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THE

AMERICAN GEOLOGIST

A MONTHLY JOURNAL OF GEOLOGY
AND

ALLIED SCIENCES

Editor: N. H. WINCHELL, Minneapolis, Minn.

ASSOCIATE EDITORS.

FLORENCE Bascom, Bryn Mawr, Pa.

CHARLES E. BEECHER, New Haven, Conn.

SAMUEL CALVIN, lowa City, Towa.
JOHN M. CLARKE, Albany, N. Y. PERSIFOR FRAZER, Philadelphia, Pa.
Epwarp W. CLAaypoLn, Akron, Ohio. ULyssEs S. GRANT, Minneapolis, Minn.
JoHN EYERMAN, Hastoa, Pa. WARREN UPHAM, St. Paul, Minn.

MARSHMAN E. WADSwWoRTH, Houghton, Mich.

4 IsRAEL C, WHITE, Morgantown, W. Va.

VOLUME XXII

JuLY To DECEMBER, 1898

MINNEAPOLIS, MINN.
THE GEOLOGICAL PUBLISHING COMPANY

1898

THE FRANKLIN PRINTING Co., Printers

Digitized by the Internet Archive
in 2010 with funding from
University of Illinois Urbana-Champaign

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Vi2Z
CONTENTS
JULY NUMBER.
PAGE
Wave-Formed Cuspate Forelands. R. S. Tarr.
[Plates I-IV. |....... oo tan A We 2g 1 SR ee SO ney!
Osage vs. Augusta. Sruarr We.rer, University of
LST Gi SASS ee I oe cee ale AE SRB 1 aan ee 12
On the Development of Tetradium Cellulosum Hall sp.
inmeRononMAnn, Put), i late Vo | ist. . 16
The Geology of the Environs of Albuquerque, New
Riemieom Osu Hmrgicn,» | Plate: VE. |... 22 30

The Mecklenburg or Baltic Moraines. Warren UpHamM. 34

Review of Recent Geological Literature.—Geology of the Yukon Gold
District, Alaska. J. Epwarp Spurr, 49.—Studies on Cambrian
Faunas. G. F. Marrurew, 50.—Paleontologische und _ strati-
graphische Notizen aus Anatolien. Von J. F. Pomprcxs, 51.—
History of Mining and Quarrying in Minnesota. Warren UpHam,
51.—The Valley Regions of Alabama (Paleozoic Strata). Hrnry
McCattey, 52.—Summary Report of ‘the Geological Survey De-
partment (Canada) for the year 1897, 52.—Das Paleozoicum
Polnischen Mittelgebirge. Dr. GEorGE Guricn, 53.

Monthly Authors’ Catalogue of American Geological Literature, 53.

Correspondence.—Recent Seismic Disturbances in Nicaragua. J.
CRAWFORD, 56.—The St. Croix River Valley. A.H. Etrrman, 58.

Personal and Scientific News, 61.
AUGUST NUMBER
Remains of a Species of Bos in the Quaternary of Ari-
Fafa ae PNA Le 0A eae Rn a re 65
The Significance of the Fragmental Eruptive Debris at
Taylons wails, Minn.” NaH. WINCHELL.... 0000.0. (oe

The Hypothesis of a Cincinnati Silurian Island.

dees vel igre) 1B YN BV 6 fc gaa see Sere A ee an 78
Weathering of Diabase near Chatham, Virginia.

SURER OME A oaler a, WP AUS UON oi 20 Fe bapa rete cn agageen retest -icreecetas sce oo 85
Fjords and Submerged ak of Europe. Warren

(72 0A oe neo a eee eee ee Ee Pec 101

Ge)! 6- }

IV Contents.

Observations on the Classification of the Mississippian

Series, .C. Ri Keres. 250...0405:55 ee
Editorial Comment.—The Question of the Differentiation of Magmas,
113:

Review of Recent Geological Literatnre.—The Physical Geography of
New Jersey. R. D. Satispury and C. C. VeERMEULE, 123.—North-
ward over The Great Ice. R. E. Peary, 123.—Note sur les Gise-
ments d’or du Mexique. EzrQurmzn OrpDoNEz, 124.

Monthly Authors’ Catalogue of American Geological Literature, 124.

Personal and Scientific News, 129.

SEPTEMBER NUMBER. .

The Geology of the Keweenawan Area in Northeastern
Minnesota, III. [Plate VII] A.H. Errrmaw........ Ns
Raised Shorelines at Trondhjem. Warren UPHAM... 149
Glacial Geology in America. H. L. Farrcuinp ................. 154

Editorial Comment.—The West Coast of Greenland, 189.

Review of Recent Geological Literature.—Geological Survey of Georgia,
Preliminary Report on a part of the Phosphates and Marls of
Georgia. §S. W. McCa ttre, 193.—On the Interglacial Submerg-
ence of Great Britain. Henr. Munrue, 193.—Geological Survey
of Georgia, Preliminary Report on a part of the Waterpowers of
Georgia. B. M. Hatt, 196.

Monthly Authors’ Catalogue of American Geological Literature, 197.

OCTOBER NUMBER.

Glacial Phenomena in Okanogan County, Washington.
Wat. lL. Dawsone = pnts ad mete Re See hens k 2038
Microseopieal Light in Geological Darkness. E. W.
GLAYPOLE (2... (25. Ue eae remo ee. SS Na cS ee er

Note on the Characters of Mesolite from Minnesota.

IN. EL. WINCH EEA: 25 opener ar ene eee eae 228
Glacial Rivers and Lakes in Sweden. WaArreEN UPHAM. 230
Review of Recent Geological Literature.—Ueber die Verbreitung der

Euloma-Niobe-Fauna (der Ceratopygi kalk fauna) in Europa.

Pror. Dr. W. C. Broaacsr, 236.—Occurrence of Fossil Fishes in

the Devonian of Iowa. Cuas. R. Eastman, 237.—Geological Sur-

vey of New Jersey. Annual Report of the State Geologist, Pror.

J.C. Smock, 239.—Iowa Geological Survey Vol. VIII; Annual

Report 1897, with Accompanying Papers. SAMUEL CaLvIN and
H. F.. Barn, 240.

Contents. Vv

Monthly Authors’ Catalogue of American Geological Literature, 240.

Correspondence.—On the Occurrence of Cubanite at Butte, Montana.
H. V. WincuE LL, 245.—Drift Formations of Long Island. Joun
Bryson, 245.—Bison Latifrons and Bos Arizonica, Wm. P. Biaxe,
248.—Geology and Geography at the American Association Meet-
ing. WaRREN UpuHam, 248.

Personal and Scientific News, 266.

NOVEMBER NUMBER.
Geological Phenomena resulting from the Surface Ten-

sion of Water. [Plate VIII.] Groree E. Lapp... 267
The Occurrence of Copper and Lead in the San Andreas

and Caballo Mountains. [Illustrated.] CC. L.

LSLTMTRIBINGTC Made, oe are Seek na te Se a a ee 285
Giants’ Kettles near Christiania and in Lucerne. War-

Sia) D) FETED. Gap poeta i Pea Sa eee iy an ee EEN aN 291

Origin of the Archean Igneous Rocks. N. H. Wincuetyi. 299

Glacial Theories—Cosmical and Terrestrial. E. W.
Teg SLEMDTBT OG 8 ot x A me RIED NIRS dA Cae eR 7 310

Intraformational Conglomerates in the Galena Series.
er een fo PW ARDEBON! 2s tore eu roe 315

Editorial Comment.—Drygalski’s Glacial Studies in Greenland, 323.

Review of Recent Geological Literature —-[New York] Fifteenth An-
nual Report of the State Geologist, [Prof. James Hall] for the year
1895, vol. I, 324.--Interglacial deposits in Iowa; a Symposium pre-
sented at the lowa Academy of Sciences, Dec. 28, 1897, by Carvin,
LEVERETT, Batn, UppEN, 326.—Report on a Traverse of the North-
ern part of the Labrador Peninsula, from Richmond gulf to Un-
gava bay, A. P. Low, 326.—Text Book of Mineralogy, with an ex-
tended treatise on Physical Mineralogy. Epwarp Satispury
Dana, 328.—Manual of Determinative Mineralogy, with an intro-
duction on Blowpipe analysis, Gro. J. BRusH; revised and en-
larged with new tables, by Samugt L. PENFIELD, 328.

Monthly Authors’ Catalogue of Geological Literature, 328.
Correspondence.—Glacial Observations in the Champlain-St. Lawrence
Valley. G. FREDERICK WriGHT, 333.
DECEMBER NUMBER.
On the Dikes in the vicinity of Portland, Maine. E. C.
[Deel Dap Soy SA led Fic e. Gl eee ve eae ind eee 335
Thomsonite and Lintonite from the North Shore of Lake
Superior. N. H. WincHELL

VI Contents.

Primitive Man in the Somme Valley. Warren UrpnHam. 350

The great Terrace of the Columbia and other topo-
graphie Features in the Neighborhood of Lake
Chelan, Washington. IsrRAEL C. RUSSELL... ........... 362

The Occurrence of Cretaceous Fossils in the Eocene of
Maryland. Rurus Marner Baae, JR.................. 379

Review of Recent Geological Literature.—Maryland Geological
Survey. Wa. Buttock CxLarK, 375.—Orthclose as Gangue
Mineral in a fissure Vein. WALDEMAR LinDGREN, 377.—
Notes on Rocks and Minerals from California. H. W.
Turner, 377.—Mineralogical Notes on Anthophyllite, En-
statite and Beryl (Emerald) from North Carolina. J. H.
Prart, 377.—The Jerome (Kansas) Meteorite. Henry 8S.
WASHINGTON, 377.—On the Origin of the Corundum associa-
ted with the Peridotytes in North Carolina. J. H. Prarv,
377.--Erionite, a new Zeolite. ARTHUR S. HaKLE, 378.—
Metamorphism of Rocks and Rock Flowage. C. R. Van
Hise, 378.—Mineralogical Notes. C. H. Warren, 379.—
Sdlosbergyte and Tinguayte from Essex county, Mass.
Henry S. Wasurneton, 380.— Distribution and Quantita-
tive Occurrence of Vanadium and Molybdenum in Rocks of
the United States. W. F. Hiniesranp, 380.—An Occur-
rence of Dunyte in Western Massachusetts. G.C. Marrin,
380.—Chemical and Mineral Relationships in Igneous
Rocks. Josepx P. Ippryas, 381.—A Study of some Exam-
ples of Rock Variation. J. Morean CLEMEnts, 381.—Notes
on some Igneous, Metamorphic and Sedimentary Rocks of
the Coast Ranges of California. H. W. Turner, 381.—
Syenite-porphyry Dikes in the Northern Adirondacks. H.
P. CusHine, 382.—Clay Deposits and Clay Industry in
North Carolina. HeEtnricH Ries, 382.—Weathering of
Alnoyte in Manheim, New York. C. H. Smyru, 382.—Om
ACEROCAREZONEN ett bidrag till Kannedomen om Skanes
Olénidenskiffrar. Jon. Cor. Mopera och HsEtmMar MOt-
LER, 383.—UEBER CALYMMENE, Brongniart. J. F. Pom-
PECKJ, 384.—The Special Report on Kansas Coal. ERas-
Mus HawortH: W. R. Crane, 384.—Contribution 4 |’ étude
micrographique des terrains sédimentaires. LucrEN CaYEux,
388.

Monthly Author’s Catalogue of American Geological Literature, 391.

Personal and Scientific News, 394.

L'BRARY
OF THE
UNIVERSITY of ILLINOIS.

Tur AMERICAN GEOLOGIST, VOL. UWE PLATE I.

— pee,

Ne ae

Fre. 1. To illustrate position of Crowbar point.

Cape Breton island. View taken

North arm of cuspate foreland at Sydney,

FiG. 2.
from near base.

“TtRRARY
OF THE
UNIVERSITY of ILLINOIS,

Tue AMERICAN GEOLOGIST, Vou, XXII. PLATE II.

preae uw é ' y v5 = . ~~

Fre, 1. View of base of cuspate foreland, Sydney, Cape Breton island. View taken
from same point as figure 2, of plate I. Source of the
materials shown in the sea cliff.

Fig. 2. Barrachois hook, Bras d’Or, Cape Breton island. Right hand, north; left
hand, south or side open to strong waves.

LIBRARY
OF THE
UNIVERSITY of (LLINGIS:

THE AMERICAN GEOLOGIST, Vou. XXIT. PLATE III.

Fria. 1. Island tied to mainland by two bars, Bras d’ Or, Cape Breton island. Cause
somewhat resembling that of the cusps.

Fic. 2. Very perfect cuspate foreland, Bras d’Or, Cape Breton island, projecting
from a point.

Fic. 3. Barconnecting islands and bar from islands growing toward a bar
developing from the mainland on the least protected side.

pIBRARY

oF THE
\NIVERSITY of ILLINOIS:

Tor AMERICAN GEOLOGIST, Vou. XXII. PLATE LV.

Fie. 1. Extreme tip of Barrachois hook, Bras d’Or, Cape Breton island, showing
coarseness of material composing it.

I arr ton

Fig. 2. A spit, hooked at the end and growing toward the shore to form

the other arm of a cusp.

THE

AMERICAN GEOLOGIST.

Vor. XXII. JULY, F898; No. 1

WAVE-FORMED CUSPATE FORELANDS.*
: ? By R. S. TARR, Ithaca, N. Y.

Nature of the Study.

In an important paper discussing the origin of cuspate
forelands, Mr. F. S. Gullivert divides these land forms into
three main classes, according to origin,—current (meaning the
oceanic circulation), tidal and delta. Wind waves and wind-
formed shore currents are not considered among the effective
causes. While it is distinctly my opinion that the wind is
nearly everywhere the chief and most common cause for the
formation of such shore features, | can do no more here than
to state this opinion. Nevertheless, whether this personal
conclusion is too broad or not, wave action must be admitted
as a fourth cause, and I believe that investigation in the field
will show that it is the most efficient of the four. The chief
object of this article is to show that at least some cuspate
forelands are wave-built.

I have studied the formation of projecting forelands in two
places, one on the shores of lake Cayuga, the other in the
partly enclosed waters of Cape Breton island, north of the
Nova Scotia peninsula. In the latter place hooks, bars and

*The work at Cape Breton was done in the early summer of 1896, and
the publication was delaved in the hope that I should be able to make a
more detailed study in 1897; but this proved impossible, and as I may
never visit the region again [have thought it well to call attention to
these deposits.

Bull. Geol. Soc. Am., vol. VII, 1895-6, pp. 399-422.

2 The American Geologist. July, 1898

cuspate forelands are developed in a wonderful degree of per-
fection. In lake Cayuga there are three prominent forms of
projecting forelands, the delta, the modified delta, and the
spit (sometimes partly hooked). The delta represents merely
the dumping of debris brought by a stream into the-lake, ac-
companied by a certain modification by lake waves and cur-
rents. Sometimes the supply so far exceeds the action of
waves and currents to remove it, that the delta form remains
perfect; but at times it is considerably modified by the action
of lake waters.

Spit on Lake Cayuga Shore-—On the shore of lake
Cayuga the modification of delta form has been mainly the
result of wave work. This would be inferred from the size
of the pebbles which occur on the delta front; and the truth
of the inference is verified by a very slight study of the shore.
In any body of water, but particularly in a narrow body with
rather high valley walls, the direction of the wave attack is
in nearly all cases diagonal to the coast. Only rarely can
the waves advance directly upon the shore in a direction nor-
mal to it. In a narrow valley of some depth, the waves that
do reach the shore at right angles to the trend of the coast are
slight in effect, for they have only the breadth of the valley
in which to form. It is the waves that advance most nearly
parallel to the coast that are the largest, and hence the most
effective. .

Therefore in a narrow and deep lake valley, like that of
lake Cayuga, the most effective, as well as the most violent
waves, come either diagonally or parallel to the coast. (Pl. I,
Fig. 1). These may pass from a northerly or from a southerly
direction; but in this lake the winds from the north are on
the average more violent and more permanent than those
from the south. Hence the conditions are these: in the great
majority of cases the waves extend more or less parallel to
the coast, and those from the south are less powerful and
permanent than those from the north. This produces a de-
cided effect on the topography of the lake coast line. In the
case of the deltas there is usually more modification on the
north than on the south side. Sometimes this consists of the
addition to the delta of wave-derived debris, wrested from
the cliffs, and in other cases the driving of stream material

Wave-formed Cuspate Forelands.—Tarr. 3

to the south. Very slight local conditions will determine
which of these results will be accomplished, and as these vary
the delta form likewise changes.

The effects of these two sets of waves sometimes builds
spits, which reach directly out into the water, possibly curving
at the end; and when they do so, curving toward the south.
Sometimes these spits are supplied with debris mainly by
streams; but in others, and in one very notable case, Crowbar
point (Pl. I, Fig. 1), a few miles north of Ithaca, the spit is
supplied entirely by the waves. It is made of shale pebbles,
and projects directly out into the lake from an exposed point
where the direction of the shore turns somewhat.

This is distinctly an instance of the efficiency of wave
work, both in supplying the materials and in building them
into projecting forelands. Pebbles are brought from the south
and from the north, and at this particular point the battle
of the waves has driven them out into the lake. The predomi-
nance of the north winds has turned the end of the spit some-
what toward the south. Here then is a case, not indeed of a
true cuspate foreland, but of a closely allied form, that is wave
built. There is no stream supply, there is of course no notable
tidal action in the lake, and the action of currents is not com-
petent to move the coarse material. Shore currents of wind-
drift origin, often lasting long after the exciting cause has
disappeared, are well known in lake Cayuga, and they are
doing work; but even during the most violent winds, one will
never find currents of sufficient power to transport pebbles
weighing from an eighth to a quarter of a pound.

There is but one cause left, and this is the waves them-
selves. These are abundantly able to perform the work, and
to me would occur first of all as a most probable cause. One
has but to watch the waves work to see how natural is this
action. Passing nearly parallel to the coast, or, as for that
matter, diagonally to it, the wave breaks and moves forward
as a surf of considerable force. By this forward movement
the pebbles are picked up and pushed along the shore. Again
and again this is done, as wave succeeds wave, and gradually
the pebbles migrate toward a place where they must come to
rest, either in the deep water, or else in the lee of a point. To
this place both the north- and south-moving waves may be

4 The American Geologist. July, 1898

bringing materials, and hence a point grows outward. The
shore currents are operating in the same direction and hence
are cooperating; but they are doing much less than the waves,
and are moving only clay and sand, which of course, are made
to enter into the structure of the spit.

One may well ask why the spit began, and when it will end.
I am not certain that I fully and clearly understand this point,
though I see plainly that it is through no chance or accidental
conditions that the spit develops. It has an explanation in
the law, everywhere illustrated on coast lines, that waves sup-
plied with material will discover the easiest means of dis-
posing of it. In the case of Crowbar point the waves were,
in the first place, driving materials both ways, the south winds
pushing the pebbles toward the north and the north winds
driving them in the reverse direction. There was a bend in
the coast due to the projection of the old land; to this the
waves from the south brought materials, but there they lost
some of their power, and hehce could not continue to carry
all their load beyond the point, so some was dropped on the
very point. The same was true of the waves from the north.
They were able not merely to drive along the materials which
they had wrested from the rocks, but also to turn back some
of the debris which the south waves had driven beyond the
point. But when these waves passed the point ¢ey lost their
force likewise, and so both north- and south-moving waves
made this a dumping ground. As they built the spit out into
the water, the interference of the point with the movement
of materials to the north or south became greater and greater,
until, at present, the spit forms an almost perfect barrier for
the larger fragments. Had the south waves been greatly less
powerful than those from the north, there would have been
built a bar extending nearly parallel to the coast; but with
nearly perfectly balanced waves from the two directions, the
spit must grow directly outward.

The other question is whether the spit will continue to
grow outward indefinitely. Granting the continuation of the
present conditions, the spit must finally destroy the cause for
its further extension, and, I believe, as the next stage, become
a hook, bending toward the south.

As it grows out into the lake, enough material is still driven

Wave-formed Cuspate Forelands—Tarr. 5

up to its base, and part way out on the spit, to influence the
wave, which then reaches it in a direction normal to its length.
So by growing outward, the direction of the shore is actually
changed, and hence the mode of wave action. Passing diag-
onally to the old land, the wave now strikes the foreland at
right angles. Of course an equilibrium will be maintained;
the change in direction of the shore will not be so great that
the wave-brought materials cannot be disposed of, though if
it were the pebbles would be deposited at the base of the spit,
and thus lessen the angle between the oldland and the new.
However, as the spit grows outward, the mecesszty of trans-
portation of wave-derived fragments decreases. On the new
land the waves beat directly, and as they wash directly on and
off the beach they grind the pebbles to and fro, keeping them
in nearly the same place. Both sides of the spit then become
mills in which the pebbles are ground. Before long they are
so worn down that the undertow and shore currents can carry
the ground-up fragments, though their eset is speedily taken
by others. pear yh

Hence, as the spit grows canard ‘the Pebbles that are
supplied have to run the gauntlet of" wave attdék “froth waves
washing directly on the shore; and the /onger the spit grows,
the less chance is there of pebbles being carried very far to-
ward the end. In the first stages of the spit development many
pebbles would be carried to the end, and deposited, rapidly
lengthening the new land. Then the number would rapidly
decrease as the length of the spit increased, and finally the
number that reached the end would slowly decrease, when
the spit would lengthen with extreme slowness. In this stage,
of all the fragments driven to the base of the spit, only a small
portion would escape comminution and widespread scattering.
This part, carried on to the end would finally be so slight
in amount that the spit would actually cease to increase in
length; for the supply at the end would not exceed the abil-
ity of the waves and the currents to carry it away, and dispose
of it in some other place.

In this stage the spit might be changed to a hook, bend-
ing toward the south; for the waves and currents from the
north would be able to drive the materials around the end,
after the ability of the south waves to do so had ceased. In

6 The American Geologist. July, 1898

any particular case the point at which the spit should become
a hook would depend upon the relative strength of the spit-
forming forces; but the hook «aozsld be a permanent form
just so long as the conditions remained uniform. That is,
once begun, during a certain stage of development of a spit,
and in a certain part of a lake, a hook would a/ways remain
in this position unless the spit-forming conditions varied.
This would involve a change in either the relative strength of
the waves, the a@vrection of wave supply, the amount of ma-
‘erial furnished, or the /osztion of the base of supply. Varia-
tions in these directions can come only by a change in the
neighboring land, either in relative level of land and water,
or as the result of erosion. Either of these causes may change
the natural base of the spit, or cause the waves to commence
work on a different kind of rock, or change either the direction
or relative force of the waves.

Spits should therefore vary greatly in length, width, posi-
tion and details of form, according to the various sets of con-
troling forces and conditions. They may vary in width, even
up to the form of cuspate forelands. There seems to be every
eradation between spits and these compound bodies, as there
certainly is sometimes a close relation in cause. From place
to place hooks should also vary greatly in direction, in form,
in length, and in the nature of the spit pedestal. In reality
they do. Probably a close study of these would show a definite
relation between form and surrounding Conditions.

Cuspate Foreland in Sydney Harbor, C. £.—In the harbor
of Sydney, Cape Breton island, there is one of the best in-
stances of a cuspate foreland that I have ever seen (PI. I, Fig.
2). It is probably less than a mile and a half across its base
and considerably more than a mile long, and its northern
and longer side faces the more open water. On the south
side there is an opening near the base, through which the
tide enters and passes into the lagoon inclosed between the
sides of the foreland. The bottom of this lagoon is a mud
flat, during low tide exposed to the air in the greater part
of its area, but transformed to a bay at high water. Upon.
the point formed by the union of these two arms there is a
light house, and beyond this, off the point, is shoal water for
some distance, though on either side the harbor is deep and
navigable by even large ships.

Wave-formed Cuspate Forelands.—Tarr. 7

There is no stream supply for this foreland, but the source
of the material is the cliffs of Carboniferous sandstone and
shale at the base of the bar (Pl. II, Fig. 1). On the northern
or seaward side these rise as wave-cut cliffs, and from their
base there extends outward, toward the end of the bar, a
beach of large, wave-wrested fragments. These become small-
er in size and more rounded as the end of the bar is ap-
proached; but even at the light house, which stands on the
very end, the beach is in large measure made of pebbles.
This part of the harbor is exposed to heavy waves from the
north, and, aside from the cuspate foreland itself, there is
other evidence of their action. The cliffs are distinctly wave-
cut, the beaches contain large rock fragments, and the beach-
face of the bar is high, showing evidence that the waves at
times attain great force and power. On the southern side
there is much less activity, and here the bar is less perfectly
developed.

It is said that this cuspate foreland is wave built. There is
direct evidence of this in the hight of the bar, the nature of
the materials and their evident source. The same conclu-
sion can be reached by the process of elimination. The fore-
land is not stream supplied, for there are no streams at its
base. It is not the result of currents, for these could not
move the larger materials; and, moreover, the people familiar
with the harbor say that there are no rapid currents. The
foreland is not the result of tidal action for the same reason;
the rise and fall of the tide is slight and there are no very
marked tidal currents. The ferries running from Sydney to
North Sydney pass close to the point several times a day,
and the captains of these boats assured me that there were
no very noticeable currents, excepting the gentle inflow and
outflow of the tide.

In this case, as in Crowbar point on lake Cayuga, the
waves have driven materials along shore until a slight change
in the direction of the coast has been reached, and then have
driven this material out into the bay. The less powerful
southern waves have done the same; but here a single spit
has not resulted, mainly because of the greater force of the
north waves, which have caused the end to be deflected to
the south, but partly because the change in direction of the

8 The American Geologist. July, 1898

shore is rather gradual, so that the place of beginning of the
two arms which form the cusp was different. No doubt the
winds from the opposite side of the harbor have helped to
build the bar on the inner or southern side by driving toward
the shore some of the materials from the end of the bar which
is being built outward by the waves from the northern and
more open water. In this connection it is suggestive that
the southern arm is mainly sand, while the northern is mainly
pebbles.*

Here, as in the case of Crowbar point, the result of the
wave action has been to absolutely change the direction of
the coast, so that the larger waves in this place now reach
it in a direction nearly normal, rather than parallel to their
crest lines. They drive materials along shore to the base of
the bar, and then up and down it, where they are ground
fine enough to be in large part removed, either in the under-
tow, or in the currents, or along the bar to its end, where
they are in part deposited to lengthen the foreland, and in
part drifted around the point to help build the bar of the south-
ern side.

Although it is difficult to understand these processes in the
present state of our knowledge of shore lines, it seems evident
that there is an attempt to establish an equilibrium between
wave force, wave direction and sediment supply, and that these
shore forms are an expression of this attempt, which here has
reached a more or less complete degree of success in the es-
tablishment of the equilibrium. No doubt tides and currents
modify this somewhat, but in this case they are distinctly sub-
ordinate. I am certain that a careful study of any particular
foreland, taking into account its form, the nature of the ma-
terial supplied, the depth of the water, the action of the tides
and currents, and particularly of the waves, will in each
case determine the history. We need such studies as these
before we can really understand the details of the processes by
which these interesting shore features are being made.

The Bars of the Bras ad’ Or —In no place have. I ever seen
a more remarkable development of various kinds of bars,

*I believe that the chief cause for the southern arm is that mentioned
later in the paper in a consideration of the cusps of the Bras d’Or
lakes.

Wave-formed Cuspate Forelands.—Tarr. 9

hooks, spits and cuspate forelands than in the Bras d’Or lakes
of Cape Breton island. These so-called lakes are really
drowned valleys, occupied by the sea, and nearly land-locked,
with a wonderfully intricate shore line and a complex maze
of islands, peninsulas and interlocking bays. In some places
the bays are several miles broad, in others mere fjords, a few
hundred yards across, in which there is no opportunity for
the development of currents. The tide rises but two or three
feet, and the testimony of the people who live on the shore
is that there is no noticeable development of currents. The
sole important cause for the movement of materials along
the shore is the wind, which produces small, though very no-
ticeable waves, and of course also some slight shore currents.

There are wonderfully perfect bars across bays, islands
joined to the mainland by bars (PI. III, Fig. 1), cus-
pate forelands of perfect form (PI. III, Fig. 2) and hooks (PI.
ieee 2, and Pl, IV, Fig.°1) of various shapes. I
had but a day in which to examine a few of these, and hence
got very little where I believe it is possible to learn a great
deal about shore lines. Waves were everywhere seen to. be
the cause of the shore features, not merely because other agents
were absent, but also by the direct evidence of the material
composing the bars. In most parts of the narrow Bras d’Or
there is a migration of material along the shore. Here and
there this has necessitated the formation of a bar across a bay,
thus altering the coast somewhat; and now and then an island
has been tied to the coast by bars on its landward side (PI. III,
Fig. 1). In still other cases the coast has been built outward
and made more irregular.

I am not certain that some initial cause is always necessary
for the accumulation of a V-shaped bar of wave origin, though
wherever I have seen them there is always a change in the
oldland coast line (PI. III, Fig. 2). It looks as if there was
first of all an accumulation of material that had been driven
along the shore to some place where further progress was re-
tarded; and that, after a beginning had been made, the process
was accelerated by the increased obstacle, as in the case of
the lake spit. This process continues until a bar is con-
structed, upon which the materials supplied may be ground
down and removed. When this is done, and the materials at

10 The American Geologist. July, 1898

the end are either in the form of small pebbles or sand, the bar
may be sharply turned in the direction away from that of the
prevailing wind.

This turning point is apparently reached and caused when-
ever the force of the waves which reach the end of the bar,
from the direction in which the wave movement is most pow-
erful, is able to remove the materials which the waves from
other directions are driving to the end. That is to say, there
comes a balance of supply and ability to remove, when the
further out-building of the bar must cease. Then there is an
abrupt bend.

This is very well illustrated in the Barrachois hook (PI. II,
Fig. 2, and Pl. IV, Fig. 1), on the eastern side of the Bras
d'Or, about midway between North Sydney and Grand Nar-
rows. It is plainly visible from the train and is a remarkable
feature, being set in the dark waters of a deep and narrow
arm of the sea extending between two high hills. It reaches
directly out from the shore, turned at an angle of about 110°
with the coast, which is the normal angle of the bars forming
the arms of the cuspate forelands in this region. At a distance
of about one hundred or one hundred and twenty-five yards
from the shore it bends abruptly at an angle of 60° or 70°
(Pl. II, Fig. 2) and extends nearly parallel to the coast, until
near its end, at a distance of two hundred or two hundred and
fifty yards from the first elbow, it turns again toward the
shore and then back in the opposite direction, forming a very
perfect hook.

This hook is built out into water which is sixty feet deep,
and hence it represents a distinct bank, which has been piled
along this line as the result of remarkably permanent con-
ditions. It is due to no mere chance, but to the operation of
some very distinct forces, operating for definite causes, in per-
fectly definite ways for a considerable time. In this case the
cause for the bend seems evident. It is a place where the
along-shore waves from the south (left) can transport the di-
minished supply of materials which reach the end of the bar,
and do this so speedily that the bar can reach no further out-
ward, but must turn. This change comes with such force
and persistence that it is posible to build the turned end for
more than two hundred yards in a depth of sixty feet of

Wave-formed Cuspate Forelands —Tarr. II

water.* At the end of this there is a hook, no doubt because
the weaker winds from the north (right), which have only a
very narrow and protected valley in which to blow, are able
to turn the supply backward toward the south, under the pro-
tection of the bar that has grown northward. In other words,
the supply driven along this bent end is not sufficient to build
the bar further north in opposition to the tendency of the very
weak opposing waves to drive the materials backward.

_ In the Bras d’Or there seems to be evidence that under
certain conditions a hook will change to a cuspate foreland.
This has been partly stated above in the explanation of the
Barrachois hook. There, in an enclosed arm of the sea, a
bar that is growing outward is bent, not directly back ¢-
ward the coast, but up the channel before the stronger waves.
In the more open waters of the Bras d’Or, heavy waves often
come directly upon the shore, or else reach it at a high angle.
Such action will naturally tend to interfere with the owtward
growth of a bar which is being constructed by the drift of
materials before the waves that reach the shore diagonally;
and when, finally, the outward growth of this bar becomes
slow, because of diminished supply, the on-shore wind waves
at first produce a hook at the end, and then commence to
build a bar toward the shore (PI. IV, Fig. 2). There are sev-
eral cases of this nature in which a bar, proceeding outward
for some distance, turns landward and produces a partial
hook, which is apparently an incomplete V-shaped cuspate
foreland. In other cases a small bar is starting out from the
land to meet the recurved end of that arm which has developed
most notably (Pl. III, Fig. 3). Then we have a nearly com-
plete cuspate foreland, which would be complete if the end
of the recurved bar, and that of the small one extending out
from the shore, were finally united. Such, I believe, is the
origin of many, and perhaps all, of the cuspate forelands of the
Bras d’Or; and there seems to be nearly every gradation be-
tween the single bar, the bar hooked at the end, and the
double V-shaped cuspate foreland.+ The nearly soldered

*The water is shallower on the inner side of the hook, but even here
is deep.

fIt happens that the two illustrations of these gradations here repro-
duced are from bars ofa very similar nature, whose basal ends are on
islands which the bars are engaged in tying to the mainland. Here cus-
pate forelands are built, though they are made to include off-shore
islands.

12 ‘The American Geologist. July, 1898

southern arm of the Sydney harbor cusp described above
appears to be an instance of an almost closed foreland of this
origin.

It would be unwise to extend the results of this study so
far as to make the generalization that all.cuspate forelands are
derived by means similar to this; but before assuming that
they are not so formed it seems that we should have distinct
evidence that they are not. Is there any place where the
peculiar eddying of tidal currents is known to be at work
building these shore features? Have we any distinct evidence
of the existence of back-set eddies from the Gulf stream,
whose power 1s sufficient to move and guide the distribution
of materials? Such eddies, to cause the prominent cusps of
the Florida coast should, it seems, be very noticeable. It is
possible that this evidence has been brought forward; but if
so I have never seen it.

As small spits and cusps may be made by waves in small,
enclosed and nearly land-locked bodies of water, where proper
conditions exist, so it seems possible that larger cusps, even
those as large as Hatteras, may be made where the supply of
material is more rapid and of finer texture, while the waves
are greater and the shore currents of wind origin more power-
fuland therefore able to move the fine materials. This certainly
seems a possible explanation; and, even though it be not the
correct one, it should at least be discussed as an hypothesis,
and the evidence against it definitely brought forward, if there
is such opposing evidence.

OSAGE VS. AUGUSTA.

By Stuart WELLER, University of Chicago.

In a recent article in this magazine* entitled, “Use of the
Term Augusta in Geology,” C. R. Keyes defends the use of
the term Augusta (Keyes) and its displacement of the older term
Osage (Williams) as the name of one of the major subdivisions
of the Mississippian series.

The science of paleontologic geology is a historical science.
It is something far more than the mere classification of rock

* Am. Geol., vol. XXI, p. 229, April, 1808.

Osage vs. Augusta —Weller. 13

strata. In his investigations of the Lower Carboniferous
faunas of the Mississippi valley Prof. H. S. Williams detected
the records of three distinct chapters in the history of the con-
tinental interior, and to the middle one of these chapters he
gave the name of Osage, the rock strata containing the fossil
records of the chapter being designated as the “Osage group.”
It was recognized that the faunas of the Burlington and Keo-
kuk limestones were a unit in themselves to such an extent
that they should not be divided into several distinct groups,
as had generally been done by earlier geologists. There were
life changes in progress during the time of deposition of these
limestones, but they were internal, evolution changes, not de-
pendent upon profound physical changes or upon the immi-
gration of new forms of life. The records of the Osage chap-
ter in our continental history were found to be best expressed
in these faunas of the Burlington and Keokuk limestones.

Mr. Keyes’ contention that the Osage and Augusta are not
synonymous, because Williams failed to include a portion of
the so-called Warsaw group of older authors in his division, is
based upon unessentials and is not tenable. On the same
ground, if some future investigator were to find that a small
portion of the Chouteau limestone would be better placed with
the superjacent strata, it would be perfectly legitimate for him
to ignore both the names Osage and Augusta, and to propose
still a third, and so still further increase the confusion.

As a matter of fact, Williams did recognize that one
portion of the Warsaw faunas were of Osage age and another
of St. Louis age; and he showed, before Mr. Keyes, that the
fauna of the Warsaw group had no separate place in a natural
classification of the Mississippian faunas. He says:* ‘The
faunas of the Chester, St. Louis and most[ not 2//] of those
referred to the Warsaw formations are paleontologically more
closely allied than they are to the faunas of the Keokuk and
Burlington.” It is thus seen that he carefully excludes a part
of the Warsaw faunas, and clearly implies their relationship
with the Osage faunas. That Mr. Keyes and Prof. Williams
are in accord in this regard is shown by the following state-
ment by Mr. Keyes:+ “In a majority of cases the so-called

*U. S. Geol. Surv., Bull. 80, p. 1609, 1801.
tGeol Surv. Iowa, vol. I., p. 70, 1893.

14 The American Geologist. July, 1398

Warsaw is clearly the lower part of the St. Louis limestone.”
Prof. Williams’ classification of the strata of the Mississip-
pian series is expressed in tabular form as follows:*

\ Chester.
( Genevieve group. {4 St. Louis.
/ Warsaw. (in part).

{ Keokuk.

Mississippian Osage group. :
: / Burlington.

Series.

Chouteau limestone and Ver-
micular and Lithographic
| Chouteau group. J/ formations as proposed by
G. C. Broadhead, in the fol-
L lowing report.

In this way the name Osage was established in 1891. Ina
papery bearing the date of June, 1892, Mr. Keyes accepted
without question and with no intimation that the name was
used “provisionally,” the name Osage and used it in a classi-
fication of the strata of the Mississippian section, giving it the
following definition:

OSAGE LIMESTONES.

Definition and general Relations.—From a purely paleontological
standpoint, the advisability of including the Burlington and Keokuk
limestones under a single name was pointed out several years ago.
For this long needed term Williams has proposed the name “Osage.”

At that time nothing was said about the name being pro-
posed under the “misconception” that the Burlington and
Keokuk faunas were mingled in southwestern Missouri,—a
“misconception,” which, if it ever did exist, would have no
bearing on the subject. Neither did the supposed fact that ~
Williams had entirely excluded the “Warsaw” from his Osage
group seem to be a serious objection to Mr. Keyes, at this
time, against using the name. The following tabulation of his
classification of these strata is given by Mr. Keyes in this
paper:

*U. S. Geol. Surv., Bull. 80, p. 169, 1801.
+ Bull. Geol. Soc. Am., vol. 3, p. 283.

Osage vs. Augusta—Weller. _ 15

{ Kaskaskia group.

“Kaskaskia Limestone.”

“Chester shales.’
Aux Vases sandstone.

“Ste. Genevieve limestone.”

St. Louis group. St. Louis limestone.
Warsaw limestone (in part,
not typical).

Mississippian
Series. Warsaw shales and _ lime-
stone (typical).
“Geode bed.”

Osage group. Keokuk limestone.

Upper Burlington limestone.
Lower Burlington limestone.

| Kinderhook group. ) Hannibal Shales.

H Chouteau limestone.
Louisiana limestone.

In 1893, at the time of publication of volume one of the
Iowa geological survey, the “misconception” under which the
name Osage was proposed had been discovered by Mr. Keyes,
and the name Augusta was proposed as follows :*

AUGUSTA LIMESTONE.

This term is applied to those rocks exposed in the Mississippi
valley which have hitherto been called the Burlington and Keokuk
limestones.

In this initial definition of Augusta, no mention is made
of the Warsaw, but in the general classification of the strata
the Warsaw was divided between the St. Louis and the Au-
gusta in the same manner in which it was divided between
the St. Louis and Osage in the previous paper. That the
name Augusta was recognized at this time as synonymous
with Osage, is shown by the following sentence :f “In the
meantime Williams suggested for this limestone the title
‘Osage,’ from the name of the chief river of southwestern Mis-
souri, which cuts through some of the Lower Carboniferous
series in Saint Clair county.” Apparently the only reason in
the mind of its author for the proposal of Augusta, was his
belief that it was a better name than Osage.

’*Iowa Geol. Surv., vol. I, p. 50.
PlLOG. cit., pi 50

16 The American Geologist. July, 1898

As to whether Osage or Augusta shall stand as a term in
American geology can only be settled by impartial judges.
Osage clearly has priority and has been adopted by Dana*
and by Scottt in the two latest text books of the science.
The name was also adopted by the late geological survey of
Arkansas. The name Augusta has been used only by the
geological surveys of Iowa and Missouri, with which Mr.
Keyes has been personally associated.

ON THE DEVELOPMENT OF TETRADIUM
CELLULOSUM HALL, SP.
By R. RuEDEMANN, Ph. D., Dolgeville, N. Y.
(Plate V.)

The writer found in the Birdseye limestone (lower Tren-
ton) of Ingharm’s Mills, Herkimer county, N. Y., a layer of
limestone (1%° thick), which consists largely of a fossil de-
scribed by Prof. James Hall} as Phytopsis cellulosum. The oc-
currence of the fossils in the neighborhood of banks with
carbonaceous “birdseyes” (described as Phytopsis tubulosum
in the same paper) and the apparent cellular structure in
transverse and longitudinal sections, on account of the sep-
tal partitions and tabulz, invited the above identification at
a time when the genus Zetradium, though already created
by Dana, was not yet well known; no species of it having
been described.

The material from Ingharm’s Mills is so well preserved
that itat once shows that the fossil belongs to the little
known and interesting genus 7etradium, Dana, of the tabu-
late corals and, therefore, should be identified as Zetradium
‘cellulosum Hall, sp., which name it also bears in the catalogue
of Prof. Hall’s collection. A figure given by Prof. Hall well
illustrates that this species does not grow in compact masses
like most other species of Tetradium, but possesses a cespi-
tose, dichotomously branching corallum. This mode of
crowth, however, gives an excellent opportunity to study the

*Man. Geol., 4th ed., pp. 634 and 637.
+Intro. to Geol., p. 409.
{Nat. Hist. of New York, part VI, Paleontology, vol. I, p. 39, 1847.

PLATE V.

THE AMERICAN GEOLOGIST, Vou. XXII.

. 3

ot

SE yee F
mo

ci.

Tetradium Cellulosum Hall, SP.

QIVRAKY
Or THE
UNIVERSITY of ILLINOIS:

Development of Tetradium Cellulosum Hall—Ruedemann. 17

development of the corallites by successive sections and thus
removes some of the doubts which, judging from the litera-
ture on that genus, still exist.

- A short review of the literature will best show what rela-
tions of the genus are so insufficiently known that they have
been made the special subject of research by the writer.

Dana*, having used a fossil from an unknown locality,
characterized the genus as follows: ‘“Corallum massive, con-
sisting of 4-sided tubes, and cells with thin septa or parietes;
cells stellate with four narrow lamine,”’ which characteriza-
tion enabled Prof. Safford to discover the coral in the Ordo-
vician of middle Tennessee. Prof. Safford, for the first time,
gave a full description of the genus, which he placed among
the tabulates, and described several forms.- The most im-
portant of his observations for our investigation are the fol-
lowing: The tubes are most frequently united throughout
laterally, forming massive coralla. The increase appears to be
by division of the tubes, the latter splitting sometimes into
two cell-tubes, not infrequently perhaps into four; opposite
lJamine united form the new walls of the young cells, each
of which isin the meantime supplied with its four rays.
These rays, however, were regarded by Prof. Safford as not
solely serving the process of fission, but also as being of the
character of septa, as the following quotations show: ‘This
group we regard as being allied in some respects to the fAa-
vositide, while on the other hand, the cruciform arrangement
of the lamellz unite with the Zoantharia rugosa of MM. Milne
Edwards and Haime; in fact, it appears to afford an inter-
esting type of the quadripartite character of the lamella, first
pointed out by these distinguished authors in many paleo
zoic corals.” And in the description of Zetradium fibratum
Saff., it is said ‘The four lamellz, distinct, nearly reaching
the centre of the tubes.”

Prof. G. Rominger,f{ ten years later, shows by a_ remark
of his that he had recognized the fission of the corallites of

*U. S. Exploring Expedition during 1838 to 1842 under command of
Charles Wilkes, vol. VIII, p. 701.
tJ. M. Safford; Remarks on the genus TZetradium, with notices of
the species found in middle Tennessee, Am. Jour. Sci., vol. 22, 1856, p.
236.
{Observations on Ch@tetes and some related genera, Proc. Acad.
Nat. Sci. Philadelphia, 1866, p. 113.

18 The American Geologist. July, 1898

Tetradium into four parts. He writes: “I know of only one
fossil resembling C/etetes, in which the tubes are multiplied
by division, this is the genus 7etradium, whose tubes regular-
ly divide into four parts.’’

Later Nicholson* had repeatedly occasion to study the
fossil and to discuss its affinities.

In his excellent manual the characters of Tetradium are
especially clearly set forth as follows:

“This small family includes only the single genus Tetradium, which
so far, has only been detected in the Ordovician rocks of North America.
In this genus the corallum is massive, and is composed of long prismatic
and closely contiguous corallites, which are of small size and have im-
perforate walls. The tubes are furnished with longitudinal inflections
or plications, generally four in number in each tube, which do not reach
the centre of the visceral chamber, and which give a characteristic cruci-
form or petaloid aspect to cross-sections of the corallites. These longi-
tudinal plications are apparently to be regarded as of the nature of septa
or pseudosepta. Zetradium appears tobe related to H/alysztes, but its
true affinities and zoological position are uncertain.”

The following points in this description are of especial
importance to us: Nicholson expressly states that the plica-
tions do not reach the centre and therefore are not to be
compared to the longitudinal partitions projecting into the
visceral chambers of the corallites of Chq@tetes, which indi-
cate the incompleted fission of the tubes, but that they are
to be regarded as septa or pseudosepta.

Further, Nicholson had observed beforet+ that the coral-
lites are “in close contact, but not amalgamated by their
walls” and that, hence, a double wall is observable.

These observations induced him to consider 7etvadium as
not so closely related to Cheéefes as its habitus would indi-

*(1) H.A. Nicholson and Rob. Etheridge; On the genus 7e¢radium,
Dana, and on a British species of the same, in Ann. and Mag.,, 4th series,
vol. XX, 1877.

(2) H. A. Nicholson and Rob. Etheridge; A monograph of the Silur-
ian fossils of the Girvan district in Ayrshire, fascicle 1, 1878, p. 29.

