have been as likely as anywhere to bury implements,
none of those of flint or jasper (which occur upon the surface by tens
of thousands) are buried more than a foot in depth; while the argillite
implements occur as low down as fifteen or twenty feet. This limitation
of flint and jasper implements to the surface is conclusively shown not
only by Dr. Abbott's discoveries, but also by the extensive excavations
at Trenton of Mr. Ernest Volk, whose collections formed so prominent
a part of Professor Putnam's Palæolithic exhibit at the Columbian
Exposition at Chicago. In the village sites explored by Mr. Volk,
argillite was the exclusive material of the implements found in the lower
strata of gravel. Similar results are indicated by the excavations of Mr.
H. C. Mercer at Point Pleasant, Pa., about twenty miles above Trenton,
where, in the lower strata, the argillite specimens are sixty-one times
more numerous than the jasper are.
[Footnote Z: American Geologist, vol. xi, p. 188.]
To discredit the discoveries at Trenton and Newcomerstown, Mr. Holmes
relies largely upon the theory that portions of gravel from the surface
had slid down to the bottom of the terrace, carrying implements with
them, and forming a talus, which, he thinks, Mr. Mills, Dr. Abbott,
and the others have mistaken for undisturbed strata of gravel. In his
drawings Mr. Holmes has even represented the gravel at Newcomerstown
as caving down into a talus without disturbing the strata to any great
extent, and at the same time he speaks slightingly of the promise which I
had made to publish a photograph of the bank as it really was. In answer,
it is sufficient to give, first, the drawing made at the time by Mr.
Mills, to show the general situation of the gravel bank at Newcomerstown,
in which the implement figured on page 252 was found; and, secondly, an
engraving from a photograph of the bank, taken by Mr. Mills after the
discovery of the implement, but before the talus had obscured its face.
The implement was found by Mr. Mills with its point projecting from a
fresh exposure of the terrace, just after a mass, loosened by his own
efforts, had fallen away. The gravel is of such consistency that every
sign of stratification disappears when it falls down, and there could be
no occasion for a mistake even by an ordinary observer, while Mr. Mills
was a well-trained geologist and collector, making his notes upon the
spot.[AA]
[Footnote AA: The Popular Science Monthly, vol. xliii, pp. 29-39.]
[Illustration: Height of Terrace exposed, 25 feet. Palæolith was found
14-3/4 feet from surface.]
[Illustration: Terrace in Newcomerstown, showing where W. C. Mills found
the Palæolithic implement.]
I had thought at first that Mr. Holmes had made out a better case against
the late Miss Babbitt's discoveries at Little Falls (referred to on
page 254), but in the American Geologist for May, 1894, page 363, Mr.
Warren Upham, after going over the evidence, expresses it as still his
conviction that Mr. Holmes's criticism fails to shake the force of the
original evidence, so that I do not see any reason for modifying any of
the statements made in the body of the book concerning the implements
supposed to have been found in glacial deposits. Yet if I had expected
such an avalanche of criticism of the evidence as has been loosened, I
should at the time have fortified my statements by fuller references,
and should possibly have somewhat enlarged the discussion. But this
seemed then the less necessary, from the fact that Mr. McGee had, in most
emphatic manner, indorsed nearly every item of the evidence adduced by
me, and much more, in an article which appeared in The Popular Science
Monthly four years before the publication of the volume (November, 1888).
In this article he had said:
"But it is in the aqueo-glacial gravels of the Delaware River at Trenton,
which were laid down contemporaneously with the terminal moraine one
hundred miles farther northward, and which have been so thoroughly
studied by Abbott, that the most conclusive proof of the existence of
glacial man is found" (p. 23). "Excluding all doubtful cases, there
remains a fairly consistent body of testimony indicating the existence of
a widely distributed human population upon the North. American continent
during the later Ice epoch" (p. 24). "However the doubtful cases may be
neglected, the testimony is cumulative, parts of it are unimpeachable,
and the proof of the existence of glacial man seems conclusive" (p. 25).