(3) Nicholson; On the structure and affinities of the tabulate corals
of the Palaeozoic period, London, 1879.

(4) All. Nicholson and Rich. Lyddekker: Manual of Palzontology,
1889, p. 340.

+Compare his papers on the Silurian fossils of the Girvan district
and on the structure and affinities of the tabulate corals, etc.

Development of Tetradium Cellulosum Hall.—Ruedemann. 19

cate, but to place it rather near the Halysttide, a view which
had also been suggested by Safford.*

Nicholson discusses the position of 7etradium among the
Tabulata more fully in his paper on the genus 7Jetradium,
Dana, etc., where he writes:

“Amongst the other groups of corals which have been generally referred
to the miscellaneous division of the “Tabulata,” it is difficult to find one to
which Ze¢radium could be referred with entire propriety. - - - With
the Halysitide the genus has some decided affinities, which are increased
by Prof. Safford’s observation that the corallum sometimes resembles
that of Hadlysites or of Syringopora in form. We have not, however,
noticed this mode of growth in any of the specimens which have been
examined by us, and the corallum in general is quite similar in form to
that of the massive species of Favosttes or Chetetes. Under any circum-
stances, should the genus be ultimately referred to this family, it will be
in the immediate neighborhood of /adysz¢es itself that it must find its
place. - - - The only other group that needs consideration in this con-
nection is that of the Chetetide. In general form and appearance there
is the closest possible resemblance betweenthe present genus and some
of the massive forms of Ch@tetes or Monticulifora; but the peculiar sep-
ta of the former are quite sufficient to distinguish them. --- Upon the
whole, therefore, it is perhaps safest to regard 7etradium as an ally of
flalysites, with some affinities to Chefefes, and thus forming a connect-
ing link between the families of the Walysttid@ and Chetetide.”

Nicholson’s view became the prevailing one, for Miller
and Zittel describe Tetradium as having four septa, which do
not reach the centre of the visceral cavity and Zittel} places
the genus in the appendix, containing “genera from the
group Zoantharia Tabulata, E. H., of entirely doubtful sys-
tematic position.”

In later years, however, Prof. M. Neumayrf advanced a
different view, viz. that Zetradiwm and Chetetes are closely
related, that the composition of the walls of Zetradium of
two lamelle, which constitutes the principal difference be-
tween the two genera, has not yet been conclusively proved,

*Safford (op. cit., p. 236) writes “The tubes are most frequently united
throughout laterally, forming massive coralla resembling more or less
those of Favosttes and Ch@tetes; sometimes, however, they are united
in single intersecting series, as in /alysttes catenulatus, Linn., not infre-
quently too the tubes are isolated, or only united at irregular intervals,
thus forming loose, fasciculated coralla resembling certain forms of
Syringopora.”

+ Handbuch der Palzontologie, Palazontologie, Bd. 1, p. 619.
fDie Stamme des Thierreiches, Wirbellose Thiere, vol. 1, 1889, p. 317.

20 The American Geologist. July, 1898

and that the so-called septa are only incomplete new _parti-
tions, because their number is not always four; their form
agrees with that of the projections of Chetetes; and because
the corallites often exhibit long and irregular transversal sect-
ions, instead of quadratic ones. ‘A sure decision on the re-
lationship between Chevetes and Tetradium,’ writes Neumayr,
‘depends principally upon the demonstration of the character
of the walls; if the latter are simple, the differences are so
small that both genera must be placed into the same family;
if the walls are double, Zetradium can be retained in a_ sepa-
rate family, which, however, must be placed directly besides
the Chetetide.”’

Lately Dr. F. W. Sardeson* has also expressed his be-
lief, that the ‘tpseudosepta” of Yetradium are only fissional
partitions.

The opportunity to study the still doubtful character of
the “septa” and of the walls, as well as the observation of
the mode of formation of the peculiar chain-like arrange-
ment of the corallites, have induced the writer to submit the
present paper. The investigation was made by successively
erinding off the corallaand by making successive sections of
especially interesting stages, The figures are all taken from
sections.

The youngest stage which could be obtained is represen-
ted in figure 1. The diameter of the corallite is .7 mm. _ Its
most remarkable features are:

1) Thevery thick walls which strongly contrast with
the thin walls of later stages.

2) The complete lack of structure in the walls, which
are composed of perfectly transparent calcite crystals, while
the matrix consists of an opaque, fine grained calcareous
matter.

3) The distinct formation of the laminz by a_ plication
of the entire wall.

4) The formation of the first two plications in two adja-
cent quadrants, giving the corallites a symmetrical appear-
ance instead of a regular one. As the irregular course and
smallness of the young corallites makes it extremely diffi-

*Ueber die Beziehungen der fossilen Tabulaten zu den Alcyonarien
Stuttgart, 1896, p. 346.

Development of Tetradium Cellulosum Hall—Ruedemann. 21

cult to trace them in the hard and opaque matrix, the writer
has not succeeded in obtaining other equally young or young-
er stages and, therefore, has failed in establishing the fact of
thesymmetrical form of thisstage beyond doubt. But the sup-
position of the symmetrical character of the young corallites
is supported by later stages, in which again two adjacent
plications appear. (Cf. figs. 8, 9.)

The next two plications grow so fast that they soon at-
tain equal length with the first two and, thus, the character-
istic form with four plications is produced. (Fig. 2.) The
diameter of this stage is I mm.

The four plications gradually extend deeper and deeper
into the visceral chamber, until they unite in the centre, di-
viding the whole into four chambers. Figure 10 represents
a corallite shortly before the completion of the fission into
four young individuals. As this and all other sections de-
monstrate (compare figs. 8, g), two new plications appear
between the primary ones prior to the coalescence of the
latter. There are, therefore, now twelve plications present,
four longer and eight shorter ones, This stage which is
especially frequently observable in the older compound co-
ralla, apparently has given rise to the remark, made in some
papers on Zetradium, that while generally there are four
“septa” present, also a greater or smaller number may be
observed. As mentioned before, the formation of two pli-
cations in adjacent quadrants of these secondary corallites
renders the latter alsosymmetrical. In the majority of coral-
lites there appear prior to the coalescence of the primary pli-
cations but subsequent to the formation of the two secondary
ones ineach chamber two more on the primary ones, thus com-
pleting the set of four plications in each secondary corallite.
(Cf. figs. 6a, 10.) The formation of the secondary projec-
tions by folding is not so distinct as that of the primary
ones; it is, however, indicated by the fact that secondary
plications of adjacent corallites are rarely continuous, but
typically alternating on the primary plications (see figs. 9,
10); it becomes also apparent from the structure of the wall
in the original to fig. 16a.

By the coalescence of the first four plications the very
pretty and characteristic stage, represented in figs. 3 and 4,

22 The American Geologist. July, 1898

results. The section of the corallum is subquadratic; the

four corallites are of equal size, and the walls are still con--
siderably thicker than those of later stages. The young

corallites have a symmetrical section, because the lobes at

the angles of the square are, notwithstanding their being

oldest, smaller that the others, as if the growth had been

checked by the thick common wall of the colony. (See

fmeeGs OA OH)

The four secondary corallites complete their fission in-
dependently of each other. Quite often one corallite will
divide long before the others anda corallum with seven cor-
allites will result (fig, 5). This stage with seven corallites
is as common as the next stages with 10 or 13 corallites (figs. -
6 and 7), where 2 resp. 3 corallites have divided. In the
majority of the cases, however, all four secondary corallites
divide harmoniously. Sections with 16 equally developed
corallites (fig. 8) are therefore hardly ever missed on a chip
of the Zetradiwn-bearing bank. The fission proceeds regu-
larly and coralla with 19 and 22 corallites still show distinct-
ly their derivation and the former arrangement of the
mother corallites, while exceeding the !ast-mentioned num-
ber the general struggle of the young corallites for space
brings about a general displacement of the latter, and ren-
ders it very difficult, and often impossible, to find which
corallites belong together.

Subquadratic or circular sections of coralla with more than
16 corallites are, however, by far not so common as flat, rib-
bon-like coralla which consist of a few or even of only one row
of corallites. The smallest number of corallites in such flat
coralla has been found to be 8, arranged in two rows. Coralla
of this composition are extremely common. The tracing of
their development by successive sections brought out the
fact, that they are the result of a fission of the regularly de-
veloped subcircular coralla, which fission begins when the
latter have reached the stage with 16 corallites. Fig. 11 repre-
sents a corallum of 16 corallites in the act of fission; fig. 12 a
later stage of the same.

After the fission of the whole corallum, a multiplication by
fission of the corallites, on both ends of the bands, sets in, re-
sulting in branches with shoe sole-like (fig. 13) or dumb bell-

Development of Tetradium Cellulosum Hall—Ruedemann. 23

like sections (fig. 14). The rounded ends may separate in toto
(fig. 13) or divide again lengthwise and give off a branch (fig.
14a). The latter process, which is the more common of the
two, together with the fast multiplication of the corallites at
both ends of the bands, produces very broad branches, which,
however, often contain only two and in some places even only
one row of corallites. It is the peculiar appearance of these
bands, which, no doubt, has induced some investigators to
compare TZetradium with Halysites. But, as the develop-
ment of this species shows, the origin of the chain-like coralla
of Tetradium is very different from that of A/alysites the for-
mer originating from a lengthwise splitting of round coralla,
the latter from a continued stolonal gemmation in one direc-
tion.

Figure 15 shows that with the development of larger cor-
alla a general and remarkable decrease in the size of the cor-
allites, and a becoming more irregular of the shape of the lat-
ter are connected. Sections of younger and older coralla
present, on this account, a differing aspect and could easily
be mistaken as representing different varieties or even species
(compare figs. 15 aand b). In sections of older, massive cor-
alla all corallites. are of nearly equal size and their plications of
equal length; multiplication by fission, therefore, has appar-
ently been greatly retarded. As only such sections previously
came under observation, it can easily be understood why the
four fissional plications continued to be regarded as septa or
pseudosepta. With the septa of the Hexacoralla and Tetra-
coralla, they cannot be directly compared, because they have
a different function, serving primarily the multiplication by
fission. Neither can the term “‘pseudosepta,”’ as used by Mose-
ley* for slight plications of the wall of Welopora, which in
number and arrangement are independent from the mesenteries;
be applied here, for the pseudosepta of Hefopora do not de-
velop into fissional partitions and the plications of 7etradium
are too long to have been independent from the mesenteries.

The nature of the plications, therefore, cannot be used
to distinguish Zetradium from Chetetes, the projections of

*Report on certain hydroid, alcyonarian and madreporarian corals
procured during the voyage of H. M.S. Challenger. Voyage of H. M.
S. Challenger, Zodlogy, vol. II, 1881.

24 The American Geologist. July, 1898

which have long been recognized to be the means of fission.
Neither can the chain-like arrangement of the corallites be
used to compare this genus with /falysites.

As a third differential character between Ch@tetes and Te-
tradium the presence of a double wall has been described by
Nicholson. Neumayr remarks that this observation has not
yet been verified. In fact, only a very small percentage of
sections of coralla, in the writer’s collection, show any traces
of a double wall at all. As the figures 1, 3 and 4, well illus-
trate, the walls are formed by closely packed, transparent cal-
cite crystals, the outlines of which are indicated in the figures.
Sometimes one crystal extends throughout the entire width of
the wall. The crystalline nature and the perfect lack of struc-
ture in these walls is the more striking, as the brachiopods
and bryozoans in the same slides exhibit the finest details of
their structure. It, then, would seem, that the walls of Ze-
tradium were homogeneous and simple. But as all walls, with
the exception of the common outer wall, have been secreted
in folds of the ectoderm and hence ,appear as plications of the
outer wall (see figs. 1 and 2), it is evident that they must have
been double originally. A careful scrutiny of the walls re-
vealed indeed the fact that some sections (cf. fig. 8) possess a
dark line extending a short way from the exterior into the
plications, thus demonstrating the amalgamated nature of the
walls. There have also been found a few specimens (see figs.
16 and 16a), in which a dark median line passes continuously
through the walls. It follows a zig-zag course on account of
the secondary plications which branch off on alternate sides
of the primary ones. A stronger enlargement of the walls
shows that the dark median line is caused by the presence ot
the same organic coloring matter which renders the matrix
opaque and which here is deposited in the calcite crystals (cf.
fig. 16a)*.

The conclusion to be drawn from these observations is
that the walls originally were double, that, however, with very
few exceptions, a complete amalgamation took place already
in the earliest stages as proved by sections of excellently pre-

*These dark median lines must not be confounded with the fracture-
lines running quite regularly in the walls in such sections which have
been ground with too coarse emery.

Development of Tetradium Cellulosum Hall—Ruedemann. 25

served young corals (figs. 3 and 4). We have here, there-
fore, relafions similar to those found among the monticuli-
poroids, where also certain forms possess a distinct dark med-
ian line, while in others a perfect amalgamation has taken
place. All these observations must teach that it cannot be a
question of great systematic importance whether the walls of
Tetradium are simple or double, and, that the separation of
Chetetes and Tetradium into two families can hardly be
founded on this.

To sum up, it may be said that, in the writer’s opinion,
the nature of the interior processes, and of the walls, as well
as the mode of growth of the coralla, proves at least this
species of Zetradium to be a chetetide and that Chefetes and
Tetradium are only generically different.

EXPLANATION OF PLATE V.

All figures represent sections of 7etradium cellulosum Hall, sp., from
the Ordovician (Birdseye limestone, lower Trenton) of Ingharm’s Mills,
Bee ¥.

Fig. 1.—Young stage with beginning fission. Magnified 16 diam-
CieLs.

Fig. 2.—Stage with more advanced fission. X 16.

Figs. 3 and 4.—Corallum after the first fission. 16.

Fig. 5.—Corallum with seven corallites, resulting from the fission of
one of the corallites of the preceding stage. X 4.

Figs. 6a and 6b.—Opposite sides of one section (2 mm. thick). Seen
in reflected light. X 4.

6a.—Fission of one corallite nearly completed.

6b.-—Fission of two corallites completed.

Fig. 7.—Stage with completed fission of three corallites. x 4.

Fig. 8.—Fission of all four corallites completed. » 4.

Fig. 9.—Corallite with 4 primary and 8 secondary plications. x 16.

Fig. 10.—Corallite with nearly completed fission. xX 16.

Fig. 11.—Beginning fission of a whole corallum. X 4.

Fig. 12.—Complete fission of the same corallum. 12a cut obliquely.
x 4.

Fig. 13.—-Beginning transversal fission. X 2.

Fig. 14.—Longitudinal fission. X 2.

Fig. 15.—Section through apparently intersecting bands of corallites.
15c cut obliquely. X 4.

Fig. 16.—Specimen showing structure of wall. x 8.

Fig. 16a.—The same. Wall enlarged. X 125.

26 The American Geologist. July, 1898

THE GEOLOGY OF THE ENVIRONS OF ALBUQUER-
QUE, NEW MEXICO.
By C. L. Herrick, Albuquerque, New Mexico.
(PLATE VI.)

It is somewhat surprising that the geology of the valley of
the Rio Grande in New Mexico seems to have escaped atten-
tion, while the more inaccessible parts of the territory have
been the subject of elaborate memoirs. The small area about
the metropolis of New Mexico which forms the subject of
this paper is not wanting in interest from many points of view,
but it seems never to have received more than passing atten-
tion, while the large area of the Mount Taylor district to the
west is the subject of the interesting and elaborate mono-
graph by captain Dutton.

The area covered by this report is, roughly speaking, a
square of twenty miles, with the city of Albuquerque at its
centre. Its study has been carried on in intervals of the ad-
ministrative work of the University and cannot hope to be
exhaustive, yet we trust that a foundation has been laid for
a more minute study of the valley at other places. The at-
tempt to secure information at second hand has proven futile,
for the few who in this region are sufficiently interested to
observe natural phenomena are not well enough versed in the
elements of geological interpretation to report correctly the
facts observed. The writer gratefully acknowledges the as-
sistance of Prof. E. W. Claypole, a former colleague in the
geological study of the Waverly of Ohio, who accompanied
him upon several of the expeditions upon which this paper
rests. Although the conditions here reported are in a sense
local, it is upon the accurate comprehension of these details
that the intelligent survey of the general geological outlines
must rest. A map with contour lines and details of distribu-
tion is in process of construction and will be issued in the
forthcoming bulletin of the University of New Mexico.

I. THe ALBUQUERQUE RIVER DEPOSITS.

The valley of the Rio Grande at Albuquerque offers a
number of interesting geological problems, some of which
when solved may prove of far-reaching importance for the
interpretation of the general surface geology of the territory.

Geology of Albuquerque, N. M—Herrick. 27

To the east of the city, at a distance of about ten miles, the
eastern wall of the valley is formed by a rather abrupt escarp-
ment of gneisses, granites and quartzytes in what may have
been the axis of a monocline. Near the base the abrupt as-
cent is broken by rounded foot hills, and the products of ero-
sion from this granitic metamorphic series are to be found
widely distributed in the valley gravels. Respecting the age
of this formation it is only known that it is older than the
coal measures, limestones of the latter age being everywhere
present at the top of the metamorphic rocks.* In some places
there are pebbles of granite in the silicious layers at the base
of the Carboniferous, and unconformity may be assumed in
inany places, while the resemblance of the silicious strata in-
ierbedded in the limestones to the upper parts of the meta-
inorphic seiies and thé lack of apparent unconformity in some
places suggests that the interval may not have been so long
as has been supposed, or may occur lower in the series—a
suggestion also made possible by the occurrence in the same
relative position in the granite series at Limitar (fifty miles
south) of a band of fossiliferous limestones at a depth of sev-
eral hundred feet below the lime beds of undoubted Carbon-
iferous age. The metamorphic series east of Albuquerque
rises in places to a hight of 2,000 feet above the mesa or 300
feet above the river at the city. The dip is a few degrees (15-
25) to the east, so that the irregularities of erosion as well as
the varying amount of uplift brings the Carboniferous beds at
some places much nearer the mean level. If the mesa east
of the river is really in the axis of an anticline, as has been
suggested, it must be admitted that the western wall has been
entirely removed at this place. If, on the other hand, the
fold was a monocline the whole western portion has been
faulted hundreds of feet below the river level. Nearly oppo-
site Albuquerque the river gravels are much obscured by sand
lrifted from the mesa to the westward which is underlaid by
sands of a relatively late period (Cretaceous).

From five small volcanic cones a small sheet of basaltic
lava has spread over an area of about twenty-five square miles
with an irregular front upon the river of about five or six

*We have been unable to verify the reports of fossils older than the
Carboniferous in any part of the Rio Grande valley.

28 The American Geologist. July, 1898

miles. Along this river front the basalt varies from six to
twenty feet in thickness and is quite vesicular, especially at the
top, and it reposes on substantially horizontal beds of sand-
stone of the same age apparently as that forming the mesa
back from the river, though there are one or more benches
of river drift nearer the river. So far as seen, the material
capped by the basalt does not contain the trachyte, andesyte,
rhyolyte or basaltic pebbles occasionally found in the river
drift, though it contains quartzyte and limestone fragments
and also fossil woods. This point is worthy of careful study,
for by this means it may yet prove possible to ascertain the
age of the eruptives which are so characteristic of the region
further north and south. At any rate, the evidence so far at
hand seems to indicate that the lava flows here are older than
the river gravels, since we have yet to find a place where the
lava overtops the fluviatile formation, while near Isleta we
do find the river gravels overlying the basaltic flows. Much
depends upon the correct estimation of the age of these lava
flows, inasmuch they are said to cover ancient pueblos, and in
some cases maize has been found in a charred state below the
lava. Near Isleta, an Indian pueblo about twelve miles south
of Albuquerque, there is another such a flow and the under-
lying sandy layers have here been greatly indurated and red-
dened. In this case there are at least fifty feet of the Creta-
ceous (?) sandstones and shales below the lava, but the eleva-
tion is not uniform, so that near the southern edge the lava—
there only about eight feet thick—is covered in places by the
river gravels.

Near the northern end of this flow there is an insular
patch of the lava cut off from the main flow by a narrow valley
of erosion which must have been at one time the channel of
the river or an arm of it, and this at a time when the river
was somewhat higher than at present.

These facts with others, the details of which need not be
given here, make it apparent that the local basaltic lava flows
have occurred at a date more recent than the Cretaceous de-
posits beneath them and at a period earlier than that of the
river gravels. Whether the latter are of approximately
Champlain age or not must be left to the future to determine,
but it is a matter of no small interest to ascertain the age of

Geology of Albuquerque, N. M—RHerrick. 29

the several eruptives more definitely in view of the relation
already noted with human remains preserved beneath them.
The possibility that these isolated flows may differ greatly
in age is not to be forgotten, though the essential lithological
and structural similarity of the rocks as well as the similarity
of the methods of occurrence suggest a close agreement in
age.

Having thus briefly indicated the environs or limits of the
river deposits we may turn our attention to the latter as they
are represented at Albuquerque. These beds are exposed at
various points in the immediate valley of the present river.
The banks formed by the erosion of the older flood plain are
often as high as seventy-five feet above the present river bed
below the city. This plain is a large mesa extending from the
bluffs to the foot hills on the east and the surface is nearly
flat but with a gentle upward slope to within a short distance
of the mountains whence the inclination to the base is more
rapid. The uppermost of the deposits of this mesa and that
which lies at or near the surface where un-eroded is a curious
yellowish-white marl, which is apparently about six feet thick
and can be traced at about a constant level in the immediate
river bluffs to a point south of Isleta, as well as north to Albu-
querque and eastward to within a mile or two of the base of
the mountains. South of the arroyo formed by the outlet of
Tijeras canon in the Sandias the mesa is immediately under-
laid by this deposit so that it is thrown out by burrowing ro-
dents. A curious feature of this plain is the occurrence of
numerous slight depressions thickly distributed over the area.
These are rarely more than five yards across and commonly
are from eighteen inches to two feet deep and are provided
with a raised border. They might be taken for buffalo wal-
lows were it not for their great abundance and general dis-
tribution. These depressions seem to hold water as they
sink to the level of the marl. This marl, which may hence-
forth be known as the Albuquerque marl, has been detected
on the western side of the Rio Grande as far south as Belen,
thirty miles south of Albuquerque. The composition of the
marl is largely calcareous, though it contains small pebbles
also. Near the city there has been so much erosion that its
horizon could not be reached for some distance beyond the

30 The American Geologist. July, 1898

University campus, but further south it is quite conspicuous
as a white band near the summit of the bluffs for many miles.
The following is the partial analysis made by Prof. R. W.
Tinsley, chemist of the university.

SO eae ana ae Rents SE es eee NN es Ae 26.53
Gs © Sr.ricte wis ois duals apa petorese Mace gereasctoxsteieecretet 1.20
(OE Clo eae reas sooiccrs sad Coe GmaAGnE 64.47

It will be a matter of considerable local interest to deter-
mine the conditions under which such a marl could have been
formed. If one could find evidence of a dam below Albu-
querque, which at the time when the flood plain had reached
its highest point could have formed a great lake or estuary,
it could be supposed that highly carbonated water from the
limestone areas to the east may have spread over the bottom
this rather uniform layer of calcareous material. The forma-
tion of such lakes or quiet spots on a small scale in the river
valley has other illustrations. Or one might be tempted to
think of wide-spreading flows of volcanic waters charged with
a material sedimented out on cooling. That the marl is not a
purely local deposit is proven by its occurrence on both sides
of the river.

Beneath the marl is a considerable band of gravel and
rounded stones of variable size. The materials are chiefly
quartzytes, gneisses and granites, evidently the debris from
the metamorphic series already mentioned, though fragments
of andesytes, trachyte, rhyolyte and basalt are also found.
In some places the gravels on the east side of the river con-
tain scoria and basalt evidently of the age of the recent cones
of the west side of the river, suggesting an extension of those
flows to the east of the present river. And as fragments of
petrified wood occur with them we may also conclude that
the underlying materials in this place were of the same age
as where exposed elsewhere,—namely Cretaceous. The thick-
ness of these gravels may vary from two to twenty or more
feet. Beneath these appears a sandy loess passing into clay
sometimes carrying fragments of undecayed wood. The
depth of this stratum is as yet but imperfectly known, but it
is eminently characteristic and maybe recognized everywhere
in the immediate bluffs of the river. In some places it has a

THE AMERICAN GEOLOGIST, Vou. XXII. PLATE VI.

Fie. 1. Neck of the Bernalillo voleano.

Fic. 2. Adjacent part of the stratified material showing dykes from the neck and
the disturbed strata.

{IBRARY
OF THE
UNIVERSITY of ILLINOIS,

Geology of Albuquerque, N. M—Herrick. 31

clayey consistency, while more often it is composed of fine
grains of sandy material. About Albuquerque it is in request
as a “molding sand,” for which purpose it is well adapted.
It is plain that this series, which we shall designate as the
“Rio Grande toess,;’ must have been deposited during a
period of abundant but sluggish flow. The great extent and
the horizontality of the series afford proof of these sugges-
tions. The loess seems to repose upon the Cretaceous of the
immediate valley of the river. The original inclination of the
valley must have been greater than at the close of the loess
period, for only ten miles above the city of Albuquerque the
obliquely tilted sandstones of the Cretaceous appear in the
river bed. It appears probable that in many places at least
there is a stratum of coarse material between the loess and
the bed rock, though the only direct evidence we have is from
the reports of well-diggers who report a stratum of “cobble
stones’ as the water-bearing horizon at a depth of 350 feet
upon the mesa three miles east of the University campus.
It may be assuméd that the river silted itself up during the
period of quiet represented by the loess. If so, the re-exca-
vation of the channel must have followed immediately, for,
as above stated, the next number of the series, the “ Azo
Grande gravels,’ is an exceedingly variable quantity. It is
a coarse or moderately fine deposit of the most diverse mate-
rials. Among these the granitic and quartzytic fragments
from the neighboring mountains may be said to predominate,
yet there are localities where the entire deposit is composed of
volcanic scoriz. Ina previous paper the writer has described
the instance further down the river where an isolated basin
has been filled with floating pumice, which deposited by its
own abrasion the so-called Socorro tripoli. A somewhat
similar instance has since been found about nine miles north
of Albuquerque where a large deposit of the same character
may be seen from the train. Large quantities of the dark ba-
salt of the local flows along the valley are noticed everywhere
in these gravels together with rounded fragments of andesyte
and trachyte derived from the older eruptives penetrating the
stratified series of the valley margin. The upper surface of
the loess is everywhere deeply eroded and in the irregularities
so produced are deposited the coarser elements of the gravel.

ios)
No

The American Geologist. July, 1898

Fig. 1, An exposure in the suburbs of Albuquerque showing the eroded upper surface
of the Rio Grande loess with the irregularly banded gravel reposing upon it.
Fig. 1 illustrates such an instance in the banks whence mold-
ing sand has been removed at the eastern end of Lead avenue
in the city of Albuquerque. Not only are the deposits of
gravel very irregularly distributed, but it appears that they are
mostly collected in the centre of the valley or near the pres-
ent river bed. It would seem safe to assume that these
gravels represent a torrential period in the history of the river
and that accordingly this was a period of active erosion, of
numerous changes in the river, and corresponding irregularity
of deposition. The river must have stood at times at a high
level, and it may be that this was a time of breaking away of
old barriers. The loess must have been high enough to have
caused the river to flow over some of the recent lava sheets
of the valley, as is shown by the abandoned channels at vari-
ous places in the lower course of the river. In fact, one is
almost irresistibly reminded of the conditions in glaciated re-
gions, where old river courses are continually being revealed.
Yet in these cases it would seem that the direct agency of ice
is excluded. One such instance is to be described beyond,
while a still more extensive occurrence in the neighborhood of
La Joya may form the subject of a later contribution. It was
at first thought that the river had been dammed at these
points by flows from the adjacent craters, but as further exam-
ination seemed to show that the flows were older than the
loess and certainly older than the gravels which are, in places,

Geology of Albuquerque, N. M—Herrick. 33

found reposing on the top of these flows, and as it seems
necessary to seek some explanation of the superposed marl,
we must probably look for some later agency to account for
‘such dams. Perhaps flooded conditions of affluents below
may give us the clue. It will be necessary to correlate the
above described facts with the conditions existing in the head-
waters of the Rio Grande before all the elements in the prob-
lem can be fully understood, yet it is not hard to see that in
a general way the record is of a river whose upper tributaries
were under the influence of the permutations of the Glacial
period.

II]. Tue IsLETA VOLCANO AND THE Paria MEsa.

In the valley of the Rio Grande in New Mexico is situated
the ancient pueblo of Isleta, well known through the writings
of Lummis, who lived there for some years while studying the
native races. This village is about twelve miles south of Al-
buquerque in the flood plain of the present river, above which
it is raised upon what may have been a natural eminence of
no great hight but which has been added to by accumula-
tions of unnumbered generations. Although the pueblo is
modernized to a great extent it is still inhabited by the same
-race as at the earliest known date, and these Indians eke out
their livelihood, derived from the fields and orchards in the
vicinity, by the sale of pottery and trinkets which the squaws
offer to the travelers on each passing train.

It is not with the village nor its inhabitants that this paper
is concerned, but rather with the interesting geological en-
virons. The Rio Grande is now a sluggish stream as muddy
as the Missouri and nearly as changeable within the narrow
limits of the recent gorge. But the valley is full of evidence
that the river was not always the comparatively tame and in-
effectual irrigation purveyor it now appears. The descrip-
tion of the valley deposits is given elsewhere, and it is only
necessary to say here that the broad valley was at one time
filled to the hight of about 350 feet above present water level,
and data are yet wanting to indicate how much deeper fluvia-
tile deposits may extend. At least three divisions in the river
bluffs have been identified. The base of this “Rio Grande
series,’ so far as known, is a thick bed of loess or fine detritus

34 The American Geologist. July, 1898

of a yellowish color and containing few large pebbles, but a
larger number of what seem to be fragments of granitic de-
bris. The upper portions especially contain numerous white
chalky grains that may be simply the kaolinized remains of
the feldspathic fragments. Although the oldest of these beds,
the loess nevertheless contains fragments of unaltered wood
in some places. The upper surface of this Rio Grande loess
is irregularly eroded and upon this eroded surface there re-
poses a layer of shingle pebbles of considerable though in-
definite thickness. It may be roughly estimated at an aver-
age of twenty-five feet. The upper part of this bed of Rio
Grande gravel is variable in nature, but everywhere in the
vicinity of Albuquerque where the uppermost deposit is pre-
served it is found to support a band of white chalky material
which we shall call the “Albuquerque marl.”

The present gorge of the Rio Grande in the vicinity of
Albuquerque is not more than two or three miles wide in most
places and this small flood plain is dotted with ranches and
villages. From the west at several places the flood plain is
encroached on by abrupt lava-capped bluffs. One such is
adjacent to Isleta and extends from a point just west of the
pueblo for three to four miles northward. The first thought
is that the flow forming the cap has taken place since the river
gravels were deposited, for the material covered is a sandy
and horizontally stratified deposit not unlike the finer forms of
river detritus. The source of the lava, which is a black,
rather vescicular basalt, is near at hand, being a small volcanic
cone about three miles northwest of the pueblo and not more
than three to five hundred feet above the water level of the
river. The eastern wall of the crater has been broken away
and the latest flow has accordingly been toward the sea, in
which direction it may at one time have extended in long
radiating streams from the main sheet as far as the present
river bed, though these outlying portions have long since
been carved down by the river and only great piles of debris
remain, and the greater portion of this material is doubtless
buried beneath the sands. The bluff remaining looking to-
ward the river, is exceedingly irregular, but in hight is quite
constant, being about roo feet at the portions lying to the
north but sinking to less than thirty at the southern limit.

Geology of Albuquerque, N. M—Hterrick. 35

The north and south length of the area is about three or four
miles and the greatest thickness of the lava is not more than
twenty-five feet at any point seen, though the thickness is not
at all constant, but in some places is reduced to four or five
feet. .The appearance of the upper surface shows that there
was not a single wide-sweeping flow, but a somewhat inter-
mittent series following in such a way that the older flows
were in some cases overtopped by later discharges of the same
material. In composition the lava is apparently exactly like
that of the entire series of recent basalts of New Mexico,
which will form the subject of a separate paper. A few miles
further west is a second larger cone, the flows from which
may prove confluent with that of the one now under consid-
eration on the west. It is noticeable that these recent cones
tend to be clustered in groups. The present group may be
known as the Isleta group, comprising an east and west Is-
leta peak. It lies about ten miles south of the Albuquerque
group. But the interest which attaches to this flow is quite
apart from the character of the lava itself. As already indi-
cated, it would not be unnatural to infer, in looking at the
deposits as they lie in the valley apparently parallel to those
formed by the river to suppose that these two are essentially
the same—fluviatile sand and gravel accumulated by the river
at a time when it was larger than at present, or when its bed °
was less inclined toward the south. If this were the case it
would follow that the lava flows might be comparatively re-
cent and such vestiges of man as might be found beneath the
lava need not be assigned any great antiquity. But a brief
study of the sub-igneous deposits in the Albuquerque group
of cones seemed to point to a quite different conclusion. If
they were really fluviatile these deposits were not a part of
what has been called the Albuquerque series, for they are of a
different lithological character. In the modern river gravels
the pebbles are of gneiss and granite as well as quartzyte,
but in addition contain great numbers of fragments: of an-
desyte, rhyolyte and trachyte, i. e., of materials such as are
found in the older eruptives of the valley. So far, these last-
named elements have not been found in the sub-igneous de-
posits mentioned, but fragments such as may have come from
the Cretaceous of the region to the west, if not of that age

36 The American Geologist. July, 1898

themselves, are commingled with the granitic debris. But in
the midst of the perplexity growing out of the evidence that
the river erosion of the time when the present gravels were
deposited has involved these lava-topped bluffs, the study
of the material below the lava of the Isleta cones has offered
an unambiguous solution of part of the problem. At that
place indeed the recent river gravels (No. 2 of the Albuquer-
que series) are in places to be seen actually overlying the lava
and forming extensive beds upon its surface. On the other
hand, as stated elsewhere, fragments of the lava and of pumice
have been found in No. 2 on the opposite side of the river,
An examination of the materials below the flow at Isleta
shows that they are largely composed of sand grains of ap-
parently granitic origin. They are mostly quite fine and only
rarely do large pebbles occur. Close inspection shows that
in many places there is a large admixture of small black grains
of a rather obscure nature. Fortunately a place was found at
a point nearly due east of the crater where the whole mat-
ter is explained. Here the thickness of the underlying gray-
els is exposed for about fifty feet, and the lava is very irregu-
lar. In some places it is fifteen to twenty feet thick and in an
adjacent part it is less than five, while in other places the lava
never has flowed over the gravel beds. The latter, in those
portions in which they are, or have been, covered by the lava,
conforms to the irregularities of the under-surface of the flow
so that, as the deposits are very clearly and minutely stratified,
there is no question of erosion prior to the flow sufficient to
account for the irregularities. Different parts of the stratified
gravels are unconformable to each other, as might be in a
current of changeable character with great burden of detritus.
But the clue to the nature of these deposits is found in the fact
that in the midst of this stratified deposit and _ scattered
through it from top to bottom of the entire exposure are large
angular blocks of basalt quite like the material of the flow and
varying in size from the diameter of one’s head to that of a
pea, arranged irrespective of stratification, though in some
places there are bands filled with small grains of a similar
character. The appearance of the exposures is curious in
the extreme for the mass is so minutely stratified and its ma-
terials so plainly the detritus of sedimentary deposits that the

Geology of Albuquerque, N. M.—FHerrick. 37

agency of water is proven, while the arrangement of the an-
gular blocks is like that of glacial boulder clay. The inclina-
tion of the strata is slight but obviously in a direction radiat-
ing from the cone of eruption. It would be natural to think
of volcanic ash or mud but the materials do not admit of this
conclusion. We are shut up to the view that at the time
immediately prior to the last eruption of the Isleta crater
there was a great out-flow of water from the crater, accom-
panied by explosive fragmentation of pre-existing lava whose
pieces were either intermittently thrown from the crater to be
lodged in the pasty mud hurried along by these flows, or
caught up in the current and after lodging by their own
weight, finer material was settled about them in the process
of sedimentation. This mud-flow evidently extended beyond
the subsequent flow of lava, for such banks are exposed with
their freight of lava blocks but without the settling and dis-
tortion resulting from the weight of the lava. Incidentally
it may be learned that the lava flow followed soon after the
water, for it can easily be seen that the weight of the lava
caused great displacement, especially near the edge where the
still pliant material was squeezed beyond the edges. The
upper surface of the sand is baked and browned more than in
other places, and a great deal of silicilous matter has been in-
<orporated into the under layers of the lava, thus proving the
presence of water at the time of the flow. The finer particles
of basalt were, of course, carried according to the same law
as the other ingredients of the material caught up by the
gushing waters. Much yet remains to be done in ascertaining
the extent of the deposits from such floods. That the quan-
tity of water must have been enormous is plain when we note
that nearly a hundred feet of the material certainly was de-
posited over many miles, while the actual thickness may have
been much greater. (Figs. 1, 2 and 3.)

This instance has a special significance in establishing the
fact that in connection with the lava flows of the basaltic series
there occurred great floods of hot water which may well have
been highly charged with gases and silica. Thus it seems
possible to account for the great areas covered with silicified
wood in the western part of the territory and Arizona. Such
great floods would undoubtedly produce lakes of silicious

38 The American Geologist. July, 1898

Fig. 2. The Isleta voleano. In the middle ground the abrupt escarpment of the
lava-topped mud flows from the volcano.

! iM Hine Hill) Wainy ae Ti.
au ale 1 ini Ae ie nee aos
— May la by f a
: Rt cal ae f

A —s aA y ian Wi

isi Me

Fig. 3. Portion of the same as shown in figure 2 to show the fragments of basalt
scattered in the stratified mud.

water in which trees might become impregnated with silica,
or more probably a mass of such pasty material charged with
silicious water would be a still better means of altering im-
bedded trunks. Of course, the age of: these flows is still to
be determined, though it may safely be placed at an earlier
period than that in which the river gravels were deposited,
that is, earlier than the post-glacial or Champlain period. It
would appear that the silicification of the forest beds must
have been in a general way contemporaneous with the sand
accumulations, but the trunks are sometimes found in sand-
stones supposed to be not later than the Cretaceous. Still
further, the finding of ears of corn imbedded in the lower sur-
face of the flow of lava in certain places might then be thought
to take human occupation back to that period, but it is plain
that at present no such wide generalization is warrantable,
though the above-mentioned facts point the way to the final

Geology of Albuquerque, N. M—Herrick. 39

settlement of the larger question as to the age of man in New
Mexico.
The Paria Mesa.

In connection with the flow at Isleta above described,
another problem is to be noticed. About two and a half
miles north of Isleta a part of the lava-topped mesa extends
far out into the valley. It is here nearly one hundred feet
high, though the lava is rarely more than ten to fifteen feet
thick. (Fig. 4.) The talus is very steep. This area of about

fia. 4. The Paria mesa. The old river channel is to the left.

one quarter mile in length and a little more than one-half
that in width has been cut off from the rest of the area by what
must have been an arm or old channel of the river at its high-
est. This cut-off is nearly north and south in its course and
is blocked at its northern end by bars, part of which may be
due to drifting sand and more to bars accumulated when the
river swept in an arch near the entrance, as there is evidence
that it did at no very remote period. The bluffs of the west-
ern bank of the river are here a considerable distance further
west than the opening of the old channel, and there are rem-
nants of both the loess and the gravel deposits, i. e., numbers
one and two of the Albuquerque series. Similar gravel is
found on the summit of the mesa. Near the northern end of
the old channel is the small village of Paria, and the town is
supplied from rather shallow wells, showing the existence of
the river channel at that place. This ancient channel raises
the interesting query as to the conditions which could have

40 The Amenean Geologist. July, 1898

resulted in so blocking the main channel as to cause the
stream to cut through this solid mesa. May it have been that
the flow of mud due to the water from the volcano dammed
the stream and caused this side erosion, or, what is more
probable, that the filling up of the old valley by the loess and
then the gravel lifted the level of the entire valley so high that
the water found its way over the lava area and then, when the
gradual removal of the glacial detritus below reduced the
level, the water wore through this sheet of lava and excavated
the new channel before that removal had opened up its old
channel. :

In this connection it may be noticed that upon the sum-
mit of this insular mesa there is what seems to be the rem-
nant of an aboriginal fortification consisting of two walls of
stone meeting at a right angle to the northwest, the longer
extending south about 100 yards, the other east about sev-
enty-five yards. At present the walls are loose ridges of lava
blocks about six feet high and ten to fifteen feet wide. There
is some evidence that the ground on the inside near the wall
has been excavated several feet. The outline of only one
pueblo of small size could be seen within the area thus partly
protected, though chipped flints and potsherds are numerous.
It seems hardly likely that the embankment was raised against
water, and, in fact, there is at the angle an opening in the west
wall like that of a sally port or door. The basaltic walls of
the mesa and fragments at its base are covered with aboriginal
tracings in which the figure of the turtle and the four pointed
star seem predominant.

Ill. THr BERNALILLO VOLCANO.

The town of Bernalillo is sixteen miles north of Albu-
querque on the east bank of the Rio Grande. At this point
the Cretaceous emerges boldly from beneath the river gravels
and loess. All the river deposits betray the influence of the
Cretaceous below some time before the latter actually out-
crops. Opposite the town and for some miles to the north-
ward the river is bordered by long horizontal bluffs capped
by basaltic flows of no great thickness, but of many miles ex-
tent. These bluffs afford the most instructive illustration of
base-leveling that could be imagined. (Fig. 5.) The basalt re-

Geology of Albuquerque, N. M—Herrick. 41

Fie. 5. More distant view of the neck of the Bernalillo voleano and the
lava-topped mesas beyond.

poses on the red and grey Cretaceous strata, which remain
nearly horizontal. The sources of these flows is not difficult
to locate in local craters which penetrate the Cretaceous at
various places. The erosion of the river has done a very use-
ful service to the geologist, in removing, to a large extent,
the soft strata about one of the old cones and exposing the
true inwardness of the eruption when occurring in soft ma-
terials. In fact, it may be said to afford the necessary supple-
ment to the data from the Isleta volcano. Here, as in that
case, the lava forced its way through the soft Cretaceous
strata, and here also the outbreak seems to have been attended
with a great flood of hot water which has redistributed the
materials. In one place (Pl. VI., Fig. 1) erosion has exposed
the “neck” or original column of lava which cooled in the
throat of the crater, and one may see the long dykes of basalt
radiating in various directions into the soft displaced sand
(Pl. VI., Fig. 2). These radiating dykes formed ribs to which
the plastic sand mixed with fragments of the basalt adjusted
itself. In the vicinity of these dykes there is often a small
amount of metamorphism roughly proportionate to the
thickness of the intruded mass. There is much reason to
suppose that the other volcanoes of the valley are not later
than these mentioned.

42 The American Geologist. July, 1898

In the immediate environs of Albuquerque there are no
complete exposures of the Cretaceous, but at a point on the
west side of the Rio Grande about three miles northwest of the
bridge at Los Corrales there is a fairly good continuous ex-
posure of sands and marly lime referred to this period. The
rock is very slightly coherent—scarcely more than a crag—
and occurs in bands of red, yellow and white, while near the
top is a narrow band of lime containing some imperfect re-
mains which have not yet been studied. . The entire thickness
exposed is rather over one hundred feet, of which the lower
half is of red sand with nodules of greater consistency. Some
layers are quite firmly cemented. Near the top of the light-
colored division the sand is loose and contains numerous peb-
bles of red and black chert, quartz, quartzyte and other ma-
terials apparently of granitic origin. It appears that this Cre-
taceous series is the country rock back from the river and that
it has furnished a large part of the materials for both the
older and the more recent river deposits. The valley nearer
the river at this point is filled with materials similar to the
portion about Albuquerque, the loess being below and over-
topped by coarser material deposited on the eroded surface of
the loess in sand-bar formation of the most interesting sort.
Prominent among the coarser materials are fragments of
basaltic lava evidently derived from flows higher up the river.
No such material is seen in the Cretaceous gravel beds. Re-
specting the latter it may be noted that these beds are similar
to those occupying the hills northeast of Socorro, where they
are conspicuous by reason of their colors and stratigraphic
distinctness.

IV. THe ALBUQUERQUE VOLCANIC GROUP.

A good illustration of the circumscribed lava flows from
the latest eruptive cones is seen about six miles west of Al-
buquerque. Here five small cones rise in a group from the
western crest of the valley. The axis of the group is north
and south. Each cone may be the core or plug of the orig-
inal crater, but, in that case, the walls of the crater proper
have disappeared. It is claimed that there are evidences of
local heat and vapors, but of this we have no evidence. The
lava is a black vesicular basalt, and it extends in all directions,

Mecklenburg or Baltic Moraines—Upham. 43

but especially to the east and south in an irregular sheet for
several miles. Probably the greatest extent 1s not more than
five miles from the cones, though the abrupt face as seen from
the river is probably six miles long. The inclination of the
flow is slight, not over two or three degrees, and at the ex-
posed margins the thickness is often less than ten feet, though
at points nearer the cones the thickness is somewhat greater.
It is a matter of some surprise that so thin a flow should have
proven so long fluid as is implied by the great extent of nearly
ievel country covered. In some places the river has exposed
a nearly perpendicular bluff over fifty feet high capped by this
flow, and with the sides and base protected by the angular
blocks. Along the southern face, on the other hand, the
slight erosion of arroyos has served to expose the underlying
strata of sand and gravel without having displaced much of
the lava, as is proven by the relatively limited talus and the
uncovered strata of adjoining hills. These strata differ from
the recent fluviatile deposits in appearance and contents. The
upper portion is but slightly indurated and the pebbles in-
cluded in it are largely quartzyte, chert and lime. The beds
are horizontal but differ from those nearer the river which
contain materials like those which are derived from the gran-
ites and gneisses of the Sandias to the east. Fragments of
silicified wood occur in the beds covered by the lava. They
may, therefore, be of Cretaceous age, though it will be an in-
teresting problem to determine whether the flow at other
points did not run over the river gravels.

{European and American Glacial Geology Compared, VI.]

THE MECKLENBURG OR BALTIC MORAINES.

By WARREN UPHAM, St. Paul, Minn.