In view of the grossly erroneous statements made by Mr. McGee concerning
the Nampa image (described on pages 298, 299), it is necessary for
me to speak somewhat more fully of this important discovery. The
details concerning the evidence were drawn out by me at length in two
communications to the Boston Society of Natural History (referred to on
page 297), which fill more than thirty pages of closely printed matter,
while two or three years before the appearance of the volume the facts
had been widely published in the New York Independent, the Scientific
American, The Nation, Scribner's Magazine, and the Atlantic Monthly,
and in Washington at a meeting of the Geological Society of America
in 1890. In the second communication to the Boston Society of Natural
History an account was given of a personal visit to the Snake River
Valley, largely for the purpose of further investigation of the evidence
brought to my notice by Mr. Charles Francis Adams, and of the conditions
under which the figurine was found. Among the most important results
of this investigation was the discovery of numerous shells under the
lava deposits, which Mr. Dall, of the United States Geological Survey,
identified for me as either post-Tertiary or late Pliocene; thus throwing
the superficial lava deposits of the region into the Quaternary period,
and removing from the evidence the antecedent improbability which would
bear so heavily against it if we were compelled to suppose that the
lava of the Snake River region was all of Tertiary or even of early
Quaternary age. Furthermore, the evidence of the occurrence of a great
_débâcle_ in the Snake River Valley during the Glacial period, incident
upon the bursting of the banks of Lake Bonneville, goes far to remove
antecedent presumptions against the occurrence of human implements in
such conditions as those existing at Nampa (see below, pp. 233-237).
Mr. McGee's misunderstanding of the evidence on one point is so gross,
that I must make special reference to it. He says[AB] that this image
"is alleged to have been pounded out of volcanic tuff by a heavy drill,
... under a thick Tertiary lava bed." The statement of facts on page
298 bears no resemblance to this representation. It is there stated
that there were but fifteen feet of lava, and that near the surface;
that below this there was nothing but alternating beds of clay and
quicksand, and that the lava is post-Tertiary. The sand-pump I should
perhaps have described more fully in the book, as I had already done in
the communication to the Boston Society of Natural History. It was a
tube eight feet long, with a valve at the bottom three and a half inches
in diameter on the inside. Through this it was the easiest thing in the
world for the object, which is only one inch and a half long, to be
brought up in the quicksand without injury.
[Footnote AB: Literary Northwest, vol. ii, p. 275.]
The baseless assertions of Mr. McGee, involving the honesty of Messrs.
Kurtz and Duffes, are even less fortunate and far more reprehensible. "It
is a fact," says Mr. McGee, "that one of the best-known geologists of the
world chanced to visit Nampa while the boring was in progress, and the
figurine and the pretty fiction were laid before him. He recognized the
figurine as a toy such as the neighbouring Indians give their children,
and laughed at the story; whereupon the owner of the object enjoined
secrecy, pleading: 'Don't give me away; I've fooled a lot of fellows
already, and I'd like to fool some more.'"[AC] This well-known geologist,
on being challenged by Professor Claypole[AD] to give "a full, exact,
and certified statement of the conversation" above referred to, proved
to be Major Powell, who responded with the following statement: "In the
fall of 1889 the writer visited Boise City, in Idaho [twenty miles from
Nampa]. While stopping at a hotel, some gentlemen called on him to show
him a figurine which they said they had found in sinking an artesian
well in the neighbourhood, at a depth, if I remember rightly, of more
than three hundred feet.... When this story was told the writer, he
simply jested with those who claimed to have found it. He had known the
Indians that live in the neighbourhood, had seen their children play with
just such figurines, and had no doubt that the little image had lately
belonged to some Indian child, and said the same. While stopping at the
hotel different persons spoke about it, and it was always passed off as
a jest; and various comments were made about it by various people, some
of them claiming that it had given them much sport, and that a good many
tenderfeet had looked at it, and believed it to be genuine; and they
seemed rather pleased that I had detected the hoax."[AE]
[Footnote AC: American Anthropologist, vol. vi, p. 94: repeated by Mr.
McGee in the Literary Northwest, vol. ii, p. 276.]
[Footnote AD: The Popular Science Monthly, vol. xlii, p. 773.]
[Footnote AE: Ibid., vol. xliii, pp. 322, 323.]
Thus it appears that Major Powell has made no such statement, at least
in public, as Mr. McGee attributes to him. It should be said, also, that
Major Powell's memory is very much at fault when he affirms that there
is a close resemblance between this figurine and some of the children's
playthings among the Pocatello Indians. On the contrary, it would have
been even more of a surprise to find it in the hands of these children
than to find it among the prehistoric deposits on the Pacific coast.
To most well-informed people it is sufficient to know that no less
high authorities than Mr. Charles Francis Adams and Mr. G. M. Gumming,
General Manager for the Union Pacific line for that district, carefully
investigated the evidence at the time of the discovery, and, knowing
the parties, were entirely satisfied with its sufficiency. It was
also subjected to careful examination by Professor F. W. Putnam, who
discerned, in a deposit of an oxide of iron on various parts of the
image, indubitable evidence that it was a relic which had lain for a long
time in some such condition as was assigned to it in the bottom of the
well--all of which is detailed in the papers referred to below, on page
297.
Finally, the discovery, both in its character and conditions, is in so
many respects analogous to those made under Table Mountain, near Sonora,
Cal. (described on pages 294-297), that the evidence of one locality adds
cumulative force to that of the other. The strata underneath the lava in
which these objects were found are all indirectly, but pretty certainly,
connected with the Glacial period.[AF] No student of glacial archæology,
therefore, can hereafter afford to disregard these facts from the Pacific
coast.
[Footnote AF: See below, p. 349.]
Oberlin, Ohio, _June 2, 1894_.
PREFACE TO THE FIRST EDITION.
The wide interest manifested in my treatise upon The Ice Age in North
America and its Bearing upon the Antiquity of Man (of which a third
edition was issued a year ago), seemed to indicate the desirability of
providing for the public a smaller volume discussing the broader question
of man's entire relation to the Glacial period in Europe as well as in
America. When the demand for such a volume became evident, I set about
preparing for the task by spending, first, a season in special study
of the lava-beds of the Pacific coast, whose relations to the Glacial
period and to man's antiquity are of such great interest; and, secondly,
a summer in Europe, to enable me to compare the facts bearing upon the
subject on both continents.
Of course, the chapters of the present volume relating to America cover
much of the same ground gone over in the previous treatise; but the
matter has been entirely rewritten and very much condensed, so as to give
due proportions to all parts of the subject. It will interest some to
know that most of the new material in this volume was first wrought over
in my second course of Lowell Institute Lectures, given in Boston during
the month of March last.
I am under great obligations to Mr. Charles Francis Adams for his aid in
prosecuting investigations upon the Pacific coast of America; and also to
Dr. H. W. Crosskey, of Birmingham, England, and to Mr. G. W. Lamplugh,
of Bridlington, as well as to Mr. C. E. De Rance and Mr. Clement Reid,
of the British Geological Survey, besides many others in England who
have facilitated my investigations; but pre-eminently to Prof. Percy F.
Kendall, of Stockport, who consented to prepare for me the portion of
Chapter VI which relates to the glacial phenomena of the British Isles. I
have no doubt of the general correctness of the views maintained by him,
and little doubt, also, that his clear and forcible presentation of the
facts will bring about what is scarcely less than a revolution in the
views generally prevalent relating to the subject of which he treats.
For the glacial facts relating to France and Switzerland I am indebted
largely to M. Falsan's valuable compendium, La Période Glaciaire.
It goes without saying, also, that I am under the deepest obligation
to the works of Prof. James Geikie upon The Great Ice Age and upon
Prehistoric Europe, and to the remarkable volume of the late Mr. James
Croll upon Climate and Time, as well as to the recent comprehensive
geological treatises of Sir Archibald Geikie and Prof. Prestwich.
Finally, I would express my gratitude for the great courtesy of Prof.
Fraipont, of Liége, in assisting me to an appreciation of the facts
relating to the late remarkable discovery of two entire skeletons of
Paleolithic man in the grotto of Spy.
Comparative completeness is also given to the volume by the appendix on
the question of man's existence during the Tertiary period, prepared by
the competent hand of Prof. Henry W. Haynes, of Boston.
I trust this brief treatise will be useful not only in _interesting_
the general public, but in giving a clear view of the present state of
progress in one department of the inquiries concerning man's antiquity.
If the conclusions reached are not as positive as could be wished, still
it is both desirable and important to see what degree of indefiniteness
rests upon the subject, in order that rash speculations may be avoided
and future investigations directed in profitable lines.
G. Frederick Wright.
Oberlin, Ohio, _May 1, 1892_.
CONTENTS.
PAGES
CHAPTER I.
Introductory 1-8
CHAPTER II.
Existing Glaciers 9-42
In Europe; in Asia; in Oceanica; in South America;
on the Antarctic Continent; in North America.