Ridged and hilly marginal drift accumulations, extending
in a curved and looped course, form the most conspicuous
topographic features of Denmark and northern Germany.
The belt which bears these drift hills, partly in a single series,
but in other parts comprising several approximately parallel
or interlocking series, was traced along its entire extent
through Germany by Prof. R. D. Salisbury in 1887, who first

44 The American Geologist. July, 1898

recognized it as a terminal morainic belt, similar to the ter-
minal moraines of the northern United States.* This most
prominent European moraine series reaches nearly 300 miles
from north to south and southeast in the peninsula of Den-
mark, Schleswig, and Holstein; and thence it continues east-
ward about 500 miles in broadly crescentic loops, passing
through Mecklenburg, Pomerania, and West and East Prus-
sia. Its course in these German provinces, to the Russian
frontier, as outlined by Salisbury, has since been in part fully
explored and mapped by Wahnschaffe, Keilhack, and other
German geologists, especially for distances of 50 or 60 miles
both to the west and east of the river Oder. Immediately
eastward of that river, a great moraine loop incloses the
southern and eastern sides of an area Of most remarkably abun-
dant drumlins.t

On account of the general parallelism of this moraine belt
with the coast of the Baltic sea, and because its drift was trans-
ported by an ice-sheet flowing across the Baltic basin toward
the west and south, it is commonly called the Baltic ridge.
From its good development in Mecklenburg, Prof James
Geikie has applied the name Mecklenburgian to the epoch or
stage of the Glacial period when its morainic drift was
amassed.{ In North America a correlative and probably con-
temporaneous stage of glaciation produced the great series
of moraines which has been mapped from Nantucket and
Cape Cod to Wisconsin, Iowa, Minnesota, the Dakotas, and
the Canadian provinces of Manitoba and Assiniboia. The
Late Glacial time of accumulation of these moraines had been
somewhat earlier named by Chamberlin the Wisconsin
epoch or stage;§ and this term, as I have shown in a former
paper, || may be better used, in accordance with the law of
priority, for the moraine-forming stage of the Glacial period
in Europe as well as in America.

My first observation of the Baltic ridge last summer was

*Am. Journal of Science, third series, X XV, 401-407, May, 1888.

y+Noticed in my third paper, Am. Geologist, X XI, 237, April, 1808.

{Journal of Geology, III, 241-269, April-May, 1895.

$Chapter XLII in Geikie’s Great Ice Age, third ed., 1894; Journal
of Geology, III, 270-277, April-May, 1895.

Am. Geologist, XVI, 100-113, August, 1895.

Mecklenburg or Baltic Moraines —Upham. 45

on the railway route from Hamburg to Oldesloe, Lubeck,
Kleinen, Biitzow, Rostock and Warnemunde, passing through
Holstein and Mecklenburg on the way to Copenhagen and the
Scandinavian peninsula. Again, returning from Goteborg
(Gothenburg) I crossed the northern part of the Kattegat to
Frederikshavn, the most northern port of Denmark, and ex-
amined the moraine belt in its fine development near that
town. Thence it was observed from the railway in passing
west to Hjorring and southward through the whole length of
this peninsula.

From these observations it appears certain that the Baltic
ridge was formed when the border of the European ice-sheet
rested on the eastern part of Schleswig and Denmark as far
north as Frederikshavn, being there indented by a great re-
entrant angle, from which the ice-front extended westward,
resting on the northwest coast of Denmark, and thence proba-
bly extending southwesterly across the area of the North Sea.
On the east coast of Yorkshire in England an apparently cor-
relative moraine, described by Prof. H. Carvill Lewis and by
Mr. G. W. Lamplugh, is well defined along a distance of
about seventy-five miles northward from the mouth of the
Humber, past Bridlington, Scarborough and Whitby, formed
by an ice-sheet which spread from Norway and Sweden across
the North Sea basin. In England and in continental Europe
alike, as also in North America, wide areas of glacial drift lie
outside the moraines, reaching’ south nearly to the Thames
at London and to Brussels and Dresden. In America neither
the maximum Kansan extension of the ice-sheet, nor, after an
interglacial retreat, its second great lowan advance, was nota-
bly attended with moraine accumulation; but, during the en-
suing Wisconsin or Champlain epoch of final recession, many
conspicuous moraines, like these west and south of the Baltic
and others farther north in the island of Seeland, in Sweden,
and in Finland, were amassed at many lines where peculiar
conditions of the waning ice-sheet favored the deposition of
much marginal drift.

Prominent moraine hills rising 100 to 150 feet above the
adjoining country, to altitudes of 200 to 300 feet above the
sea, extend fifteen miles from the coast of the North sea at
Lonstrup east by Hjorring to Sindal. Thence southward

40 the American Geologist. July, 1898

thirty miles to the Limfjord at Aalborg, moraine drift covers
the eastern half of this northmost part of Denmark, its highest
hilltops being 300 to 440 feet above the sea level. The north-
east boundary of the moraine belt is about two miles south-
west of Frederikshavn, at a hight of about 100 feet; and with-
in a mile farther southwest one ascends 200 feet, or more,
upon typically morainic, irregularly grouped hills of till, con-
taining abundant boulders, many of them granitic, up to three
feet and occasionally five or six feet in diameter. As the un-
derlying formations of Denmark comprise only Cretaceous
and Tertiary strata, the granitic boulders are known to have
come from the great Archzean region of Sweden and Norway.
The contour of these hills and of all the country within the
view for many miles westward and southward is wholly mo-
rainic, presenting a multitude of irregular hills and ridges,
which rise generally forty to seventy-five or one hundred feet
above adjoining hollows and twice as much above the stream
valleys. Nearly all the area is under cultivation, excepting
occasionally a very bouldery knoll or hillside; and many of
the farmhouses are quite picturesquely ensconced among the
moraine hillocks or in partly wooded ravines. In a walk of
some eight or ten miles upon this tract, I found its material al-
most wholly till, everywhere having plentiful boulders, with
very scanty kame gravel and sand, or none; but in many parts
of the belt southward, it consists largely of kame deposits,
usually in smooth massive hills similar to those of the prin-
cipal terminal moraine on Long Island in its course east from
Roslyn. Between Frederikshayn and the Limfjord the width
of this compound moraine belt is fifteen to twenty miles.
Continuing southward, this belt, diversified by frequent
small lakes, occupies in general the eastern third or half of
Denmark. It attains its greatest altitude in the broadly
rounded hill named Ejer Bavnehoj, 564 feet above the sea,
seen within two miles west of our railway and probably 200
feet above it, a few miles southwest of Skanderborg. Drift
covers nearly all the peninsula so deeply as to give no out-
crops of the underlying formations; and west of the morainic
till it is described as mostly stratified gravel and sand, in undu-
lating swells and in plains sloping away from the moraine belt.
Through Schleswig our railway, passing south from Lun-

Mecklenburg or Baltic Moraines—Upham. 47

derskov by Woyens, to Flensburg, Schleswig and Rendsburg,
traverses a slightly undulating plain of modified drift, mainly
varying in altitude from 100 to 250 feet above the sea, but de-
clining southward to only twenty-five feet, or in part less,
beside the river Eider and the Kiel ship canal at Rendsburg.
The west border of the morainic hills lies from three to five
miles east of the railway along this distance of about eighty
miles; and they rise prominently above the plain in a well de-
fined and continuous series from Flensburg southward, their
tops being 200 to 350 feet above the sea.

In Holstein the principal line of morainic accumulation
curves southeast, east and northeast, past Neumtnster and
Eutin, forming an interlobate series of hills, some of which
rise 400 to 500 feet above the sea within a dozen miles north
and northeast of Eutin. Thence turning back to the south-
west, south and southeast, past Segeberg, this principal mo-
raine occupies a width of about six miles where it is inter-
sected by the Hamburg-Libeck railway, from one mile south-
west to five miles northeast of Oldesloe. Here it has a typical
contour of irregularly grouped hills and ridges, 50 to 100 feet
above the intervening depressions; and its material is mostly
gravel and sand, boulders being rare on its southwestern part
but frequent northeastward.

Passing through Lauenburg and Mecklenburg, this great
moraine, in width and hight similar to prominent portions of
the moraines of the United States, resembles them too in the
loops of its course, convex southward, with especially massive
accumulations on its interlobate tracts. It sweeps from Olde-
sloe southeast, east and northeast, past Molln, Boddin and
Crivitz; is crossed by the railway between five and ten miles
west of Butzow, and thence extends re-entrantly north past
Kropelin to the Baltic shore ten to fifteen miles west of War-
nemunde. Returning toward the southeast, it is again inter-
sected by the railway between one and six miles north of
Schwaan, whence it continues southeast to the moraines
which have been mapped west and east of the Oder. Such
grand loops also characterize this belt in its farther extent past
Neustettin, Dantzic, Ortelsburg and Lyck, to the international
boundary.

Having held a conspicuous development across northern

48 The American Geologist. July, 1898

Germany, the Baltic ridge will quite surely be found traceable
far onward in Russia. If we follow the outline of the country
bearing frequent or abundant lakes, so generally coextensive
with the late glacial drift and its moraines, whether in North
America or Europe, we pass from Prussia northeast to the
Valdai hills, which are the most prominent elevations in cen-
tral or western Russia, although at their highest points only
about 1,100 feet above the sea. These hills are described by
Nikitin as composed of morainic drift. The border of the
lake-dotted country leads us still forward northeasterly to the
Arctic ocean near the middle of its Russian coast, somewhat
east of the White sea. I can not doubt that distinct lines of
marginal drift will be traced, when carefully looked for, along
this distance of about 1,300 miles, completing an outline of the
border of the European ice-sheet when its rapid final melting,
attended with the formation of great marginal moraines, be-
gan.

Along all its course, from the British Isles, across the
North sea, through Denmark, Germany, and Russia, this
boundary of the moraine-bearing drift, as in North America,
lies at a considerable distance back from the drift limits of
earlier glaciation. It testifies that the conditions under which
the marginal drift ridges and hills originated, during stages in
the general retreat of the continental ice-sheet, were depen-
dent on the great climatic change brought about by the de-
pression of the ice-covered parts of both continents in the
Champlain epoch. Then the borders of the ice-sheets. on
account of their marginal melting, presented steeper slopes
than before; much of their englacial drift became superglacial;
and the deposition of the drift at the ice-front, both beneath
and upon the margin of the waning ice-fields, was promoted
by vigorous glacial currents, which, however, were surpassed
by the rapidity of the summer melting. The moraines, in
their parallel succession, were amassed with only short inter-
vals of time separating them, as compared with the prolonged
earlier stages of the Glacial period.*

*The general conditions of accumulation of marginal moraines are
discussed in my former papers in the Am. Geologist, XVI, 107-113,
August, 1895, and XIX, 411-417, June, 1897. For the Baltic ridge,
German geological opinions of the time and manner of its formation
have been well given by Dr. Wahnschaffe in his work reviewed by
Prof. Salisbury in the Am. Geologist, IX, 294-319, May, 1802.

Review of Recent Geological Literature. 49

In my correlation of the Baltic ridge westward with the
British moraines of Lewis and eastward with the Valdai hills
and the limits of plentiful lakes in northern Russia, | differ
from the mapping of DeGeer and Geikie. Instead of the
southwestern boundary given for the “Baltic glacier’ in the
new edition (1894) of Geikie’s “Great Ice Age,” another mar-
ginal moraine, which should probably be correlated with De
Geer’s Swedish boundaries of the Baltic stage in the glacial
recession, extends, as I observed it, across the island of See-
land (Zealand), passing northwestward from the ice-crushed
hills of Rugen and Moen to Hammer and Nestved, thence
northerly to the peninsula between the Ise fjord and Roskilde
fjord, and thence northeastward to Helsingér (Elsinore),
where it connects with the line traced by DeGeer across
Scania, the southern extremity of Sweden. With this boun-
dary we may, following DeGeer, correlate the more northern
moraine which crosses the Wetter and Wener, and his mo-
raine on the island of Oesel, and the moraines of Finland; but
these belong, according to the conclusions of this paper, to a
later recessional stage than the moraines of the Danish penin-
sula and of Mecklenburg and Prussia, which are well named
by glacialists as the Baltic ridge.

‘

meV LEV OF RECENT: GEQ@EOGICAL
12 ee Peeks LST ee

Geology of the Yukon Gold District, Alaska. By Jostan Epwarp
SPuRR. W2th an Introductory Chapter on the History and Condition of
the District to 1897, By HAROLD BEACH GoopricH. (From the Eigh-
teenth Annual Report, U. S. Geol. Survey, Part III, pp. 87-392, with
plates 32-51, and figures 7-25 in the text. Washington, 1898.)

The field work on which this report is based was done in the sum-
mer of 1896 by the author, with H. B. Goodrich and C. F. Schrader
as assistants. The oldest rock formation in the gold region is granite,
usually more or less schistose or gneissic, and sometimes passing into
mica schist. Next in ascending order is the Birch Creek series.
roughly estimated as possibly 25,000 feet thick, consisting mainly of
quartzitic rocks, generally thin bedded or schistose, with abundant
quartz veins, which carry gold with pyrites and sometimes galena.

Above the Birch Creek series, and in general closely associated with

0 The American Geologist. July, 1898

unr

it, is another thick series of rocks, named the Fortymile series because
of its development on the creek of this name. The latter series includes
alternating beds of marble, from a few inches to fifty feet thick, and
quartzitic and other schists, with dikes of eruptive granites and diorites,
and with many quartz veins.

These two rock series, which are regarded as the principal sources
of gold in the placers, are known to be older than the Carboniferous
end Devonian formations of the Cordilleran mountain system, and are
thought to be pre-Cambrian. The numerous younger rock series of the
region, and the placer gravels which are the chief object of interest to
prospectors in the present stage of development of the gold mining,
are also very fully described.

The report relates chiefly to the Alaskan possessions of the United
States, but comprises also incidental notes of the Klondike district on
the British upper part of the Yukon. It is accompanied with many
maps and sections, and will be of great service to prospectors. For
their convenient use, also, an abstract of the two Alaskan reports here
noticed has been prepared, as a separate and abridged publication of
the U. S. Geological Survey, by Dr. S. F. Emmons, in 44 pages, with
a large map of Alaska and descriptions of the routes to the gold fields.

WwW. U.

Studies on Cambrian Faunas. By G. F. MaTTHEW. (Trans. Royal
Soc. Canada, 2nd ser., vol. 3, sec. 4, pp. 175-211, pls. 1-4, 1887.)

This essay is divided into two parts; the first treats of a new sub-
fauna of the Paradoxides beds of the St. John group, the second de-
scribes certain of Billings’ Primordial fossils of Vermont and Labrador.
The fauna described in the first part of the paper is claimed to be equiv-
alent to that of the upper Paradoxides beds of Sweden. Among the
fossils is a genus not heretofore recognized in America, viz. Angelin’s
genus Dolichometopus. Several species of Dorypyge occur in this fauna,
also species of nomocare. The prevailing species of Agnosti are
Longifrontes, Brevifrontes and Leevigati. Several new species of
A grautlos, one of Liostracus, one of Conocoryphe, one of Ptychoparia
and one of Dorypyge are described. Many species of the fauna have
representative forms in Bohemia, Great Britain, etc.

The author claims that he has established a close relationship be-
tween this fauna and that of Olene//us through the genus Dorypyge
and other types, and suggests that here may be the proper stratigraphi-
cal place for it, rather than below the Paradoxides beds.

The second part of the article is taken up with a description of such
species of Billings’ Primordial fossils of Vermont and Labrador as were
studied in connection with the Cambrian fauna above described. The
investigation induces Dr. Matthew to think that Billings’ species should
be classed as Middle rather than as Lower Cambrian. This opinion
appears to be based on the presence of the genera Bathyuriscus (allied
to Dolichometopus), Dorypyge and Anomocare.

Four plates of figures are given of the new species and varieties
of the new subfauna, and of the species of Billings’ Primordial fauna
fossils that are discussed in this paper. G. F. M.

Review of Recent Geological Literature. 51

Paleontologische und stratigraphische Notizen aus Anatolien. J.
Der Lias am Kessth-tash W. von Angora, etc. Von J. F. POMPECKJ,
in Miinchen.*

This article describes the several zones. of the Lias_ recog-
nized near Angora in Anatolia. The first part isa description of the
fossilsfound. Foraminifera of the groups 7exularide and Rotalide were
met with; also He/iodiscus among the radiolarians. Crinoids of the genus
Pentacrinus (E-xtracrinus) form a part of the collection. A Zerebratula
was obtained, also a Pleurotomaria (P. cf. amathez Quenst.). Cephalo-
poda form an important part of the fossils gathered. The species are
Phylloceras frondosum Raynes, P. herbertinum Raynes, P. alontinum
Gemmellaro, Lyfoceras sp. ex. aff., L. ampli Opp., Arietites cf. rotator
Raynes, 4. cf. /atisuldcatus Quenst., Belemnites sp. indeterm.

A study of these species leads Dr. Pompeckj to assert the presence
of the Lower, Middle and Upper Lias at Kessik-tash, and comparisons
are made with the Lias of the Mediterranean and northwest areas in
Europe.

An interesting part of the article is a discussion of the relations
of land and sea in eastern Europe and western Asia in the Liassic age.
Dr. Pompeckj postulates the existence of an island whose area cov-
ered the Archipelago, eastern Greece and Thrace and the Balkan re-
gion in the time of the Lias. This island was separated from a north-
ern mainland by a narrow strait in eastern Hungary. The northern
land is called the South-Russian mainland and the sounthern boundary
includes the mouths of the Danube, the Crimea and-the plains north
of the Caucasus; from this range the boundary swept around to the
south and included the valley of the Caspian sea. Asia Minor and
Persia thus formed a marine region, but there was a free connection
between it and the Mediterranean area, as there was no independent
fauna in the eastern sea.

The existence of a northern mainland is further strengthened by
the presence of a Rhetic flora in the Alburz mountains of northern
Persia which, according to Dr. Pompeckj, is here the northern bound-
ary of the Liassic sea.

The article is furnished with a map showing the geographical feat-
ures above indicated, and with three plates bearing figures of the
species found at Kessik-tash. G. F. M.

History of Mining and Quarrying in Minnesota. By WARREN UpP-
HAM. (Minnesota Historical Society Collections, vol. 8, pt. 2, pp.291-
302, May 10, 1898.)

The substance of this paper was delivered as an address at the
annual meeting of the Minnesota Historical Society, Jan. 18, 1897.
The paper deals with the various substances which have been or which
are mined or quarried in the state and gives a brief account of the
development of the industry connected with each. The subjects treated
are: copper, gold, iron, coal, granite and gneiss, quartzyte and sand-
stone, limestone, clay. Some statistics are presented and there is also
a popular resumé of the geological history of Minnesota. U. S. G.

a Deutchen Geologischen Zeitscrift 1897. Pt. 4 pp. 713-828. 2 cuts, 1 map, 2
plates,

52 The American Geologist. July, 1398

The Valley Regions of Alabama (Paleozoic Strata). By HENRY Mc-
CALLEY, Assistant State Geologist.—Part I. The Tennessee Valley Re-
gion. Pages 436, with Plates I-1X, and four figures in the text ; 1896.—
Part II. The Coosa Valley Region. Pages 862, with Plates X-XXXV,
and figures 5-18 in the text ; 1897.

These are reports of the Geological Survey of. Alabama, which has
been doing excellent work, under the direction of Dr. E. A. Smith,
during twenty-five years. They describe the northern two-fifths of the
state, in which its chief mineral resources are found, including the rich
deposits of iron ores and coal which have been extensively worked in
the Birmingham district. The strata of the Coosa region, folded,
faulted, and eroded, form the southwestern end of the great Appalachian
mountain belt, with much picturesque scenery. Northward the geolog-
ical structure changes until the rocks are nearly level in stratification;
but they have been eroded by the streams to form great plateaus, some
of which rise 1,200 feet above the valleys, or 2,000 feet above the sea,
being the highest land in the state. After general descriptions of the
two regions, each is treated in much detail in chapters describing the
several counties. The formations range in age from the Cambrian to
the Carboniferous, and are illustrated by twenty-eight sections which
cross the Coosa region from southeast to northwest, nine of these
sections being continued across the Tennessee river. W. U.

Summary Report of the Geological Survey Department [of Canada|
for the year 1Sg7. 156 pages: Ottawa, 1898. Price ro cents.

Fifteen field parties were employed by this survey last year, two
being in British Columbia, two in the Northwest Territories (engaged
in experimental borings for petroleum and natural gas in the Athabasca
and Saskatchewan region), four in Ontario, one in the province of
Quebec, one in New Brunswick, three in Nova Scotia, and two on the
shores of Hudson strait. Extensive deposits of corundum, which will
probably be of economic importance, have been found, as here de-
scribed and mapped, in Hastings and Renfrew counties, Ontario. The
West Kootenay mining district and other gold-bearing areas north of
the Lake of the Woods and of Rainy lake and in Quebec, New
Brunswick, and especially Nova Scotia, have been examined and are
somewhat fully noted, for the guidance of prospectors.

Along the St. Lawrence valley the Late Glacial lacustrine and
marine shore lines have been traced by Mr. Robert Chalmers, who also
has further investigated the glaciation of that region. He concludes
that earliest a northwardly flowing ice-sheet extended from the moun-
tainous southern watershed to the St. Lawrence; that later the very
thick Laurentide ice-sheet, moving southward, overflowed the whole
valley (and it may be added that it carried boulders, as shown by Prof,
C. H. Hitchcock, to the top of Mt. Washington and across the Green
mountain range); that this was succeeded by local glaciers flowing
down from the highlands on each side of the St. Lawrence valley; and
that lastly floating ice produced a general southwestward striation in
the valley during its Champlain marine submergence. It is admitted,

Authors’ Catalogue. 53

however, that these valley strize running southwest may be attributable
to deflection of that part of the Laurentide ice-sheet at its time of final
melting, which interpretation seems to the reviewer more probable.
According to this view, the western front of the ice-sheet that covered
the St. Lawrence valley, holding a glacial lake on its southwest side,
retreated northeasterly along a great extent of the valley and remained
latest in the vicinity of Quebec or farther east, finally disappearing from
the valley while yet large tracts of ice enveloped the higher country on
the south and north. Ww. -U.

Das Paleozoicum Polnischen Mittelgebirge. By DR. GEORGE
GuricH. (Trans. Imperial Mineralogical Society of Russia, vol.
Xxx, 1806.)

The district described in this memoir is in southern Poland, mainly
in the country between and around Kielce and Opatéw. This region
has been subjected to considerable oscillation, and the rocks are folded
and faulted to a marked degree. The geological section extends from
the Cambrian to the top of the Devonian, and the strata reach their
greatest development in the Devonian. The Cambrian is represented
by a single member, the Silurian by four members, and the Devonian
by twenty. The Devonian fauna is especially rich, and represents, to-
gether with others, the typical zones of Rhynchonella cabotdes, Stringo-
cephalus burtint, and Goniatites tntumescens,so characteristic of cer-
tain faunas and horizons in other parts of the world.

The new genera described comprise P/agzofora, a tabulate coral;
Ceratophyllum and Hexagonum cyathophylloid corals; Spirzllopora, a
bryozoan; and four genera of ostracods, Antitomis, Trigonocarts, Poly-
zygaria, and Poliniella.

Interesting studies are made on the amount of crustal oscillation,
and the nature of the sediments, whether shore, near shore, off shore,
or deep sea. These observations are plotted in curves, on tables of
the geological succession for various localities. CE eB.

Morente Yo AW TAORS: CATALOGUE
OF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Agassiz, Alexander. .

A visit to the Great Barrier reef of Australia in the steamer “Croy-
don,” during April and May, 1896. (Bull. Mus. Comp. Zool., vol. 28,—
Geol. ser. vol. 3,—no. 4, pp. 95-148, 42 pls., Apr. 1808.)

*This list includes titles of articles received up to the 20th of the preceding

month, including general geology, physiography, paleontology, petrology and
mineralogy.

54 The American Geologist. July, 1898

Bain, H. F.

The Bethany limestone at Bethany, Missouri. (Am. Jour. Sci., ser.
4, vol. 5, pp. 433-439, June 1808.)
Ballou, W. H.

The serpentlike sea saurians. (Appletons’ Pop. Sci. Monthly, vol.
53, PP. 209-225, June 1898.)
Blake, W. P.

Anthracite coal in Arizona. (Am. Geol., vol. 21, pp. 345-346, June
1808.)
Claypole, E. W.

Paleolith and neolith. (Am. Geol., vol. 21, pp. 333-344, June 1808.)

Dawson, G. M.

Summary report on the operations of the Geological Survey [of
Canada] for the year 1897. (156 pp.; Ottawa, 1808.)

Dawson, J. W.

Addendum to note on Nova Scotia Carboniferous Entomostraca in
number for January, 1897. (Canadian Rec. Sci., vol. 7, p. 396, July
1897; issued Jan. 7, 1808.)

Dellenbaugh, F. S.

The causes of natural arches. (Science, new ser., vol. 7, p. 714,
May 20, 1808.)

Earle, Charles.

Relationship of the Chriacidz to the primates. (Am. Nat., vol. 32,
pp. 201-262, Apr. 1808.)

Evans, John.

Presidential address before the British A. A. S. (Canadian Rec.
Sci., vol. 7, pp. 399-426, July 1897; issued Jan. 7, 1808.)

Grabau, A. W.

Geology and paleontology of Eighteen Mile creek and the lake
shore sections of Erie county, New York. (Buffalo Soc. Nat. Sci.,
Bull., vol. 6, no. 1, xxiv and oI pp., 27 pls., 1808.)

Gresley, W. S.

Some new Carboniferous plants, and how they contributed to the
formation of coal-seams. [Abstract.]| (Quart. Jour. Geol. Soc., vol.
54, pt. 2, p. 196, May 2, 1808.)

Gresley, W. S.
Cone-in-cone: additional facts from various countries. [Ab-

stract.] (Quart. Jour. Geol. Soc., vol. 54, pt. 2, p. 196, May 2, 1808.)
NE Rte 1b.

Cuba. (Nat. Geog. Mag., vol. 9, pp. 193-242, pl. 6, May, 1808.)
Keyes, C. R.

Carboniferous formations of southwestern Iowa. (Am. Geol.,-vol.
21, pp. 346-350, June 1808.)

Authors Catalogue. 55

Kindle, E. M.

A catalogue of the fossils of Indiana, accompanied by a bibliography
of the literature relating to them. (22nd. Ann. Rept. Dept. Geol. and
Nat. Resources of Indiana, pp. 407-514, 1897.)

Lacroix, A.

Sur quelques minéraux de Boléo (Basse-Californie). (Bull. Mus.
d’Hist. Nat. Paris, année 1898, no. 1, pp. 43-44, 1808.)

Lindgren, Waldemar.

Orthoclase as a gangue mineral in a fissure vein. (Am. Jour. Sci.,
ser. 4, vol. 5, pp. 418-420, June 1808.)

LO Vintahien iss, oO:

Some illustrations of the influence of geological structure on topog-
raphy. (Jour. Franklin Inst., pp. 355-360, pls. 3-4; read Jan. 12, 1808.)
Matthew, G. F.

Studies on Cambrian faunas. (Trans. Royal Soc. Canada, 2nd ser.,
vol. 3, sec. 4, pp. 165-211, pls. 1-4, 1897.)

Merriam, J. C.

The distribution of the Neocene sea-urchins of middle California
and its bearing on the classifications of the Neocene formations. (Univ.
of Calif. Bull. Dept. Geol., vol. 2, no. 4, pp. 109-118, May 1808.)
Moses, A. J.

An introduction to the study and experimental determination of
the characters of crystals. [Continued.] (School of Mines Quarterly,
vol. 19, pp. 260-282, Apr. 18908.)

Pratt. J.-H:

Notes on North Carolina minerals. (Elisha Mitchell Sci. Soc.,
Jour., 14th year, pt. 2, pp. 61-83, 1897.)

Pome...

Mineralogical notes on anthophyllite, enstatite and beryl (emerald)
from North Carolina. (Am. Jour. Sci., ser. 4, vol. 5, pp. 420-432,
June 1808.)

{Ramsay, A. ©.]

Sketch of Andrew Crombie Ramsay. (Appletons’ Pop. Sci. Month-
ly, vol. 53, pp. 259-266, portrait, June 1808.)

Spencer, J. W.

Late formations and great changes of level in Jamaica. (Canadian
Journal, vol. 5, pp. 325-357; pls. 1-6, Apr. 1808.)

Spencer, J. W.

Resemblances between the declivities of high plateau and those
of submarine Antillean valleys. (Canadian Journal, vol. 5, pp. 359-
368, 1 map, Apr. 1808.)

Spencer, J. W.

On Mr. Frank Leverett’s “Correlation of moraines with beaches on
the border of lake Erie.” (Am. Geol., vol. 21, pp. 393-396, June 1808.)
Tarr, kh. S:

The peneplain. (Am. Geol., vol. 21, pp. 351-370, June 1808.)

56 The American Geologist. July, 1898

Turner, H. W. :

Notes on rocks and minerals from California. (Am. Jour. Sci.,
ser. 4, vol: 5, pp. 421-428, June 1808.)

Upham, Warren.

History of mining and quarrying in Minnesota. (Minn. Historical
Soc., Collections, vol. 8, pt. 3, pp. 291-302, May 10, 1808.)

Upham, Warren.

Ben Nevis, the last stronghold of the British ice-sheet. (Am.
Geol., vol. 21, pp. 375-380, June 1808.)

Van Hise, C. R.

Metamorphism of rocks and rock flowage. (Geol. Sac. Amer.,
Bull., vol. 9, pp. 269-328, pl. 19, May 19, 1808.)

Van> Horn, B.°R:

Studies on an interesting hornblende occurring in a hornblende
gabbro, from Pavone, near Ivrea, Piedmont, Italy. (Am. Geol., vol.
21, pp. 370-374, June 1808.)

Washington, H. S.

The Jerome (Kansas) meteorite. (Am. Jour. Sci., ser. 4, vol. 5,
PP. 447-454, June 1808.)

Weller, Stuart.

Description of Devonian crinoids and blastoids from Milwaukee,
Wisconsin. (Annals N. -Y. Acad. Sci:, vol. 11, no. 7, pp. 117-126, ph.
14, May 17, 1808.)

Whiteaves, J. F. —
Postscript to a “Description of a new genus and species of cysti-
deans from the Trenton limestone at Ottawa.’ (Canadian Rec. Sci.,

vol. 7, pp. 395-396, July 1897; issued Jan. 7, 1808.)
Woolman, Louis.

Fossil Fulgur perversum at Avalon, N. J. (Science, new ser., vol.
7, Pp. 751, May 27, 1808.)

CORRESPONDENCE:

RECENT SEVERE SEISMIC DISTURBANCES IN NICARAGUA. A series
of earthquakes commenced in western Nicaragua about 10:40 A. M.
on April 29th, 1808, being felt as slight tremors on the eastern side
of lake Nicaragua and increasing in their rapidity of motion and
strength of force developed as the line of greatest disturbance ex-
tended,—nearly parallel with the volcanic belt,—northwardly to the
Pacific ocean at the entrance to the gulf of Fonseca, and thence into
Salvador. The undulations continued about twice each twenty-four
hours until May 12th, 1808.

The first of the series was very much the strongest and most de-

‘*
“4

Correspondence. ° bu

structive to houses of any occurring in Nicaragua during the past half
century, developing an intensity estimated by the Rossi-Forel scale
of iv to ix, along its course from the west side of lake Managua to
the Pacific ocean, a distance on the line of its movement of about 140
miles. It passed through Managua, the capital of Nicaragua, at the
rate of about 600 millimetres per second, through Leon at about 800
mm. per second, and through the towns of Chinandega and El Viejo
at a rapidity of wave movement or progression of about goo mm. per
second.

The tile-roof covering of many houses in Managua, Leon, Chin-
andega and EI Viejo was displaced and part of the roof thrown to
the ground, and the walls of hundreds of thick-walled, one-story, adobe
houses were severely fissured, many beyond repair. Also the five-feet-
thick, carefully constructed, cement and brick walls of the cathedral
in Leon were cracked.

Several of the volcanic formed masses and cones along the line
of the greatest expression of the force of the first series, west of lake
Managua, were sufficiently disturbed to cause some greater activity
than usual in the hot mud springs near their ridges or apices and in
the boiling springs at their bases, but there has not been exit of force
enough at once through any volcano in the belt of seismic disturb-
ance to cause active volcanic eruptions.

There was no jarring motion felt, as is invariably felt when large
areas of strata fall from the inner roof,—through gases and aqueous
vapors at high tension and highly heated magma,—toward the floor
of some sub-volcanic cavern or cavernous locality. Neither were any
of the lateral movements felt-——those at an angle to the general di-
rection of the movement of the force,—that are invariably distinct and
frequent when the origin of the force is from a disturbed condition of
heated materials, gases and aqueous vapors at extreme tension be-
neath volcanic masses, as they force and fissure their way up to the
earth’s surface.

The evident origin of the development of force in this series of
earthquakes appears to have been from a contracting of the earth
from loss of heat and a consequent sliding of the strata into more
compact conditions. The waves as they developed at the earth’s sur-
face were comparatively short and high and more regular than is
usual in earthquakes from other causes. The apex of one wave arose
at the earth’s surface beneath one wing of the large one-story building
occupied by the bank in Managua and, parting the tile roof, caused the
forward part of the roof to slide from its former position a distance
of about ten feet northwardly,—along the direction that the waves of
force were moving. The other part of the roof moved southwardly
about eight feet.

The first of this series of earth disturbances was preceded for a
few seconds by a very rough grating sound, followed by a few seconds
of tremors and slight undulations, and then severe movements undu-
lated for about thirty seconds.

58 The American Geologist. July, 1898

The writer has none but improvised seismic instruments, improved
on as used for several years, and but few of them were in good working
condition when.the first severe seismic disturbance in this series passed.
The direction of the waves was northwardly and southwardly, and
the rapidity of their movement was about as herein stated.

Managua, Nicaragua, May roth, 1808. J. CRAWFORD.

THE ST. CROIX RIVER VALLEY. In the descriptions of the St.
Croix river valley brief references have been made to the preglacial and
postglacial courses of the river. The definite relation of these courses
has not been determined. Mr. Warren Upham states, that the occu1-
rence of the Upper and Lower Dalles of the St. Croix strongly sug-
gests that there, and along some contiguous extent of the present
valley, the stream is now flowing in a course which it has cut during
and since the Ice age. No closely adjacent belt, however, seems to
be probably identifiable. as a drift filled preglacial valley. In pre-
glacial times the St. Croix river was*represented by two quite inde-
pendent rivers, each tributary to the Mississippi. The greater part
of the St. Croix drainage basin including all above Taylor’s Falls
flowed south and southwestward from the mouth of the Sunrise river
to-a junction with the Mississippi somewhere between Anoka and Min-
neapolis. * * * * About a sixth part of the St. Croix basin lying
east and south of Taylor’s Falls appears to have been drained by a
stream coinciding’ nearly with the Apple river and the lower thirty
miles of the St. Croix river.*

The recent observations of Dr. C. P. Berkey, in the vicinity of the
Dalles, also indicate the postglacial character of that part of the gorge.7

The St. Croix valley varies from one-half to one mile in width and
is 168 miles long. Based upon the various physiographic features, the
valley presents three sharply defined parts designated in this paper the
Upper, Middle and Lower St. Croix.

The Upper St. Crotx. Beginning at the Upper St. Croix lake the
course of the St. Croix valley extends in a southwesterly direction for
go miles, to the northeast corner of Chisago county in Minnesota.
Thence it extends nearly south for ten miles to the Big bend at the
mouth of the Sunrise river. In this distance of 100 miles the river
descends 310 feet. The valley has an average depth of about roo feet.
From the abundant undisturbed glacial drift below the top of the early
rock gorge it is evident that the valley is essentially of preglacial
origin. During postglacial time the river has cut through the drift
in many places and is now cutting its way below the preglacial surface.
The tributaries to the Upper St. Croix show the same relations between
the preglacial and postglacial erosion. In the vicinity of Sandstone,
Minnesota, the Kettle river flows in a preglacial gorge from 100 to 150

*The St. Croix tiver before, during, and after the Ice age, p. 48, by Warren Up-
ham. Report of the Commissioner of the State Park of the Dalles, 1896. pp. 45-58.

+Geology of the St. Croix Dalles, p. 367. Amer. Geol., vol. XX, Dec. 1897.

Correspondence. 59

feet deep. The postglacial rock erosion is however small compared
with that during preglacial time.

The Middle St. Croix. Special attention is called to this part of
the valley because it seems that here the river was compelled to
abandon its preglacial course and to form the present gorge which
again unites with the preglacial valley in the Lower St. Croix. The
present course of the Middle St. Croix is 27 miles long and for reasons
appearing below is divided into three sections.

Amador Section. At the Big bend the St. Croix valley makes
an abrupt turn and extends east for four miles and then southeast
for ten miles to the mouth of Rock creek. This part of the gorge is
designated the Amador section because it forms the northeast bound-
ary of Amador township in Chisago county. The Amador section fol-
lows the course of a small preglacial stream which flowed northwest-
ward. Glacial erosion widened and deepened the preglacial valley
The main erosion features however indicate that the gorge is chiefly
of postglacial erosion.

The Dalles Section. From Rock creek the St. Croix gorge extends
south three miles to the Upper Dalles, and then southwest three miles
to the Lower Dalles and Franconia. The descriptions of this section
by Mr. Upham and Dr. Berkey show that the gorge here is essentially
of postglacial origin.

The Osceola Section. From Franconia the gorge extends south
three miles to Osceola, Wis., and then southwest four miles to a
point about one mile north of the bridge of the Minneapolis, Sault
Ste. Marie and Atlantic railway. At this point, locally known as
Prairie hollow, the river makes an abrupt bend to the east of south and
the valley suddenly becomes much wider. The several drift sheets ap-
pear in place above the rock strata on both sides of the gorge and
have every appearance of having been continuous at one time. The
bottom and sides of the gorge show no signs of glaciation. The drift
found below the top of the rock strata has fallen down from the layers
of till above. The present gorge, in part follows and cuts across nar-
row and shallow drift filled gorges whose preglacial streams flowed
westward.

The Middle St. Croix river in its distance of 27 miles falls 78
feet. The valley bears a strong contrast to that of the Upper and
Lower St. Croix, in the absence of undisturbed glacial drift, in its clear
cut features and in its youthful appearance.

The Lower St. Croix. From Prairie hollow the. St. Croix valley
extends in a southerly direction for 41 miles, to its junction with the
Mississippi valley at Prescott, Wisconsin. The Lower St. Croix valley
is entirely due to preglacial erosion. The river has nowhere succeeded
in cutting entirely through the glacial drift. The Lower St. Croix river
falls only 13 feet.

The buried gorge. In tracing the course of the St. Croix river
on a good map of this region, it is noticeable that if the Middle St.

60 Lhe American Geologist. July, 1898

Croix had continued in the direction of the lower part of the Upper
St. Croix its course would be from the Big bend through Sunrise
City, Center City and Chisago lake to Prairie hollow where it would
join the Lower St. Croix without making an abrupt bend as is now the
case. This distance is 20 miles, —seven miles shorter than its present
course. The region between the Big bend and Prairie hollow is
covered with drift averaging over 100 feet in thickness and having a
rough morainic contour over the greater part of the distance, but
the following facts seem to warrant the conclusion, that in preglacial
time the Middle St. Croix followed the course indicated above, from
the Big bend to Prairie hollow.

A depression about a mile wide and from fifty to one hundred feet
deep extends, as a continuation of the Upper St. Croix valley, about
four miles south of the Big bend. The bed of the Sunrise river in
the last two miles of its course is below the rock formations on either
side of the valley. The wells in the vicinity of Sunrise City extend
about 50 feet below the bed of the Sunrise river and in no case have
they reached rock bottom.

At Prairie hollow the rock walls of the gorge of the Lower St.
Croix continue northward one-fourth of a mile beyond the end of
the Middle St. Croix gorge. The extension of the gorge is fiiled
with drift and near its west side is a drift hill about 300 feet above the
river. Prairie hollow is the sandy prairie formed at the base of this
hill. Between the high drift hill and the eastern side of the gorge
is a depression which extends northward until it is lost in the morainic
contours of the drift, over three miles from the river. This valley is
about a mile wide and from 50 to 200 feet below the drift hills on
either side. For some distance the valley is below the top of the rock
formations in this vicinity. Well borings show that a buried preglacial
gorge extends at least three miles north of Prairie hollow. Beyond
this wells do not extend deep enough to be of assistance. Copious
springs are abundant at Prairie hollow and issue from the lower layers
of the drift which fills the preglacial gorge. The water from these
springs forms two large creeks which empty into the St. Croix. In
the present gorge below and above Prairie hollow springs are relatively
very scarce.

The only evidence of the buried gorge in the intervening territory
is that afforded indirectly by Chisago lake. This large lake has no
surface outlet. The lake rises and falls independently of the quantity
of rainfall, of the season and the condition of the surrounding region.
The subterranean outlet seems to be permanently located, for when-
ever the lake falls rapidly the water from all parts of the lake always
flows toward the same point. It is probable that the springs at Prairie
hollow are the outlet of the underground stream which discharges
the water of Chisago lake and whose course is determined by the
buried preglacial gorge.

The Middle St. Croix lies in the region occupied at various times,
separately and together, by the glaciers extending from the Keewatin

Personal and Sctentific News. 61

and Laurentide ice sheets. At the close of the Kansan stage the St.
Croix probably still followed its preglacial course. The Iowan drift
sheet effectually blocked this course. The interglacial stage between
the Iowan and Wisconsin drift was very short in this region and it
appears that the present Middle St. Croix valley is chiefly of post-
glacial origin. The Middle St. Croix valley affords an additional
case for the computation of postglacial time. The problem is highly
complicated by the number and the great variance of the factors
which must be considered. Each section of the Middle St. Croix
presents a group of factors quite different from that of the other sec-
tions. It is evident that the time interval represented by the erosion of
the present Middle St. Croix is very long. The writer is of the
opinion that 40,000 years will represent approximately the duration of
postglacial time as expressed by the history of the St. Croix valley.

The above preliminary note is intended to announce the determina-
tion of the definite relationship of the preglacial and postglacial courses
of the St. Croix river. A detailed description and discussion of the
problems involved will fcllow at a later date.

Minneapolis, April 23, 1808. A. H. ELFrMan.

PenoONAL AND SCIENTIFIC NEWS.

Pror. R. S. Tarr is spending the summer in the Rocky
Mountain region and the Pacific States, traveling extensively
to visit localities of special geological interest, in behalf of
his department in Cornell University.

CorRNELL University. An instructorship in economic
geology has been created in the geological department of
Cornell University, and Dr. Heinrich Ries of Columbia Uni-
versity has been appointed to the position.

GEOLOGICAL SociETY OF WAsHINGTON. At the meeting
of May 25th the following papers were presented :

Pitch Coal from Oregon. J.S. Diller.
Distribution and quantitative occurrence of vanadium in rocks of the
United States. W. F. Hillebrand.
ee ahe Devonian in southwestern Colorado. A.C. Spencer and G. H.
Irty.
Ao singical excursion in southern Russia. S. F. Emmons.

New York ACADEMY OF SCIENCES. Section of Geology
and Mineralogy, May 16, 1898.—Mr. Geo. F. Kunz exhibited
specimens of quartz crystals found in massive gypsum at Gal-
lineo Springs, N. Mex., and announced the discovery of a new
meteorite from Ottawa, Kas.

The first paper on the programme was by Prof. D. S.
Martin on “The Geology of Columbia, S. Ca.,and its Vicinity.”

62 The American Geologist. July, 1898

Prof. Martin described the granite and gneissic rocks of that
region and their residual products. He also commented on
thecharacter of the Potomac, Lafayette and Columbian forma-
tions which are well exposed in the railroad cuts south of the
city. The paper was discussed by Prof. Dodge and Dr. Ries.

The next paper of the evening was by Prof. J. F. Kemp
on “Some Remarks on Titaniferous Magnetites.”” The speaker
discussed the formula of ilmenite and stated that it was prob-
ably a mixture of FeO:TiO, andw Fe,O,. The amount of
titanium present in the titaniferous magnetites is very variable,
running sometimes as high as 40 per cent; in the Adirondack
ores it is 10 to 20 per cent. Magnetic methods of separation
have not yet proved successful for the elimination of the titan-
ium. Nearly all of the titaniferous magnetites show small
amounts of MnO, Cr0,, CoO; 4NiO,, VjO, andi iiaGe
The latter suggests the presence of spinel. S10, and Al,O,
have also been found, but phosphorus and sulphur are rare.
Prof. Kemp suggested that these rarer constituents might have
some influence on the metallurgical behavior of the ore. The
native and foreign occurrences of the ores were alluded to.
Discussion of the paper was by Prof. Martin, Dr. Ries and
Mr. Kunz.

HeErnricH Ries, Secretary.

GEOLOGICAL Society oF America. The tenth
summer meeting of this society will be held, in conjunction
with the American Society for the Advancement of Science,
Tuesday, August 23rd, in the lecture hall of the Boston So-
ciety of Natural History, Boston, Mass. The council will
meet Monday evening, August 22nd, and the society will be
called to order on Tuesday morning at 10:30 o'clock. The
hotel headquarters is the Copley Square. The preliminary
announcement circular of the A. A. A. S., which convenes
August 22nd, will be sent to the fellows of the Geological So-
ciety who are not members of the Association. All arrange-
ments described in this circular relating to entertainment,
transportation, etc., apply to the Geological Society and other
societies meeting in conjunction with the Association.

Pror. Epwarp W. Craypo_e_, of Buchtel College, Akron,
Ohio, has accepted the chair of science in the Polytechnic Jn-
stitute of Pasadena, California. He expects to enter upon his
new duties in September.

Pror. N. H. WINcHELL, managing editor of this jour-
nal, has been spending the past few months in Paris in petro-
graphical study and investigation. He expects to return
home the latter part of June.