CHAPTER III.
Glacial Motion 43-50
CHAPTER IV.
Signs of Past Glaciation 51-65
CHAPTER V.
Ancient Glaciers in the Western Hemisphere 66-128
New England; New York, New Jersey, and Pennsylvania;
the Mississippi Basin; west of the Rocky Mountains.
CHAPTER VI.
Ancient Glaciers in the Eastern Hemisphere 129-192
Central and Southern Europe; the British Isles--the
Preglacial Level of the Land, the Great Glacial Centres,
the Confluent Glaciers, the East Anglian Glacier,
the so-called Great Submergence; Northern Europe;
Asia; Africa.
CHAPTER VII.
Drainage Systems in the Glacial Period 193-241
In America--Preglacial Erosion, Buried Outlets and
Channels, Ice-dams, Ancient River Terraces; in Europe.
CHAPTER VIII.
Relics of Man in the Glacial Period 242-301
In Glacial Terraces of the United States; in Glacial
Terraces of Europe; in Cave Deposits in the British
Isles; in Cave Deposits on the Continent; Extinct
Animals associated with Man; Earliest Man on the
Pacific Coast of North America.
CHAPTER IX.
The Cause of the Glacial Period 302-331
CHAPTER X.
The Date of the Glacial Period 332-364
Appendix on the Tertiary Man 365-374
Index 375-385
LIST OF ILLUSTRATIONS.
FIG. PAGE
1. Zermatt Glacier 2
2. Formation of veined structure 3
3, 4. Formation of marginal fissures and veins 4
5. Fissures and seracs 4
6. Section across glacial valley, showing old lateral moraines 5
7. Mont Blanc glacier region 10
8. Svartisen Glacier 13
9. Floating berg 18
10. Iceberg in the Antarctic Ocean 20
11. Map of southeastern Alaska 22
12. Map of Glacier Bay, Alaska 25
13. Front of Muir Glacier 26
14. Map of glaciers in the St. Elias Alps 31
15. Map of Greenland 33
16. Diagram showing the character of glacial motion 43
17. Line of most rapid glacial motion 45
18. Diagram showing retardation of the bottom of a glacier 46
19. Bed-rock scored with glacial marks 52
20. Scratched stone from the till of Boston 54
21. Typical section of till in Seattle, Wash. 55
22. Ideal section showing how the till overlies the stratified
rocks 56
23. Vessel Rock, a glacial boulder 56
24. Map of Rhône Glacier 58
25. Conglomerate boulder found in Boone County, Ky. 63
26. Mohegan Rock 72
27. Drumlins in Goffstown, N. H. 73
28. Map of drumlins in the vicinity of Boston 75
29. Section of kame 77
30. Map of kames in Andover, Mass. 78
31. Longitudinal kames near Hingham, Mass. 79
32. Map showing the kames of Maine and southeastern New Hampshire 81
33. Western face of the Kettle Moraine near Eagle, Wis. 99
34. Section of the east-and-west glacial furrows on Kelly's
Island 103
35. Same as the preceding 105
36. Section of till near Germantown, Ohio 108
37. Moraines of Grape Creek, Col. 123
38. Map of North America in the Ice period 127
39. Quartzite boulder on Mont Lachat 128
40. Map showing glaciated areas in North America and Europe 130
41. Maps showing lines of _débris_ extending from the Alps into
the plains of the Po 134
42. Section of the Cefn Cave 148
43. Map showing moraine between Speeton and Flamborough 156
44. Diagram-section near Cromer 166
45. Section through the westerly chalk bluff at Trimingham,
Norfolk 162
46. Section across Wales 172
47. Section of cliff at Flamborough Head 176
48. Enlarged section of the shelly sand and surrounding clay
at _B_ in preceding figure 177
49. Map showing the glaciated area of Europe 184
50. Map showing old channel and mouth of the Hudson 195
51. New York Harbor in preglacial times 197
52. Section across the valley of the Cuyahoga River 200
53. Map of Mississippi River from Fort Snelling to Minneapolis 209
54. Map showing the effect of the glacial dam at Cincinnati 213
55. Map of Lake Erie-Ontario 219
56. Map of Cuyahoga Lake 221
57. Section of the lake ridges near Sandusky, Ohio 223
58. Map showing stages of recession of the ice in Minnesota 225
59. Glacial terrace on Raccoon Creek, in Ohio 227
60. Ideal section across a river-bed in drift region 229
61. Map of Lakes Bonneville and Lahontan 234
62. Parallel roads of Glen Roy 239
63. Map showing glacial terraces on the Delaware and
Schuylkill Rivers 243
64. Palæolith found by Abbott in New Jersey 244
65. Section across the Delaware River at Trenton, N. J. 245