Tue GeEoLocicaAL DEPARTMENT OF THE JOHNS Hop-
KINS UNIVERSITY has just closed an encampment of sev-

Personal and Scientific News. 63

eral weeks near Cumberland, Maryland, in the heart of the
Appalachian mountains. Work was suspended in Baltimore
during the period of the camp, special courses being given at
Cumberland, both by the regular corps of instructors and by
lecturers secured from the scientific bureaus in Washington.
Complete instrumental outfits employed in geological, tope-
graphical, climatological, hydrographical and agricultural in-
vestigations were installed at the camp, special lectures being
given upon their uses. In addition to practical work along
geological and topographical lines, meteorological observa-
tions were taken twice daily by the students, under the direc-
tion of an observer detailed by the United States Weather Bu-
reau, the streams were gauged and the velocity and volume of
their outflow determined, and the conditions of the soils in
their temperature and moisture contents were examined daily
under competent supervision. Among those who were pres-
ent at the camp and who aided Prof. Clark and his associates
in the work of instruction were Messrs. Bailey Willis, H. M.
Wilson, O. L. Fassig, E. G. Paul, and C. W. Dorsey, of the
Washington bureaus. It is planned to continue practical field
work in this manner in subsequent years. (Sczence.)

THE INTERNATIONAL MiniInG Concress will assemble
in Salt Lake City, Utah, at Io a. m., Wednesday, July 6th,
and continue at the pleasure of the Congress during the 7th,
8th and oth. The Congress is a permanent organization, and
is a direct outcome of the International Gold Mining Con-
vention which was held in Denver last July. In the “official
call issued for the Denver meeting the following explanation
of the objects of the Congress were given. “The objects of
the Convention are to secure such national legislation as may
be calculated to promote the business interests and develop-
ment of the resources of the mining industry in North and
South America; to bring together mining men and investors;
to increase reciprocal trade among them; to discuss such ques-
tions as are naturally suggested by its objects; to cultivate
acquaintance, fraternal feeling and hearty co- operation among
various mining, commercial and labor bodies represented ; and
especially to take under advisement the importance of the
creation, by Congress, of a department to be known as the
Department of Mines and Mining, thus securing a cabinet
officer that represents an interest which affects more than one-
third of the people of the United States.”

IMPORTANT VERTEBRATE FOSSILS FOR THE NATIONAL
MUusEvoM. Prof. O. C. Marsh has recently transmitted from
New Haven to the director of the United States Geological
Survey the fourth large installment of vertebrate fossils se-
cured in the west, in 1882- -92, under his direction as paleontol-

64 The American Geologist. July, 1898

ogist of the United States Geological Survey in charge of ver-
tebrate paleontology. The collection is packed in one hun-
dred boxes, and weighs over thirteen tons. In accordance
with law the material will be deposited in the National Mu-
seum. This collection includes twelve skulls and other re-
mains of the gigantic Ceratopsia from the Cretaceous; various
Dinocerata fossils from the Eocene; a series of rare specimens
of Lrontotherium, Elotherium, Miohippus, and other genera,
from the Miocene; a very extensive collection of A/inoceros
and other mammals from the Pliocene; as well as various in-
teresting fossils from more recent deposits.

The other important collections of vertebrate fossils se-
cured by Prof. Marsh in the west for the Geological Survey,
and previously transferred to the National Museum, may be
briefly enumerated as follows: (1) Seventy-two large boxes
of Pliocene fossils, weighing 7,500 pounds, were transferred
Dec. 31, 1886, and were stored in the Armory, Feb. 8, 1887.
The record of these boxes is on file in the office of the Geologi-
cal Survey, and the Smithsonian numbers of the boxes are
6601-6672. (2) Thirty-three large boxes (weighing 6,960
pounds) of rare vertebrate fossils, ready for exhibition, were
transferred July 17, 1891, and were placed in a case specially
prepared for them in the National Museum, before the open-
ing of the International Congress of Geologists held in Wash-
ington that year. (3) Forty-three large boxes (weighing
4, 380 pounds) of Pliocene vertebrate fossils were transferred
April 17, 1896.

These various collections with other smaller consignments
transferred to the National Museum (255 boxes in all, with a
total weight of over twenty tons) were secured under the
special direction of Prof. Marsh, as paleontologist of the
U. S. Geological Survey in charge of vertebrate paleontology,
during 1882-92. The remaining collections thus made, and
still at New Haven, will be sent to Washington as soon as
their scientific investigation now in progress is completed.

Kari LupwiG FRIDOLIN VON SANDBERGER, until recently
professor of mineralogy and geology in the University of
Wurzburg and director of the Mineralogical Institute in that
city, fied on April ido erone Sandberger is noted for his
investigations in mineralogy, in ore deposits, in petrology
and in fossil mollusca. His important work on mineral veins,

—“‘Untersuchungen tiber Erzgiinge’—was published in 1882-
85. During the last years of his life he was devoted more
particularly to mineralogy. In 1855 he was granted the
Wollaston fund by the Geological Society of engon and
in 1875 he was elected a foreign member of that society.

THE

Pore RICAN GEOLOGIST.

Vou. XX. AUGUST, 1808. No. 2

REMAINS OF A SPECIES OF BOS IN THE
QUATERNARY OF ARIZONA.

By WiLutAm P. BLAKE, Tucson, Arizona, and Mill Rock, New Haven, Ct.

The plains and valleys of Arizona in ancient Quaternary
time were the feeding ground of a species of Bos, now extinct.
This is shown by the discovery of fossil horn-cores of gigantic
size, and well preserved in the ancient cemented gold-bearing
gravels at Greaterville on the eastern side of the Santa Rita
mountains in Pima county, about thirty miles southeast of the
city of Tucson. They were exhumed by the sharp pick of one
of the placer miners, Mr. P. J. Coyne, to whom and to Mr.
Thos. Deering, of Greaterville, we are indebted for the preser-
vation of the fragments and their presentation to the museum
of the University of Arizona. From these fragments I was
able to reconstruct nearly the whole of one core, and the great-
er part of the other. The outer portions of these bones are
stained by oxide of iron, and portions of the cemented gravel
and sand adhere in places to the surface.

These horn-cores are very much larger and heavier than
any known to us amongst horned cattle, or Bos taurus of the
present time. They are nearly twice as large as. the horn-
cores of largest size of our domestic bulls. It is evident
that the animals must have had a very large skull and great
strength of neck to support and make use of such ponderous
horns.

66 The American Geologist. August, 1898

The dimensions of these fossils are as follows: Girth, or
circumference, of the largest end at or near the base where it
joined the frontal bone, 1738 inches—442 millimetres; the
greatest diameter being 6 inches—=152 milimetres in one direc-
tion, and 54 inches—140 millimetres in the other; the section
being somewhat elliptical. The length of the portion restored
is 17 inches—432 millimetres. The tip of this horn-core is
complete, but some fragments needed to make a connection
with the larger part are missing, consequently the exact orig-
inal length of the core cannot be stated, but it probably was
23 to 24 inches—650 millimetres long when complete. The
circumference of the horn-core at a point 8% inches from the
base is 132 inches346 millimetres; and 13 inches—330 mill-
imetres at 12 inches from the base. Es

The curvature is slight, and in one plane only. In this
respect and in the form and proportion these horp-cores do
not resemble the horn-cores of our American bison, B.ameri-
canus, nor do they. resemble the horn-cores of the, Asiatic
bison, a skull of which is in the museum at Tucson. Com-
pared with the familiar forms of horn-cores of our domestic
cattle these fossil cores in all respects, except size, more near-
ly approximate the form and proportions of the horn-cores of
the Hereford breed than any other. They are not like the
short horns of the Durham or the long more slender and
curved horns of the Holsteins. The form of the cores also
suggests that they projected outwards, downwards and _ for-
ward as in the Herefords rather than upwards and forwards.

While cognizant of the insufficiency of evidence presented
by horn-cores alone for the foundation of a species it is cer-
tain that in these fossil bones of the ancient gold gravels we
have evidence of the former existence at a remote period rela-
tively to human occupation of an undescribed giant boviform
animal for which for convenience of reference, at the least, I

propose the name Bos arizonica.

Fossil horn-cores comparable in size with these of Arizona,
but not certainly of the same species have been found in
Texas, in Nebraska and other localities in the United States.
So, also, in Europe where similar remains are more abund-
ant, at least more have been found, and have been described
as Bos primigenius.

Bos in the Quaternary of Arizona.—Llake. 67

The occurrences in America have been noted chiefly by
Carpenter, Harlan, Leidy and Marsh; while abroad we are
indebted for description and memoir chiefly to Cuvier,
Owen and Dawkins.

A brief resumé of this literature is desirable.

Cuvier as early as 1825* described several different speci-
mens of the remains of Bos, and gave figures and measure-
ments, cited later by Dawkins and others, and which will, also
be found in the annexed tabular statement. Cuvier observes
of the specimen, No. 1 of the table, that according to the pro-
portion of Bos taurus the skull would indicate an animal
twelve feet long and six and a half feet high at the withers. A
more perfect specimen was dug from the peat bog of Saint
Vrain in the Canton of Arpajon (No. 2 of the table). No. 5
of the table was taken from the drift of Clacton in Essex and
was described by Mr. Brown, of Stanway,t andcited py Daw-
kins. :

Dawkins in his memoir upon the “Fossil British Oxen,”
considers them under three heads or groups.{ 1. The
Great Urus, Bos urus of Julius Casar: 2. The small short-
horn, Bos longifrons of Prof. Owen: 3. The bison, Bos bison
of Pliny. He states, ‘““The large fossil ox of the Pleistocene
period termed Bos primigenius by Bojanus and Prof. Owen
differs in no respect from the Bos urus of the prehistoric and
historical period.” In Pleistocene times it wandered in vast
herds over northern, central and western Europe, and accord-
ing to Bojanus, over southern Russia and in company with
the woolly rhinoceras (R. tichorinus), and the mammoth fre-
quently fell a prey to the cave-hyena and the cave-lion. The
date of its extinction in Britain is a vexed question. In
Scania a skeleton was found in a peat bog. The animal had
been hunted by man for it had been pierced by a javelin.
Bones of this species are to be found in the lakes around the
piles of the ancient lake dwellers. Its name occurs in the writ-
ings of Pliny, Martialand Seneca. Dawkins expresses the opin-

*Ossements Fossiles t. IV, p. 150, 3d Edition.
+ Mag. Nat. Hist., n. s. 1838, p. 163.

JW. Boyd Dawkins, M. A. F. G. S., “On the Fossil British Oxen,”
Quart Jour. Geol. Soc. Lon.. X XII, 392.

68 The American Geologist. August, 1898

ion that the larger cattle of western Europe at least are the de-
scendants of Bos primigenius modified in many respects by re-
stricted range but still more by the domination of man. Owen
on the other hand thought that the tame ox of western Eu-
rope was probably derived from the already domesticated
cattle of the Roman colonists. Baron Cuvier and Prof. Bell
believed that the urus was, in part at least, the ancestor of our
domestic breeds. It was the opinion of Prof. Nilsen that the
large cattle of the Netherland and Holstein sprang from this
animal. ;

In regard to Bos longifrons Owen wrote in 1847 that it
co-existed with Megaceros in Ireland and with Megaceros,
Rhinoceros, Elephas, Hyena, etc., in England. “Remains of
this species have been found in ancient places of sepulture and
so associated with British and Roman remains as to leave little
doubt of its having survived as a species many of the mam-
mals with which it was associated in the Pleistocene period.”*

Dawkins, in his second paper,t combats this view of Owen
that B. longifrons was a Pleistocene species and asserts that it
had not yet been found to have existed before the prehistoric
age; in the bone caves and alluvia of which it is found abund-
antly, and he also asserts that it is the ancestor of the small
Highland and Welsh breeds.

The most important contribution to our knowledge of this
subject was made by Dr. Jos. Leidy,{ of Philadelphia, in his
memoir on the extinct species of the American ox, published
in volume V of the Smithsonian Contributions to Knowledge
in the year 1852. In this memoir a review and resume of the
literature of the subject in the United States may be found.
Dr. Leidy wrote that remains of extinct species of ox are
quite abundant in the post-pliocene deposits of North Amer-
ica. He notes that such remains are numerous and are in-
digenous to all the continents excepting South America and
Australia. The first distinct species of extinct American ox
was announced to the world by Mr. Rembrandt Peale. This
was based upon the specimen presented by Dr. Samuel
Brown to the museum of the Philadelphia Academy of Natural

*Quart. Jour. Geol. Soc. Lon. IV, 45.
+Ibid, X XIII, p. 184.
Phil. Mag., 1803, XV, 325, pl. VI.

Bos in the Quaternary of Arizona—Blake. 69

Science, which was found in a creek emptying into the Ohio
river. Dr. Harlan* gave it the name of Bos latifrons. A cast
of the specimen was sent to Cuvier in France. Notwithstand-
ing its size and locality Cuvier considered it to represent Bos
priscus. Leidy in July, 1852, asked the attention of the mem-
bers of the Academy to the fossil and Cuvier’s determination
of it, stating that it belongs to a species of bison and is with
very little doubt distinct from the Bison priscus and should be
called Bos latifrons. Again, in his memoir he states that Dr.
. Harlan was quite justifiable in proposing the name Bos lati-
frons for this animal. Leidy, however, in the same memoir
‘gives a description and figure of the fossil with dimensions un-
der the name of Bison latifrons.

The horn-core of this specimen was no less than 20”
inches in circumference at the base and 173 inches at ten
inches from the base. Only about one-half of the length of
this horn-core was preserved. Judging from the figure given,
one-fourth size, the core more nearly resembles the horn-core
from Arizona than any other of which descriptions have been
found, but these specimens do not appear to me to bear any
resemblance to the horn-cores of our lately existing buffalo.

At the same meeting of the Philadelphia Academy noted
Dr. Leidy exhibited a fragment of another skull and horn
which must have belonged to a smaller animal. ‘The horn-
core is relatively more conoidal and curved than in Bison
latifrons.” It was from Big Bone Lick, Ky., and probably in-
dicates a distinct species for which the name Bison antiquus
was proposed. +

Dr. Leidy, also, in his memoir directed attention to the
fossil horn-cores described by Dr. Carpenter, of which a con-
densed statement follows, and stated that they appear to be-
long to the same species described by Harlan as Bos latifrons.

Dr. William M. Carpenter, of New Orleans, described in
January, 1846,f some fossils collected by Mr. William Huff
from the banks of the Brazos river, near San Felipe, Texas.
Amongst them were remains ofan “ox,” consisting of the front-

* Harlan, Fauna Americana, p. 273.

TProc. Acad. Nat. Sci., Phil., 1852, VI, p. 117. See also Memoir
above cited.

tAmerican Jour. Science (2) I. p. 244, Art. XII, March, 1846.

70 The American Geologist. August, 1898

al bone of the skull and the greater portions of the two horn-
cores and a single tooth. These bones were found in a gray-
elly deposit and were partially coated with a cemented mass of
oxide or iron and pebbles and sand. The drawing accom-
panying the description shows the breadth of the frontal bone
and the portions of the horn-cores preserved. These horn-
cores are shown to extend outward and a little upward. The
ends of each horn-core were broken off. The right horn-core
measured two feet and the left one eighteen inches, and the
distance between the broken ends including the frontal bone
was 56 inches. The frontal bone between the horns was 14
inches in breadth, and between the external angles of the or-
bits 14% inches and between the internal angles of the orbits
11% inches.

The bones of the horns are described as nearly round (cyl-
indrical). The circumference at the base was 17 inches, and at
a distance of 18 inches from the skull the circumference was
142 inches. It was the opinion of Dr. Carpenter that the
horn-cores when perfect must have been four feet in length
each, and that with the addition of only one foot to each for
the horny parts the total breadth between the tips of the
horns must have been at least eleven feet.

In the‘Natural History of the Stateof New York,” De Kay*
enumerates four species of fossil Bovidas: Bos bombifrons
Harlan, Bos latifrons Harlan, Bos pallassi De Kay and Bos
moschatus Gadman (the musk ox). Of B. bombifrons Dr.
Leidy says this species was established by Dr. Wistar in 1814
upon a part of a skull with both horn-cones nearly entire,
found at Big Bone Lick, Kentucky. To this species Dr. Har-
lan gave the name of Bos bombifrons.+

In September, 1877, Prof. O. C. Marsh fdescribed two new
species of Bison, one B. ferox, from the lower Pliocene of Ne-
braska and the other B. alleni, also from the lower Pliocene of
Nebraska. These were represented by well preservd horn-
cores, now in the museum of Yale University, where, by the
courtesy of Prof. Marsh I have been permitted to critcally ex-
amine them.

*Zoology Part I, p. 110.
+Fauna Americana, p. 271.
ft Am. Jour. Sci, XIV, No. 81, Sept. 1877, p. 252.

ke. 71

Bos in the Quaternary of Anzona.—Bla

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72 The American Geologist. August, 1898

The horn-core of B. ferox, according to Prof. Marsh, in-
dicates an animal much larger than the existing bison, having
very powerful horns. He gives the following measurements:
Length, when complete, over 500 millimetres, radius of the
inner curve about 400 millimetres. The largest end has a
diameter of 125 millimetres and the smaller at a distance of
300 millimetres measures 77 millimetres.*

Bison alleni has its greatest and least diameters near the
base, 140 millimetres, and 110 millimetres, and at a distance of
300 millimetres toward the smaller end the diameters are 100
millimetres and 9o millimetres. Prof. Marsh also observes:
“The discovery of these two lower Pliocene species of Bison
suggests the probability that this form is a new world type,
although it has generally been credited to the other hemis-
phetes

Comparing these two fossil cores with the cores of B. ari-
zonica I find that the difference between them and the cores of
B. arizonica are greater than between each other. Both B. ferox
and B. alleni are longer in proportion to their thickness than
in B. arizonica, and the curvature is greater.

For purposes of comparison of some of the chief dimen-
sions of the B. primigenius of Europe and of the more closely
related forms of America, I have prepared the tabulated state-
ment.

THE SIGNIFICANCE OF THE FRAGMENTAL ERUP-
TIVE DEBRIS AT TAYLOR’S FALLS, MINN.f

By N. H. WrncHELL, Minneapolis, Minn.

The conglomerate at the celebrated geological locality of
Taylor’s Falls has been known since its first description by
Owen. It has been described later by Kloos, Strong, Irving
and by the writer, and recently been carefully examined by
Mr. Berkey in the course of his mapping of the region for his
thesis lately published in the American Geologist.

Dr. Owen considered the eruptive rock of later date than

In the foregoing table I have given these measurements in their
equivalents in English inches in order to facilitate direct comparisons.

+Read before the Minnesota Academy of Natural Sciences, Dec. 30th,
1897.

Eruptive Debris at Taylor's Falls, Minn.— Winchell. 73

the sandstones of the region. He had the idea that the
igneous rock had been thrust up through the horizontal strata,
and really did not entertain at all the later interpretation put
upon the structure by Kloos.. Mr. Kloos corrected Dr.
Owen’s explanation, showing conclusively that the sandstone
was deposited upon the igneous rock as a debris of erosion
after the igneous rock had cooled, and that at the bottom of
the sandstone was a conglomerate composed almost entirely
of pieces of the igneous rock. This view has been adopted
by all subsequent observers. Irving often quoted this local-
ity to show that the Keweenawan formation is unconformable
beneath the horizontal sandstones and that a profound erosion
interval separates the two formations.

At a meeting of the University Geological club, about a
year ago, this conglomerate was incidentally under discussion
in connection with a paper read by Mr. Berkey. From gen-
eral taxonomic studies of the Keweenawan and its relations
to the sandstones, published in 1895, the writer was strongly
impressed with the probability that at Taylor’s Falls were
various interesting facts yet undeveloped by former observa-
tions, one of which would probably be the separation of the
conglomerate into two conglomerates, each being at the bot-
tom of one of the parts into which the Cambrian in the north-
west is divisible, and the lower one separating the eruptives of
the IKkeweenawan (as described by Irving), into two parts.

Since that, several important and interesting discoveries
have been made, as follows, in the order in which they were
brought out:

1. The first important fact is due to microscopical exam-
ination, viz: in some thin sections examined by Mr. Berkey,
the rock from which they are derived is found to be a tuff
or grit of eruptive materials. The parts are sub-angular and
rounded, consist very largely of a highly doubly refracting
mineral like epidote, of devitrified glass and of quartz. It is
evident therefore that if this rock resulted from volcanic activ-
ity at the time of its formation, the fragments were wholly
wrought over by some detrital action.

2. On visiting the place in company with Mr. Berkey he
guided me to the spot at which this rock appears. It is at
the corner of Government and West streets, about 200 feet

74 The American Geologist. August, 1898

above the river, spreading irregularly over an area of several
rods. It shows plainly the structure of a sedimentary rock,
with oblique stratification and banding, having an observed
thickness of not more than ten feet. It lies on a coarser con-
glomerate or breccia, the general structure and dip being such
as to throw them both below a great thickness of other igne-
ous beds consisting of alternating trap and amygdaloid. The
lower or conglomeratic portion of this fragmental is made up
of large and small masses of trap, sometimes amygdaloidal and
sometimes massive, having an observed thickness between 30
and 40 feet. This might easily be mistaken for a rough con-
dition of the trap of the country, brecciated, etc., but there is
more or less of the rock (2129) above described disseminated
through it, indicating the action of oceanic and detrital forces
during its accumulation. In other words, this coarse trap-
boulder rock is of the nature of a conglomerate and lies be-
low other trap beds.

3. Seeking evidence of the thickness and the extent of
this lower conglomerate, we found a similar rock at one block
west of the public school house, where only the fine-grained
aspect is seen, and where it appears as if it had been broken
mechanically and recemented by its own debris, making a
fine-grained, nodular, hard rock, which rises three or four
feet and is exposed about 20 feet east and west. A thin sec-
tion of this rock shows essentially the same characters as that
at the corner of Government and West streets, except that it
contains more secondary silica and less epidote. In it are
also developed acicular actinolites which lie in the position
and have the form of wheat-sheaves, their extremities fraying
and spreading out. That this structure here is due to sec-
ondary growth under the action of dynamic or some other
force is evident, for these actinolite bundles lie in and pene-
trate secondary granular quartz, the fibres running frequently
from one grain into another, or even piercing several grains.

We saw no further exposure of this conglomerate until
we descended the hill southwardly to the railroad. Here
can be seen both conglomerates. The upper one rises in a
bluff where Upper Cambrian fossils are found in a dolomitic
cement embracing boulder masses of trap, and the lower one
is seen in the lower portion of the bluff and in a more limited

Eruptive Debris at Taylor's Falls, Minn.—Winchell. 75

surface exposure near the railroad at the level of the track. It
here is coarse, composed mainly of trap masses, but has the
same granular fragmental debris as a cementing material.
The trap masses vary in color and texture.

4. From these outcrops, and from the known dip and
strike of the igneous beds within which this trap-conglomerate
is embraced, it can be inferred that the strike of the lower
conglomerate is from NW. to SE. about coincident with
that of the trap. As to its thickness, while we can affirm no
more than was actually seen, we may infer from the topog-
raphy throughout which the outcrops are distributed, that
there is a greater thickness than 30 or 40 feet, and that 200
feet would be nearer the actual thickness.

This conglomerate is not known on the east side of the
river, and its dip and strike cause it to occupy only a narrow
belt extending diagonally across the southern portion of Tay-
lor’s Falls.

It is to be inferred, therefore, that at the date of the ac-
cumulation of this rock the ocean occupied the place of Tay-
lor’s Falls. That in the near vicinity were active or extinct
volcanoes, the ejections of which contributed to the sedimen-
tary accumulations. These may not have been distinctly
volcanic emissions, but may have been eruptions from fis-
sures, and the cooling lava may have spread so widely as
to form extensive sheets. These lava sheets were immedi-
ately subjected to oceanic friction and disintegration. The
glassy scoria was quickly broken and deposited as sedimen-
tary material. The occurrence of grains of aporhyolyte in
this grit shows that in these surface rocks the well known “red
rock,’ so called, of the lake Superior region, was an im-
portant ingredient, and indicates that the traps that underlie
this conglomerate at Taylor’s Falls are structurally compara-
ble with those associated with the red rock series of the north-
ern part of the state. Still it is also certain that basic elements
entered much more extensively into the accumulating con-
glomerate. The coarser and distinctly boulder-part of this
stratum is composed almost, entirely of basic material. This
is to be accounted for by the immediate proximity of the
basic traps of the formation which preceded the conglom-
erate, which are several hundred feet thick and which rise

70 The American Geologist. August, 1898

in perpendicular cliffs, as eroded by the St. Croix river, at
several points in the near vicinity, forming the celebrated
St. Croix dalles. The demolition of these older rocks by the
ocean shore would furnish a coarse bouldery conglomerate
which at a slightly later date, or at more distant or more shel-
tered points, would be buried under a finer tufaceous or gritty
stratum, the product of gentler action. This succession
seems to have formed the conglomerate and the overlying grit
here described.

The significance of this fragmental and tufaceous member
in the midst of the otherwise wholly igneous rocks of the
Keweenawan, at Taylor’s Falls becomes apparent when it is
compared with what we know of this formation further north.
About a year ago, in studying the rocks gathered at Duluth
by the geological survey, it was found that a similar grit oc-
curs there in the midst of the trap rocks, lying upon a large
series of surface flows and derived from them, at the bottom
of which is the chief gabbro mass of the region. It was also
found that two conglomerates succeed each other, in the St.
Louis valley, one containing eruptive materials and the other
not. It was also found that the record of the deep well sunk
for gas! at a few miles west from Duluth demonstrated two
eruptive series separated by a grit or quartzyte and by other
fragmental debris. At a later date it has been found that at
several places on the north shore there is a conglomerate
and quartzyte at the bottom of the upper portion of the trap
series. This conglomerate indicates in several places a pfo-
found non-conformity. It succeeded, in time, the Animikie
formation and the gabbro dikes of Pigeon point, and the apo-
rhyolytesor“red rocks” which are associated with the gabbro.
In short, about Grand Portage this break in the formation,
separating the Animikie and the gabbro with its surface flows
from the later traps is most clearly demonstrated. It has be-
come our custom to designate the gabbro and its eruptive
age Norian, and the overlying conglomerate and quartzyte,
with the basic flows which succeeded them, Keweenawan;
and we have been able to locate this conglomerate at several
points between Duluth and Grand Portage. Thus it appears
that in Minnesota, extending from Taylor’s Falls to Grand
Portage bay, the eruptive rocks which it has been customary

Eruptive Debris at Taylor's Falls, Minn.—Winchell. ay

to include in the Keweenawan are divisible into two great
series separated by a period of quiet in the eruptive activities.
During this period of comparative quiet was accumulated a
conglomerate and a quartzyte which reached the thickness
of several hundred feet.

What has now been said should be understood as referring
to a stratum which at Taylor’s Falls and elsewhere lies be-
tween two important series of trap sheets. It has no refer-
ence to the conglomerate which at Taylor’s Falls has a dol-
omitic or arenaceous cement in which are found Lingula and
Discina, indicating its Upper Cambrian age and which has
been frequently mentioned by geologists. The accident that
this later conglomerate lies directly upon the earlier, at one
or two of the most favorable exposures, has hitherto con-
fused the true relations, and has led to the belief that the
whole conglomerate belongs to the Upper Cambrian. This
was the view taken by the writer published in the geological
survey report for 1881 (10th Rep. pp. 117, 118). The differ-
ences between the matrix of the lower conglomerate and that
of the upper were pointed out, so far as they could be by field
observations, but these differences were attributed provision-
ally to a hypothetical alteration which the bottom of the con-
glomerate was presumed to have suffered. It was not till
the recent survey by Mr. Berkey that the entire separation of
the lower from the upper was established.

But this chronologic and stratigraphic separation brings
up another.difficulty, viz: may not the lower conglomerate
be of the nature of a flow breccia of the igneous rocks? This
view is that taken by Mr. Berkey in his recent paper pub-
lished in the American Geologist,* treating of the geology of
the St. Croix dalles. It must be admitted that outwardly,
when the upper surface of the conglomerate has been de-
nuded by the removal of the overlying grit and tufaceous
stratum, the rough and rounded masses that present them-
selves, making a somewhat hummocky appearance, might
be attributed to the action of a cooled upper surface of a
lava flow, brecciated and somewhat rounded by the crowding
and friction of the still moving molten portion underneath.

78 The American Geologist. August, 1898

pretation encounters are greater than in that which has been
presented, viz:

1. The ocean was present at least immediately after the
formation of the conglomerate, as evidenced by the collection
and stratification of the overlying tuff.

2. The cement of the conglomerate is of eruptive debris,
which, in several instances observed, is like the overlying tuff.
This shows that the cement was accumulating at the time of
formation of the conglomerate, and that therefore the ocean
was present, and was very likely doing the same work as
when later it spread the tuff over the conglomerate. The
immediate proximity of the older trap, which may have risen
in bold hills, will account for the coarseness of the lower por-
tion of the stratum as compared with the upper.

3. In the overlying (Upper Cambrian) conglomerate are
boulders and smaller fragments of an earlier conglomerate,
and from their nature and the proximity of this lower con-
glomerate, it is necessary to refer such fragments to this con-
glomerate.

4. General taxonomic considerations, as already stated,
point to the existence of a great fragmental stratum separat-
ing the Norian from the Keweenawan, and it is reasonable to
look for it where a great valley of erosion, like that of the St.
Croix, crosses the strike of those formations.

Still, until further examination shall show more fully the
extent of this stratum and its nature, the question of its strati-
graphic significance and importance may be held in abeyance.

THE HYPOTHESIS OF A CINCINNATI SILURIAN
ISLAND.

By ARTHUR M. MILuER, Lexington, Ky.

Dr. Keyes has recently* contended for the mythical char-
acter of the Paleozoic Ozark isle. The writer shares Keyes’
skepticism, and desires to be included among those who dis-
sent from the “old island hypothesis” as the usual method of
explaining isolated areas of older formations peeping out
from under newer upon the backs of broad dome-like uplifts.

*Science, new ser., vol. 7, pp. 588-589, Apr. 29, 1808.

Cincinnati Silurian Tsland.—Miller. 79

Our writers of geological text-books, following tradition.
have without questioning accepted this island hypothesis. It
seems to harmonize well with the theory of continental growth
from a central nucleus by progressive elevations, and is 1s
keeping with a general reluctance on the part of these and
other writers to recognize in erosion the prime factor in bring-
ing about the exposure of ancient formations. Thus Le
Conte, while admitting that some such areas may have been
uncovered by erosion, seems favorable to the “progressive ele-
vation theory,”* and again he refers directly to the existence
of a “large island in Devonian seas in the region of Cincin-
nati."+ Scott accepts the Ordovician age of the Cincinnati
arch} and the existence during Silurian and Devonian times of
islands in this region.§

Dr. Newberry, as early as 1869, when state geologist of
Ohio, attributed the exposure of Lower Silurian rocks in the
southwestern part of the state to the uncovering action of ero-
sion; but his successor, Prof. Orton, argued for the existence
of the “Silurian Island.”

Recently, also, Weller accepts without hesitation the old
view of the former existence of all these islands and has them
play an important role in the early Carboniferous seas.|| In
attempting to correlate with changes in physical geography,
the faunal changes recorded in the fossils of the Mississippian
series, a most kaleidoscopic shifting of land and water areas
(reminding us of the “catastrophic oscillations” of Woodward)
is assumed. With the meager evidence at command, it is
hazardous to attempt such paleographic restorations. ‘“‘Lau-
rentian land” and “Appalachian land,” somewhere in the re-
gions usually assigned them, there may have been; Paleozoic
sediments had to come from somewhere; but we believe the
usual ground upon which the position and outlines of these
have been deduced is open to question. Extensively denuded
surfaces of moderate geological antiquity have been mistaken
for slightly denuded surfaces of great geologic antiquity. Es-

*Elements of Geology, 4th ed., pp. 308-300, 1896.
TOp. cit. p. 341.

tAn Introduction to Geology, p. 378, 1807.
§Op. cit. pp. 386, 395,

|| Jour. Geol., vol. 6, pp. 303-314, Apr.-May, 1808.

.

80 The American Geologist. August, 1898

pecially mythical seem these alleged geologic islands and their
including seas and oceans. “Ozark and Cincinnati isles,”
“Eurasian oceans” with ‘Northwest passages,” “Osage
seas” and “Waverly gulfs” form very pretty geographic terms
and can be assigned places on a map. Like Kant’s “islands
of fancy” they may be given all the characters pertaining to
existence 7m znutellectu; but have they therefore had existence
wn re? Let us examine the evidence.

The existence of the Cincinnati island since Silurian (Upper
Silurian) times has been inferred:

First and chiefly, from the present insular exposure of Or-
dovician strata on the summit of a broad dome or anticline.
This exposure, a little over 13,009 square miles in extent and
comprised within the states of Ohio, Indiana and Kentucky,
has Cincinnati somewhat centrally placed within it. The sum-
mit of the dome, however, is in the vicinity of Lexington, and
“Lexington uplift’? would have been a preferable name to
/Cimeimmati arch.

Second, from indications of shallow water and shore con-
ditions having prevailed around this area. The alleged in-
dications are: (1) Thinning out of strata along margins of
Silurian and Devonian, with overlap; (2) presence of conglom-
erates and breccias in these same situations; (3) ripple mark-
ings in the sandstones and limestones, and (4) traces of land
vegetation.*

In regard to (1).—It is true that Devonian and Silurian
sediments are very thin along the margins of this area, but
they are also even thinner under cover of the Lower Carbonitf-
erous sediments, where these go over the lower portion of the
arch between the Kentucky and Tennessee uplifts. On the
other hand the Waverly shows no signs of thinning along
the margins. In the alleged instances of overlap (one is
known where Devonian Black shale rests directly upon Ordo-
vician limestone and shale), the proof of an interval of sub-
aerial decay between the two deposits is wanting, or at all
events is not conclusive. Moreover the drill alsc reveals these
same “‘wants” southward under cover of the Lower Carbon-
iferous sediments.

*On the presence of ripple marks, rain marks, mud cracks, etc., in
the Cincinnati rocks the reader may also consult an article by N. W.
Perry, in the American Geologist, IV., pp. 326-336, 1889. [Editor.]

—

Cincinnati Silurian [sland —Miller. SI

(2) Conglomerates and breccias.—These do exist, the for-
mer in the basal conglomerate of the Coal Measures outcrop-
ping in steep escarpments around the margins of the area
and the latter in the Clinton and Corniferous limestones
further up upon the flanks of the arch. But the conglomerate
is composed of pure crsytalline quartz pebbles, which could
not have been derived from the strata composing a Cincinnati
island, and the breccias are not contined to the Clinton and
Corniferous. Limestone pebbles have been found even in the
lowest Cincinnati limestone upon the very summit of the
present anticline.

(3)The same thing may be said of the ripple and wave
markings. They occur in Ordovician as well as in later strata
and seem to indicate that shallow seas were not infrequent
phenomena in this region during all Paleozoic time.

(4) Plant remains.—The finding in the Clinton of Ohio
of a supposed trace of land vegetation was long taken as con-
firmation of the “Silurian island hypothesis.” Since, however,
Glyptodendron eatonense has been proven to be a fragment
of Orthoceras, we have only negative evidence there. The
occurence of silicified wood in the Devonian Black shale at
different points in Kentucky is as consistent with the sargasso
sea theory of the shales deposition as shore deposition. One
would expect to find water-logged timber upon the bottoms of
sargasso seas.

Reviewing then the evidence, we cannot say indications of
shallow water and shore conditions are so much more pro-
nounced in post-Ordovician than in Ordovician strata of the
Ohio valley, as to warrant the assumption that land first ap-
peared in this region at the close of Ordovician time and has
existed continuously there ever since.

Against this view considerable positive evidence may be
cited. }

First—The present arrangement of the drainage contro-
verts it. It is difficult to understand how two such rivers as
the Ohio and Kentucky could have established themselves in
their middle and lower courses squarely across this anticline,
if the anticline were there first. But granted the antecedent
character of the rivers and the arrangement is perfectly intelli-
gible. Extending for 45 or 50 miles somewhat parallel with the

82 The American Geologist. August, 1898

axis of the anticline and a little to the eastward of it is the
“Kentucky River fault.” This fault exhibits a maximum
displacement of about 300 feet. It shows every evidence of
being contemporaneous in formation with the uplift. Only
Ordovician strata are now involved in it. Upon the theory
of the late Ordovician or early Silurian age of the Cincinnati
anticlinal island, this is all the strata that could have been in-
volved in it, and the fault must therefore have been a surface
phenomenon in Silurian times, presenting an escarpment to
the east of 300 feet. The Kentucky river strikes this fault at
Boonesboro and turns southwestward, crossing and recrossing
the line of the fault eight miles before it finally crosses to the
west at Camp Nelson. If this fault were formed antecedent
to the river and the country has suffered so little denudation
as would be indicated by the bare removal of this three hun-
dred foot escarpment, it must in all probability have presented
a considerable face even after the Kentucky river was estab-
lished, and we have the strange phenomenon of a river run-
ning up a slope of an anticline and deliberately attacking and
breaching an escarpment nine times. If the river were ante-
cedent to the fault or if the latter were not originally a marked
surface phenomenon, we can understand how the river might
adjust itself to the changing conditions as it found them, pre-
serving a record of this in its diversion to the southwest.

Second.—The indications of a vast amount of denudation
in this region renders it probable—almost certain—that the
arch was formerly covered by all the latter formations up to
and including the Carboniferous. Traces of the former pre-
sence of these formations are abundant. The Lexington
Limestone (Trenton formation of the Kentucky survey re-
ports) forms the surface rock on the summit of this dome over
1,060 square miles. It has here a thickness of 200 feet, with
the top 975 feet above the sea. It constitutes by weathering the
typical blue grass soil. ‘Tongues and outliers of the Cincinnati
(Hudson of the Kentucky survey reports) prove that this for-
mation once covered the whole Trenton blue grass area. On
the very summit of the arch a faulted outlier (a wedge-block
between two faults) preserves middle Cincinnati (Hudson)
sandstone. The fault escarpments have been entirely re-
moved.

Cincinnati Silurian Island —Miller. 83

Surrounding the Lexington limestone area comes the Cin-
cinnati blue limestone area, about 12,000 square miles in ex-
tent. The thickness of the formation is from 600 to 800 feet.
Outliers of Niagara and Corniferous limestone lie far within
the boundaries of this region. One of these, constituting
Jeptha knobs in Shelby county, Kentucky, on the western
limb of the anticline, lies approximately half way between the
internal and external boundaries. The hight of the Cornif-
erous upon the top of these knobs is between 1,200 and 1,300
feet above sea level—high enough to peep over the arch at its
highest point. This proves that the formations up to and in-
cluding the Corniferous went over the whole combined Lex-
ington and Cincinnati areas. _

A little nearer the margin of the Cincinnati area, but still
well up toward the crest of the arch, where it begins to pitch
southward under the Devonian and lower Carboniferous, is
Burdett’s knob, in Garrard county, Kentucky. This is also a
faulted outlier. It rises to a hight of 1,090 feet above tide and
preserves the remainder of the Devonian (the Black shale)
with a thin capping of Lower Carboniferous (Waverly). By
the same reasoning it seems impossible to escape the con-
clusion, that the Lower Carboniferous went over the area in
question; and if the Lower Carboniferous why not the Upper?
Outcropping all around the margins of both the Eastern and
Western coal fields is the great basal conglomerate. It rises
into great cliffs, which for the Eastern field reach an altitude of
1,400 feet where they overlook the central blue grass counties
of Kentucky. A restoration of the air lines of this formation
easily carries it over this region, and over the very summit
of the Lexington dome it one time must have gone.

We may form some idea of how high this would have
made our arch had it not been denuded. Green River knob,
in Pulaski county, Kentucky, on the summit of the arch where
is sinks to its lowest level before rising to the Tennessee
maximum, is 1,800 feet above the sea. It preserves on its
summit an outlier of Kaskaskia sandstone just beneath the
Coal Measures. As has been noted by Prof. Shaler, from the
top of this knob on any clear day may be seen the outliers of
the Eastern and Western coal fields, here some 85 miles apart.
Undoubtedly the Coal Measures once extended over southern

34 The American Geologist. August, 1898

Kentucky. The base of them, therefore, would have had an
elevation of 1,800 feet on the crest of the anticline, supposing
it were in existence. The base of the knob in Devonian Black
shale has an elevation of 1,000 feet. The formations between
this and the top of the Lexington limestone will add up about
800 feet, making 1,600 feet for the thickness of the strati-
graphic sequence between this limestone and the base of the
Coal Measures. Place this series upon the top of the denuded
blue grass dome and we have at least 2,600 feet as its restored
hight. To this must be added whatever thickness of Coal
' Measures went over.

Of course it is not unlikely denudation has been accom-
plished part passu with elevation and these extreme hights
have never been attained. It is also possible the arch in its
present condition is of recent geological development and may
have been formed subsequent to much of the denudation.

There seems to be a striking parallelism recorded in the
history of the Ozark and Cincinnati uplifts. The cycles of
erosion in each seem to have been contemporaneous, affect-
ing indeed the intervening country as well. The differences
seem to have been more in the extent of the vertical move-
ments than in the time of them. The lowest strata exposed
in the gorge of the Kentucky river, where it crosses the crest
of the uplift, is lowest Ordovician or Upper Cambrian. The
most recent elevation, as recorded by the hight above the
present channel of the old river deposits, is between 300 and
400 feet. Had the elevation been greater there seems no
reason to doubt but we might have had Algonkian strata ex-
posed, just as in the Ozark uplift.

Keyes’ views that the last uplift took place in Tertiary
times are endorsed by Marbut, Davis, Griswold and others.
Campbell, who studied the gravels, sands and clays covering
the uplands in the vicinity of the Kentucky river where it
emerges from the Eastern coal field, considers them deposits
of an upland river thrown down where its gradient changed
upon entering a base-leveled plain. He favors the Tertiary
age of these deposits and provisionally colors them as Neocene
onthe map. This would assign to late Tertiary the date of the
last upward movement in this region.

In the light then of all the evidence cited:—that afforded

Weathering of Diabase in Virginia.—Watson. 85

by the rivers in their present arrangement and past behavior;
the disposition of the formations in encircling belts skirted
by detached outliers; the positive evidence of fault scarp re-
movals;—we may conclude that denudation and not lack of
deposition of the later formations is the true explanation of
surface Ordovician in the Ohio valley; and that the “Cincin-
nati Silurian island” must hencforth take rank as a geologic
myth.

WEATHERING OF DIABASE NEAR CHATHAN,
VIRGINIA.*

By THomas L. Watson, State Geol. Survey, Atlanta, Ga.
L[ntroduction.+

While visiting Virginia during the late summer and early
fall of 1897, the writer had occasion to study and collect
specimens of the so-called Mesozoic “trap rocks,” which have
been noted in the form of sheets and dikes throughout the
most of the Atlantic border region.

Notwithstanding the rather complete knowledge of the
geological features and chemical composition of these rocks,
but few writers have touched on their disintegration and de-
composition. Wherever studied along the Atlantic border
region, their remarkable uniformity has been noted, varying
but little in mineral and chemical composition. Futhermore,
the specific gravity determinations collected from various
sources and quoted by professor James D. Danaf{ further
illustrate the striking uniformity in these rocks, the limits of
which are given as 2.94 and 3.16.

*The writer wishes to acknowledge his indebtedness to the authorities
of the United States National Museum for kindly allowing him the op-
portunity to work up the material. He is especially indebted to pro-
fessor Geo. P. Merrill, Head Curator, Dept. of Geology, in the Museum,
for so generously placing at his disposal facilities and equipment for the
prosecution of the work, as well as for the constant suggestions given
throughout. To Dr. E. C. E. Lord, I am indebted for many sugges-
tions and aid.

+The results of this investigation are based upon the methods and
principles so clearly set forth by Dr. George P. Merrill in his numerous
valuable publications on rock weathering. See Bull. G. S. A., Journal
of Geology, Treatise on ‘““Rocks, Rock-Weathering and Soils.”

+tAm. Journ. Science, 1873, (3. S.) 6, 105.

86 The American Geologist. August, 1898

Although the similarity in the above respects are very
close, the same rocks, according to locality, offer wide differ-
ences in their final products of decay. These differences are
not without their importance and significance, from an eco-
nomic as well as a scientific standpoint.

Locality. The material, from which the results given below
were obtained, was collected from a series of dikes of con-
siderable though variable widths, in the southern and central
part of Pittsylvania county, Virginia, a few miles west of the
county court house. Here the dikes break through the old
crystalline schists and gneisses of the Piedmont plateau, but
when traced for a short distance to the east and south they are
found intersecting the Triassic shales and sandstones of the
Danwvillesarea:’*

The dikes are numerous throughout the county, and good
exposures frequently occur, the best of which are seen in and
along the cuts of the Southern railway. Generally, they can
be traced with considerable accuracy over the surface by their
weathered products, mostly in the form of boulders, which,
on account of their dark color and hardness, are called
“niggerheads.” The extreme depth in decay of both dike and
country rock, renders, even in the deepest cuts, the differentia-
tion of the contact between the two extremely difficult and
often impossible.

Field Character of the Rock. Texturally, the rocks here
studied are of two kinds. The first is a very uniformly coarse
granular rock of a dark gray color, with a decided greenish
cast, and a more or less greasy lustre. In the fresh and un-
weathered hand specimen, feldspar, augite and olivine can be
detected with the unaided eye.

The second is a more homogeneous fine grained rock, of a
dark steel gray color, in which only feldspar and augite are
recognizable with the naked eye.

The final products of weathering are apparently the same
for the two rocks, and therefore, cannot be differentiated from
each other in the field. In each case, the residue is a tough
clay of a bright red color. Weathering in concentric layers,
so generally characteristic of basic eruptives, is beautifully

*For a description and extent of this area, see Correlation Papers,
Newark System. Bull. No. 85,,\U. S. G. S., p. 22.

Weathering of Diabase in Virginia.—Watson. 87

shown in this locality. Between the two extremes are noted
many stages of decay. Boulders of variable sizes and in differ-
ent stages of decay are imbedded and distributed throughout
the mass of incoherent red clay. From the beginning in
weathering to the stage where the minerals are entirely de-
composed, but still held intact, the layer of shelly structure is
well shown in the boulders.

While the color of the decay is prevailingly red, frequently
a mottled gray color is seen, and is especially noticeable in
the boulders, which have not reached the limit in decomposi-
tion, but those in which the shelly structure is still shown.

Petrograplic Features of the Rock.
TABLE NO. I.
Bulk analysis of Fresh and Disintegrated Diabase from
Chatham, Virginia.

CONSTITUENTS. I II III Vv
SA162) Gil Oe See 45-73 47.87 37-09 | 52.06
PN ANls On sis s sci as sacs ee - 13.48 14.43 13.19 13.67
PRE Gi) erst..a a) drerdeiss ¢ = o(fo was 11.60 BESS 35.60) lv 25507
iLateave: (CRYO oes ae ange eae naa 9.92 TOMAS ee Seon 8.15
Mer emesiae MEO be 5 sireronieisd-c ats 15.40 10.58 On57 5.01
SUMAN AO tarsi rach%s wal s's «ce s0 3.24 3-47 LAS Tm Biches)
eerie REGO Se crete, ota o's ante wie © 0.47 0.61 0+33 | 0.86
Neath Cote Oy 0 2 250 Sasori eistepsserevere 0.94 1.82 B283) i) 1.05

MROtAIE ces yeas 100.78 100.78 100.86 100.13
Specific pravity. 2... 22... 4... BeOMO aah sv. tates is Mann pha oars 2.953

1. Fresh olivine diabase rock.

11. Partially weathered olivine diabase rock.
111. Decomposed olivine diabase rock.

Iv. Fresh quartz diabase rock.

The fresh rock (see 1 in the above table) is a coarse
granular admixture of plagioclase feldspar, augite and olivine,
with accessory magnetite. Buiotite, chlorite and serpentine
occur as secondary minerals resulting from alteration. The
structure is characteristically ophitic, showing in a marked
degree the lath-shaped feldspars with the interstices filled

*A\l the iron is calculated as Fe,O,, which necessarily increases the
summation of the results, inasmuch as some ferrous iron is present in
the rocks.

88 The American Geologist. August, 1898

with the augites and olivines. The structure and mineral com-
position places the rock at once among the diabases, and on
account of the large amount of olivine it is definitely classed
as an olivine diabase.

The Augite occurs in large crystals with indistinct crystal
outline. Sections cut parallel to the plane of symmetry show
a very perfect cleavage. The pleochroism of some sections
is fairly strong. A—reddish-brown, p==pale greenish-yellow,
C—pblue-green. Maximum extinction angle measured against
the prismatic cleavage ¢: c=47°. Inclusions of magnetite are
common in the augite crystals. The augite was separated
from the other minerals by means of Thoulet’s heavy solution
and further by a magnet and lens to obtain particles as free
from magnetite inclusions as possible. These were analyzed
with the following results. (See 1 in table).

Table No. 2.
Analysis of Augite.

CONSTITUENTS. I Il III RATIO OF I
Silicar SiO ge snes. iwieitnie y= 48.83 48.80 4233), |) Col . 801
Noone IMINO Sa o5 00 oont 4.41 4.14 9.15 .043 .043
Prom be, Ones sicioce. aeeeae 10.01 12.36 On, |) ai

FeO 9.05
Dime CaOn ee. hee Borer |! Tomaoy 16.36 | 360 samme
Magnesia MgO........... 7 It 14.33 14.58 427 J
So@awNasO) eet csoine cree H,00.88) 0.55
Ota kes Oni vrei itatarete e 0.19
Ign. 0.25
Mota eee pee ee 100.87 99.73
Specific gravity... Bu232
——-~—-—_, ~~

ROR. OF s1Os—21el- 15
I. Olivine diabase from near Chatham, Virginia.

II. Analysis of an augite given by Hintze C. Handbuch der Mineral-
ogie, 1893, 11, p. 1107, No. CXII. Quoted from Lemberg, Zeitschr. d.
geol. Gesch. 1877, 29, 495.

Ill. Analysis of diallagic augite in hypersthene diabase, from Cul-
pepper county, Virginia. See Campbell & Brown, Bull., G.S. A., 1891,
2, P- 344-

The specific gravity of these fragments was 3.232.

* All iron calculated as Fe,O,. Assuming it all to be in the form of
FeO, the results then become 1o.o1 per cent. Fe,0,-9 per cent. of FeO -
giving a total of 99.86 per cent. for the analysis.

Weathering of Diabase in Virginta.—Watson. 89

Table No. 3.
Analysis of Feldspar.

CONSTITUENTS. I II III IV RATIO OF II
STIVGE cs Cnr ae ree 49-65 | 55.345 55-20 51.40 -Q22
AVuminay Al O22. << 24.49 | 27.299 28.60 30.98 .267
Mie Be Oe ons ais oie 5-98 0.22
lb shonen( Cri OM antes ae Boer II.02 12.284 10.64 13.40 .219
Magnesia MgO....... 4.31 0.45
RIOEEMIN ONS nso. ee one 4.55 5.072 B55 2.85 O81
rasa Ose os 2: 0.39

Total... “100.00! 100)..00 99-99 99.69

Specific gravity 2.6097 2.697 2.695.
SSS ~
foe iO ke Oo: SiO ,—t 2:73:11.
I. Olivine diabase from near Chatham, Virginia.
II. No. I calculated to an iron and magnesia free basis.
Ill. Theoretical calulation fora feldspar corresponding to Ab, An,.

IV. Analysis of feldspar in hypersthene diabase from Culpepper
county, Virginia. See Bull.G.S. A., 1891, 2, p. 343. (Campbell &
Brown.)

feldspar. A chemical analysis of the feldspar which was
separated from the other minerals in the same way as the
augite, indicates a basic plagioclase which is shown to cor-
respond to labradorite, whose albite-anorthite ratio isAb, An,
(See 3 in table). The optical properties are in accord with and
confirm the chemical analysis. Extinction angle measured
on Mx P®(o!10) gives 22°. Inclusions of magnetite and
some augite are common in the feldspar. A quantitative
separation of this minéral from the others shows that the entire
rock is made up of 32.10 per cent of feldspar.

The Olivine occurs in large crystals with fairly distinct
crystal outline. Abundant inclusions of magnetite are com-
mon. This mineral has suffered in some cases considerable
alteration into serpentine and chlorite.

No. 2 (See bulk analysis, page 87) represents the first stage
in weathering of 1, and contains the same minerals with a
further development of secondary products. The olivines in-
dicate a somewhat advanced stage of decay, shown by the iron
sesqui-oxide covering to a more or less extent the crystals,

*Calculated by difference.

August, 1898

The American Geologist.

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Weathering of Diabase in Virginia.—Watson. ol

which is a result from the breaking down of the iron in the
olivine.

No. 3 (See bulk analysis, page 87) is the completely
weathered product of No. 1, which under the microscope is
seen to be a highly ferruginous mass in which some silicate
minerals can be noticed but not identified. However, after
removing the iron stains by dilute acid, undecomposed grains
of feldspar, augite and magnetite are clearly recognizable.

No. 4 (See bulk analysis,page 87) is from an adjacent dike,
and differs somewhat from No. 1 in mineral composition. It
is a fine-grained rock with a somewhat less characteristic
ophitic structure. The essential minerals are augite and
plagioclase feldspar with considerable quartz, which is prob-
ably in quantity sufficiently large to warrant the name “quartz
diabase.”’ The accessory minerals are hornblende, magnetite,
biotite, pyrite, chlorite, serpentine and calcite.

Probably the most interesting feature of this rock petro-
graphically, is the presence of an intergrowth of quartz and
feldspar, forming a micrographic structure. The same
structure has been noticed by Dr. Adams* in some of the
Canadian diabases found to the north of the Island of
Montreal.

Mechanical Analysis of Decayed Rock.

In order, to more accurately indicate the physical con-
ditions of the decayed product, and at the same time, point
out to some degree, the physical changes in the degeneration
of this rock, a complete mechanicalf analysis has been made
yielding the results given below.

The material analyzed does not represent the final decayed
product, or soil, but is the outer decayed portion of one of
the small boulders found scattered through the mass of in-
coherent clay. The decayed portion was still coherent, fairly
firm and intact, but crumbled with considerable ease under
pressure in the hand. In color, it was a bright orange yellow
with a striking resemblance to one of the bright yellow colored

*See, Report on the Geology of a portion of the Laurentian area ly-
ing to the north of the Island of Montreal, Geol. Sur. Canada, Annl.
Rept. 1896, part J, Vol. VIII, pp. 136-137.

+I am indebted to Mr. R. S. Hosmer of the Division of Soils, U. S.
Department of Agriculture, for the analysis.

g2 The American Geologist. August, 1898

ochres. A close examination revealed a spongy mass of iron
sesqui-oxide, through which was distributed a perfect network
of white kaolinized masses of the original feldspar. To the
unaided eye the mass seemed thoroughly decomposed with-
out any trace of the original silicate minerals preserved, but
after removing the iron oxide by continued digestions with
very dilute hydrochloric acid, and the residue subsequently
examined under the microscope, considerable traces of both
undecomposed feldspar and augite were distinctly recogniz-
able, with surprisingly large quantities of magnetite. Ap-
parently, the magnetite was in as fresh a condition and in as
large quantities as in the fresh and unaltered rock.

DIAMETER IN MM. CONVENTIONAL NAMES. PER CT.*
(1) 2— .1 Fine gravel. 0.00
(2) I— .5 Coarse sand. Bio Psi
(3) -5 —- .25 Medium sand. 13.10
(4) 25 — .I Hine sand. 15.39
(5) I — .05 Very fine sand. 23.49
(6) .05 — .oI Silt. 23.98
(7) .O1 — .005 Fine silt. 4.16
(8) .005 — .OOOI Clay. 14.20

Total matter 97-53

Nos. 2, 3 and 4 show clearly to the unaided eye the com-
pound character of the mass, and when examined under the
microscope, although the iron oxide masks to a large extent
the reaction, distinct particles of the undecomposed silicate
minerals with an abundance of magnetite are to be seen. In
No. 5 the decayed products become more differentiated into
kaolin and ferrite (iron oxide), with the usual amount of
magnetite and some of the undecomposed silicate minerals still
discernible. Nos. 6 and 7 represent highly colored ferrugin-
ous masses in which a slight sprinkling of the feldspar, augite
and magnetite, can still be recognized, to a very much less
degree, however, in No. 7 than in No. 6. No. 8 is a deep buff
colored mass of fine clay showing no trace of the original
minerals whatsoever.

Chemical Analyses and their Discussion.

Below are given three tables of analyses indicating the

_ *These residues were dried over the steam-bath and weighed without
ignition,

Weathering of Diabase in Virginta.— Watson. 93

chemical nature and relationship of the same rock in as many
stages of weathering.

Recalculating the analyses in columns I and III, in each
of the three tables, on the basis of 100, and assuming one of
the constituents as a constant factor, the results given in
columns VII, VIII and IX are obtained.

Gs) Aver
Calculated Loss of Material in the Fresh and Partially
Decomposed Rock.
Fresh eee 1 Caleulated to | Calculated amounts
Olivine diabase| -,ecomposec total of 100. saved and lost.
Olivine diabase
a I II HUE, ory. Vv Vio vit.o| Vern ale Ee |
= eres
= a ad ; = Sg
iS) se) \ S Org O
= 3 ae v3 Bo. a = 29 zs
= ey Ea) At = o . O.: Ns os o wt
i D ONO n INS “4 os LA 45416 =)
MD = aS) = ASO = 2) 5 SiS Se oe
Z G | aa s @ |=238 5 ee oe ae ae
3 e |fez| & | Soe, 2 | ae | ge | 238 | &2
Pe eeeih ay each ea | 8g | ee a Wee
mo aS es Qe eo
oH tn im Ay
SiO, ....| 45-73] 12.78] 47.87|Not dét.| 45-38) 47.49] 0.99] 97.81 2.19
*AIZO, -| 13.48] 9.10) 14.43] 10.93] 13.38] 14.32] ©.00/100.00 | 0.00
Fe,O, -<| 11.60) 8.75) 11.55] 5.83] 11-51] 11.46] 0.79] 93.09 | 6.01
Cay 2-4) 9:62) 4.37), 10.45 4.49 9-84] 10.37) 0.15] 98.47 | 1:53
MgO 1--| 15.40] 8.65] 10.58} 4.28] 15.28) 10.50) 5.47] 64.19 | 35.81
Na,O. ..| 3.24/NOt dél.} 3.47/- 0.91] 3.21] 3.44] 0.00|/100.00 | 0.00
a ON eel) kOe a7 sme 0.61} 0.45} 0.47| 0.61] 0.00/100.00f| 0.00
Fae a KOLOAy OF 04) 128216 1282|-"O.93| TSI es et 0.00
Total ...|100.78) 44.59]100.78] 28.71]100.00}100.00| £7.40

31.81

The special features to be noticed in this table are: (1),
The relative amounts of material in the two rocks soluble in
dilute hydrochloric acid, which are given as 31.81 per cent for
the fresh rock, and 28.71 percent. for the partially altered; the
fresh rock yielding, therefore, the largest amount of extract.
(2),An assumption of almost double the amount of water in
column I1r as in column 1; and (3), a slight percentage loss
for the silica, iron and lime, with a rather marked loss in the
magnesia, amounting to 35.81 per cent, yielding a total loss
for the entire rock of 7.40 per cent, the alumina being the con-

* Alumina is taken as the constant factor in the above calculations.
+Gain.
Per cent.

94 The American Geologist. August, 1898

stant factor and serving as the basis of calculation. A slight
gain is noted in the potash. This may in all probability be due
to error in analysis, since the amount of this constituent found
in the rock is scarcely more than appreciable and renders
the results, therefore, somewhat unreliable.

Apparently, the change noted in the above table, in pass-
ing from the fresh to the partially altered rock, has been prin-
cipally one of hydration. A slight oxidation, however, has
taken place in the olivines, revealed under the microscope in
the slight iron stains, and restricted entirely to this mineral
wherever noticed in the slide. The only appreciable loss for
any of the constituents is in the magnesia, which has been
wholly derived from the breaking down of the olivines, and
is, presumably, the result of the leaching action of percolating
waters.

C3) oye
Calculated Loss of Material in the Partially and Wholly
Decomposed Rock.
Partially alter- Decomposed | Calculated to | Calculated amounts
ed Chwine dia-|Qlivine diabase| total of 100. saved and lost
I II Til IV Vv Wal VII VIII IX
5 =p] gid 4
iS BN) BS) § co} rf ans
Z Peer con ean p we meio pec | SS
S ZB | BaS| 2B | Bad| F a Bg) | oe ee
= re (Acs Swe E OS | Hosen
= au, ot a nA m + 3 ite) a EI
a st 1 | eles act Nee eel rate eee ae
° S| 828) 2 | Bea oe ee Be | ee ae
mere pee: bienmemeii es el es
a5 t & Mpadligi=s a ou a
—~
|
SiOg..- + 47.87\Not det.) 37-09} 12.72] 47-49 36-77] 35-57] 25.08 | 74.93
Al,O,--.-| 14.43] T0.193) 13-19] 8422) 14.32 13.08| 10:07) 20558. \7o14z
*Fe,Og.-| 11.55} 5-83] 35-69] 28.25] 11.46 35.39] 0.00/100.00 | 0.00
CaO, 4.2) Toss 440) o24t| “loto2| 010.37 ) 10240710. 23 i525 looms
MgO....| 10.58] 4.28] 0.57} 0.20] 10.50 0.56) 10.30] 1.72 | 98.28
Na,O...¢|) 63-47|O-91| 1-75] M100) 3: 445°9573) o2-07)/ 16308 paseo
K,0....2) o26n\) 0:45] 0.33) (O%20|§50.61. | 20533) 210-40) ize ao mi taza
BIO Beas: 1,62] 1.82) 11.83] 11.83) 91.81 11:73] |0.001T00.00})) 10.00
Total ...'100.78] 28.71!100.86| 62.44!100.00 100.00'f69.53
—~"
49.72
*Iron is taken as the constant factor in the above calculations.
+Gain.

Percent.

Weathering of Diabase in Virginia.— Watson. 95

Table B shows the relationship existing between the
partially and wholly decomposed rock. It is noteworthy,
that a very much larger percentage of material has been dis-
solved by dilute acid in the decomposed than in the partially
altered rock. This is clearly the result of the oxidation of
the ferrous to the ferric iron, and the retention of the oxidized
product, since the iron has remained more nearly constant
than any one of the other constituents. Of the individual con-
stituents, 74.93 per cent of the silica, 70.42 per cent of the
alumina, 98.75 per cent. of the lime, 98.28 per cent of the
magnesia, 83.70 per cent of the soda, and 82.71 per cent of
the potash have disappeared, equivalent to a loss of 69.53 per
cent for the entire rock. The calculations in tables B and C
are made on a Fe: Os constant basis. Attention is here called
to the unusually large percentage loss for the entire rock, which
is rendered excessive by the very small amounts of silica and
alumina retained. The loss in silica can be readily explained

OK Ny
Calculated Loss of Material in the Fresh and Decomposed Rock.

Fresh Decomposed | Calculated to | Caleulated amounts

Olivine diabase|Olivine diabase| Total of 100. saved and lost.

oi I II III IV V VI VIL VIII EX
SE Sra eee ie Pte le a”

= gy 85 i (eis a ie

a a | £5; 5 | So. 5) ies as

= —_ i= i) om mH o . [o} loure ep [-3)

& So eee ete aip aster) aay Rem ree |) cat |

NM = 2 re RI 8 os ios Sh ba

2 Sesh oy | eae). A z o © od BE

eS) 2 nae re oa] G a a a5 ws

= Ee eluealeran ci B 8 aa S35 ss

Pa esculenta | vocolic gs Wek Bae (Re

23 2¢ Ag eee ee
SiO,... -| 45-73} 12.78] 37.09] 12.72] 45.38] 36.77] 33.41| 26.37 | 73.64
Al,O,g...} 13-48] 9.10] 13.19} 8.22] 13.38] 13.08] 9.11] 31.81 | 68.19
*Fe.O ..| 11.60} 8.75] 35.69] 28.25] 11.51] 35.39] 0.00|/100.00 | 0.00
CaO me) 9-02) 4557) (0-41), 0,02 ©, 64) "C.4i) 9-71) 1.32.) 98.68
MgO. ...| 15.40] 8.65} 0.57|/ 0.20] 15.28] 0.56] 15.09] 1.19 | 98.81
Na,O...| 3.24/NOt del.) 1.75) 1.00] 3.21]° 1.73] 22.64) 17.54 | 82.46
Ome | O-A7|. 0.33], O20) O.471' 0233). 0.35) 22.69 |. 77.31
H,O....]* 0.94] 0.94} 11.83] 11.83} 0.93] 11. 73] 0.00/100.00t| 0.00
Total . ..|100.78) 44.59|100.86| 62.44]100.00|100.00|t70. 31 fir Gy.

*Tron is taken as the constant factor in the above calculations.
Gain.
rer cent,

96 The American Geologist. August, 1898

on the grounds that the change in the rock-has been essentially
chemical. Since no free quartz is present in the rock, the
silica has been wholly derived from the silicate minerals,
which as fast as liberated was, in great part, dissolved by the
water present and removed. The proportions of lime and
magnesia removed are about equal and are greater for these
two than for any other constituents in the rock. As is most
generally the case, an increased loss in the soda over that in
the potash is shown. The marked increase noted in the water
is what would be expected.

Table C compares the fresh with the decomposed rock.
Here, again the analyses show a total loss of 70.31 per cent,
or nearly two-thirds of the original material. The loss in-
cludes 73.64 per cent of the silica, 68.19 per cent of the alu-
mina, 98.68 per cent of the lime, 98.81 per cent of the magnesia,
82.46 per cent of the soda, and 77.31 per cent of the potash.
Such a large percentage loss for the entire rock is very un-
usual for silicious crystallines, as professor Merrill* has
pointed out from all available analyses that this loss rarely
amounts to more than 50 per cent of the total rock mass. In
the majority of cases, however, the decomposed product
analyzed, had not reached, or even closely approximated to
its limit in chemical decay, for which some allowance and
recognition must be made.

A notable example is cited by professor Merrillt in the
analyses of fresh and decomposed basalt from Crouzet, in the
Haute Loire, France, where the total loss nearly equals that
shown here, but differing essentially in an unusual loss in
the iron while the alumina remains constant, which is just
reversed for the same two constituents in the Virginia rocks.
The excessive loss in silica has been explained in the dis-
cussion under table B. Of all the constituents, the magnesia
has been removed in the largest quantity. The removal of this
constituent finds a ready.explanation in the fact that it is
mainly derived from the olivine. The weathering of olivine
in the presence of water, oxygen, and carbonic acid would
naturally result in the formation of carbonates, silica, and the

*See, Treatise on “Rocks, Rock-Weathering and Soils, 1897, p.
324.
+Ibid, p. 223.

Weathering of Diabase in Virginia—Watson. 97

sesqui-oxide of iron; the magnesium carbonate being soluble
in the carbonated waters would be carried off in solution.

The table shows that 44.59 per cent of the fresh rock and
62.44 per cent of the decomposed are soluble in dilute hydro-
chloric acid and sodium carbonate solutions. Furthermore,
that in passing from the fresh rock to the decomposed the total
amount of water has very greatly increased.

The conditions, under which the degeneration of thie
rock here studied has taken place, indicate, that they have been
essentially of the nature of chemical decomposition rather
than of mechanical disintegration. Evidently, then we have
a rock whose decomposition is practically complete accom-
panied by a total loss of nearly two-thirds of the original
material. While this loss, so far as data are available, is un-
usually large, it is probably what would naturally follow under
conditions where the process is approximately complete and
the forces involved are mainly chemical rather than mechani-
eal. Clearly, the increased loss in magnesia indicates that
the olivines were the first of the rock constituents to yield to
the agencies of decay, the feldspar and augite proving the
most refractory. This order has been shown by microscopic
study, which finds confirmation in the chemical analyses.

With the above exceptions, the results and conclusions in
general, closely agree with those reached by others in such
cases. They point conclusively to the changes that have taken
place in the decomposition of the rock being principally those
of hydration and oxidation.

Order of Decay in the Component Minerals.

A microscopic study of the thin sections representing
several sticcessive stages in the rock decay, determined the
least and most refractory of the minerals under the meteoric
conditions for that locality.

However, tests were made on several portions of the fresh
and decayed material with reference to the order of the
solubility of the minerals in dilute acid. Also, to ascertain if
possible what relation, if any, existed between the weathering
under the natural conditions and that of solution.

The material was partially powdered and passed through
a 40 mesh sieve, in order to secure grains of a uniform size,

98 The American Geologist. August, 1898

though precaution was taken not to reduce the grains fine
enough to destroy their individuality any more than was pos-
sible. Portions were then digested on a water-bath, kept at a
strong ebulition, in a covered dish, for several weeks with
dilute hydrochloric acid, fresh quantities of which were added
from time to time. A microscopic examination was made
each time, after pouring off the extract, with the following
results——None of the mineral grains could be recognized as
olivine after the digestion. This would indicate that the olivine
had been dissolved and was the first mineral to yield to solu-
tion, and therefore the most susceptible. A thin section of
the rock showed that the olivine had been altered in an ap-
preciable degree to serpentine. Of those minerals recognized
under the microscope, the feldspar proved the least resistant.
. Particles of various sizes were noted, but generally only small
fragments of the original grains were left, which evidently
suggested that a part of the fragments of the feldspar had been
entirely broken down by solution. Usually the largest grains
were either partially or wholly covered with an opaque
material, taken to be kaolin, which would probably account to
some extent for their more refractory nature. While, on the
whole, the augite grains were appreciably reduced and showed
marked etching from solution, it proved the most refractory
of the essential minerals in the rock. So far as could be seen
the magnetite underwent but little change from solution.

Apparently, the above results are in full accord with the
mineral decomposition as shown under the natural conditions.
That is to say, the decay, in this special case, seemingly fol-
lows, very closely, the order of solution of the various
minerals.

The extent to which investigation in this direction has
been carried, probably shows the opposite order of mineral
decay in rock weathering to be of a more frequent occurrence
and therefore more general.

The ferro-magnesian silicates, and especially those com-
posed principally of the protoxides of the basic elements, such
as iron and magnesia, are more susceptible to decomposition -
than the feldspars, owing to the readiness with which they
are oxidized. Professor Merrill* states, that, ““The evidence

*See, “Rocks, Rock-Weathering and Soils,” 1897, p. 234

Weathering of Diabase in Virginta.—Watson. 99

bearing upon the relative durability of the various minerals
constituting rocks is, however, quite conflicting and unsatis-
factory.” . The results are probably, to a very large degree,
controlled by local conditions. Cases are cited by professors
Dana* and Merrilltamong basic rocks, where the feldspar was
the first mineral to yield to the atmospheric agencies.

Amounts of Material Soluble in Different Strengths of Hydrochloric
Acid.

As the heading of table signifies, the results herein
tabulated were obtained under as nearly the same conditions
as was possible, varying only the strength of acid. In each
case, approximately .5 of a gramme of the finely powdered
rock was accurately weighed off and used. These weighed
portions were digested in closely covered dishes with too C. C.
each of the various strength acids, for three hours on a water-
bath, brought to a strong ebulition and maintained through-
out the digestion. They were then filtered and the filtrates
subsequently evaporated to complete dryness in order that any
soluble silica might be rendered insoluble.

The acids used were carefully and accurately prepared from
hydrochloric acid of 1.20 specific gravity. The strength 1:1
by volume, meaning 50 C. C. of 1.20 specific gravity acid to
50 C. C. of distilled water—at ordinary temperature. The
normal, half normal, and quarter normal strengths, meaning
the whole, half and quarter molecular weight respectively of
1.20 specific gravity acid dissolved in one litre each of dis-
tilled water.

While the results, probably, have not been carried far
enough to warrant any very definite statement, they are, I
believe, highly suggestive and of some interest. No limit was
reached where the extracts remained approximately the same
for any two acids of nearly equal but varying strengths, but
the difference in each case is appreciable and quite noticeable.
It would be expected that where all other elements of con-
dition remained fixed and constant, that a point would be
reached where a maximum extract would be found, corres-
ponding to a certain strength acid.

*Rep’t. Wilkes Exploring Expedition, Geology, 378.
Bulletin U. S. G. S., No. 110, 1894.

100 The American Geologist. August, 1893

Loughridge* has shown this to be true in the case of soils,
and further pointed out a limit as to time, with reference to
the amount of soluble material removed by digestion.

Turning now to the table, we find of the constituents de-
termined, the alumina shows the greatest variation, with
probably the lime next, although, in most cases, the iron in-
dicates equally as great a variation.

The magnesia remains fairly constant for the same rock
in I and II, while IV showsa wide variation, except when
the maximum and minimum strength acids are compared.

Undoubtedly, some importance can be attached to the
presence of the large amount of olivine in the first two rocks,
and the readiness with which this mineral is dissolved by
hydrochloric acid. It seems fair to assume, therefore, that
the uniformity in the magnesia determinations can be ac-
counted for in part on this basis. This is apparently more
fully warranted when we notice the variation in this consti-
tuent to be equal to that of any other in rock IV, which is an
olivine free rock.

Each residue was carefully examined under the micro-
scope, after filtering off the extract, and an abundance of un-
decomposed silicate minerals was noticed in all, generally in
a highly etched condition. With the exception of the strong-
est acid used (1:1), the residues from the remaining acids in-
dicated as great an abundance of magnetite as in an untreated
portion of the same rock, which so far as could be detected
showed apparently no etching. It follows then that the above
acids are not sufficiently strong to dissolve this mineral, or
else it is not a straight magnetite (Fe: Os). A qualitative
analysis, however, confirms that it is a pure magnetite, con-
taining no titanium, magnesium, chromium or other elements
sometimes found replacing a part of the iron. These results
were further confirmed by powdering a crystal of pure Fe: Os
and digesting for a short time on the water-bath with acids
of various dilutions. It was found that as the strength of the
acid was increased the solubility of the magnetite also in-
creased, and when treated with concentrated hydrochloric
acid only a few minutes were required to completely dissolve
the mineral. While some of the mineral was dissolved, enough

*Loughridge, R. H., Am. Journ. Sci., 1874, (3. S.) 7, 21.

Fjords and Submerged Valleys of Europe —Upham. ot

remained undissolved to'show that hydrochloric acid of the
usual dilution is quite insufficient to completely dissolve the
magnetite.

Attention is further called to the large percentage of
alumina extracted by the various acids in the above table. In-
vestigation by others has shown that the amount of this con-
stituent extracted by a quarter normal solution of hydro-
chloric acid rarely exceeds 4.75 per cent. The explanation
in this case would seem to be in the variety of the feldspar
since this is the principal source of the alumina in the rock.
Both its chemical nature and optical properties place it as a
labradorite and belonging therefore to the basic plagioclases,
the solubility of which increases as the anorthite molecule is
increased.

{European and American Glacial Geology compared. VII.]
FJORDS AND SUBMERGED VALLEYS OF EUROPE.
By WARREN UPHAM, St. Paul. Minn.

Hundreds of fjords, ranging from a few miles to a hundred
miles in length, indent the hilly and mountainous plateau of
Norway. The seashore of the country, measuring about 1,700
miles in its general outline, is multiplied sixfold by its intri-
cate windings and by these long, narrow, and often branching
fjords. Along the outer shore, also, thousands of islands,
islets, and skerries of bare rock, have been left during pro-
longed subaerial erosion, being divided by channels which are
the ramifying continuations of the fjords that penetrate the
mainland. ‘The greater parts of the steamer routes on all the
west coast of Norway, from Stavanger to the North cape, are
sheltered from the open sea by island breakwaters which form
almost continuously the outer coast line.

Beyond this present coast, the submerged border of the
continental plateau reaches to a distance that varies from 10
to 125 miles. It is widest for two degrees next south of the
Arctic circle, and narrowest near lat. 69° 20’, off the north end
of Ando. The depth of the submerged continental border is
3c0 to 600 feet along a distance of 200 miles upon the extensive
bank which adjoins the mountain range of the Lofoten islands;

102 The American Geologist. August, 1898

but elsewhere the depth of this margin of a former land sur-
face is from goo to 1,200 feet. Through all its course the old
land border is limited by the submarine contour of 200 fath-
oms, from which a much steeper descent, precipitously steep
west and north of the Lofotens, sinks rapidly to oceanic
depths of 3,000 to 9,000 feet.

’ The shallow, submerged plain, having a mean width of 60
to 75 miles, was doubtless built up as low coast lands, while
this part of Europe stood 600 to 1,200 feet higher than now.
Its material was supplied from the waste of the higher land
through its erosion by rain and streams, sculpturing the ele-
vated peninsular plateau into mountain peaks and ridges, with
cafion valleys which have since become the sea-filled fjords.
The time of this highland erosion and coastal deposition may
have comprised the whole of the Mesozoic and Tertiary eras,
which are not represented here by any formations above the
sea level. It was separated from the present time, however,
as I believe, by a great epeirogenic movement of much higher
uplift of northern Europe, preceding the Glacial period and
causing its vast snow and ice accumulation, and by an ensu-
ing depression, which in its turn caused the relatively sudden
termination of that period by the melting of its ice-sheet.

In my journey a year ago from Helsingborg, Goteborg, and
lake Wenern, to Christiania, lake Mjosen, and Trondhjem,
and thence east and south to Stockholm and to Goteborg
again, only a glimpse of this great peninsula was obtained,
which, happily, I am enabled to supplement somewhat fully
through the aid of a valuable series of maps and coastal charts
kindly supplied me by Dr. Hans Reusch, the director of the
Geological Survey of Norway, and through other maps and
brochures received from Dr. Andrew M. Hansen, of Chris-
tiania, Prof. Otto Torell, director of the Geological Survey
of Sweden, and Dr. Edvard Erdmann and Baron Gerard De
Geer of the same survey. The Norwegian maps, showing alti-
tudes of the land and depths of the sea, both offshore and in
the fjords, have been of especial service in this paper, which
will consider the origin of the fjords in its bearing on the
probable cause of the Ice age through high continental eleva-
tion. For this purpose the following table presents notes of
some of these very remarkable valleys in their order from
south to north:

Fjords and Submerged Valleys of Europe—Upham. 103

. FJORDS OF NORWAY.

Length. Width. Maximum
Miles* Miles. depth. Feet.*

PMMA OLO) 5. 3 cle)d cave clacce sc sessese cede 50 1-8 1,380
Sey eRMOrUee tacks seis Megcdeecs as ee. as 30 0.5-5 2,350
LIGETI CG Ube a oe elena Pan ea ar 23 0.3-1.2 1,414

This tributary of the Stavanger fjord is inclosed by precipitous
cliffs 2,000 to 3,300 feet high.
Hardanger fjord, with the Bommel and Sor

MA ao toc tte a vos F alase ie ticis a cje Aas 100 0.5-4 2,195
Sogne fjord, with Lyster fjord ............ 112 I-4 4,080

The depth of the Sogne fjord, the longest in Norway, at the mouth
of Aurlands fjord, 75 miles from the outer coast, is 3,875 feet; and
this southern branch fjord, 16 miles long and about one mile wide, lying
between precipitous rock walls 3,000 to 4,000 feet high, has a depth
of 1,535 feet at the mouth of its magnificent tributary, the Nzr6 fjord,
which is about ten miles long and varies in width from a tenth to three-
fifths of a mile.

Monch OLGy rope sists sitte v ai'sseonaie = sw Soodtere eves 60 I-2 2,100
Stor fjord, with Geiranger, Sunelvs, and

PMN OR CMe et et atolct sia aicitic navn"! 5 died sa, vous eay0 60 0.5-3 1,405
Momdeon onsdals fjord ..........06s ses 35 I-5 1,440
Trondhjem fjord, with Beitstad fjord.... 90 0.7-8.0 1,895
nanenenjonrd. lat, 66 degrees :2..25....--< 55 I-3 1,450
West fjord, with Ofoten fjord ..........:.. 80 2-20 2,090
Alten fjord, with Stjern sound, to the outer

oe SAU a cies doicrd su 2 sins nix « 9 ais 6160) '0\910 55 2-10 1,375
Nica CL ETFO o ayeyarcletelcia’s)<-cyerel wichelelsisrsievass «ee 35 3-12 1,340

It is noteworthy that several of these fjords are of nearly
the same depth, from 1,380 to 1,495 feet, which, I think, repre-
sents approximately the maximum Pliocene elevation of the
country, during the later part of the time of formation of the
submerged coastal plain. Numerous channels in that plain,
which probably were its Pliocene river valleys carrying the
drainage of the central highlands to the coast of that time,
sink 100 to 500 feet below the adjoining sea bed. Sound-
ings to the bottom of these submarine valleys range from 500
to 1,420 feet, agreeing well with this estimate of 1,400 or 1,500
feet as the maximum amount of the Late Tertiary elevation.
These channels are situated far offshore, with no prominent
higher tracts so near as to possibly account for exceptionally

«Distances are given in English statute miles, and depths in English
feet. The Norwegian foot equals 1.0294 of English measure.

%

104 The American Geologist. August, 1898

powerful glacial erosion along their courses, such as may be
supposed to have greatly deepened some of the fjords.

One of the most interesting of the preglacial river valleys
now submerged extends thirty miles out in a nearly straight
west-northwest course, from the mouth of the Sule fjord,
which is the seaward continuation, between islands, of the Stor
fjord. This is a well defined channel in the sea bed, having
a width of one and a half to two miles. Its depth is mostly
850 to 1,000 feet, with depths of only 200 feet, or less, to 500
feet, on each side. It is called, on the chart, Bredsundsdybet
(the “Depth in the Broad sound”). Before reaching the edge
of the submarine continental slope, this channel gradually
shoals out within five miles and is lost, the depth of the sea
there being only about 300 feet. From the central part of its
course, however, a wider submarine channel of 500 to 885 feet
depth, runs southward and thence westward to the deeper sea,
indicating the probable course by which the preglacial valleys
of the Nord and Stor fjords discharged their united waters.

Besides the preglacial stream and sea deposits which
mainly built up the coastal plain, it is certain that much glacial
drift is spread over it, everywhere partially filling the old
river courses and probably in many places covering them en-
tirely. The drift deposition appears to have been deepest,
however, just along or close outside the present shore, in the
meandering channels of the coastal belt of islands, and at the
mouths of the fjords, which always attain their greatest depth
at some distance inland. Although some of the fjords ex-
ceed 2,000 feet in depth, and one is 4,080 feet deep, the mouths
of them all are comparatively shallow, being usually from 100
to 300 or 500 feet deep. Whether we ascribe the excavation of
the deeper fjords chiefly to preglacial streams or chiefly (in
its latest and deepest part) to glacial erosion, we shall in either
case be led to the conclusion that their mouths and the ad-
joining sea must be much built up with glacial deposits.

The British Isles, as shown by the studies of Prof. James
Geikie, Prof. Edward Hull, and others, stand on a broad, shal-
lowly submerged continental platform, which is terminated
westward, at the submarine contours of 100 to 200 fathoms
(600 to 1,200 feet), by steeply descending slopes to the abyssal
ocean, Narrow valleys from 100 to 400 feet deep below the con-

Fjords and Submerged Valleys of Europe—Upham. 105

tiguous sea bed, with their bottoms 570 to 1,194 feet below the
present sea level, are ascertained by soundings in various parts
of the British submarine platform. The most notable of these
valleys are the “Hurd Deep,” four to five miles across and
extending 70 miles westward in the English channel, south of
the limits of glaciation, and a remarkable valley extending 30
miles with a width of one and a half to two miles and depth of ©
300 to 400 feet below the bed of the deep and broad passage
that separates Scotland and Ireland. The position and nar-
rowness of the second of these submarine valleys, as of those
noted off the coast of Norway, preclude its reference to glacial
erosion. Its maximum soundings, 1,194 feet, indicate for this
region during some part of the Pliocene period, while the
alluvial and marine deposition of the British platform was
being completed, an elevation probably 1,200 to 1,500 feet
higher than now, or nearly like that estimated for Norway dur-
ing the same period.

Farther south, where no confusing conditions of glacial
erosion and deposition can impart any uncertainty to our in-
terpretation of contours of the submerged continental border,
we have in the southeast part of the Bay of Biscay a most
significant ancient river valley in the sea bed, traced about 120
miles westward from Cap Breton, France, nearly parallel with
the northeast shore of Spain. Coast charts kindly obtained for
me in Paris by Prof. N. H. Winchell supply the following
notes of this wonderful submerged river course, which is
called the “Fosse de Cap Breton.” It begins a quarter of a
mile offshore about one mile north of Cap Breton village,
having there a depth of 125 feet; within the next quarter of a
mile it deepens to 230 feet, with a depth of only 50 or 60 feet
close north and south; and a mile offshore the old valley has a
sounding of 350 feet, but only a depth of 100 feet is found
within a fifth of a mile both north and south. Along the next
five miles the submarine valley sinks to a depth of 1,090 feet;
but it includes one sounding of 1,220 feet ata distance of
three miles from the shore. Its width at this exceptionally
deep spot is about one mile, the sea bed on each side having
the depth of 130 to 150 feet. At the distance of six miles the
valley is one and a half miles wide, with soundings of 260 feet
to the general continental slope, beneath which the old river

100 The American Geologist. August, 1898

had cut down about 750 feet. Twenty-five miles from the
Cap Breton shore, the valley has the profound depth of 3,670
feet, and has widened to about ten miles between the tops of
its sides, which, like the general sea bed of large expanses
north and south, have the depth of about 460 feet. At forty
miles the valley has a sounding of 6,135 feet. At eighty miles
its depth is 7,140 feet. Within seven miles farther it more
rapidly deepens to 8,700 feet, with 650 and 1,175 feet less
depth two miles away respectively on its south and north
sides. Thence along a distance of thirty miles it holds a
somewhat uniform depth from 8,700 to 9,000 feet, this being
apparently the measure of the maximum continental uplift
when the old river eroded its valley. Thirty miles northward
from where the valley ceases to be recognizable, the Bay of
Biscay is 10,830 feet deep, and twenty miles farther north its
depth is 12,600 feet.

The present representative of the old river is the Adour,
which has its mouth ten miles south of the “Fosse de Cap
Breton;”’ but formerly it was turned northward by dunes, so
that its mouth at the end of the fourteenth century is said to
have been about ten miles north of Cap Breton.

This submerged Adour valley is the most accurately
known, by special hydrographic surveys, among several others
on the border of the continental plateau in the Bay of Biscay
and along the western coast of Spain and Portugal, which
together demonstrate for southwestern Europe an uplift of
late geological date to a vertical amount ranging probably
from 5,000 to 9,000 feet. The border of the continent, built
out by sedimentation during the Tertiary era to the submarine
contours of 600 to 1,200 feet, with steep descent thence into
the deep ocean, has mainly on these coasts a width of 10 to 30
c1 40 miles. Subsequent to the formation of this continental
shelf bordering the hilly and mountainous present land area,
western Europe and western Africa experienced an epeirogenic
uplift which at its maximum, as known by the submerged
Adour and Congo valleys, lifted these great land areas from
one mile to nearly two miles vertically above their present
altitude.*

*From the mouth of the river Congo its submerged valley is traced
by J. Y. Buchanan to a distance of about 100 miles and a depth ex-
ceeding 6,000 feet; and another submarine valley of great depth, called

Fjords and Submerged Valleys of Europe-—Upham. 107

Inquiring by what means the fjords of Norway received
their excavations to depths that now are 2,000 to 4,000 feet
beneath the sea level, I believe that its explanation is found
chiefly in river erosion permitted by epeirogenic movements.
The early Pleistocene uplift of western Africa and the Spanish
peninsula probably extended to the British Isles and Scandi-
navia, giving in these northern latitudes snowfall through all
the year, by which the European ice-sheet was amassed. Dur-
ing the progress of the uplift, to its culmination in the Ice
age, perhaps 100,000 years elapsed, affording sufficient time
for the rivers to cut the submarine valleys and the deep fjords.
For a long period northern Europe was enveloped by snow
and ice, which attained great thickness and weight, averaging
probably a half mile in depth on an area of about 2,000,000
square miles. Under its weight the land sank to a maximum
in the Scandinavian peninsula of about 1,000 feet, as deter-
mined by Baron De Geer, below its present hight; and the
ice sheet, with the restoration of low altitude and temperate
climate on its border, was rapidly melted away, the unbur-
dened land meanwhile rising from its subsidence. The epeiro-
genic deformation was doubtless greatest along the conti-
nental borders, and it may have permitted the Scandinavian
high plateau to rise and sink and again rise, while the conti-
nental margin now beneath the sea underwent only a small
part of the amount of oscillation that the fjords indicate for the
interior of the country.

It seems needful further to add only a few words that
attention may be directed also to the well known studies by
Lindenkohl, Spencer, and others, of hydrographic surveys on
the Atlantic coast of Canada and the United States and in the
West Indies, and of Davidson on the Pacific coast of the
United States and of Lower California, which show for North
America an early Pleistocene uplift of similar altitude as on
the east side of the Atlantic in the Old World. The ie

the “Bottomless Pit,’ is found by soundings near lat. 5° N. on the
African coast (Scottish Geog. Mag., III, 217-238, with charts and
submarine profiles, May, 1887; Proc. ACAD AG S., XLI (1892), 171-173).
The submerged valleys of the French, Spanish, and Portuguese coasts
have been recently studied by Prof. Edward Hull, who writes that
“the great upliit, presumably reaching its maximum at the commence-
ment of the Glacial epoch, is conclusive’ (Nature, LVII, 582, April 21,
1898; LVIII, 51, May 19, 1898).

108 Lhe American Geologist. August, 1898
of the glaciated northern part of our continent, of the Arctic
archipelago, and of Greenland, having a maximum depth of
more than 3,000 feet in the Franz Josef fjord of eastern Green-
land, agree with the Norwegian fjords in pointing’ to epeiro-
genic causes of the Ice age and of its sudden end.

REMARKS ON THE CLASSIFICATION OF
THE MISSISSIPPIAN SERIES.

By CHARLES R. Keys, Des Moines, Lowa.

When, a few months ago, occasion was taken in this jour-
nal to give some of the reasons why the name Augusta, as a
title for one of the subdivisions of the Mississippian series, had
been used in the reports of the Lowa and the Missouri geologi-
cal surveys, it was not anticipated that the subject would have
to be again referred to so soon. However, Mr. Weller, in re-
cent issues of both this magazine and the Journal of Geology,
takes exception to the facts presented. He would have us be-
lieve that grievous errors had been made in adopting any other
title than Osage, and in not following the classification of the
Mississippian rocks proposed by his former instructor in geol-
ogy. It is unnecessary to reiterate the facts already given.* It
does, however, seem desirable to call attention briefly to some
other phases of the subject, that should have been, perhaps,
included in the former article. Significantly enough Mr. Wel-
ler makes not the slightest allusion to them.

As to whether Augusta or Osage should be the title re-
tained for one of the members of the Mississippian series is a
matter of small consequence. One name is as good as another
for a formation, provided it has some significance and it ac-
cords with the laws of usage in the science in which it occurs.
So far as the two names mentioned are concerned Osage is,
I think, much the prettier. Under ordinary circumstances it
would be, according to my own ideas, preferable. It is, indeed
unfortunate that there should exist conditions in science com-
pelling us to become familiar with names for which we have no
liking.

In his last paper, arguing for the adoption of Osage in place
of Augusta, Mr. Weller, as a lawyer, has no doubt entered the

*This journal, vol. XXI, p. 228, 1808.

Classification of the Mississippian Series.—Keyes. 109

very best plea possible for a lame case. Were this feature
not so conspicuous throughout his presentation one would be
almost forced to the conclusion that our critic had not read
very carefully the literature of the subject. For example, in
the leading quotation that he makes he could have easily
quoted one clause farther, giving to my sentence a mean-
ing directly opposite to the one that, as it now stands, must be
inferred.

Now, as a matter of fact, Mr. Weller has avoided entirely
the vital factors determining the choice of one of the two terms
under consideration. When the “impartial judges’ come to
examine the literature (if they ever do) they will certainly have
to search his last remarks long and vainly for a single point
wherein he has touched upon the essential features of the
paper he criticizes. One cannot help thinking that if the au-
thor of “Osage vs. Augusta” had devoted but one tenth of
the time in examining the other side of the question, that he
has manifestly done in viewing it from his own standpoint he
would have come to very different conclusions.