66. Section of the Trenton gravel 246
67. Face view of argillite implement found by Dr. C. C. Abbott
in 1876. 247
68. Argillite implement found by Dr. C. C. Abbott, March, 1879 248
69. Chipped pebble of black chert found by Dr. C. L. Metz,
October, 1885 249
70. Map showing glaciated area in Ohio 250
71. Palæoliths from Newcomerstown and Amiens (face view) 252
72. Edge view of the preceding 253
73. Section across the Mississippi Valley at Little Falls, Minn. 254
74. Quartz implement found by Miss F. E. Babbitt, 1878, at Little
Falls, Minn 255
75. Argillite implement found by H. T. Cresson, 1887 259
76. General view of Baltimore and Ohio Railroad cut,
Claymont, Del. 260
77. Section across valley of the Somme 262
78. Mouth of Kent's Hole 268
79. Engis skull (reduced) 274
80. Comparison of forms of skulls 276
81. Skull of the Man of Spy 277
82. Tooth of Machairodus neogæus 281
83. Perfect tooth of an Elephas 281
84. Skull of Hyena spelæa 282
85. Celebrated skeleton of mammoth in St. Petersburg Museum 283
86. Molar tooth of mammoth 284
87. Tooth of Mastodon Americanus 284
88. Skeleton of Mastodon Americanus 286
89. Skeleton of Rhinoceros tichorhinus 287
90. Skull of cave-bear 287
91. Skeleton of the Irish elk 288
92. Musk-sheep 289
93. Reindeer 290
94. Section across Table Mountain, Tuolumne County, Cal. 294
95. Calaveras skull 295
96. Three views of Nampa image, drawn to scale 298
97. Map showing Pocatello, Nampa, and the valley of Snake River 299
98. Section across the channel of the Stanislaus River 300
99. Diagram showing effect of precession 308
100. Map showing course of currents in the Atlantic Ocean 314
101. Map showing how the land clusters about the north pole 319
102. Diagram showing oscillations of land-surface and ice-surface
during the Glacial epoch 323
103. Diagram of eccentricity and precession 333
104. Map of the Niagara River below the Falls 334
105. Section of strata along the Niagara Gorge 336
106. Map showing the recession of the Horseshoe Falls since 1842 338
107. Section of kettle-hole near Pomp's Pond, Andover, Mass. 345
108. Flint-flakes collected by Abbé Bourgeois 368
MAPS.
TO FACE PAGE
Contour and glacial map of the British Isles _Frontispiece._
Map showing the glacial geology of the United States 66
Map of glacial movements in France and Switzerland 132
MAN AND THE GLACIAL PERIOD.
CHAPTER I.
INTRODUCTORY.
That glaciers now exist in the Alps, in the Scandinavian range, in
Iceland, in the Himalayas, in New Zealand, in Patagonia, and in the
mountains of Washington, British Columbia, and southeastern Alaska, and
that a vast ice-sheet envelops Greenland and the Antarctic Continent,
are statements which can be verified by any one who will take the
trouble to visit those regions. That, at a comparatively recent date,
these glaciers extended far beyond their present limits, and that others
existed upon the highlands of Scotland and British America, and at one
time covered a large part of the British Isles, the whole of British
America, and a considerable area in the northern part of the United
States, are inferences drawn from phenomena which are open to every one's
observations. That man was in existence and occupied both Europe and
America during this great expansion of the northern glaciers is proved
by evidence which is now beyond dispute. It is the object of the present
volume to make a concise presentation of the facts which have been
rapidly accumulating during the past few years relating to the Glacial
period and to its connection with human history.
Before speaking of the number and present extent of existing glaciers,
it will be profitable, however, to devote a little attention to the
definition of terms.
[Illustration: Fig. 1.--Zermatt Glacier (Agassiz).]
A _glacier_ is a mass of ice so situated and of such size as to have
motion in itself. The conditions determining the character and rate
of this motion will come up for statement and discussion later. It is
sufficient here to say that ice has a capacity of movement similar to
that possessed by such plastic substances as cold molasses, wax, tar, or
cooling lava.