When “Use of the Term Augusta in Geology” was con-
sidered only a few of the stratigraphical and paleontological
reasons for not using Osage were presented. The name Os-
age, as it appears in geological literature, also has a nominal
history. It has been applied repeatedly to geological forma-
tions long before it was thought of in connection with the
Burlington and Keokuk limestones. The name is widely
known in both Missouri and Kansas, referring to certain coals
and their accompanying shales, in fact to several distinct sets
of beds in both the Des Moines and Missourian series. One
of these will doubtless stand as a useful geological term.
Moreover, the formations to which Saunders and also Hay
have given the name in question have been, I believe, as well
defined as most of the other geological formations now recog-
nized in the region. King, Owen and Johnson have also used
the name Osage in no uncertain sense in the same region; and
it is not improbable that one of these meanings will have to be
retained, if we consider at all the law of priority, and desire
to do justice to workers no less conscientious and scientific in
their day than we find in ours.

Personally I care nothing whatever about the title Augus-

110 The American Geologist. August, 1898

ta, merely because of the fact that I happened to suggest it.
I have always found it the best to use terms already in use if
it is possible to do so. When an author proposes, defines and
publishes a name in science it ceases to be his property and
subject to his control. He cannot withdraw it or replace it.
His insistence upon its adoption avails nothing. The workers
in his branch determine its usefulness or its uselessness in ac-
cordance with the laws of nomenclature that best subserve the
science. Judgment passed upon titles must have as its founda-
tion the avoidance of confusion. Were it possible, | would
be perfectly satisfied to substitute for Augusta the name
Dewey, Hobson, or even Yankee Doodle, if those who are to
come in contact with the formation would propose it and agree
to its usage.

In view of the fact that the name Osage is almost certainly
to be retained for another member, having the same taxono-
mic rank, of the Carboniferous in the same region, and in view
of the many other objections regarding the character of the
subdivision it is proposed to refer to, as enumerated in a pre-
vious article, | am not yet convinced of the advisability, or of
the desirability of using the name for any part of the Missis-
sippian series.

Mr. Weller is a paleontologist. He is well acquainted with
the code of rules governing the nomenclature of fossils. He
knows full well that essentially the same rules exist in other
branches of science. Why then should he expect to enter the
field of geology and not expect to follow the same laws, at
least in spirit, as nearly as possible.

In his other article on the Mississippian series, Mr. Weller
dwells upon the “higher purposes of major classifications as an
expression of the vital features of the history of the region,”
whatever that may be. He speaks also of the applicability, in
a geologic province, of an epoch name “as a stratigraphic
name to all strata deposited during that epoch.’ In the very
next sentence he says: “It may not always be possible to draw
a sharp and fixed line in the stratigraphic series between two
succeeding epochs so that every where throughout the geo-
logic province the exact limits of the historical epochs may be
pointed out.”

There never was a clearer presentation of the utter incon-

Classification of the Mississippian Series.—Keyes. III

gruity between an hypothesis of geological correlation and
classification and the practical scheme as actually developed
in the field. Has it not been this very lack of effort to draw
close lines that has enabled the paleontologist to fancifully ex-
tend the geological formations around the world, like the con-
centric layers of an onion? Is it not this very discordance be-
tween the theoretical fossil scheme and the actual succession
of beds as determined by exact methods that has led every
working geologist in this country to abandon the fossils as
the all-important criterion, and to use in their place for the
stages and series the lithological and other characters? Until
this theoretical fetish was set aside stratigraphy and historical
geology, as usually limited, had not made a single step forward
for 50 years.

The subdivisions of the Mississippian series form one oi
the best examples that could possibly be selected to illustrate
the point. Mr. Weller says that the arrangement proposed
“by Williams is a natura! faunal classification, while the second
by Keyes is a stratigraphic classification.” Just what an un-
natural faunal one is we are left to conjecture. The subdivi-
sions of Chouteau, Osage and Ste. Genevieve remain to this
day wholly undefined, except in terms of the stratigraphy.
There exists not even the slightest trace of a criterion by
which to distinguish a Chouteau from a Ste. Genevieve fauna,
or an Osage fauna from an Osage indian. Yet, says Mr. Wel-
ler, “the commonly recognized local geological formations
were placed as accurately as was possible at that time, in their
respective epochs, and further investigation seems to necessi-
tate no different disposition of them.’ Of course not! How
could they be differently disposed in a scheme having no defi-
nition and hence no existence.

Only two persons exist who understand what makes up
each of the three faunas of the Mississippian series. One is the
author of the names himself and the other is his defender. If,:
however, judging from the defense, the Chouteau or Kinder-
hood fauna is a “natural faunal unit,” if the Ste. Genevieve
fauna is a natural and homogenous group” it is to be hoped
that in our final faunal classification of geological time and
substance, we shall have only unnatural faunal groups to work
upon.

112 The American Geologist. August, 1898

But to get back to some of the more essential facts of the
matter: The two classifications are not based upon wholly
different data, as might be inferred from the recent articles.
The one scheme purports to be based entirely upon the in-
fallible fossils; the other on the combined testimony of the
paleontology, the stratigraphy, the lithology and general
physical records of the province. The one considers historical
geology in the narrower sense commonly given in the text-
books; the other in the broader geological sense. The two do
not differ very much in practical application; and not so much
but that they may be readily adjusted.

If professor Williams has indeed proposed names that he
has not yet defined it is no reflection on the essential features
of his classification. It often happens that geological terms
get into literature before it is understood perfectly just what
they are intended to express. In the cases of the three names
under consideration it has been known for several years that
professor Williams has been at work on a monograph of the
Mississippian faunas, in which the three distinctions will be
clearly set forth.

It may be concluded therefore, that the names Chouteau,
Osage and Ste. Genevieve have not been used more widely for
one reason before all others. Previous to their application as
an episode or age title they had been clearly defined and ex-
tensively adopted in other senses. Chouteau limestone had
already been used by Swallow for one of the formations of the
Mississippian series. It was clearly defined; and it is still a
common and useful term. Osage has been already com-
mented upon. Ste. Genevieve was one of Shumard’s names
for a distinct formation; and by him was well defined. It is
bad practice to use such names in very different senses. It is
confusing, to say the least, to perpetuate synonyms even
though they are pet names.

Recent faunal investigations seem to indicate the base of
the Mississippian series to be the bottom of Swallow’s Chou-
teau limestone. In this case, when a time name is to be recog-
nized, Chouteau by modification becomes available. Yet,
curiously enough, Mr. Weller, in his late article discards this
term—the only one of the three that could possibly stand un-
der the laws of priority.

Editorial Comment. 113

Stripped of all their unessentials it appears that the two
classifications of the Mississipian series, if they may be called
two, are to all intents and purposes the same, so far as their
practical workings are concerned. The fact that the terms
proposed by professor Williams are not used is not on account
of any lack of appreciation of his work. It is because the
names are clearly preoccupied to begin with, and because of
the difficulties already mentioned. In this and all similar cases
it is the duty of the active workers to try to get together and
not to attempt to unnecessarily widen unimportant differences,
which can readily be harmonized.

BI TORrAE COMMENT.

THE QUESTION OF THE DIFFERENTIATION OF MAGMAs.

Of the recent publications relating to the origin of the
variations of the igneous rocks of the earth, those of Rosen-
busch, Brogger and Iddings being among the earliest, the
recent brochure of Michel Levy* is one of the most trenchant.
The author gives a short review of the work of the last ten
years as expressed in the articles published by Teall, Rosen-
busch, Brégger, Lang, Iddings, Becker.

Teall, adopting and applying the principle of Soret of a
solution of basic silicates in silicates more acid, explained the
more basic borders of certain laccolytes by the concentration
of the former class of silicates in the cooler portions of the
molten mass, hence on the borders of the laccolyte. But,
(as remarked by the author), unfortunately Fouqueé had al-
ready shown (1879) facts diametrically opposite in the dikes
of Santorin, where the borders are more acid than the centre.

Rosenbusch’s idea of “kerns” or segmentations of the
primordial “magma (1889), is only a further application of
Teall’s hypothesis, supposed to take place at greater depths.
Of these separations, Rosenbusch recognized six primitive

*Classification des magmas des roches eruptives. Par. A. Michel-
Levy. (Extrait du Bulletin Soc. Geol. de France. 3 me. ser. XXV.,
326, 1897).

114 The American Geologist. August, 1898

magmas, distinguished by the relative chemical proportions
existing between the alkalies, lime, magnesia, alumina, iron

and silica. Of this the author remarks that, “except the
foyalitic and the peridotic magmas, the others are arbitrarily

defined and are in reality only an embarrassment in the study
of rocks very dissimilar. The theoretical examination into
the ‘kerns’ of Rosenbusch, distinguished by stoechiometric
proportions, leads at once to a mineralogical determination,
but it reveals then one important lack, viz., the black and white
micas; the excess or the absence of alumina has not been
sufficiently taken into consideration, and the history of acid
and intermediate magmas is singularly obscure.”

As to the “differentiation” of magmas, put forth (1892)
by Iddings, under the idea that the fundamental magma
undergoes sundry changes at volcanic centres producing a
succession of different rocks in a certain order, the author dis-
credits, first, the assumption that such a fundamental magma
exists, and second he considers that the facts of observation do
not warrant such segmentations as have been predicated by
Iddings. However, the author considers the “capital memoir”
of Iddings on the origin of eruptive rocks the most instructive
and the most suggestive. Iddings’ criticisms of the views of
his predecessors are more convincing than his own conclu-
sions.

The cause of such differentiations, if they exist, Iddings
supposes to consist principally in differences of temperature,
the extremely variable dissolvant, changing with the nature of
the magma, is influenced by the conductibility of the walls of
the subterranean chambers which it fills. Pressure is quite
subordinate to heat. This is essentially the idea of Soret,—it
is the theory of a closed chamber (vase clos). In this pro-
cess of differentiation, as set forth by Iddings in his abscissas
and ordinates, the relative proportion of the alkalies, potash
and soda, bears the most important role, being the least
variable in each family. The first rock to appear, in a family
of common consanguinity, according to Iddings, is an in-
termediate one, the later rocks being variations in opposite
directions toward extremes of acidity and basicity. This in-
termediate rock may be the result of differentiation from a
primitive magma, which thus repeats essentially the segmen-

Editorial Comment. 115

tation theory of “kerns’’ of Rosenbusch against which Iddings
himself brings the strongest arguments.

Brogger’s work began in 1890 and has been but lately con-
cluded. He believes the principle of Soret explains the con-
centration of the basic silicates on the borders of laccolytes,
and, consequently the order of appearance of intrusive
magmas—first the basic and then the more and more acid.
In that he agrees with Teall. In order to obtain an approxi-
mation to the nature of the fundamental magma Brogger took
the average of all the intrusive rocks of the region of Chris-
tiania, but, according to the author, the extreme richness in
soda of all the rocks having the “air of family” of the region of
Christiania, precludes the possibility of accepting Brogger’s
result as an indication of the nature of the fundamental
magma.

Lang (1891) classed the magmas of eruptive rocks into
four grand divisions according to the relative total quantities
of lime, soda and potash which they contain, viz:

I. Rocks in which potash predominates over the sum
of soda and lime.

2. Rocks in which soda predominates over potash and
lime.

3. Rocks in which the alkalies predominate over lime.

4. Rocks in which lime predominates over the alkalies.

The author remarks that in such a classification, lime acts
a double role, from a mineralogical point of view—that is,
whether it is associated with the ferromagnesian minerals or
with the silicates of the alkalies; and further, Lang took no ac-
count of magnesia which as it appears plays a capital role in
the natural grouping of magmas.

The four classes of Lang, based on the relative prevalence
of the alkaline elements, are in a measure comparable with the
five principal kerns of Rosenbusch, but in details of applica-
tion they vary widely.

Becker has considered six primitive magmas differing
from each other by their relative contents of calcium, sodium
and potassium, and has devised an elegant geometric method
of representing them graphically, according to their analysis
en bloc. This method is comparable with that of crystallog-
raphy, in which co-ordinates, h k 1, are variable units, and are

116 The American Geologist. August, 1898

laid off on vertical and horizontal axes according to. their
value. Here the relative values of Ca, Na, and K serve the
same purpose. He considers two magmas in which potash is
in excess, and also two each for an excess of lime and soda.
The elements silica, alumina, magnesia and iron are represent-
ed by the vertical lines by which their values are expressed.

The author prefers a different scheme of representing the
comparative analysis of massive rock. This scheme and its
application to a large number of analyses comprise the chief
part of this work.

In the first place he recognizes but two eruptive magmas
having sufficient individuality to enter into a fundamental dis-
cussion. All others he considers arbitrary, accidental or fan-
ciful. These two are:

(1) That which is destitute of ferromagnesian elements
and which Rosenbusch has divided into two parts, viz: foyalitic
and granitic. It is essentially an alkaline magma, from a
chemical point of view, and contains no magnesia.

(2) That which is almost exclusively composed of ferro-
magnesian elements, comprising lamprophyres and_ perido-
tytes, corresponding to the peridotic type of Rosenbusch and
to a part of that of his gabbros. Chemically this contains a
larger amount of magnesia than of lime.

Thus magnesia is taken as the point of departure in his
classification. It represents, with the greatest fidelity, the
relative quantity of the ferromagnesian magma. Iron is more
or less irregularly introduced, lime plays a double role, being
partly involved in the feldspars and partly incorporated in the
bisilicates. or mono-silicates. Magnesia is always character-
istic of the ferromagnesian elements, bisilicates, monosilicates,
black micas, ete., and is present in inverse proportion to
silica.

Secondly the author considers the relation existing be-
tween the alkalies (potash and soda) as the only characteristic
and reliable trait on which to base the division into families.
This is deducible from the study of Mr. Iddings of rocks of in-
creasing acidity (which increases as the magnesia diminishes)
in which it is seen that everything else in liable to irregular
variation. It is an error to complicate the relation of the
alkalies by a comparison with the total lime, which tends to-
ward zero with the ferromagnesian elements.

Editorial Comment. TL,

In the next place he separates the content of lime into
two categories, viz: that concerned in the formation of the
feldspars, and that which enters into the ferromagnesian bisilt-
cates. This separation, however, is intimately associated with:
the disposition of the alumina present, which goes first to satu-
rate the alkalies, the remainder entering into the hornblendes,
micas, etc.

Thus, the chemical elements, and the composing minerals
of all crystalline rocks coming from magmas, are separable
between the two types, the alkaline-earthly type and the fer-
romagnesian type. The dominant characters in each are
given leading roles in his scheme of graphic representation.
In the first he constructs a triangle of potash, soda and lime,
giving each element a position, according to its amount, on
perpendicular ordinates and abscissas, coloring it blue in his
plates. The ferromagnesian triangle is composed in a similar
manner by arbitrarily assigning the leading elements in the
ferromagnesian group to positive or negative positions on the
same axes. This triangle is distinguished by being lined in
black. The exceptional combinations and occasional excesses
of any of the elements are adjusted among themselves by cer-
tain convenient compensations or by special representations.
The triangles thus constituted, placed in juxtaposition, afford
a fundamental graphic presentation of the composition of sim-
ilar or of contrasting rocks. The proportion of silica con-
tained in a rock does not figure in this classification.

The alkaline elements of the magma as represented, in-
clude soda, potash and so much of the lime as is required by
the feldspars. Any excess of soda, as in the soda-bearing
bisilicates, is specially expressed.

The ferromagnesian portion of the magma has a triangle
which expresses the proportion of magnesia, iron and the lime
which remains after the formation of the feldspars. If there be
no lime remaining this triangle is reduced to a vertical line.
Also, in case of an excess of alumina above that required for
the feldspars, this is assigned to the ferromagnesian triangle
and may take the place of a lack of lime in restoring the tri-
angle.

Nearly all grouped chemical analyses hitherto published of
igneous rocks that have been considered allied in origin, such

118 The American Geologist. August, 1898

as those of Iddings, Lang, Zirkel, Rosenbusch, Weed and
Pierson, Washington, Lasaulx, Fouqué, Rust, Becke, Du-
parc, Ritter, Termier and Brogger, are represented by such
triangles in a series of plates, and on the same plates are rep-
resented the triangles of the leading minerals of these rocks.

The ferromagnesian triangle is found to be divisible, first
into four parts, or positions, according to the relative propor-
tions of magnesia and lime included in feldspars, viz: mag-
nesia zero; magnesia less than the lime; magnesia equal to the
lime, and magnesia greater than the lime; and each of these
is further separable into three subdivisions depending on the
presence or excess of alumina, lime or of soda.

The alkaline-earthy triangle is also divided into four parts,
based on the amount of lime present in the feldspars, and each
part is again divided into four more according to the potash it
may contain.

Each analysis, therefore, is represented by two triangles
placed in juxtaposition upon the chosen abscissas and ordin-
ates, and being differently colored give a striking expression
of the composition of the rock concerned. The scale of the
diagrams is two millimetres for one per cent., drawn on or-
diary engineer’s paper lined in squares of one millimetre.

In a general table all rocks, expressed by such triangles,
are also grouped in vertical and horizontal columns, the verti-
cal columns expressing the alkaline or alkaline-earthy constit-
uents and the horizontal the ferromagnesian, with the same
distinctions as employed in the construction of the triangles.

This classification is intended as a fundamental framework
for the comparative grouping of crystalline magmas. It ig-
nores all such accidental elements as structure, age, texture,
and even the mineralogical composition, and embraces only
the quantitative chemical composition. It serves as a point of
departure for the investigation of the question of the origin of
the various igneous rocks and the cause of their variation and
succession, a line of inquiry which the author does not fully
enter upon in this paper—only outlining in a series of critical
conclusions the methods necessary to follow in such an
inquiry.

As an illustration he applies this chemical classification
to a series of igneous rocks recently studied by Weed and

Editorial Comment. 11g

Pierson*, viz: the rocks of the “Castle Mountain Mining Dis-
trict” in Montana, which present, in a high degree, the stamp
of “consanguinity.” After the discussion of this series of
rocks, which is further illustrated by a series of triangular dia-
grams constructed according to the foregoing principles, he
remarks that “this all appears as if, to a pure ferromagnesian
magma but slightly variable, had been added, in succession,
variable amounts of the alkalies, at first rapidly increasing, of
alumina and silica; then, after the point of saturation of the
potash, soda and alumina, silica alone continues to increase
and to take the place even of the ferromagnesian magma.

The diagram of Iddings, put under the author’s form of
expression by contrasting triangles, also shows perfectly the
diverse types of magmas formed successively by such mix-
tures.

In conclusion the author calls attention to sundry theo-
retical considerations bearing upon the variation of magmas,
and discusses briefly certain hypotheses, viz:

1. There are but two magmas that are susceptible of
precise definition—the ferromagnesian and the alkaline. These
have a constant individuality. But it is to be admitted that
neither of these contains their elements in fixed, or even in
stoechiometric proportions, but are quite variable, especially
the alkaline magma in which the per cent of silica can vary
from 51 to 100. The mutual independence of these two funda-
mental magmas is confirmed by a study of a natural series ac-
cording to the method of Iddings. They do not act in the
same manner in their evolution from their. eruptive source. In
general the alkaline magma remains stable while the ferro-
magnesian is replaced in whole or in part, by pure silica.
There is, therefore, a profound contrast between these mag-
mas. The ferromagnesian seems to play the role of an
igneous scoria, while the alkaline, being capable of insideous
injection, seems to be carried, by means of dissolvents and
mineralizing agents, and disseminated sometimes after the
fashion of liquid solution or even of volatile gases.

2. A natural method of differentiation of magmas
ought to fill certain conditions. These conditions must be
found in the deep-seated reservoirs at the points of union of

*Bulletin 139 U. S. Geol. Survey, 1806.

120 The American Geologist. August, 1898

varied portions of these two magmas. The supposed mode
of differentiation must explain not only the birth of a series
of rocks of the same family, but also the origin, at great dis-
tances, of certain series, and on the contrary, also the possi-
bility of remarkable differences between two neighboring cen-
ters. It must, further take account of igneous rocks found at
great depths and of those that solidify at the surface of the
earth. With the former it touches the problem of contact
metamorphism, and that of the striking resemblance of
the crystalline schists to the massive granitoid rocks,
and of their apparently simultaneous production in certain
deep-seated zones of the earth’s crust. This borders on the
question of exomorphous (regional?) metamorphism. Along
with endomorphous metamorphism is found the phenomenon
of the absorption, by certain granitoid rocks, of large amounts
of their surrounding rock walls and the radical transforma-
tion of their magmas by such local absorption.

In connection with the classification of rocks found at the
surface the problem of vulcanism is involved. Indeed the
study of solid magmas spread out on the surface cannot be
separated from that of volatile emmanations, which are of a
formidable volume and of a weight comparable with that of
the fused products. These fumaroles, these clouds of vapor of
water, of chlorides, of sulphides, of different carburetted ex-
halations, continue long after the cessation of the local par-
oxysms. They testify at least to the connection of metalliferous
veins and concretions with volcanic eruptions.

Therefore, exomorphous (or concact) metamorphism lead-
ing to the production of the crystalline schists at the expense
of beds incontestably stratified; the probable existence of deep-
seated zones where general metamorphism gives birth simul-
taneously to the schists and gneisses and to the granitoid
masses; endomorphous metamorphism modifying profoundly
from place to place these granitoid masses by partial solution
and incorporation of the surrounding rock; extended transfer-
ence of certain elements by fumarole action—such are the facts
which a theory of the differentiation of eruptive magmas must
necessarily take account of, without losing sight of the differ-
ent modes of action of the two different fundamental magmas.

3. These facts scarcely appear to be susceptible of being

Editorial Comment. 121

put into accord with the theory of a closed reservoir (vase
clos), such as required by the application of the principle of
Soret :—that is to say of variations of temperature, in a solu-
tion more or less saturated. Here the dissolvent would nec-
essarily be a portion of the alkaline magma, the elements dis-
solved and susceptible of diffusion, of course, would be the
ferro-magnesian magma and silica, one replacing the other.
Such is observably the method of segregation, of differentia-
tion, in a well arranged “family.” But, as already remarked,
this method will never reach the creation of two distinct fam-
ilies having very different proportions of the alkalies, such as
Etna and Vesuvius.

4. Local modification of granitic magmas by endomor-
phous metamorphism explains why certain volcanic series do
not present the air of family, or consanguinity required by the
theory of a universal magma separated by successive segmen-
tations or kerns. In general, further, it is necessary to admit
that in the geosynclinals where accumulate the thickest de-
posits, at the foot of the mountain ranges of the earth. the
isotherms should undergo a rise toward the surface, such as
would permit the fusion more or less aqueous not only oi
magmas already consolidated but even of clastic strata thus
brought into the region of the central heat. Now it is pre-
cisely in these places of greatest accumulation of sediment-
ary formations that successive foldings will be produced, such
as to permit the ascension and intrusion of granitoid rocks.
and later the subsidence of extensive basins like the Mediter-
ranean or the Pacific about the borders of which are located
lines of voleanic rocks. The formation of such magmas
again, can scarcely correspond to the uniformity which is de-
manded by the theory of “closed reservoir,” and of segrega-
tions and differentiation of magmas already differentiated.

5. but the greatest error in the theory of successive dif-
ferentiation consists in not taking any account of the circula-
tion of volatile agents, and of the ceaseless movement which
they must impress on those elements which are susceptible of
being carried by them. Geologists are just beginning to be-
lieve in the modifying power of surface water, simply charged
with oxygen, carbonic acid, or with traces of the chlorides
and fluorides. There is no doubt that they cause the develop-

122 The American Geologist. August, 1895

ment of balls and sponges of silica, the microscopic crystals of
orthoclase and of albite in the stratified rocks. (Lory, Cay-
eux); they give rise to various forms of silica at the outcrops
of the Gypse (Munier-Chalmas), they calcify or decalcify
(Termier) the basic rocks and they dealkalinize the acid; they
produce important rearrangements (de Launay) in metallifer-
ous deposits. Ata distance from granite contacts black mica
is much developed, also various silicates of alumina, and nearer
the contact alkaline feldspars are formed. Lacroix has shown
that in the massive lherzolytes of the Pyrenees, which are en-
tirely destitute of alkalies, the micas are developed, also alka-
line feldspars and tourmaline, all minerals of the alkaline mag-
ma. Here the action of transfer by fumaroles is undeniable.
De Lapparent has dwelt on the importance of solfatrine ac-
tion accompanying modern acid eruptives; and it is known
that certain dykes of granulyte and of pegmatyte act like con-
cretionary veins. This fact was early known and is con-
firmed by numerous observers. The Stockwerks of Zinnwald
and of Altenberg furnished many examples of this to our pre-
decessors.

The author, finally, presents a brief exposé of the hypothe-
sis which he proposes for the forms and variations of igneous
rocks. The active agent of these alterations is believed by
him to be the circulation of fluids under pressure and at a
high temperature through the reservoirs containing the -erup-
tive magma. These reservoirs are filled (1) with the ferro-
magnesian magma which serves everywhere as a scoria for the
impure covering or iron button of the internal mass of the
globe, the interior mass being considered essentially irony; (2)
the rock-products of this button, such as the alkalies,
alumina, silica, which are removable by mineral agents: (3)
the result of a refusion of the lower parts of the crust by the
rising of the isogeotherms, whether such rising be due to an
increase of thinness of the crust or to an ascent of large
-masses of the fused magma. These circulating: fluids com-
bine, under conditions favorable for the operation of the law of
Soret, to produce differentiations, the alkaline substances al-
ways rising and the ferro-magnesians tending to descend.
Hence the first to appear, in case of volcanic action, is the al-

Review of Recent Geological Literature. 123

kaline-magma and the era of activity is terminated by basic

picducts.
Note.—In the foregoing the writer has aimed to give only

the views of the author. It may be added that the nethod
of differentiation adopted by the author varies but little from
the “crenitic” hypothesis of Hunt, differing principally in the
“locus” of the operation. The author supposes the changes
to transpire in deepseated reservoirs, and Hunt at or near the
surface of the earth. N. H. W.

revi OF RECENT GEOLOGICAL
eer. Ly Ee.

The Physical Geography of New Jersey. By ROLLIN D. SALISBURY.
With Appendix, by CORNELIUS CLARKSON VERMEULE. (Vol. IV of the
Final Report of JOHN C. SMOCK, State Geologist.) Pages xvi, 170, 200;
with a relief map, 24 plates (maps, profiles, and views from photographs),
and 37 figures in the text: Trenton, N. J., 1898.

The first division of this report, in 170 pages, by Prof. Salisbury,
treats of the topographic features of the state, and reviews their geo-
logic origin from the close of the Triassic period to the present time,
including alternate uplifts and depressions, with their attendant cycles
of erosion and deposition. The earliest evidences of glaciation, during
the Pensauken epoch, long preceded the deposition of the chief terminal
moraine and of the principal mass of glacial drift. The second division,
an appendix of 200 pages, comprises valuable reference tables and
notes, compiled by Mr. Vermeule, pertaining to physical geography,
county areas, population, and magnetic declination. W. U.

Northward over the ‘Great Ice: a Narrative of Life and Work
along the Shores and upon the Interior Ice-cap of northern Greenland in
£886 and 1891-97; with a description of the little tribe of Smith Sound
Eskimos, the most northerly human beings of the world, and an account
of the discovery and bringing home of the ““Saviksue,”’ or great Cape
York Meteorites. By ROBERT E. PEARY. With maps, diagrams, and
about 800 illustrations. Two volumes: I. Pages Ixxx, 521. II. Pages
xiv, 625. New York: Frederick A. Stokes Co., 1808.

The comprehensive title page of this most admirable work indicates
quite fully its contents, which include extensive observations of high
geclogic, meterologic, and ethnographic value. The story of courage-
ous accomplishment of well laid plans of exploration on the ice-sheet
and northern shores of Greenland, surmounting many difficulties and
intense hardships, is very unostentatiously related. The illustrations

124 The American Geologist. August, 1898

include portraits of the members and patrons of the several expeditions
led by the author, portraits of many of the Smith Sound Eskimos,
who numbered 234 a year ago, and many views of scenery, of Eskimo
dogs, and of sledging on the ice-sheet.

In May, 1894, as Peary narrates, he was guided by an Eskimo to
three large masses of meteoric iron, about 35 miles east of Cape York,
which doubtless originally formed a single meteorite, far larger than
any other known. The situation of these masses in their relation to
the underlying soil and rock implies that the fall took place on a snow-
field, perhaps on the surface of the ice-sheet when formerly more
extended; and it is clearly impossible that these iron masses are of
terrestrial origin like the iron occurring in basalt and in masses weath-
ered from it at Ovifak, 500 miles farther south on Disco island, which
in a different way are equally remarkable and unparalleled in any other
part of the world. All three of the meteoric masses have been brought
to the United States by Peary, two expeditions, the first unsuccessful,
being made for the largest, which is estimated to weigh 90 or 100 tons.
The other two masses weigh about 6,000 and 1,000 pounds. According
to an Eskimo legend, they were a tent, woman, and dog, hurled from
the sky. W. U.

Note sur les gisements dor du Mexigue; par EZEQUIEL ORDONEZ.
(Bul. de la Sociedad Antonio Alzate, Tome XI, pp. 217-240, 1898).

Within recent years there has been rapid increase in the production
of gold in Mexico. This is due not only to the discoveries that have
been made of gold-bearing regions, but also to the improved methods
of the treatment of the ores, not least among which is the great care
that is given to the refining of silver. Many American agents and ex-
perts have visited Mexico, and much American capital has sent its rep-
resentatives throughout the republic; resulting in the organization of
powerful companies for exploiting the ores. The richest regions are in
the northwestern part of Mexico. Lower California and Sonora hold
the first rank. Then follow Sinaloa, Durango, Jalisco, Mexico and Oax-
aca. Exportation has risen from 439 kilos in 1886-87, to 10930 in 1896-
97. Placers are most frequent on the Pacific slopes of the Sierra
Madre mountains. N. H. W.

MONTHLY AWTHORS CAT ATO Gwiz
OF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Ashley, G. H.
Note on fault structure in Indiana. (Ind. Acad. Sci., Proc. for 1897,
pp. 244-250, pls. 1-2.)
*This list includes titles of articles received up to the 20th of the preceding

month, including general geology, physiography, paleontology, petrology and
mineralogy.

Authors’ Catalogue. 125

Ashley, G. H.(Blatchley, W, S. and)

Geological scale of Indiana. (22nd Ann. Rept. Dept. Geol. and Nat.
Resources of Indiana, pp. 17-23, pl. 2, 1808.)

Bagg, R. M.

Report upon the foraminiferal deposits near Bujio, and of the
Empire limestone. [In R. T. Hill’s paper on the isthmus of Panama. ]
(Bull. Mus. Comp. Zool., vol. 28, Geol. ser. vol. 3, no. 5, p. 275, June
1808. )

Bell, Robert.

On the occurrence of mammoth and mastodon remains around
Hudson bay. (Geol. Soc. Amer., Bull., vol. 9, pp. 369-390, June 22,
1808. )

Blatchley, W. S., andAshley, G. H.

Geological scale of Indiana. (22nd Ann. Rept. Dept. Geol. and
Nat. Resources of Indiana, pp. 17-23, pl. 2, 1898.)

Blatchley, W. S.

The geology of Lake and Porter counties, Indiana. (22nd Ann.
Rept. Dept. Geol. and Nat. Resources of Indiana, pp. 25-104, pls. 3-8,
I map, 1808.)

Blatchley, W. S.

The clays and clay industries of northwestern Indiana. (22nd Ann.
Rept. Dept. Geol. and Nat. Resources of Indiana, pp. 105-153, pls. 9-11,
1808.)

Blatchley, W. S.

The petroleum industry in Indiana in 1897. (22nd Ann. Rept. Dept.
Geol, and Nat. Resources of Indiana, pp. 155-184, pls. 12-14, 1808.)

Coleman, A. P.

Fourth report on the West Ontario gold region. (Rept. Bureau
of Mines of Ontario, vol. 7, pt. 2, pp. 109-145, 1808.)

Coleman, A. P.

Notes on the petrology of Ontario. (Rept. Bureau of Mines of
Ontario, vol. 7, pt. 2, pp. 145-150, 1808.)
Coleman, A. P.

Clastic Huronian rocks of western Ontario. (Rept. Bureau of
Mines of Ontario, vol. 7, pt. 2, pp. 151-160, 1898.)
Crawford, J. :

Recent severe seismic disturbances in Nicaragua. (Am. Geol., vol.
22, pp. 56-58, July 1808.)
Cummings, E. R. (Prosser, C. S. and)

Sections and thickness of Lower Silurian formations on West Can-
ada creek and in the Mohawk valley. (15th Ann. Rept. State Geolo-
gist of New York, pp. 615-659, pls, I-12.)

Dall, W. H.

Report upon the paleontology of the collections. [In R. T. Hill’s
paper on the isthmus of Panama.] (Bull. Mus. Comp. Zool., vol. 28,
Geol. ser. vol. 3, no. 5, pp. 271-275, June 1808.)

126 The American Geologist. August, 1898

{Dana, J. D.]

James Dwight Dana. By Prof. James Geikie. (Proc. Royal Soc.
Edinburgh, vol 21, obituary notices, pp. x-xvi, 1897.)

Daniells, W. W.

On the analysis of the water of a flowing artesian well at Marinette,
Wisconsin. (Trans. Wisconsin Acad. Sci. Arts and Letters, vol. 11,
pp. I12-113, 1808.)

Eakle, A. S.

Erionite, a new zeolite. (Am. Jour. Sci., ser. 4, vol. 6, pp. 66-68,
July 1808.)

Elftman, A. H.

The St. Croix river valley. (Am. Geol., vol. 22, pp. 58-61, July
1808. )

Foerste, A. F.

A report on the Niagara limestone quarries of Decatur, Franklin and
Fayette counties, with remarks on the geology of the Middle and
Upper Silurian rocks of these and neighboring (Ripley. Jennings, Bar-
tholomew and Shelby) counties. (22nd Ann. Rept. Dept. Geol. and
Nat. Resources of Indiana, pp. 195-255, pls. 14-18, 1808.)

Fuller, M. L.

Notes on a Carboniferous boulder train in eastern Massachusetts.
(Proc. Boston Soc. Nat. Hist., vol. 28, no. 9, pp. 251-264, June 1808.)
Geikie, James.

James Dwight Dana. (Proc. Royal Soc. Edinburgh, vol. 21, obi-
tuary notices, pp. x-xvi, 1897.)

Herrick, C. L.

The geology of the environs of Albuquerque, New Mexico, (Am.
Geol., vol. 22, pp. 26-43, pl. 6, July 1898.)

Rill ae

The geological history of the isthmus of Panama and portions of
Costa Rica. Based upon a reconnoissance made for Alexander Agas-
siz. With special determinations by W. H. Dall, R. M. Bagg, T. W.
Vaughan, J. E. Wolff, H. W. Turner and Ahe Sjégren. (Bull. Mus.
Comp. Zool., vol. 28, Geol. ser. vol. 3, no. 5, pp. 149-285, pls. 1-10,
June 1898.)

Hollick, Arthur.

Notes on Block island. (N. Y. Acad. Sci., Annals, vol. 11, pt. 1,
pp. 55-88, pls. 2-9, Apr. 30, 1808.)

Kain, S. W.

List of recorded earthquakes in New Brunswick. (Bull. Nat. Hist.
Soc. of New Brunswick, vol. 16, pp. 16-22, 1808.)

Marsh, O. C.

New species of Ceratopsia. (Am. Jour. Sci., ser. 4, vol. 6, p. 93,
July 1808.)

Miller, A. M.

Natural arches of Kentucky. (Science, new ser., vol. 7, pp. 845-846,
June 24, 1808.

Authors Catalogue. 1

iS)
No

Osborn, H. L.

The extinct rhinoceroses. (Mem. Am. Mus. Nat. Hist., vol. 1,
pt. 3, pp. 75-164, pls. 12a-20, Apr. 22, 1898.)
Osborn, H. F.

The origin of the Mammalia. (Am. Nat., vol. 32, pp. 309-334, May
1808. )
Osborn, H. F.

Models: of extinct vertebrates. (Science, new ser., vol. 7, pp. 841-
845, June 24, 1808.)
Parks, W. A.

Geology of base and meridian lines in Rainy River district. (Rept.
Bureau of Mines of Ontario, vol. 7, pt. 2, pp. 161-183, 1 map, 1808.)

erat, J. Fl.

On the origin of the corundum associated with the peridotites in
North Carolina. (Am. Jour. Sci., ser. 4, vol. 6, pp. 49-65, July 1808.)
Prosser, C. S.

The classification and distribution of the Hamilton and Chemung
series of central and estern New York. (15th Ann. Rept. State Geolo-
gist of New York, pp. 83-222, pls. 1-13, 1 map.)

Prosser, C. S.,and Cumings, E. R.

Sections and thickness of the Lower Silurian formations on West
Canada creek and in the Mohawk valley. (15th Ann. Rept. State
Geologist of New York, pp. 615-659, pls. 1-12.)

Ransome, F. L. (Turner, H. W., and)

Description of the Sonora quadrangle. (U. S. Geol. Survey, Geo-
logic Atlas of the U. S., folio 41, Sonora folio, Calif., 1897.)
Ruedemann,R. .

On the development of Tetradium cellulosum Hall, sp. (Am. Geol.,
vol. 22, pp. 16-25, pl. 5, July 1808.)

Russell, 1. C.

Geography of the Laurentian basin. (Am. Geog. Soc., Bull., vol.
30, no. 3, pp. 226-254, 1808.)

Schuchert, Charies (White, David, and)

Cretaceous ‘series of the west coast of Greenland. (Geol. Soc.
Amer., Bull., vol. 9, pp. 343-368, pls. 24-26, June 21, 1808.)
Sjogren, Ahe.

Notes on the eastern section of Costa Rica. [In R. T. Hill’s paper
on the isthmus of Panama.|] (Bull. Mus. Comp. Zool., vol. 28, Geol.
ser. vol. 3, no. 5, pp. 281-282, June 1808.)

Spencer, J. W.

Niagara as a timepiece. (Canadian Inst., Proc., new ser., vol. 1,
pp. 101-103, May 18608.)

Spencer, J. W.

Late formations and great changes of level in Jamaica. (Canadian
Inst., Trans., vol. 5, pp. 325-357, pls. 1-6, May 1808.)

128 The American Geologist. August, 1898

Spencer, J. W.

Resemblances between the declivities of high plateau and those of
submarine Antillean valleys. (Canadian Inst., vol. 5, pp. 359-368, May
1808.)

Stewart, Alban.

Individual variations in the genus Xiphactinus, Leidy. (Kans.
Univ. Quarterly, ser. A, vol. 7, pp. 115-119, pls. 7-10, July 1808.)

Tanne ike Ss

The physical geography of New York. (Am. Geog. Soc., Bull.,
vol. 30, no. 3, pp. 183-225, 1808.)

Tarr, R: S:

Wave-formed cuspate forelands. (Am. Geol., vol. 22, pp. 1-12, pls.
1-4, July 1808.)
Turner, H. W., and Ransome, F. L.

Description of the Sonora quadrangle. (U. S. Geol. Survey, Geo-
logic Atlas of the U. S., folio 41, Sonora folio, Calif., 1897.)

Upham, Warren.

The Mecklenburg or Baltic moraines. (Am. Geol., vol. 22, pp.
43-49, July 1808.)
Van Hise, C. R.

Earth movements. (Trans. Wisconsin Acad. Sci. Arts, and Letters,
vol. II, pp. 465-516, 1808.)
Van Hise, C. R.

Metamorphism of rocks and rock flowage. (Am. Jour Sci., ser 4
vol. 6, pp. 75-91, July 1808.)

Vaughan, T.W.

Report on the fossil corals collected. [In R. T. Hill’s paper on the
isthmus of Panama.] (Bull. Mus. Comp. Zool., vol. 28, Geol. ser. vol.
2) no. 5, p: 275; June 1808)

Walker, T. L.

The crystal symmetry of torbernite. (Am. Jour. Sci., ser. 4, vol. 6,

pp. 41-44, July 1898.)
Weller, Stuart.
Osage vs. Augusta. (Am. Geol., vol. 22, pp. 12-16, July 1808.)

White, David.

Omphalophloios, a new lepidodendroid type. (Geol. Soc. Amer.,
Bull., vol. 9, pp. 329-342, pls. 20-23, May 24, 1808.)
White, David, and Schuchert, Charles.

Cretaceous series of the west coast of Greenland. (Geol. Soc.
Amer., Bull., vol. 9, pp. 343-368, pls. 24-26, June 21, 1808.)
Willmott, A. B.

Michipicoton mining division. (Rept. Bureau of Mines of Ontario,
vol. 7, pt. 2, pp. 184-206, I map, 1898.)

Personal and Scientific News. 129

Woltf; J: E.

Preliminary description of the specimens of igneous rocks in the
collections from the isthmus of Panama and Costa Rica, made by
Robert T. Hill, January, February, and March, 1895. (Bull. Mus.
Comp. Zool., vol. 28, Geol. ser. vol. 3, no. 5, pp. 276-281, June 18908.)

Pee eONA ec AND SCIENTIFIC NEWS.

THe HaypbeEN MEmorIAL GEOLOGICAL AwarD for 1898
has been conferred, by the Academy of Natural Sciences of
Philadelphia, on Prof. Otto Martin Torell, director of the
Geological Survey of Sweden. The award consists of a bronze
medal and the interest on the endowment fund.

THE FOLLOWING NAMED GENTLEMEN received the degree of
Doctor of Philosophy at the Johns Hopkins University in
June, presenting the theses indicated:

Cleveland Abbe, Jr.: “The Rivers of Maryland With
Special Relation to the Evolution of the Piedmont Topo-
graphy.”

A. G. Leonard: “The Basic Eruptive Rocks of North-
eastern Maryland and Their Relation to the Granites.”

€. C. O’Harra: “The Geology of Allegheny County, In-
cluding an Account of the Stratigraphy and Structure of the
Central Appalachian Belt in Maryland.”

Dr. Abbe becomes professor of geology at Western Mary-
land college, Westminster, Md. Dr. Leonard becomes a mem-
ber of the Maryland Geological Survey. Dr. O’Harra be-
comes professor of geology and mineralogy at the South Da-
kota School of Mines.

THE INTERNATIONAL MiniInG ConcGrEss which met at
Salt Lake city, in July, had an attendance of about 200, re-
presenting mostly the mining states of the west, also Mexico,
Peru, Canada, Venezuela and Australia, The next session
will be held in 1899, at Milwaukee. One of the most im-
portant objects of the congress is to recommend amend-
ments to the mining laws of the United States.

Tor NATIONAL GEOGRAPHIC MAGAZINE, Washington,
issued a specially adapted number for July, in recognition
of the Washington meeting of the National Educational As-
sociation. It contains valuable articles suited to the higher
grade teachers, on American Geographic Education by W.
J. McGee; Origin of the Physical Features of the United
States, by G. K. Gilbert; Geographic Development of the
District of Columbia, by W. J. McGee; Historical Develop-
ment of the national capital, by Marcus Baker; Geographic

130 The American Geologist. August, 1898

Work of the General Government, by Henry Gannett; and
on the Geologic Atlas of the United States, by W. ae McGee.
ExTensIVE [RON ORE Deposits in Japan, have been
discussed in ‘Stahl und Eisen,’ by Dr. Th. Mukai. They are
chiefly magnetite and hematite; the amount now known is
estimated at seventy million tons, and new deposits are
continually being discovered. They are destined to have an
important bearing on the industrial development of Japan.

STATE GEOLOGIST BLATCHLEY, of Indiana, in his last re -
port calls direct attention again to the decrease in the nat-
ural gas supply. The productive area is about half what it
was originally. The average rock pressure has fallen from
325 pounds to less than 200 pounds, and salt water is con-
stantly encroaching toward the centre of the field.

THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT
OF SCIENCE will hold its 50th meeting at Boston beginning
August 22d. The president of the meeting is Prof: F. W.
Putnam, for manv years the efficient secretary of the Associ-
ation. The retiring president is Prof. Wolcott Gibbs. The
headquarters of the Association will be at the Massachusetts
Institute of Technology. The section of Geography and
Geology will be presided over by Prof. H. L. Fairchild wet
Rochester. N, Y., and his address will be on “Glacial Geol
ogy in America.” Its secretary is Mr.-Warren Upham of
St. Paul. P

This meeting marks an epoch in the history of the Asso-
ciation and special preparation has been made to enhance
the interest and value of the proceedings. Many attractions
of scientific and social character center in Boston and will
conspire with the unusual programs to cause a_ large
attendance.

HarvarD University. The departments of Geology
and Geography, and of Mineralogy and Petrology, have a
working faculty of fourteen instructors and professors ac-
cording to alate circular. The organization of these de-
partments, under professors Shaler and Wolff, and their
scope of instruction, whether within the laboratory or in
the field, place the institution in these departments in the
fore front in America.

Mr.R. A. Daty, after three years travel and study in
Europe, has been appointed instructor in physiography in
Harvard University, associated with Prof. W. M. Davis.

Dr. GeorGr Baur, oF THE UNIVERSITY OF CHIcaco, late
of Clark University, Worcester, Mass., one of the most emi-
nent and active of the younger paleontologists of America,
recently died, having been absent from his work and seeking
restoration of health during the past year. A brief sketch
is in Sczence of July 15, by O. P. Hay.

LIBRARY
OF THE

UNIVERSITY of ILLINOIS

THe American GeoLocist, Vou. XXII. Puate VIT.

Se a, y |
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ao p sy ig NY
a: On 6 MAP
7 Fe, <5 SHOWING THE KEWEENAWAN
ve z SERIES
Ky 4, Ji
%, “Yee, IN
% 4G: NORTHEASTERN MINNESOTA.
By A. H. ELFTMAN.
. te Gabbro member.

Beaver Bay diabase member.
Red Rock member.

Temperance River member.

eae Later diabase member.

Faults,

THE

AMERICAN GEOLOGIST.

Vor... XXII. SEPTEMBER, 1808. Nox 4.

{Continued from the March No.]

THE GEOLOGY OF THE KEWEENAWAN AREA IN
NORTHEASTERN MINNESOTA. III.

By A. H. EtrrmMan, Minneapolis.
(Plate VII.)

ratio GhOLOGY OR} THE KEWEE-
NAWAN SERIES.
The Map.

The accompanying map, Plate VII, represents the sub-
divisions of the Keweenawan series in Northeastern Minne-
sota. The boundaries of the various members represent the
limits of the main body of each member. The Red Rock
member is so intricately involved with the Gabbro member,
that it is impossible to represent every small area of red rock
within the gabbro mass, upon a map of this scale Owing to
the heavy cover of glacial drift the exact location of the
boundaries is known often only in widely separated areas.
The numerous isolated outcrops of the several members of
the series show the position of the main body of each mem-
ber. In townships 63 and 64 N.R.2 E., T. 63 N. ranges
3 and 4 E. and along the lake Superior coast from Brulé
river to Red Rock bay, the writer has relied entirely upon
previous descriptions and an examination of rock specimens
from that region. The extensive diabase dikes between
Grand Portage bay and Pigeon point, are probably of Ke-
weenawanage. Asno direct evidence to this effect is at hand

132 The American Geologist. September, 1898

it seems advisable to omit these at present. The same may be
said of the Logan sills in the Animikie. In giving referenc-
es, the numbers given in the text refer to the number of the
article in the bibliography of the literature upon the Kewee-
nawan area given in the March number of the Geologist.

CHAPTER III. THE GABBRO MEMBER.

Surface area. The gabbro forms the outer or northern
member of the Keweenawan series. The general shape of the
area is crescentic with the concave side towards lake Superior.
The horns of the crescent are located, the one near Duluth and
the other near East Greenwood lake, T. 64, N., R.2 E. The
chord connecting them is 125 miles long and runs northeast
and southwest. The maximum width of the area is 25 miles.
The surface area is about 2,400 square miles in extent.

The northern boundary of the gabbro is quite regular and
comes into contact with all of the pre-Keweenawan forma-
tions recognized in northeastern Minnesota. In Ts. 49 and 50
N. R. 15 W. the gabbro is in contact with the Animikie slates
of the Saint Louis river valley. Continuing northward the
contact of the formations is concealed by glacial drift for the
next sixty miles. In the vicinity of Birch lake, T. 61 N., R.
12 W., the gabbro is found in contact with the iron-bearing
member of the Animikie. Within the next twenty miles
northeast from Birch lake the contact is with the White Iron
lake granite of pre-Animikie age. Extending eastward to
lake Gabemichigama the gabbro cuts and lies upon the
Lower Keewatin, Upper Keewatin and the Snowbank lake
granite. Between Gabemichigama and Gunflint lakes the
gabbro is in contact with the Animikie, Keewatin and some
ancient greenstones (gabbros, etc.), probably of Archzn age.
From T. 65 N. R. 4 W. to the eastern extremity the gabbro is
in contact with the iron-bearing, black slate and graywacke
slate members of the Animikie.

The southern boundary of the gabbro is irregular on ac-
count of the invasions of other members of the Keweenawan
series. From the south side of East Greenwood lake the
boundary passes westward for thirty miles and turns south
and east through Brulé lake along the Brulé river valley to
the east. side of T.:63 N., R..1 W. In the vacinity of Brule
Mt. and Eagle Mt. the limit of the gabbro zigzags and finally

The Keweenawan in Minnesota.—Elfiman. 133

follows a southwesterly course, through section 6, T. 62 N.
R. 2 W., and through section 15, T. 62 N. R. 4 W. on the
east branch of the Temperance river; continuing westward it
passes through the central part of T. 60 N. R. 6 W. between
lakes Harriet and Bellissima; thence through the southeastern
part of T. 60 N. R. 7 W. and between West Greenwood lake
and Greenwood Mt., in T. 58 N. R. 1o W. At the last lo-
cality it turns sharply toward the south, passes near the north-
west corner of section 19, T. 55 N. R. 11 W. and from there
continues in a southwesterly direction to Duluth. Theses
boundaries give the widest areal distribution of the gabbro.
Within this area are other rocks, some of which are quite ex-
tensive and nearly all of a later geologic age. The chief area
of this kind is the region west and southwest of Brulé lake.

Age of the gabbro. The gabbro has been assigned
geological positions from the base of Animikie to the middle
of the Keweenawan. Dr. W. S. Bayley (41, vol. I., p. 695)
summarizes the various views and concludes that, “‘so far as
the little evidence at hand enables us to judge, the gabbro
* *« * forms a great mass of enormous extent above the
Animikie, but below the interbedded flows and fragmentals
of the Keweenawan series in Minnesota.” After a discus-
sion of the petrographical characters of the gabbo in which
the intrusive character of the rock is emphasized, Dr. Bay-
ley concludes that, “further field work on the geological rela-
tionship of the mass will probably show either that it is a
batholite within the Keweenawan series, well toward its base,
or that like the anorthosites of Lawson it is an eroded ‘mass-
ive’ upon the top of which the later Keweenawan beds have
been deposited.”

All the writers upon this area, now agree that the gabbro
is younger than all of the formations with which it comes into
contact on its northern edge. The gabbro cuts across the
strike of the several formations, penetrates and incloses frag-
ments of them. In places the older rocks were completely
changed at the time of the intrusion of the gabbro mass. On
its southern edge the gabbro member is in contact with the
later members of the series. The red rock member is the most
common of the series. Large bosses and dikes of augite
syenite and granite cut the gabbro near the contact of the main

134 The American Geologist. September, 1898

bodies of the two, and the red rock dikes run for several miles
from the parent mass. In the vicinity of the isolated red
rock bosses the gabbro is usually cut by dikes, from a few
inches to ten feet in width, radiating from the central mass
and increasing in number as the boss is approached. Gabbro
dikes are not known to cut the red rock. In many localities
large masses of gabbro and red rock are in contact, but with-
out any evidence of their relative age. All the evidence, how-
ever, agrees that the red rock acts as an intrusive toward the
gabbro, and that makes the latter an older rock than the red
rock.

The beaver Bay diabase is everywhere separated from the
gabbro and so far as their relation to the other members of the
series shows, these two may be regarded as contemporaneous
rock masses. The Temperance River flows are largely separ-
ated from the gabbro. West of Duluth these flows are un-
conformably above the gabbro. The later diabase cuts the
red rock and gabbro. The evidence thus shows that the
gabbro is above the Animikie or Upper Huronian, and that it
is the lowest or oldest member of the Keweenawan series.

Structure. Yhe gabbro forms an enormous crystalline
mass varying in structure from a homogenous massive to a
banded and apparently bedded rock. The tendency to segre-
gation into large masses composed chiefly of one or only a
part of the minerals is well brought out. The various stages
of segregation are clearly defined and appear in the following.
order:

1. A homogeneous rock in which all of the minerals
present are uniformly distributed.

2. The feldspars, the ferro-magnesian and iron-bearing
minerals become separated into aggregates giving a peculiar
spotted appearance to the rock. The diallage and olivine
form clusters of grains sometimes radially arranged. hese
clusters vary in diameter from one to four inches. The
plagioclase which makes up the greater part of the rock also
fills the spaces between the diallage and olivine grains, and
thus serves as a matrix of these minerals.

3. In many places the gabbro possesses a marked band-
ing. This consists of alternating layers of different mineral
composition, rendered conspicuous by the color of the min-

The Keweenawan in Minnesota —Elfitman. 135

erals. The bands have no general direction of strike and dip,
appear and disappear at random. Some of the bands
are composed of the normal phase of the gabbro; while others
are composed on the one hand almost wholly of feldspar and
of the ferro-magnesian minerals on the other. The bands
vary in thickness from less than an inch to several feet. Each
band is usually quite irregular, varying considerably in thick-
ness in different parts. The lines of division between the dif-
ferent bands usually appear quite sharp and distinct on sur-
face exposures. A microscopical examination of the different
bands shows that the mineral constituents are the same in
all of them, yet in quite different proportion. The texture of
the different bands is usually the same and the minerals of
each band are intimately united with those of the adjacent
bands, indicating that they were solidified at the same time.
The banding is similar to that described and illustrated by
Geikie and Teall in the Tertiary gabbros on the Isle of Skye.*

4. Frequently considerable areas of the gabbro consist
chiefly of one mineral. Prominent illustrations of this are the
feldspar masses in the central part and the magnetite masses
near the edges and in the eastern end of the gabbro area.
There are all gradations in size from these large masses to the
banded and homogeneous rock. The large feldspar masses
frequently contain patches ro to 100 feet in diameter, of the
normal phase of the gabbro. While the outlines of these en-
closed patches is sharp in places, it usually grades gradually
into the feldspar rock. In approaching one of the feldspar
areas the normal massive rock at first shows a spotted and
then a banded structure, which continues up to the isolated
mass. The magnetite deposits are surrounded by similar
conditions. The normal rock becomes banded by a separa-
tion of the feldspar and magnetite. The latter bands some-
times increase in thickness to over 200 feet in width or
widen in places, forming large lenticular and_ boss-like
masses surrounded by the normal phase of the gabbro.

5. The mineral constituents sometimes are arranged with
their longer axes parallel or lying in one plane. The different
minerals are proportionately distributed or are separated into

*Quart. Jour. Geol. Soc. London, 1894, No. 200, pp. 645-660.

£30 The American Geologist. September, 1898

thin bands. The whole produces a gneissic structure similar
to that found in granites. This structure was seen particu-
larly in the northeast corner of T. 61 N.,.R. 10 W. and north
of West Greenwood lake, T. 58 N., R. 10 W.

The preceding structures of the gabbro are primary con-
ditions incident to the solidification of the gabbro magma.
Frequent reference has been made by other writers to the
bedded or sheeted structure of the gabbro. This has been the
chief argument in favor of considering the gabbro mass as
composed of separate surface flows. The structure is a fissil-
ity produced by dynamic forces acting upon the gabbro mass
after its solidification. The strike of the layers is nearly north-
east and southwest, but there is a tendency to conform in di-
rection to the outer limits of the gabbro. The prevailing: dip
is 20 to 45 degrees to the southeast or 20 to 45 degrees to the
northwest. Occasionally the two sets of fissility or cleavage
are found in the same locality and the rock then breaks into
cubes or rhombs instead of splitting into large slabs. The
fissility traverses the rock irrespective of the direction of the
primary structures. When these structures have the same
strike and dip as the fissility the two coincide. A difference
in dip of 10 degrees between these structures will make both
visible. The fissility is common to all parts of the gabbro.
The layers vary in thickness from one inch to ten feet. Cliffs
which possess the fissility and which have been subjected to
extensive weathering have the appearance of a wall of ma-
sonry.

Texture. The size of the minerals constituting the gabbro
varies from fine grained to very coarse grained crystals and
crystal grains sometimes six inches across. The usual size
is medium to coarse grained. The prevailing texture of the
gabbro is the granitic. The other textures are developed only
locally and seldom of great extent. The granulitic texture
is limited to certain contact phases of the rock, and is espe-
cially well developed along the northern edge and in the vicin-
ity of Brulé lake. It is the texture common to the fine grained
parts of the gabbro.

The poikilitic texture is rarely found in the relations of the
essential minerals to each other. The accessory minerals are
frequently enclosed within the larger grains of the essential
minerals.

The Keweenawan in Minnesota.—Elftman. 137

The ophitic (lustre-mottling) texture is found only rarely.
This consists of large grains of diallage enclosing numerous
feldspars similar to the ophitic texture common in_ the
diabases.

The pegmatitic texture is not known as an original texture
in the gabbro. It is common in certain altered phases of the
rock, and consists of the alteration of the feldspars and a sub-
sequent replacement of the altered parts by quartz which is
similarly oriented throughout each feldspar grain. This
process, when completed, gives the appearance of two minerals
originally crystallized within each other. The fibrous inter-
growth of minerals, common in the gabbro, may be a species
of original pegmatitic texture. It consists of minute fibers of
pyroxene and feldspar extending from the crystalline grains
of both minerals, and lying side by side, forming a fibrous ag-
gregate. Under a high power these fibers are shown to be
forms of incipient crystallization branching out from the larger
grains and restricted in their growth by a mutual contact.

Minerals. The primary constituents of the gabbro are,
plagioclase, orthoclase, diallage, hypersthene, augite, olivine,
magnetite, garnet, apatite, pyrite, native copper, chalcopyrite
and graphite. The secondary minerals are hornblende, bio-
tite, chlorite, epidote, quartz, hematite, limonite, leucoxene,
kaolin, serpentine, calcite, malachite, azurite.

Plagioclase is the most abundant component. The min-
eral occurs in broad grains with a fairly regular outline.
Nearly all of the grains possess broad twinning lamellze easily
seen upon a freshly broken specimen. The color varies from .
the clear, colorless fresh mineral to the milky white color of
the highly altered mineral. The cleavages are always promi-
nent and show the striated surface due to the twinning. Un-
der the microscope, twinning, according to the albite law, is
common, and according to the pericline and Carlsbad laws
rarer. The extinction angle varies in different individuals
from 20 to 40 degrees, indicating the presence of labradorite,
bytownite and anorthite. The acicular inclusions character-
istic of gabbroitic feldspar are nearly always present. They
are sometimes parallel with the longer axis of the crystals.
Each feldspar usually has several sets of parallel inclusions
which cross each other at various angles. In many sections

138 The American Geologist. September, 1898

the feldspars are filled almost to opaqueness with dust-like in-
clusions, which, under a high magnification, appear as minute
crystals whose identity cannot be determined. Small grains
of pyroxene, olivine and magnetite are also inclosed by the
feldspar.

Dr. Bayley (41, Vol. I., p. 700) has shown that the chemical
composition and the mean density of the feldspar corresponds
very closely to that of a basic labradorite. The plagioclase is
generally quite fresh. Alteration proceeds around the edges
and along cleavage and fracture lines. The usual product is
kaolin, which appears in fine specks. In some grains the
white alteration product assumes a fibrous form, but the na-
ture of the mineral cannot be determined.

Orthoclase occurs sparingly in the gabbro at Duluth and
along its southern limits. It is indicated in the hand speci-
mens by its red color due to weathering or when fresh by a
dull white color. The presence of potassium in the rock is
shown by chemical analyses.

Diallage is present in irregular, rounded and angular an-
hedrons often two to six inches across. The color is usually
dark brown, varying to pink, which variation may be due to
incipient alteration. The crystal grains are always traversed
by parallel cleavage lines parallel to the axis c. ‘here is also
a distinct parting which cuts the cleavage at an angle of 15
degrees. Pleochroism is absent. Polarization colors are
high and the maximum extinction angle is 39 degrees, when
measured from the cleavage parallel to c and about 25 degrees
when measured from the parting, which is easily mistaken for
cleavage. The mineral has a strongly developed fibrous
structure. Numerous tabular inclusions characteristic of
gabbro diallages occur in many grains. Sometimes they
form parallel bands crossing the crystals. The diallages are
usually associated with the augite, olivine and magnetite.

Hypersthene occurs as small rounded grains in the granu-
litic phases of the gabbro and as large irregular anhedrons,
frequently one-fourth of an inch in length, in the coarser
noryte. The color is black to brown in the hand specimen,
and light brown in the thin section. Cleavage lines parallel
to the axis c are prominent. Fracture lines are not numer-
ous, and when present occur as irregular lines through

The Keweenawan in Minnesota.—Elfiman. 139

the crystal. Twinning has not been noticed in any of the
sections. Pleochroism is strong as follows: ¢ = light green,
a — brownish red, f= greenish yellow or pink to red.
Polarization colors are low and the extinction is parallel on
every axis. The tabular microlitic interpositions usually
found in hypersthene are almost wanting in the mineral in
this rock. These, like the tabular inclusions in the diallage,
are doubtless due to alteration.

Augite occurs in subordinate quantity as irregular anhe-
drons. ‘The color is usually light brown, varying on the one
hand to dark brown in which each grain is uniformly colored
throughout, and on the other to almost colorless. The min-
eral is everywhere traversed by parallel cleavage lines and
numerous irregular fractures with no definite direction re-
ferred to the cleavage. There is no perceptible pleochroism.
Polarization colors are high and the maximum extinction on
the brachypinacoid is about 54 degrees.

Olivine is present as irregular grains having frequently
partial crystal outlines. It is surrounded by the pyroxenes,
and when these minerals are present in the rock the olivine
seldom comes into contact with the feldspar. The rim of
pyroxene is sometimes scarcely noticeable and from this nar-
row extent increases until it forms large plates. Inclusions
of magnetite are nearly always present, and locally are so
numerous as to render the olivine opaque. In some sections
the magnetite assumes a vermicular form, which, on account
of its being found in the perfectly fresh mineral, is probably
primary. A dendritic form of the magnetite is sometimes as-
sociated with the alteration products of the olivine, and is
probably secondary. The color of the olivine is greenish to
yellow. The mineral may be recognized in the hand speci-
men by its yellow, wax-like color when fresh, and by the
brown, earthy appearance when altered. Cleavage lines are
absent, but numerous irregular fracture lines are prominent.
In thin section the surface of the mineral appears rough on
account of the high index of refraction. Pleochroism is ab-
sent, polarization colors are high and extinction is parallel.
The mineral is usually quite fresh in all phases of the gabbro.
In the forellenstein it is more or less altered and the usual
lattice structure accompanying alteration is very prominent.

140 The American Geologist September, 1898

Bayley has shown that the olivine is a hyalosiderite with Mg:
Fe about 1} to rt. Small quantities of the rarer metals, man-
ganese, cobalt, chrominm and nickel also occur in this min-
eral. 7

Magnetite is scattered throughout the rock. Ordinarily
it occurs in small grains usually having perfect crystal out-
lines. Large irregular areas, making up a large part of the
rock, are found in some sections. The proportion increases
until the entire rock is composed of this mineral. Chemical
examinations show that the mineral is sometimes free from
titanium, but usually the latter constituent is present in vary-
ing amounts up to 20 per cent.

Apatite is present only in a small quantity. It occurs as
small greenish to colorless crystals enclosed in the other
minerals of the rock.

Pyrite is common in some parts of the rock. It occurs in
irregular aggregates sometimes an inch across and in thin
sections it appears as small yellow cubes. It is commonly
associated with the magnetite.

Chalcopyrite appears as brass yellow grains or aggregates
associated with the pyrite found in the magnetite deposits.
The mineral is not abundant and seems to be developed only
locally.

Native copper occurs as small strings or grains enclosed
by the other minerals. Occasionally small grains of copper
are imbedded in the clear plagioclase, and again fine threads
of copper unite several plagioclase grains. Some hand speci-
mens show copper up to five per cent of the whole mass.

Graphite occurs as nodules and micaceous grains in the
gabbro at its contact with the black slate member of the Ani-
mikie. The mineral is derived from the carbonaceous ma-
terial in the slate, and seldom is found far within the gabbro.
It has a gray color. When wet the nodules may easily be cut
with a knife, upon exposure to the air and when dry the
graphite becomes hard and brittle.

Garnets occur sparingly in small red grains near the con-
tact with the older rocks and near some of the magnetite de-
posits.

Hornblende is never found in the perfectly fresh rock.
It is always associated with the diallage and augite. There

The Keweenawan in Minnesota.—Elfiman. 141

are all gradations from a narrow rim of hornblende around a
plate of pyroxene, or a few small areas of hornblende within
the pyroxene to a plate of hornblende with a few scattering
areas or a single core of pyroxene. Some sections of the
highly altered rock contain only hornblende, but in several
sections from the same hand specimens there is nearly always
some trace of diallage. Since the hornblende is always closely
associated with the pyroxene and since it is absent from the
unaltered rock it is concluded that the hornblende in the gab-
bro is always of secondary origin. The mineral has a light
to dark green color. Pleochroism is strong and the maxi-
mum extinction angle is about 22 degrees. The columnar
structure of uralite is prominent. Frequently the mineral is
finely fibrous.

Biotite is common in the altered parts and absent in the
fresh portions of the gabbro. It occurs as thin scales and
irregular crystals sometimes two to three inches across. The
outer parts of some of the large pyroxene crystals consist of
biotite. - In thin section it is seen surrounding plates of py-
roxene and hornblende. These three minerals are some-
times found in the same individual, the biotite forming the
outer rim, the hornblende the middle and the pyroxene the
inner core. The biotite also forms a mosaic with highly al-
tered pyroxene and hornblende. It occurs as a reaction
product between magnetite and plagioclase. Small flakes of
the mineral within the feldspars indicate the former presence
of magnetite. Instead of single plates replacing the pyroxene
there are in some sections beautiful rosettes of biotite. The
mineral varies from a dark brown to reddish brown. The
latter color is found chiefly in the biotite surrounding the
magnetite. Cleavage is nearly always prominent. From its
association of biotite with the other minerals it is undoubtedly
always secondary.

Chlorite occurs as an alteration product derived largely
from the ferro-magnesian constituents of the rock. It is pres-
ent in minute greenish flakes and needles sometimes arranged
in rosettes and fibrous aggregates, which, between crossed
nicols, show a dark cross.

Epidote, like chlorite, is not abundant, and occurs as an
alteration product. It is present in the altered feldspar, and
other minerals, as minute yellow flakes. .

142 The American Geologist. September, 1898

Quartz is abundant as a secondary mineral in some of the
altered phases of the gabbro. It is never present in the fresh
rock. With the feldspar it forms a pegmatitic texture like
that found in the augite syenite of the red rock member de-
scribed by Irving (14, p. 114). In some sections grains of
feldspar are entirely replaced by quartz, which then has a typi-
cal granitic texture. There are all gradations in texture be-
tween the feldspar and the quartz. The former in some sec-
tions shows only a few small specks of quartz, which becomes
more abundant until the feldspar is entirely replaced. The
quartz has also been formed between crystals of feldspar, in
which case it replaces some of the other minerals. In some
sections it is filled with minute inclusions of a dark substance.

Hematite occurs as small red flakes and as an earthy de-
composition product in some of highly altered gabbro. When
the iron bearing minerals are abundant the hematite gives a
brick red color to the rock.

Limonite is present as a yellow earthy decomposition
product. It is noticeable in small quantities in nearly all sec-
tions which show alteration.

Leucoxene occurs in small quantities as an alteration
product of the titaniferous magnetite. It has been noticed as
a white powder in some of the highly altered magnetite
masses, and in thin sections it is found as a white border
around some of the magnetite grains.

Kaolin is present as decomposition product from the felds-
par. It is present usually in fine flakes within the feldspar.
In some parts of the decomposed rock the feldspar is entirely
altered to kaolin, which then forms a dull white substance
easily powdered.

Serpentine is the usual alteration product of olivine, and is
abundant in the forellenstein. It occurs as a fibrous sub-
stance often stained red by iron oxide.

Calcite occurs in small veins in the gabbro, and is the
result of alteration in the rock. Some of this mineral may
be derived from outside sources, but part of it, which is asso-
ciated with the decomposed rock, is probably derived directly
from the gabbro.

Malachite occurs as a green coating upon the rock and
in fractures in localities where copper and chalcopyrite occur
in the gabbro.

The Keweenawan in Minnesota —Elfiman. 143

Azurite occurs as a blue coating derived from the copper-
bearing minerals.

Varieties. The entire gabbro mass consists of minerals
common in gabbros. ‘These minerals vary in proportion in
different parts of the rock. There is every gradation from
the uniform mixture of minerals to masses composed entirely
of one mineral or in which the other minerals may all be
present but forming only a small per cent of the whole. While
the whole rock is included under the general term gabbro, it
seems that the various mineral combinations which have per-
sistent characters are of sufficient importance to merit varietal
names. ‘The separating into varieties is due to forces acting
at the time of solidification. The principal minerals are nearly
always present either as essential or accessory, according to
the variety.

Normal phase of the gabbro. This phase of the rock
consists essentially of plagioclase and diallage. The former
is more abundant. Olivine is nearly always present as an ac-
cessory mineral. Since the absence of olivine is only excep-
tional it appears that the division into olivine and olivine-free
gabbros is wholly superfluous. in the Minnesota gabbro.
Augite and magnetite are never present in large quantities.
The prevailing texture is coarse grained with the average size
of the grains between one-eighth to one-fourth of an inch
across. While the minerals are usually in broad plates, fre-
quently they occur as long, narrow individuals similar to those
found in diabase. All of the mineral constituents can gen-
erally be identified in the hand specimen. The prevalent color
is light gray on the freshly fractured surfaces and dull white
on exposed surfaces.

Forellenstein (troctolyte). The olivine in the normal
phase of the gabbro varies in inverse proportion with the
diallage. When the olivine predominates over the diallage,
the other constituents remaining the same, the rock ap-
proaches the character of a typical forellenstein. In many
areas of the gabbro, notably in T. 61 N. R. to W. and adjacent
townships, the olivine has nearly replaced the diallage, which
occurs only in a very subordinate quantity. The rock has a
spotted appearance and is usually characterized by a banded
structure. The olivine, when altered, changes to serpentine

144 The American Geologist. September, 1898

and red earthy iron oxides, which are often sufficient to give
the rock a brick red apeparance. The prevalent color is dark
brown. The feldspars surrounding the altered olivine are
always filled with fractures arranged radially around the oli-
vine. According to Prof. Judd, this shattering of the feld-
spar is produced by the hydration of the olivine, during which
process, on account of the increase in the bulk of the mineral,
there is an expansion on this part of the rock, and a fractur-
ing of the unaltered minerals around the olivine.*

Noryte. Hypersthene is frequently present as an accessory
mineral in the gabbro mass. It sometimes predominates over
the other pyroxenes and olivine, even being the only ferro-
magnesian mineral present. The rock then becomes a noryte.
Around West Greenwood lake in T. 58 N. R. to W. this rock
is extensively developed. It is coarse grained and unaltered.
The color is light gray with brown spots evenly distributed.
The texture is granitic. The noryte occurs quite extensively
along the northern border of the gabbro, where it was recently
described by Bayley (41, vol. III., pp. 1-20). The texture of
the rock there is granulitic and is regarded as a phase of the
gabbro due to contact phenomena. In section 21, T. 63 N. R.
4 W. and in the region west of Brulé lake there is also an ex-
tensive development of the granulitic noryte. This rock is
fine grained and usually has a darker color than the normal
phase of the rock. In the last named localities it is intimately
associated with the magnetite deposits of that vicinity.

Anorthosyte. This is ccmposed essentially of plagioclase
with the other mineral constituents as accessory. The usual
proportion being 90 to 95 per cent of plagioclase and 10 to 5
per cent of pyroxene, olivine, magnetite, etc. This rock is
apparent in the central part of the gabbro area, and it has
been noticed especially south and west of Little Saganaga
lake, T. 64 N., R. 5 W., and for fifty miles westward of that
locality as far as the gabbro remains uncovered. The anor-
thosyte has a white color and usually stands out quite promi-
nently from the other phases of the gabbro.

Pyroxenyte. When the rock is composed entirely of the
pyroxene minerals it is dark in color and much heavier than

*Quart. Jour. Geol. Soc. London, 1886, No. 165, vol. XLII, p. 86.

The Keweenawan in Minnesota —Elftman. 145

the normal phase of the rock. The next variety is generally
closely associated with this.

Peridotyte. This consists chiefly of olivine together with
some pyroxene. The pyroxenyte and peridotyte are quite
limited in extent. The rocks of this variety found along the
northern boundary of the gabbro are. not part of that rock,
but are referred to the contact action of the gabbro upon the
older rocks,

Magnetite. Small masses of titaniferous magnetite
are scattered throughout the gabbro. Extensive masses are
known only along the northern border and in the eastern
part of the gabbro. These deposits of magnetite are espe-
cially numerous in the region between Brulé lake and the
northern limit of the gabbro. The ore bodies are found in
three belts running east and west. The northernmost follows
the boundary of the gabbro. The second runs through the
southern part of township 64 north, and the southern or third
belt runs south of Brulé lake through the central or southern
part of township 63 north.

The magnetite deposits are usually associated with granu-
litic noryte, which is always slightly the older of the two.
The noryte is considerably broken and traversed by veins of
magnetite extending from the large masses around its edge.
From the main mass of the magnetite, stringers and apophyses
run several hundred feet into the massive gabbro. Frequently
the magnetite occurs in numerous parallel bands several
inches to a foot in width, which alternate with bands of the
associated gabbro. As many as twenty-five of these bands
have been noticed within a belt ten feet wide. There are all
proportions of minerals between magnetite and the normal
phase of the gabbro. The variations of the ore as seen in a
shaft 19 feet deep on section 21,T. 63 N., R. 4 W., is as follows:
At the surface the rock was composed of solid coarse magne-
tite stained green with a coating of malachite. The pure mag-
netite continued downward for five feet when a few grains of
chalcopyrite, pyrite and plagioclase were found. At seven
feet below the surface the magnetite became fine grained, and
a small amount of plagioclase and pyrite continued. Olivine
appears as bright, vellow grains. Continuing downward the
plagioclase and pyrite disappeared and the lower ten feet of thé

140 The American Geologist. September, 1898

shaft were in magnetite with the olivine increasing in pro-
portion.

The ore has a shining black luster, is brittle and usually
coarse grained. Thin sections of the apparently pure ore
generally show the presence of small particles of plagioclase,
and sometimes of other minerals. Copper and chalcopyrite
are associated with magnetite. Native copper was found by
the writer in outcrops north of Tucker lake in the north part
of T.64 N., R. 3 W., and from the shaft in the N. W.4 ofS. E.
4 sec. 21, T. 63 N., R. 4 W. It is reported from other localities
near these locations. Some specimens of rock contain over
five per cent of copper.

Chemical analyses show quite a variation in the compo-
sition of these ores. An analysis by the writer of an ore from
section 21, T. 63 N., R. 4 W., gave silicia, 6.08; alumina, 3.82;
lime, 1.69; titanium oxide, 14.73; magnetite, 71.; nickel oxide,
2.65; sulphur, trace. The lime and alumina are accounted for
by the presence of a triclinic feldspar.

Titanium is sometimes absent. Cobalt, manganese and
chromium are sometimes found in addition to the constituents
given in the above analysis. The metallic iron varies from 49
to 60 per cent. These extensive magnetite deposits at pres-
ent afford the only ores from the gabbro of probable economic
value. An exhaustive study of the rarer metals in this ore
has not vet been accomplished. Some analyses show the
presence of small quantities up to two or three per cent of
these metals in certain localities.

Orthoclase gabbro. This variety is so called on account
of the presence of the mineral orthoclase. Since this mineral
is never abundant the orthoclase gabbro is quite limited in ex-
tent. It seems that the orthoclase might be regarded as an
accessory mineral rather than to form a separate variety.

Itis hard to distinguish the relative age of each variety. The
granulitic noryte is slightly older than the rest of the mass,
which may be considered as of one age. The noryte in places
forms angular blocks cut by and enclosed in the rest of the
gabbro. In other places the noryte and gabbro grade into
each other. The relative age of the individual minerals may
assist in determining the relative age of the varieties of the
gabbro mass. The minerals were formed in the following

The Keweenawan in Minnesota —Elfiman. 147

order: Apatite, magnetite, olivine, hypersthene, augite, dial-
lage. The plagioclase seems to be contemporary with the
other minerals. The magnetite, while beginning to form
before the olivine, did not cease to form until some time after
the latter began. Since the olivine is usually surrounded by
the pyroxene, its crystallization was apparently completed be-
fore the remaining minerals were formed. Hypersthene next
began to form and continued after the augite began. The
augite usually surrounds the former, but small grains of au-
gite are also enclosed by some of the hypersthenes. The py-
roxenes and plagioclase probably began to form about the
same time. So far as the relation between the two shows, it
seems that the plagioclase whose outlines depend upon the
irregular anhedrons of pyroxene is younger than that part of
the pyroxene, and that the plagioclase enclosed by the ophitic
areas of pyroxenes is older than the latter mineral. There is
no evidence that there was a cessation in the crystalization of
the rock, but it seems that the process was continuous.

Alteration. —TVhe alterations of the minerals are as follows:
The pyroxenes change directly into hornblende, and _ biotite.
The hornblende also changes to biotite. Olivine forms ser-
pentine. Plagioclase is replaced by quartz and kaolin. Biotite
forms a reaction product between plagioclase and magnetite.
Chlorite, epidote, iron oxides, kaolin, leucoxene, serpentine,
calcite and the copper carbonates are decomposition products.

The alteration of the mineral components of the gabbro,
locally sometimes proceeds far enough to form a rock whose
mineral composition is quite different from that of the original
gabbro. An example of this is found at places along the
southern edge and in the eastern end of the gabbro area. The
rock is originally composed essentially of plagioclase, ortho-
clase and pyroxene. The pyroxene is changed to hornblende
and biotite. The feldspars are in part decomposed into kaolin
and silica. Quartz replaces the decomposition products. The
rock is then composed essentially of plagioclase, orthoclase,
quartz, hornblende and biotite, and becomes a granite in com-
position. In the field it is sometimes difficult to mark the
boundary between this altered phase of the gabbro and the
augite syenite of the red rock member.

Contact Phenomena. —Yhe gabbro presents remarkable

148 The American Geologist. ° September, 1898

contact phenomena along its northern edge. The older rocks
with which it is in contact are nearly always highly changed
from their original condition. The following localities ex-
hibit the most conspicuous exposures of contact:

T. 65 N. R.3 W. At the western end of Loon lake the
gabbro lies upon the graywacke slate members of the Animi-
kie. This is a sandstone and quartzyte. At the contact and
for ten to fifty feet from the gabbro the quartzyte is com-
pletely changed and consists of irregular, angular and in-
terlocking grains of quartz, having a typical granitic structure.
Hornblende and biotite occur in large plates and surround
quartz grains as a matrix in a poikilitic manner. Other parts
of the Animikie at this locality have been changed to a biotite
schist. The gabbro has a uniform coarse grained texture.

Akeley lake, T.'65 N. R.4 W. Here the gabbro is found
in contact with the iron bearing and black slate members of the
Animikie. These members are entirely recrystallized by the
effect of the gabbro. The iron bearing member forms a
coarsely crystalline rock composed of quartz, pyroxene, olivine
and magnetite. The black slate member was changed into
biotite schist, and crystalline quartz rock. The carbonaceous
matter was collected as graphite which occurs extensively in
the contact zone. The gabbro of this locality is a uniformly
coarse grained normal phase of the rock.

T. 63 N. R. 8 W. South of Disappointment lake the gabbro
is in contact with a conglomerate and beds of iron ore. The
older rocks are entirely recrystallized though retaining their
stratification to a remarkable degree.

Sec. 30, T. 62 N. R. 10 W. In this locality large blocks of.
a quartzose pyroxene magnetite rock, like that at Akeley lake,
occur in the gabbro two miles from its northern border.

Birch lake, T. 61 N. R. 11 W. North of the lake the gabbro
is in contact with quartzose pyroxene rocks, which extend
westward and are found to be a part of the iron bearing mem-
ber of the Animikie. (43, pp. 159-169.) Southwest of the
lake the gabbro produced biotite schists at the contact with
the Animikie rocks.

Many of the quartzose, pyroxenic and olivinitic magnetites
occuring at the preceding localities have been regarded by
Bayley (41, Vol. II, p. 814), as peripheral phases of the gabbro.

Raised Shorelines at Trondhgem.—Upham. 149

The writer excludes these rocks from the gabbro for the fol-
lowing reasons:

1. These magnetite rocks are stratigraphically. continu-
ous with the Animikie iron bearing rocks, and at Birch and
_ Akeley lakes the unchanged rock can be traced by successive
steps into the crystalline rocks, composed of quartz, pyroxene,
olivine and magnetite. The metamorphosed rock retains the
banded structure of the original rock. The rock is free from
titanium. The chemical composition of the recrystallized
rock corresponds closely with that of the unaltered rock.

2. The gabbro always acts as an intrusive toward the
quartzose pyroxene rocks, the contact between the two is
sharp. Large irregular blocks of the latter rock are entirely
surrounded by the gabbro. The gabbro is nearly always a
uniformly coarse grained normal phase when found in con-
tact with the older rocks. The gabbro magnetites nearly al-
ways contain considerable titanium.

{European and American Glacial Geology Compared, VIII.]}

RAISED SHORELINES AT TRONDHJEM.

By WARREN UPHAM, St. Paul, Minn.

The younger Hugh Miller visited the city of Trondhjem*
in October, 1884, and, in a paper read before the British As-
sociation in 1885, reported his identification and mapping of
forty-three raised shorelines, eroded in slopes of glacial drift
below the very remarkable shore, 525 feet above the sea, which
is eroded in the rock of the hill about a mile west of the city.
Above a little bay at Leangen, two miles east of Trondhjem,
Miller noted thirty shorelines in the first 300 feet of ascent
from the fjord to a distance of one mile and a half from its
shore. Three or four others were found in the next 50 feet

*Also often spelled Throndhjem by English writers. Its meaning is
the Zhrone Home, having been for centuries the capital of the country.
It is still honored as the place of coronation of the kings of Norway and
Sweden, the present King Oscar II being crowned there in 1872.

150 The American Geologist. September, 1898

of ascent, and nine or ten others higher, before reaching the
level of the sea-cliffs of rock.*

Remembering these published observations, I wished to
see Trondhjem, not only on account of its historical interest
as the ancient capital of Norway, but also for personal exam-
ination of these Late Glacial shorelines. Four days, July
17th to the 21st, 1897, were spent there, at the latitude of 63°
25’, about 210 miles south of the Arctic circle, this being the
most northern part of our journeying. The temperature was
delightful, warm but not hot; and the very clear air permitted:
extensive views from the adjoining high hills, looking far to
the north and northeast along the great Trondhjem fjord,
which takes its name from this city built on its southern shore
at the mouth of the river Nid. During the time of our stay
the city was thronged with its 30,000 people and many visitors,
in the festivities of celebrating the nine hundredth anniversary
of its foundation. King Oscar arrived from Stockholm for
this celebration on the 17th, and remained three days. Though
it was a month after the summer solstice, the days were still
very long, the sun rising soon after two o’clock and setting
a quarter before ten. On the evening of the 20th the bright
and long continuing sunset illumination of the clouds was
magnificent. The preceding evening I had returned very
late from a walk of about twenty miles, and found that at mid-
night the twilight was sufficient for reading a book or news-
paper.

The shoreline mentioned as worn in the rock (gneiss, mica
schist, diabase, etc.) of this vicinity, marking probably a pro-
longed stage of the depression of the land at the time of the
final retreat and departure of the ice-sheet, is best exhibited
on the east slope of the rugged, mostly wooded hill named
Gjeitfjeld, which rises steeply from the southwest shore of
the fjord. In several places along a distance of about a mile,
the more outstanding portions of this hillside, which is seen in
full view from Trondhjem, looking west, are eroded into pre-

*Nature, XXXII, 555, Oct. 8th, 1885. This paper gives the altitude
of the “upper line” of the raised sea-cliffs of rock as 580 feet, referring
probably to the upper part of the cliffs. Their base, where the rock was
undercut by waves and floating ice at the old sea level of the Champlain
epoch or closing part of the Ice age, is 160 meters (525 feet) above the
sea, as Shown on the contoured map of Trondhjem and its environs pub-
lished there by A. Bruns, in 1885.

Raised Shorelines at Trondlyem—Upham. 151

cipitous cliffs of bare rock from 25 to 75 feet high, their some-
what indefinite bases being approximately 525 feet above the
fjord; but between the sea-cliffs slightly indented parts of the
old shore, comprising together more than half of the same
mile of distance, are not distinguished from the general
wooded slope. Against this shore the waves raised by north-
east winds, blowing unimpeded for nearly thirty miles down
the fjord, doubtless bore much floe ice and the fragments of
bergs discharged from the receding ice-front in water which
then was 600 to 2,000 feet deep. Other parts of the shores of
the Trondhjem fjord and. its branches, both west and east of
the city, seen along an aggregate extent of more than fifty
miles, rarely exhibit this ancient shoreline conspicuously; and
indeed it is not recognizable in any general view, but would
require a survey with levelling for its accurate location, along
nearly all its course.

It is well displayed, however, on the fjordward sides of
two small hills, named Blybjerget and Sverresborg, which
stand respectively close west and east of the road that ascends
southwesterly from Ihlen, the western suburb of Trondhjem,
at the distance of three-fourths of a mile from Ihlen and the
present fjord shore. <A nearly vertical rock cliff, about fifty
feet high, bounds the north and west sides of the flat-topped
Sverresborg, which is so called from its having been the site
of a castle of King Sverre, 700 years ago. At the foot of the
cliff a grassed terrace, partly encumbered by fallen rock
masses, has a width of fifty to sixty feet along its extent of an
eighth of a mile; and from its verge a talus descends some fifty
feet to the margin of a cultivated field. On the opposite hill,
Blybjerget, at the same level of about 525 feet, a gravelly and
sandy terrace, mostly three or four rods wide, but in part,
where it is built out northeastward by converging currents,
ten to fifteen rods wide, reaches nearly a quarter of a mile.
The higher hilltop is wooded; the old shore terrace is a narrow
grassy pasture; and the slope below is mowing land.

Maps of Trondhjem and its vicinity usually show the rock-
cut shore west of the city, designating it as a “‘strandline,” and
representing its sea-cliff and terrace as continuous, instead of
which they are interrupted by longer parts of the old shore
which are not distinctly eroded. The amount of wave work at

152 The American Geologist. September, 1898

the 525 feet level, however, appears to surpass that of any
single one of the thirty successive shores of the glacial lake
Agassiz. It was therefore my expectation, suggested by Mil-
ler’s paper, that clearly marked beaches, similar to those of
lake Agassiz and of the glacial lakes in the basins of the pres-
ent great lakes tributary to the St. Lawrence, or like those of
Glen Roy, would be found wherever drift-covered slopes de-
scend from the level of the rock strandline. Such slopes, well
adapted for the formation of shorelines, whether by erosion
or by the accumulation of beach ridges of gravel and sand,
were examined upon large areas near Trondhjem, also west
and south of the adjoining hilly tract which culminates in
Graakallen (1,840 feet, about four miles west of the city), and
on the south side of the fjord along the route of the railway
passing eastward. But well defined shorelines were observed
in only a few places, and then only for short distances, chiefly
where inflowing streams brought small delta deposits, or
where some exceptionally favorable outline of the shore in its
relation to the waves and currents permitted a short beach
ridge or terrace to be formed.

Stages of pause in the emergence of the land are only very
indistinctly and doubtfully shown by these deltas and beaches;
and the correlation of their fragmentary development, so as to
trace any shore continuously even on the most favorable drift
slopes, is possible only by levelling across many tracts un-
marked by shore erosion or deposition. In contrast with the
usual continuity and clearness of the lake Agassiz and Glen
Roy shores, my observations suggest that the time occupied
in the re-elevation of the region of Trondhjem from its Cham-
plain subsidence was probably more brief than the duration
of these glacial lakes in North America and Scotland. The
Recent period, as indicated by the present shorelines appears
to have greatly exceeded the short time of continuance of the
Champlain depression of this part of Norway after its ice bur-
den was melted away.

In southern Sweden a most instructive series of Glacial
and Postglacial epeirogenic movements has been ascertained

Raised Shorelines at Trondlyem—Upham. 153

by Baron De Geer.* From its high preglacial elevation the
land there sank in the later part of the Glacial period much
below its present hight. It was then re-elevated to such ex-
tent that the Baltic sea became a great freshwater lake. Next
it was again depressed lower than now, and at present it is
slowly rising.

The Late Glacial or Champlain subsidence was greatest
on the west side of the Gulf of Bothnia, attaining there a max-
imum of 885 feet at the highest observed limit of its raised
shorelines, and in the interior of the peninsula it doubtless ex-
ceeded 1,000 feet; but its amount decreased outward on all
sides, being in the vicinity of Trondhjem about 525 feet, and
much less on the outer parts of the Norwegian coast. In
northern Denmark, I observed the very conspicuous Cham-
plain shoreline from four to eight miles south of Frederiks-
havn, where it is marked by a continuous sea-cliff forty to sev-
enty-five feet high, eroded in morainic till, with its base, which
was at the old sea level, about forty feet above the present
seashore.

Whether the Trondhjem district has experienced the full
series of pendulumlike oscillations in the relations of land and
sea which are definitely known in the south part of this penin-
sula, being carried upward from the Champlain depression
higher than at present, then sinking, and now again rising,
can probably be determined by careful mapping and study of
the modified drift in the Gula, Nid, and Stjordal valleys, tribu-
tary from the south and east to the Trondhjem fjord and its
arms. ‘These valleys, in large part narrowly enclosed by high
and precipitous mountains, bear on their sides numerous ter-
races of gravel and sand up to hights of 100 to 300 feet, or
more, above the streams; and at somewhat greater altitudes
they often display little delta areas of the same modified drift,
level and cultivated on their extent of perhaps one or two
acres, while all the adjoining valley side is rugged rock with a

*On Scandinavian Changes of Level during the Quaternary Period,
Report No. 98 (Series C) of the Geol. Survey of Sweden, 66 pages, with
maps, 1890; Bulletin, Geol. Soc. of America, III, 65-68, with map, 1891;
Proc. Boston Society of Natural History, XXV, 454-477, 1892, (also in
the Am. Geologist, XI, 22-44, Jan., 1893); On the Geographic Conditions
of Scandinavia after the Ice Age, Report No. 161 (Series C), Geol. Sur-
vey of Sweden, 160 pages, with 29 text illustrations, and six map plates,

1806.

154 The American Geologist. September, 1895

scanty forest growth of dark firs and occasional white birches.
The gravel and sand terraces and deltas, occurring at all hights
up to the old sea level (and less plentifully represented at slight
altitudes above the bottoms of the valleys along their upper
courses before reaching the Champlain level), record much of
the history of the glacial recession and the concurrent uplift-
ing of the land from its subsidence. The lack of large alluvial
areas at the mouths of these rivers seems to testify that the re-
elevation at first surpassed the present hight; but to learn all
the details of the epeirogenic oscillations, with pauses, which
the region has undergone, so far as they can be read in these
valleys, would require probably a whole summer of field work.

The most important comparison with America that I dis-
cern for the Trondhjem raised shorelines consists in their
scantiness, which is fully paralleled by Maine, the Eastern
Canadian provinces, and the St. Lawrence valley. Although
the land there at the close of the Ice age was on large coastal
tracts 300 to 600 feet lower than now, as in Norway and
Sweden, its emergence occupied too brief time to allow the
waves to carve the shores deeply or amass well developed
and generally continuous beach ridges.

GLACIAL GEOLOGY IN AMERICA.*

By HERMAN L. FAIRCHILD Rochester, N. Y.

INTRODUCTION.

The life of this Association, with that of its predecessor,
covers precisely the period since the glacial theory was intro-
duced to American geologists. It seems highly appropriate,
upon the occasion of the jubilee meeting of this society, to re-
view briefly the history and growth of glacial geology in
America and to give credit to the men who were pioneers or
who have been most influential in the development of this
young and vigorous branch of earth-study.