The limit of a glacier's _motion_ is determined by the forces which fix
the point at which its final melting takes place. This will therefore
depend upon both the warmth of the weather and upon the amount of ice.
If the ice is abundant, it will move farther into the region of warm
temperature than it will if it is limited in supply.
Upon ascending a glacier far enough, one reaches a comparatively
motionless part corresponding to the lake out of which a river often
flows. Technically this is called the _névé_.
_Glacial ice_ is formed from snow where the annual fall is in excess
of the melting power of the sun at that point. Through the influence
of pressure, such as a boy applies to a snow-ball (but which in the
_névé_-field arises from the weight of the accumulating mass), the lower
strata of the _névé_ are gradually transformed into ice. This process, is
also assisted by the moisture which percolates through the snowy mass,
and which is furnished both by the melting of the surface snow and by
occasional rains.
The division between the _névé_ and the glacier proper is not always
easily determined. The beginnings of the glacial movement--that is, of
the movement of the ice-stream flowing out of the _névé_-field--are
somewhat like the beginnings of the movement of the water from a great
lake into its outlet. The _névé_ is the reservoir from which the glacier
gets both its supply of ice and the impulse which gives it its first
movement. There can not be a glacier without a _névé_-field, as there can
not be a river without a drainage basin. But there may be a _névé_-field
without a glacier--that is, a basin may be partially filled with snow
which never melts completely away, while the equilibrium of forces is
such that the ice barely reaches to the outlet from which the tongue-like
projection (to which the name glacier would be applied) fails to emerge
only because of the lack of material.
[Illustration: Fig. 2.--Illustrates the formation of veined structure by
pressure at the junction of two branches.]
A glacier is characterised by both _veins_ and _fissures_. The veins
give it a banded or stratified appearance, blue alternating with
lighter-coloured portions of ice. As these bands are not arranged with
any apparent uniformity in the glacier, their explanation has given
rise to much discussion. Sometimes the veins are horizontal, sometimes
vertical, and at other times at an angle with the line of motion. On
close investigation, however, it is found that the veins are always
at right angles to the line of greatest pressure. This leads to the
conclusion that pressure is the cause of the banded structure. The
blue strata in the ice are those from which the particles of air have
been expelled by pressure; the lighter portions are those in which the
particles are less thoroughly compacted. Snow is but pulverized ice, and
differs in colour from the compact mass for the same reason that almost
all rocks and minerals change their colour when ground into a powder.
[Illustration: Figs. 3, 4.--Illustrate the formation of marginal fissures
and veins.]
[Illustration: Fig. 5.--_c_, _c_, show fissures and seracs where the
glacier moves down the steeper portion of its incline; _s_, _s_, show the
vertical structure produced by pressure on the gentler slopes.]
The _fissures_, which, when of large size, are called _crevasses_, are
formed in those portions of a glacier where, from some cause, the ice
is subjected to slight tension. This occurs especially where, through
irregularities in the bottom, the slope of the descent is increased. The
ice, then, instead of moving in a continuous stream at the top, cracks
open along the line of tension, and wedge-shaped fissures are formed
extending from the top down to a greater or less distance, according to
the degree of tension. Usually, however, the ice remains continuous in
the lower strata, and when the slope is diminished the pressure reunites
the faces of the fissure, and the surface becomes again comparatively
smooth. Where there are extensive areas of tension, the surface of the
ice sometimes becomes exceedingly broken, presenting a tangled mass of
towers, domes, and pinnacles of ice called _seracs_.
[Illustration: Fig. 6.--Section across Glacial Valley, showing old
Lateral Moraines.]
Like running water, moving ice is a powerful agent in _transporting_
rocks and earthy _débris_ of all grades of fineness; but, owing to the
different consistencies of ice and water, there are great differences in
the mode and result of transportation by them. While water can hold in
suspension only the very finest material, ice can bear upon its surface
rocks of the greatest magnitude, and can roll or shove along under it
boulders and pebbles which would be Unaffected except by torrential
currents of water. We find, therefore, a great amount of earthy material
of all sizes upon the top of a glacier, which has reached it very much as
_débris_ reaches the bed of a river, namely, by falling down upon it from
overhanging cliffs, or by land-slides of greater or less extent. Such
material coming into a river would either disappear beneath its surface,
or would form a line of _débris_ along the banks; in both cases awaiting
the gradual erosion and transportation which running water is able to
effect. But, in case of a glacier, the material rests upon the surface of
the ice, and at once begins to partake of its motion, while successive
accessions of material keep up the supply at any one point, so as to form
a train of boulders and other _débris_, extending below the point as far
as the glacial motion continues.
Such a line of _débris_ is called a _moraine_. When it forms along the
edge of the ice, it is called a _lateral_ moraine. It is easy to see
that, where glaciers come out from two valleys which are tributary to
a larger valley, their inner sides must coalesce below the separating
promontory, and the two lateral moraines will become united and will
move onward in the middle of the surface of the glacier. Such lines of
_débris_ are called _medial_ moraines. These are characteristic of all
extensive glaciers formed by the union of tributaries. There is no limit
to the number of medial moraines, except in the number of tributaries.
A medial moraine, when of sufficient thickness, protects the ice
underneath it from melting; so that the moraine will often appear to
be much larger than it really is: what seems to be a ridge of earthy
material being in reality a long ridge of ice, thinly covered with earthy
_débris_, sliding down the slanting sides as the ice slowly wastes away
Large blocks of stone in the same manner protect the ice from melting
underneath, and are found standing on pedestals of ice, often several
feet in height. An interesting feature of these blocks is that, when the
pedestal fails, the block uniformly falls towards the sun, since that is
the side on which the melting has proceeded most rapidly.
If the meteorological forces are so balanced that the foot of a glacier
remains at the same place for any great length of time, there must be a
great accumulation of earthy _débris_ at the stationary point, since the
motion of the ice is constantly bearing its lines of lateral and medial
moraine downwards to be deposited, year by year, at the melting line
along the front.
Such accumulations are called _terminal_ moraines, and the process of
their formation may be seen at the foot of almost any large glacier. The
pile of material thus confusedly heaped up in front of some of the larger
glaciers of the world is enormous.
The melting away of the lower part of a glacier gives rise also to
several other characteristic phenomena. Where the foot of a glacier
chances to be on comparatively level land, the terminal moraine often
covers a great extent of ice, and protects it from melting for an
indefinite period of time. When the ice finally melts away and removes
the support from the overlying morainic _débris_, this settles down in
a very irregular manner, leaving enclosed depressions to which there
is no natural outlet. These depressions, from their resemblance to a
familiar domestic utensil, are technically known as _kettle-holes_. The
terminal moraines of ancient glaciers may often be traced by the relative
abundance of these kettle-holes.
The streams of water arising both from the rainfall and from the melting
of the ice also produce a peculiar effect about the foot of an extensive
glacier. Sometimes these streams cut long, open channels near the end
of the glacier, and sweep into it vast quantities of morainic material,
which is pushed along by the torrential current, and, after being
abraded, rolled, and sorted, is deposited in a delta about its mouth, or
left stranded in long lines between the ice-walls which have determined
its course. At other times the stream has disappeared far back in the
glacier, and plunged into a crevasse (technically called a _moulin_),
whence it flows onwards as a subglacial stream. But in this case the
deposits might closely resemble those of the previous description. In
both cases, when the ice has finally melted away, peculiar ridge-like
deposits of sorted material remain, to mark the temporary line of
drainage. These exist abundantly in most regions which have been covered
with glacial ice, and are referred to in Scotland as _kames_, in Ireland
as _eskers_, and in Sweden as _osars_. In this volume we shall call them
_kames_, and the deltas spread out in front of them will be referred to
as _kame-plains_.
With this preliminary description of glacial phenomena, we will proceed
to give, first, a brief enumeration and description of the ice-fields
which are still existing in the world; second, the evidences of the
former existence of far more extensive ice-fields; and, third, the
relation of the Glacial period to some of the vicissitudes which have
attended the life of man in the world.
The geological period of which we shall treat is variously designated by
different writers. By some it is simply called the "post-Tertiary," or
"Quaternary"; by others the term "post-Pliocene" is used, to indicate
more sharply its distinction from the latter portion of the Tertiary
period; by others this nicety of distinction is expressed by the term
"Pleistocene." But, since the whole epoch was peculiarly characterised
by the presence of glaciers, which have not even yet wholly disappeared,
we may properly refer to it altogether under the descriptive name of
"Glacial" period.