In the limits of this paper it is impossible to call the roll of

*Vice-presidential address. Section of Geology and Geography.
A. A. A. S., Aug., 1898.

Glacial Geology in America —Fairchild. 155

all the investigators in American glaciology,and apology is
here offered for many omissions and possible errors.*

DHE GLACIAL THEORY.

Announcement. —The “drift” of the northern United
States and Canada was not neglected by the self-taught geol-
ogists of the early part of this century. Frequent references
occur in the writings of those years to the striz and polished
rocks, the stony clay, the deposits of sand and gravel and par-
ticularly to the conspicuous erratics and perched boulders.
These phenomena were commonly attributed to the agency of
violent floods, and were called ‘‘diluvial.”” They were, however,
so unlike any products of observable aqueous action that the
conditions of their formation were a subject of imagination
rather than of scientific inquiry. But this conception of water
as the chief or only agent concerned in the production of the
drift and striz gained such general assent and so bound the
minds of the older American geologists that the glacial theory
was not given at first even a respectful hearing, and it was not
accepted until long after a majority of foreign geologists had
adopted it for western Europe and the British Islands,—not
indeed, until a new generation of workers had possession of
the field. The story of the introduction, discussion and final
acceptance of the glacial theory in America is an entertaining
and instructive chapter in the history of science.

The reports of the early state geological surveys, the tran-
sactions of learned societies andthe volumes of Silliman’s Jour-
nal down to about 1850 contain frequent references to “‘diluvial
drift,’ ‘“‘diluvial scratches,” “tremendous currents of water,”
and terms of similar import. The first suggestion of ice as
a contributory agent in the genesis of the drift, in the form of
icebergs or icefloes, was made by Peter Dobson of Connecti-
cut, in a letter to Silliman, + dated November 21, 1825. Mur-

*The writer hopes to insert in the record of Section E for the
next meeting (1899) a notice of any important additions or correc-
tions which are brought to his attention.

tIt is not desirable to encumber these pages with a great number of
bibliographic references. These can be found in chronologic order
under authors’ names in United States Geological Survey Bulletin No.
127— ‘Catalogue and Index of Contributions to North American Geol-
ogy, 1732-1891,” by N. H. Darton. (See “Glaciology,” page 417 and
“Pleistocene,” page 756.) Bulletins Nos. 130 and 135 contain the
bibliography from 1891 to the close of 1&95.

150 The American Geologist. — September, 1898

chison gives to this letter of Dobson the credit of suggesting
to him the iceberg hypothesis, while Edward Hitchcock ob-
tained his similar idea from Sir James Hall of Scotland.

So far as the writer has discovered in print no American
geologist suggested land or glacier ice as a possible cause of
the drift phenomena until 1827. when T. A. Conrad asserted
his belief in such agency in the following words:

“Whence then this immense body of ice which has scattered boulders
over so vast a tract of country, appearing too at an epoch subsequent
to the extinction of the Mastodon and other mammalia, which evi-
dently lived in this region and enjoyed equatorial climate anterior to
the icy period? Nothing can reconcile this apparent contradiction
but the admission of a fall of temperature far below that which prevails
in our day, freezing the enormous lakes of that period and converting
them into immense glaciers, which probably continued undiminished
during a long series of years.”

We cannot, however, regard Conrad’s suggestion as a fair
presentation of the glacial theory. It was made only incident-
ally, as an argument for his hypothesis of epochs of cold cli-
mate, and without any attempt to give a full statement or to
marshall the facts as bearing upon the genesis of the drift. It
is significant, however, as indicating, by the casual way in
which he introduces the argument, that the conception of
great bodies of land ice might not have been, even at that time,
an entirely new idea to American geologists. The work which
then had been prosecuted for some years upon the alpine gla-
ciers was probably not entirely unnoticed by Americans.

The American geologist who first gave a favorable recep-
tion to the glacial theory of Agassiz, as far as printed records
show, was Edward Hitchcock. In his address as retiring pres-
ident at the second annual meeting of the Association of
American Geologists and Naturalists, held at Philadelphia,
April, 1841, he described the characters of the drift and the
various phenomena which we now call glacial with great ac-
curacy and appreciation. After discussing several hypotheses
of the drift he writes as follows:

“But the recent work of Agassiz, entitled ‘Etudes sur les Glaciers,’
gives a new aspect to the subject. . . . . . Henceforth, however,
glacial action must form an important chapter in geology. While
reading this work and the abstracts of some papers by Agassiz, Buck-
land and Lyell, on the evidence of ancient glaciers in Scotland and

Glacial Geology in America —Fairchild. 157

England, I seemed to be acquiring anew geological sense; and |
now look upon our smoothed and striated rocks, our accumulations
of PES and the Zout ensemble of diluvial phenomena with new eyes.’

: I do not mention these difficulties (to which I
might add more) as any strong evidence against this theory. For so
remarkably does it solve most of the phenomena of diluvial action,
that I am constrained to believe its fundamental principles to be
founded in truth.”

In the application of the hypothesis to American drift he
stated his chief difficulties to be: (1) the general southerly di-
rection of the strize and drift transportation over New England
and New York, instead of radiating from the highlands as in
the Alps; (2)the lifting of the erratics from lower to

-higher levels, although for this work he regarded ice as more

efficient than water; and (3) the localized drift masses which
we now call “drumlins.” At that time, with only Alpine gla-
cier phenomena as the foundation of the theory, these were
valid and forcible objections. Indeed his presentation of the
argument for and against glacial agency showed excellent ap-
preciation and grasp of the subject, and to-day can be read
with profit. This is also true of his “Postscript,” discussing
the glacier hypothesis and moraines in the introduction to his
Geology of Massachusetts, 1841.

In these writings Professor Hitchcock seemed to declare his
adherence to the glacial hypothesis, as applied to America,
with as little hesitation and qualification as would be expected
of acarefulman of science in espousing a new theory that an-
tagonized the prevailing belief and prejudice of his fellow
workers. It is evident from subsequent records that his utter-
ances were accepted at the time as committing him to the ac-
ceptance of the theory of Agassiz. But, unfortunately for
truth and for American geology, the circumstances and scien-
tific forces of that time did not allow him to stand upon the ad-
vanced ground he had taken. He was criticised by Murch-
ison, to whom he was attached, and evidently found no support
among his confréres at home. Instead of following Buckland
in support of the glacial theory he went over to the side of
Murchison and Lyell, and the next year at the Boston meet-
ing his elaborate paper on the drift favored the iceberg hypo-
thesis. In 1843 he is quoted in the following words:

158 The American Geologist. September, 1898

“Professor Hitchcock remarked that so disastrous had been his
experience in respect to the glacial theory of Agassiz that he was
almost afraid to say anything more on the subject. . . .. . He
had been supposed to be an advocate for the unmodified glacial theory.
But if he could trust his own consciousness he had never been a
believer in it. . . . . . By this term (glacio-aqueous) he meant
to say that the phenomena of drift were the result of joint action of ice
and water, without saying which of these agents had exerted the
greatest influence. But whether that glacio-aqueous action had been
the result of the enormous accumulation of glaciers, according to
Agassiz, or from floating icebergs . . . . . according to Lyell
and Murchison, or of the upheaval of the Arctic ocean whereby its
aqueo-glacial contents were precipitated southward according to De la
3eche, he had not then made up his mind nor has he yet made it up.”

Professor Hitchcock’s attempt to find some compromise
between the glacial and iceberg theories of the drift was a
failure. He came very near to being a glacialist. If he had
followed his own perception of the truth he would have been
the leader in a great forward movement in geological science,
which, by his defection at the critical moment, was suppressed
for twenty years.

Discussion —The printed accounts of the annual meetings
of the Association of American Geologists and Naturalists
give evidence of a lively interest in the subject of the drift, but
there seems to have been no champion of the discredited gla-
cial hypothesis; or if so he was not thought worthy of record.
There was much difference of opinion as to the agencies of the
drift but all were hostile to the new theory. The brothers
Rogers, with Emmons, Jackson, Nicollet, Redfield, Cout-
huoy and others, lost no opportunity of upholding some form
of the diluvial hypothesis and for ten years no American geo-
logist ventured openly to adopt and proclaim the theory of
Agassiz. Doubtless there were various reasons for this un-
receptive attitude, some of which we can discover. Lyell came
to America in 1841, and in 1842 he attended the third meet-
ing of the geologists, held at Boston, and brought the rein-
forcement of his great reputation to those who favored the
hypothesis of submergence and icebergs, of which he and
Murchison were the great apostles. The supporters of this
theory probably did not clearly understand the genesis of ice-
bergs and did not realize that their hypothesis simply pushed
the glacier area some distance northward. The scientific ob-

Glacial Geology in America.—Fairchild. 159

jections to the glacial origin of the drift were to them conclu-
sive. They were unable to apply to the broad plateaus of
northeastern America the work of local or alpine glaciers.
How could ice flow up hill? The glaciers of the Alps all
moved down the slopes. How could an ice mass move over
even comparatively level tracts? Indeed, Dana did not ans-
wer this difficulty until the 1879 edition of his Manual. The
prevailing southerly direction of the drift movement, with only
minor deflections by mountain masses or great valleys, did not
harmonize with conceptions derived from written descriptions
of the glaciers of the Alps, and they were not prepared to
grasp Agassiz’s idea of a great circumpolar ice sheet. The
very large proportion of water-worn or water-laid materials
in the drift certainly favored aqueous agency.

But there were other antagonistic forces which were not of
a scientific character. Agassiz was a comparative young man
and quite unknown in geology except for his study of glaciers.
How could his opinion weigh against those of the giants in
geology? Another power, which will scarcely appear in the
scientific writings of the time, but which was a great conserva-
tive force, was theological opinion. All hypotheses invoking
water as the drift agency might be harmonized with belief in
the Noachian deluge, but the Bible gave no countenance to
an ice deluge. The ‘“‘diluvium” was an ever present evidence
of the truth of the deluge. To explain it away was little better
than heresy. In these days of liberty of thought it is not pos-
sible for us to realize the repressive power of religious opin-
ion in Puritan New England. Furthermore the diluvial hy-
potheses were unduly deductive, and like all op'nicns not based
on observational or inductive evidence did not readily yield
to the arguments derived from facts. The older geologists had
made up their minds and that settled it. They were also most-
ly committed in print to some form of the diluvial idea. Those
early classics in American geology, the state reports of New
York, Massachusetts and New Hampshire, appeared during
the years 1841-1844, and by generally referring the drift to
aqueous origin helped to fix opinion along diluvial lines. Be-
fore leaving this subject it will be well to state briefly the na-
ture of some of the theories of the drift.

Edward Hitchcock had written the Geology of Massachu-

160 The American Geologist. September, 189%

setts before he became fully acquainted with the theory of
Agassiz. He presents the several hypotheses for the drift, but
rules out glaciers, retains the term “diluvium,” and favors the
idea of waves of translation from the arcticregion. He dis-
plays, however, the openness of mind and keen perception
which led him virtually to adopt the glacial theory upon its
first fair presentation, by distinctly saying that no theory pro-
posed at that time was satisfactory to him. His “Postscript,”
describing glacial phenomena, at the beginning of the volume
was an afterthought, dated 1841.

Lardner Vanuxem in his Geology of the Third New York
District, 1842, referred briefly to the drift, compared the ice-
berg and glacial theories and gave preference to the latter
in some modified form, suggesting the term “local ice” for
“glaciers.”

In the same year Ebenezer Emmons published the Geolo-
gy of the Second New York District. He regarded the ice-
berg theory as fully established. The rock scorings and finer
drift he thought were produced by broad shallow currents or
rivers, at an earlier epoch, while during a later marine sub-
mergence the floating ice had transported the erratics and
coarser drift. Glaciers were entirely ruled out.

W. W. Mather in the Geology of the First New York Dis-
trict, 1843, gave an exhaustive account of the drift. Regard-
ing the glacial theory he had the objections noted by Hitch-
cock. He favored currents of water and floating ice, and
thought that the greater currents were due to a relatively sud-
den collapse of the earth’s crust, producing accelerated veloc-
ity of rotation, and hence quickened oceanic currents.

In the Geology of the Fourth New York District, 1843,
James Hall held views similar to Emmons. He had not seen
the writings of Agassiz, and probably very few American geo-
logists had at that time, but he could not admit glacial agency
as there was no sufficiently elevated land-mass upon the north.

C. T. Jackson, in his Geology of New Hampshire, 1844,
quoted M. de Luc against the glacial theory, even as applied
to Europe, and regarded its application to America as absurd.
He attributed the drift to Arctic waters and ice, they “having
been hurled with great violence over the surface of the north-
ern hemisphere.”

Glacial Geology in America.—Farchid. 161

In a review of Dr. Jackson’s report, T. T. Bouvé wrote as
follows:

“Tn view of all that is known cf the movement of diluvium in this
country we cannot but regard the glacial theory as wholly inadequate
to produce the results met with, and we think with Dr. Jackson that
the grooves on the rocks, if produced by glaciers, should radiate from
our principal mountain ranges and should be more abundant in their
immediate vicinity, while they should be wanting in the level country
and over our extended tablelands!”

The most ardent and extreme champion of De la Beche’s
hypothesis of catastrophic waves or debacles of water was
Prof. H. D. Rogers. The following quotation from his pres-
idential address before the fifth meeting of the Association of
American Geologists, held at Washington, May, 1844, will
give a sufficient idea of this hypothesis. After discussing the
drift at great length and reviewing all the explanation that
had been proposed, he gives the following as his own views:

“If we will conceive, then, a wide expanse of waters. less perhaps
than one thousand feet in depth, dislodged from high northern or
circumpolar basin, by a general lifting of that region of perhaps a
hundred feet, and an equal subsidence of the country south, and
imagine this whole mass converted by earthquake pulsations of the
breadth which such undulations have, into a series of stupendous and
rapid-moving waves of translation, helped on by the still more rapid
flexures of the floor over which they move, and then advert to the
shattering power of the tremendous jar of the earthquake, we shall
have an agent adequate in every way to produce the results we see,
to float the northern ice from its moorings, to rip off, assisted with
its aid, the outcrops of the hardest strata, to grind up and strew wide
their fragments, to scour down the whole rocky floor, and, gathering
energy with resistance, to sweep up the slopes and over the highest
mountains.”

To us at the present time it would seem as if the mere
statement of this hypothesis should have been sufficient for
its own refutation. Certainly it was so far-fetched, calling in
an agency entirely outside the range of human observation
and knowledge, and at the same time denying the competency
of an observable agency which was at that time reproducing
some of the most important drift phenomena, that it seems
unscientific to the last degree. Yet, in 1849, three years after
Agassiz had come to America and long after the detailed ar-
guments for glacial agency had been fully and clearly set be-
fore American readers, professor Rogers wrote:

162 The American Geologist. September, 1898

“V. The diluvial hypothesis, as modified by myself, assumes, not
the submersion of the land but a series of violent elevatory earthquake
movements, in the arctic regions, displacing the arctic waters, with
the ice which bound them, and sending these southward, across the
northern districts of the continents.”’

As early as 1842 the facts concerning the geologic work
of the Alpine glaciers and the arguments for the glacial theory
had been placed before American readers by the republication
in Silliman’s Journal of an excellent article by Charles Mac-
laren. And in the next year of an elaborate review in the same
journal, of James Forbes’ noble book on glaciers left American
geologists with no excuse for lack of general knowledge of
the glacial theory and its reasonable claims.

Late in 1846 Louis Agassiz arrived in America. In 1847
he explored the White Mountains and found evidence of local
glaciers. In 1848 he visited the great lakes and found abun-
dant evidence of continental glaciation. In September of that
year he attended the first meeting of this society, at Philadel-
phia, and described the glacial phenomena about lake Super-
ior, showing the identity of the phenomena in America with
those in Europe. To his personal testimony was added that
of Arnold Guyot and Edmund Desor, who had been colab-
orers with him and had also brought their ample experience
to bear upon the American field. The reception by the older
geologists of this personal and expert evidence was evidently
not of such a character as to encourage Agassiz in further pre-
sentation of the matter. In his book on lake Superior, pub-
lished 1850, he wrote in a somewhat sarcastic vein as follows:

“But such is the prejudice of many geologists that those keen
faculties of distinction and generalization, that power of superior per-
ception and discrimination, which have led them to make such brilliant
discoveries in geology in general, seem to abandon them at once as
soon as they look at the erratics.”

Agassiz did not present another glacial paper before the
Association until 1870, his chief work in the meantime lying
in the domain of zodlogy. However, from about 1850 the ex-
treme diluvial notions were either abandoned or presented
less agressively.

At the second meeting of this Association, in Cambridge,
1849, there was the usual animated discussion of the drift, fol-
lowing papers by H. D. Rogers and Arnold Guyot. An ex-

Glacial Geology in America —Fairchild. 163

tended paper by the latter described the glacial phenomena
in the Alps, and stated that those of the White mountains were
similar. The diluvialists still opposed the glacier theory, even
to the degree of questioning the Alpine observations of Guyot
and Agassiz. James Hall evidently voiced the sentiments of
the younger men when he said, as reported in the discussion:

“In this country there has been a tendency to oppose the glacial
theory because it had been applied for the explanation of diluvial
phenomena. We ought to be ashamed in this country, he said, to
speak with confidence, after so little research, when there had been so
much abroad.”

From this time there are fewer references to the origin of
the drift. A new generation of geologists was taking the place
of the older men and they were freer to accept the new ideas
while not aggressively attacking the prevailing ones. The
writings of the younger men frequently refer to glacial agency
as an admitted fact. Among the contributions to glacial geo-
logy in those earliest years of the science but very few can be
noticed. In 1850 C. B. Adams, at the New Haven meeting of
the Association, read a paper on changes of level in North
America, in which, adopting the hypothesis of Lyell, he sug-
gested the elevation of northern land as sufficient cause of the
ice sheet; also of submergence at the close of the glacial period
to account for the undisputed marine deposits. This hypoth-
esis was elaborated by Dana in his presidential address of 1855,
and placed upon a working basis by three time divisions: (1)
Glacial epoch, with northern elevation of land; (2) Laurentian
epoch, of depression; and (3) Terrace epoch, of moderate
reelevation to present altitude. From this time Dana was the
leader of the glacial forces and the chief exponent of the
theory.

In 1857 Edward Hitchcock published in the Smithsonian
Contributions his extended and valuable paper on Surface
Geology, treating chiefly of the Connecticut valley. He distin-
guished local glacial striz from the general drift striz, and
recognized moraines and other effects of local glaciers. In
1859 C. H. Hitchcock made the same discrimination for New
England in general. The Geology of Vermont, published in
1861, while describing phenomena of local glaciers, attributed
the common drift to icebergs. In 1863 the report of progress

ae The sanieric an Casi Walhg September, 1898

of the ieeeio nical Satan at Ganda’ from its feeaniaes to that
date, contained. a chapter. on surface: geology, written by
Robert Bell, which attributed the drift phenomena to ice and
fully aceepted the’ glacial: theory, even recognizing moraines
in the Ottawa. valley. ARE: ia
.. Acceptance: Tt willbe seen that tite secant anes in Amer-
ica, of. the glacial theory. was ‘by slow:degrees: » It involved the
displacement of. preconceived. deductive hypotheses, and was
opposed by the modified and not unreasonable theory of sub-
mergence and floating :ice, held by: Murchison and Lyell,
which still has’some qualified support. During the decade
from.1850 to 1860-there. was comparatively less discussion
of the drift problem:. Geologists were readjusting: their ideas
and ‘taking new bearings: Then followed the years of the
war of the. Rebellion; when: the thought of Americans was
turned away: from-abstract:science and even the’ meetings of
this Society: were suspended: However, in 1862, the: glacial
theory received two: notable reinforcements: One was, in
England, its public adoption by: Ramsay and his abandon-
ment of the iceberg theory; the other, in America, the publi-
cation of the first edition,of Dana’s Manual of Geology. In
this epoch-making book in geological sctence the whole prob-
lem of the drift was clearly presented. The arguments for and
against both the iceberg and glacial theories were stated with
a logical conclusion in favor of the latter, allowing the work
of icebergs along: the: continental ‘borders ‘and across deep
channels. An unbiased reader could judge for himself of the
merits of the two theories but scarcely fail to accept the con-
clusion of the author. Fhe glactal epoch asa division of Post-
Tertiary time ‘was given its place in the geological time series;
and the’ various elements of the glacial problem were placed
before student and worker so as to be available as a basis for
investigation. The foundation was laid for the construction of
glacial geology, Die the time was not propitious for its com-
pletion. ek
Following the close of the war, interest was renewed in
glaciology, and:two papers by Charles’ Whittelsey, in 1866
and 1867, are worthy of note. . In the latter year_a_masterly
paper by Edward Hungerford, before this Association dis-
cussed the physical conditions and climate of the glacial per-

Glacial Geology in America.—Farchild. 165

iod. He did not-agree with Agassiz’s extreme’ views of great
southern extension of a polar ice-cap; and his moderate con-
clusions are; in general, accepted to-day. -

At this opportune time, 1867, when: ae ore siiiuiled
thought of.the people.was turned into peaceful ways, the re-
vised edition of Dana’s. Manual carried the glacial theory: into
every college of the dand: as the evolutionary product of tive
discussion upon the drift during the fourth of a century.> Hiow;
ever, the theory still: found: some opposition, and ast latetiat
1871 Dana‘said that American geologists: were divided on cthe
iceberg and glacial theories, and he deemed. it mecessaty to
give further proofstagainst:the formen. 23 wcrc diideo on the

When shall. we-say ‘that glacial geology: had its begining
in-America? -The discussion ofthe theory began in 1841 with
the address: of Edward Hitchcock.c ~The acceptance: pinthe
theory by any number of Americans could notchave been \eat's
lier than the personal advocacy-by Agassiz aitd<Guyot im{1848
to 1850. In some: qualified: formsthe theory Iwas Uorbtdass
adopted earlier by a few independent thinkers, as: Conradi&nd
‘Vanuxem. '! The general acceptance of the theory;anad theitlaks
ing ofit a basis ‘for :systematic:. work: veer investigation! wag
probably not before «1867. : ec.ci the theory and the mak-
_ ~The: periods in the eecuict aecsadteameiaeios nva¥
be stated as follows: .. «

Undisputed reign +of ‘diluvial hypothesis—ito A8yarica may
i.- Discussion of the glacial hypothesis—1841 to 1848.

Gradual adoption ofithe glacial theory—+t849 to24866.

Development of pa geology: +1867 eee

oN toe ICE Oe es | he 1806.
lz

Centers’ of Biseltoe The early views oe “thie unity and
simplicity of the ice-cap; ‘following *Agassiz’s extravagant hy-
pothesis of hemispheres of ice) did-mot iong-entlure theittesarof
advancing knowledge: >. The directiduraof istrizxandthertrénd
of peripheral moraines were ,sdon: retognized as tindinating
complexity of growth and of:movement. -tIn: r87¢ Daneacand
gued for multiple centers of radial: movement, and he defetned
the New England: glacier’ to a source. between the Stubay-
rence and Hudson bay: -In' 1879 he saidcthere hath bekrrrnd
ice-cap involving the whole polar region) and recognized also,
that an inclination of the laid surfaceswas hot mecéssdri dor the

"az =ef necessary tor the

166 The American Geologist. September, 1898

movement of the ice-body. In 1880 W J McGee expressed
the view that the polar regions were never more extensively
glaciated than at the present time. Similar views were ex-
pressed by H. Carvill Lewis in 1886, who designated two cen-
ters of ice accumulation and radiation, on the east and west
sides of Hudson Bay, and in 1889 by Robert Bell, the Nestor
of Canadian glacialists.

Dr. G. M. Dawson in 1888 recognized a separate confluent
ice mass in British Columbia between the Coast and Rocky
mountain ranges, and in 18g0 he gave names to two ice bodies,
Cordilleran for the one in British Columbia, and Laurentian
for the eastern one, which he regarded as surrounding Hudson
bay. In 1895 J. B. Tyrell restricted the name Laurentian
(Laurentide) to the mass east of Hudson bay, and gave the
name Keewatin to the body west of Hudson bay. These
three centers (“glacial radiants” of Claypole) were adopted by
professor Chamberlin in his chapter on North American
glaciology in the latest edition of Geikie’s “The Great Ice
Age.” Dr. Dawson thinks the Keewatin and the Laurentian
(Labradorian) centers should be regarded as constituting the
“Laurentide group,” as distinguished from the far-separated
Cordilleran mass.

Migration of Maxima—-The first definite suggestion of
lack of contemporaneity in the growth and culmination of the
glacial centers was made by Robert Chalmers in 1890. From
study of till sheets, boulder trains, etc., in the area of conten-
tion between adjacent ice centers Dr. Dawson, in 1895,
thought there had been a migration of glaciation from the
Cordilleran to the Laurentian plateaus; and in 1896 Mr. Tyrell
made a further refinement by claiming that the Keewatin gla-
cier center had its maximum later than the Cordilleran and
earlier than the Labradorian; and that a fourth center over
Greenland is in existence to-day. This theory of migration
of maximum accumulation receives encouragement from the
results of recent studies of the Alaskan and the Greenland
ice sheets. While the Alaskan glaciers are believed to have
been waning in later time, the Greenland ice cap has probably
increased, at least on the east coast, during several centuries,
or since the time of the Norse colonies.

Thickness. —In 1883 J. C. Smock published an article on

Glacial Geology in America.—Fairchild. 107

the thickness of the ice over New England and the middle
states. Later observations have shown that the thickness of
ice was sufficient to bury the highest mountain peaks within
the ice field. Explorations of the Greenland ice cap have
yielded data concerning the curving slope of the margin of
the ice sheet which seem in the hands of Chamberlin and
-Upham to give a reliable basis for the comparison with ancient
ice sheets. Mr. McGee estimated the thickness in northeast-
ern Iowa as ‘‘500 feet a few miles from the margin, to an in-
definite but not very much greater thickness in the interior of
the ice body.”

Direction of Flow.—Previous to 1879 W J] McGee was
able, by the study of topographic forms of the drift in north-
eastern lowa, to determine the direction of ice ow without
evidence from striz. It is now recognized that drumlins and
eskers are more trustworthy criteria of general direction of ice
movement than the glacial stria, which are more subject to
the effect of local causes. Peripheral moraines are demon-
strations of the direction of flow at the margin of the ice sheet.
By these several criteria it is now demonstrated that the ice
movement followed the trend of the larger depressions and
valleys. As early as 1863 Dana argued, from direction of
striz, for distinct glacial flow in the Connecticut and Hudson
valleys. The very decided localization of movement in the
basins of the Laurentian lakes was shown cartographically by
Chamberlin in 1877.

Lobing of Margin.—This is closely related to the flow in
the longitudinal valleys, and is produced by the concentration
or massing of the marginal ice in such depressions. This
was also shown by Chamberlin in 1877 in his map of terminal
moraines; those of the ice lobes filling the basins of the great
lakes having a conspicuously looped, festooned or crescentric
character. Further study has emphasized the lobate form
of the periphery of the ice sheet, at least during the recessional
phase.

Drifiless Areas. —The surprising and apparently inexplica-
ble phenomenon of an area unaffected by ice action, but
wholly surrounded by glaciated territory, was brought to no-
tice by J. D. Whitney in 1862. Much doubt was felt regard-
ing the nature ard even the existence of this driftless area

168 The American Geologist. September, 189%

until the observations were fully Confirmed by the detailed;
descriptions and illustrations in the elaborated paper by Cham-
berlin-and Salisbury, published in 1886. The explanation is
supposedly: found to lie in the peculiar relation of ice move-
ment through the basins, the ice being diverted from this area.
Until recently this area was thought to be unique but in 1891
professor Salisbury discovered another small: driftless area in
western I[llinois. Le

Transportation. of Drift. ihe precise manner in while the
ice carried its burden of rock debris has been in question. Mr.
Upham has emphasized the amount of enelacial drift.. He
argues that the differential flow of the ice induces ascending
currents which lift the basal. or subglacial drift into. higher
planes of the ice body. . On the other hand professor *Cham-
berlin claims that the continental ice mass never held any: con-
siderable burden of:englacial’drift’'except near the base; and
he finds support for his position in the essentially basal charac-
ter of the debris in the Greenland glaciers. The existence of
ascending currents inthe ordinary flow of the ice-sheet is‘not
admitted by most students of glacial physics. The question is
of some moment in relation to the manner of accumulation of
localized masses of debris, such. as’ ‘drumlins, moraines and
eskers. : idk

As a philosophical. ecereson of the character. and work
of a local ice-body, the writings of W J McGee upon the
glacial phenomena of northeastern Towa deserve special men-
tion. :

-GLACEAL: PERIOD.

Cause.—The cause of the glacial period remains quite as
much a mystery as it was in 1840. A large body of facts has
been collected, but it points in different directions. Every
person has entire liberty. of opinion; most glacialists have no
opinion at all:upon' this’ subject. -Up to 1875 the Lyellian hy-
pothesis of land elevation as a cause of the cold climate and
snow accumulation had the ntajority of adherents. . In Amer-
ica this was proposed by’ C: B: Adams in «1850, and was
adopted by Dana in his presidential address‘of 1855, and was
held by him during his life. It has been the consistent teaching
of the Manual of Geology. Of preglacial elevation of northern
land there is little doubt, but nrany glacialists find reason for

Glacial Geology in America.—Ffairchild. 169

thinking that during the latter part of the glacial period the
land was lower than atpresent, and certainly. was so at the
close. : aN, aD

Croll’s “Climate and Time” presented a plausible as-
tronomical hypothesis, the concurrence of variable elements in
the relation of the earth to the sun affecting alternately thé
north and south polar regions. . For a time this won large as-
sent, but objections soon multiplied. The secular periods of
glaciation apparently required by this hypothesis in preceding
geologic time are quite lacking, although glacial drift deposits
occur as far back as.the Permian. The most serious objec-
tion is the absence of glaciation over vast areas of arctic lands,
as Alaska and Siberias Even >the physical-competency of the
astronomic changes has been questioned, and the hypothesis
has fallen into neglect as the tendency of late is to concentrate
attention on phenomena and more immediate inferences. -

A change in the axis of the earth is a suggestion that finds
few supporters. _ A hypothesis of atmospheric change, a varia-
tion in the amount of the carbon-dioxide content of the at-
mosphere, has recently received the support of professor
Chamberlin. |

The opinion of the majority of geologists. may probably
be fairly stated by saying that the various elements affecting
climate, geographic, atmosphertc and astronomic, are thought
to be so nicely balanced that a comparatively slight change or
maladjustment may produce serious climatic effects.»

Time Divisions.—Professor Dana in 1855 proposed the
tripartite division of the glacial period, correlating with land
oscillation, into (1) the Glacial epoch with high elevation of
land; (2) the Laurentian (Champlain), with depression of the
land; and (3) a transition epoch, called the Terrace, during
which the land rose to its present level and the river terraces
were cut by the enlivened streams. . This scheme was elabor-
ated in the first edition of his Manual, in 1862, and adhered
to with slight changes in all subsequent editions. In the 1879
edition he gave the Terrace epoch a formal place, changing
the name in the last edition to “Recent.” The name “Cham-
plain,” originally given to the marine clays by “dward Hitch-
cock, was substituted for “Laurentian” in the edition of 1867.

While this terminology has been generally used and the

170 The American Geologist ; September, 1898

time divisions adopted in a general way, some modifications
have been thought desirable. It is believed by many that
the Champlain subsidence was far along, perhaps at its maxi-
mum, before the ice sheet retreated. Indeed, Mr. Upham
would make the Champlain only the closing part of the Glacial
epoch. The “Recent”? epoch is now regarded as essentially
a part of the present epoch, and this view is strengthened by
the demonstration, by Mr. Gilbert, that the northward differ-
ential uplift of at least the Laurentian basin is still in progress.

Interglacial Epochs—Dana held firmly to the essential
unity of the Glacial epoch, and in this he was largely followed,
especially by the men who were trained upon the compara-
tively simple, homogeneous drift sheet of the eastern states.
3ut in the broad areas of the west the drift is not so simple.
Early in the study of the region buried soils, peat beds and
other evidences of deglaciation were found intercalated in the
drift, and were noted by Whittlesby, Newberry, Orton, N. H.
Winchell and others. In 1873 Newberry regarded the “For-
est Bed” as marking a distinct deglacial condition in the drift
period. In 1878 McGee described vegetal deposits in the
drift of northeastern Iowa of such depth and areal extent as
to indicate an interglacial epoch, and he discriminated a later
from an earlier till. Subsequently Chamberlin accepted these
conclusions, and in 1882 he discovered the greater southern
extension of the older drift and noted the evidences of a long
intervat between. This idea of the duality or multiplicity of
the glacial epochs met with long-continued opposition, but
was found by the glacialists of the west a good working hypo-
thesis, and evidences in its favor have multiplied.

In 1889 Chamberlin regarded the fringe in Pennsylvania
as the unburied edge of the older drift, and in 1891 Salisbury
described the extra-morainic drift of New Jersey and Penn-
sylvania as the weathered and eroded border of a drift sheet
far older than the moraine-bordered till. This was the first
recognition in the eastern states of multiple drift phenomena,
comparable to that in the western states.

The study was given definiteness and placed on a working
basis by the admirable article of professor Salisbury, in 1893,
on the “Criteria for recognition of distinct glacial epochs.”
The application of these criteria by different workers, particu-

Glacial Geology in America —Farchild. 07

larly Leverett, Coleman and Hershey, has so strongly con-
firmed the view of distinct ice invasions separated by intervals
of deglaciation that this has passed quite beyond the point of
argumentation, and the question now is as to the extent and
duration of the stages of deglaciation, or the relative length
and importance of the glacial and interglacial time divisions.

In 1894, professor Chamberlin presented the whole mat-
ter, in condensed form, in Geikie’s ‘““The Great Ice Age,” and
set the example, subsequently followed by Geikie, of denoting
the several glacial time divisions by geographic names, using
the names of areas where the individual deposits are typical.
In 1895 he gave similar names to the interglacial epochs. The
contemporaneity in Europe and America of the climatic oscil-
lations and the epeirogenic movements, at least in a general
way, seems quite demonstrated by the studies of Chamberlin
and Geikie.

Time Subsequent—A question of great popular interest
concerning glaciation is that of time,—the time in years, espe-
cially since the ice disappeared. Glacialists will in honesty
have to admit that they cannot yet fully satisfy that proper
curiosity. That the time is very brief, judged by geologic time
standards, since the ice sheet finally disappeared from our re-
gion, seems certain. Judging from the freshness of the glacial
scorings and the deposits, 5,000 or 10,000 or 15,000 years is
thought by many glacialists to be a fair estimate of the length
of their exposure. But no reliable chronometer has, yet been
found. Niagara gorge has been regarded as the best time-
piece, butfullerstudy has made the “Niagara Problem” more
complex and uncertain. It seems likely that the volume of
Niagara’s water has varied greatly for long periods, as the
history of the river is intimately connected with that of the
glacial lakes of the upper lake basins. It is admitted that
during the ice retreat the Laurentian basin was lower, as re-
gards sea level, than at present; and was progressively lower
northward and northeastward. It also seems certain that at
the time of the ice removal the waters found lower outlets
eastward from lake Huron than by way of lake Erie, and that
such outflow persisted until the slow differential uplift raised
the northern outlet above the St. Clair outlet. Hence for one,
or probably two, long stages Niagara river carried only the

172 The American Geologist. September, 1898

insignificant drainage of the Erie basin. This argues for greater
length of postglacial time. On the other hand there is a ques-
tion as to the origin of the gorge, whether cut de novo, or in
part reexcavated or enlarged by the modern river. The chief
students of the subject have been Gilbert, Spencer, Upham
and Taylor. Out of the mass of literature two papers must be
noticed: that of Gilbert, “The History of Niagara River,”
1890, which placed the elements of the problem before the
public; and the paper by F. B. Taylor, 1898, “Origin of the
Gorge of the Whirlpool Rapids at Niagara,” which gives the
latest results of the correlation study of Niagara and the glacial
lakes.

The recession of St. Anthony’s Falls in the Mississippi has
also been studied as a measuring rod of postglacial time, espe-
cially by N. H. Winchell, with results concordant with those
of Niagara and other similar studies.

Recently Mr. H. M. Bannister has argued for great dura-
tion of the ice sheet, from data derived from transportation of
far-travelled erratics; and Mr. Taylor finds a great length of
time required to form the moraines of recession in the Erie-
Huron basin laid down by the slow oscillations of the ice front;
the latter paper favoring astronomical forces as a cause of gla-
ciation, at least in part.

The question of glacial time is closely connected with the
problem of glacial cause.

INTERPRETATION OF SPECIAL PHENOMENA.

Drumlins.—These are usually conspicuous topographic
features and frequent references to them, under various de-
scriptive terms, occur in the early literature of the drift. Un-
der the diluvial hypothesis little effort was made to explain
their origin, and Edward Hitchcock found in them an objec-
tion to the glacial theory.

The name “drumlin” was applied in 1866 to similar drift
masses in Ireland by H. M. Close. In America various ap-
pellations were given: by professor Shaler, who was the first
American to write upon them,—‘“drums” and “sow-backs,”
1870; by C. H. Hitchcock, “lenticular hills,’ 1876. The elon-
gated forms of central New York were described in 1882 by
Laurence Johnson as “parallel drift hills,’ and professor

Glacial Geology in America.—Ffairchild. 173

Chamberlin in 1883 called them “mammillary” or ‘elliptical
hills.” The name drumlin was proposed for use in this coun-
try by W. M. Davis, in 1884, and at once adopted.

As nearly all drumlins are composed wholly of till, and
especially so in the superficial part, it was early recognized
that they were an immediate product of ice work, and they
were so referred by Close as early as 1864. In 1872 Kinahan
and Close regarded them as subglacial and constructive, com-
paring them to the longitudinal sand-bars in the bed of a
stream. This view of the genesis of drumlins has been
adopted, in a general way, by most American glacialists.
The suggestion, made by professor Shaler in 1870, that they
may be remnants of an earlier, eroded drift sheet, or that they
represent old moraines remodelled by readvance of ice, as pro-
posed by C. H. Hitchcock, have been quite abandoned. Their
parallelism with the direction of ice movement was first noted
in America by Hitchcock and Upham in 1875. In 1883 pro-
fessor Chamberlin discriminated drumlins from moraines, as
being longitudinal, or axi-radiant with reference to the mov-
ing ice body.

The hypothesis of drumlin origin by the piling of the
ground-moraine by differential pressure and movement of the
overriding ice body, along the peripheral zone where trans-
porting power becomes inadequate to the drift burden, is re-
garded as a plausible and satisfactory explanation. The chief
objection to this is negative, the failure of more uniform dis-
tribution and even the entire absence of drumlins over vast
areas of drift. Another difficulty is physical; a lack of precise
knowledge of the manner in which ground moraine is lifted
in relatively short distances to heights of 100 or 200 feet. Mr.
Upham has attempted to solve this problem by an argument
for the construction of drumlins, and moraines also, by the
lodgment of englacial drift. This difficulty is -less acute,
however, since professor Chamberlin had observed sections
of miniature drumlins beneath the ice foot of the Greenland
glaciers, with the overriding ice moulding itself to the drum-
linoid curve.

Moraines.—The masses of moraine drift were not entirely
overlooked in early writings upon the diluvial phenomena, yet
they were not emphasized since their superior importance and

174 Lhe American Geologist. September, 1898

interest only appear with their recognition as marginal phe-
nomena of the ice sheet. On account of their irregular topo-
graphy and areal distribution they are not so likely to attract
attention as drumlins or even as some eskers, and not until the
glacier theory was so established as to be made the basis of
observation and investigation were moraines discriminated
and mapped. ‘Their systematic study is within the last twen-
ty-five years.

The earliest mention of moraines, by that name, in Ameri-
can geology is believed to occur in the postscript to Edward
Hitchcock’s Geology of Massachusetts. (See above, page 160. )
Appreciating their significance as glacial phenomena he gives
a large space to moraines and notes their occurrence at vari-
ous localities. The closing paragraph is as follows:

“It is possible that the whole of cape Cod is nothing but a vast
terminal moraine, produced by a glacier advancing through Massa-
chusetts bay and scooping out the materials that now form the cape?
In this case the moraines at Plymouth and Truro would form part of
the lateral moraines, and probably most of Nantucket and Martha’s
Vineyard might be regarded as moraines of the same glacier, when it
extended further south.”

The hills of the Long island moraine were described by
Mather in 1843, in his report on the first New York district,
but without recognizing their true character.

In his chapter on surface geology, in the report on the
geological survey of Canada for 1863, Robert Bell described
ridges of drift as resembling moraines, along the Ottawa river,
which was a correct diagnosis. His map of superficial depos-
its, accompanying that report, is believed to be the first map
of Pleistocene deposits published in America with recognition
of glacial agency.

In 1864 J. D. Whitney published a notice of terminal mo-
raines of alpine glaciers in the Sierra Nevada, about Mt. Lyell
and Mt. Dana. In 1866 Whittlesey indicated on his map, in
the Smithsonian Contributions, “morainic knolls” south of
lake Erie, also west of lake Michigan, the latter being the
noted “kettle range,” studied later by Chamberlin, but appar-
ently he did not understand their significance as terminal
drift.

In his report of the Iowa geological survey, 1870, Dr. C.
A. White refers certain ridges, somewhat hesitatingly, to ter-

Glacial Geology in America—Fairchild. 175

minal moraines. Excluding the references by Edward Hitch-
cock, this is probably the earliest notice printed in the United
States of terminal moraines in the open country, as distin-
guished from those of alpine glaciers in the mountain valleys.

In 1871 Mr. Gilbert described the series of recessional mo-
raines in the Maumee valley; and from this time the study of
morainal drift was prosecuted with more confidence.

Probably the earliest positive recognition of the great ter-
minal moraine of the continental ice sheet was made by C. H.
Hitchcock in a paper on the Long island moraine read before
the New York Lyceum of Natural History in 1868, but never
printed. Several years passed before there were any pub-
lished descriptions of the terminal moraine, and it is interesting
to note the comparative suddenness and contemporareity with
which several workers covered the entire line of terminal drift
from Cape Cod to the Missouri. In 1875 G. M. Dawson rec-
ognized the “Missouri Coteau” as marginal glacial debris.
In 1877 T. C. Chamberlin described the Wisconsin kettle mo-
taine and indicated the southern limit of drift from Nebraska
to New York. This was the first definite mapping of mo-
taines in American geology. In the same year George H.
Cook and John C. Smock published their first paper on the
terminal moraine crossing New Jersey, and in 1878 and 1879
Warren Upham published descriptions of the terminal mo-
raine series which he had surveyed from Staten island to cape
Cod. In 1881 H. Carvill Lewis and G. F. Wright traced the
same drift series across Pennsylvania, the results being printed
in 1884. Professor Chamberlin’s classic paper on the “Ter-
minal Moraine of the Second Glacial Epoch” which has been
a basal reference for all subsequent work upon the moraines
about the great lakes, was published in 1883. It will be seen
that within six years, 1877 to 1883, the important terminal
and recessional moraines within the limits of the United States
were located and described; and although the work in prepar-
ation for publication, especially by professor Chamberlin, must
have occupied some years preceding, it is nevertheless a good
example of the saltant character of intellectual progress.

In 1878 professor Chamberlin correlated the cape Cod-
Long island morainal series with the “kettle moraine” belt of
the interior region.

176 The American Geologist. September, 1898

A discrimination between the extreme southern tract of the
drift, in the Mississippi basin} and the more definite morainal
belt of a later ice invasion was made by professor Chamberlin
in 1882. A similar discrimination in Pennsylvania and New
Jersey was made by R. D. Salisbury in 1891.

Against the great debt which American glaciology owes to
European investigation there is something on the credit side.
The skill acquired in the study of American moraines enabled
two American geologists to find similar phenomena in Eur-
ope. H. Carvill Lewis, in 1886, traced terminal moraines in
Great Britain and Ireland, and one year later R. D. Salisbury
did the same thing in Germany, these being the first discovery
of open-country moraines of the massive order of the Euro-
pean ice sheets. These discoveries of European peripheral
moraines were of great importance, as they laid the foundation
for further location of morainal belts and so made possible a
comparison of the marginal oscillations of the ice sheets of
the two continents, by help of which the geologic equivalency
of the successive glacial and interglacial deposits of Europe
and America has been determined.

A peculiarity of the American deposits is the peripheral
moraines common to, and produced by, two opposing or ad-
jacent ice lobes and termed “‘interlobate” by professor Cham-
berlin.

The correlation of moraines of recession with glacial lake
shorelines will be noted below. In the study of the successive
moraine belts between Cincinnati and Mackinac, F. B. Taylor
has reached the conclusion that these moraines were produced
by periodic oscillations of climate, so slow as to be referable
only to some astronomical cause, probably the precession of
the equinoxes. But Croll’s hypothesis is not believed to fur-
nish alone a satisfactory explanation.

As regards the precise manner of morainal accumulation,
especially of the taller hills, there is not entire concordance of
opinion. In several writings Mr. Upham has argued that the
moraines were formed from englacial drift during episodes
of equality of advance and melting, following stages of greater
ablation and concentration of superglacial drift; and that these
conditions were possible only during the warm Champlain
epoch. Other writers deny the existence of any large amount

Glacial Geology in America.—Farchild. i77

of englacial drift, except near the base (see page 168) and re-
gard even the highest moraine hills as due to piling of sub-
glacial or basal drift by the thinner ice edge overriding its own
debris.

Eskers. —The name “osar,” borrowed from European lit-
erature, was applied by Edward Hitchcock to masses of water-
laid drifts as early as 1842, and appears frequently in subse-
quent writings upon the drift. The word was generally used
without close discrimination, however, being applied to irregu-
lar mounds of gravel and sand as well as to ridges. An early
identification was made by C. T. Jackson, in 1843, who said
that the European osars were identical with the “horsebacks”’
of Maine. During subsequent years down to 1880 the word
“kame” was generally employed instead of osar. The name
“serpent kame” was applied by Shaler in 1888, in print.

The term “esker’’ was first used by G. H. Kinahan in 1863,
being applied to gravel ridges in Ireland, but in America it
remained for W J McGee to make, in 1881, the needed differ-
entiation between eskers, applied to elongated ridges of gravel
and sand, and kames, designating sand or gravel deposits of
irregular or morainic topography. Gradually the word esker
has displaced the less convenient word osar, although the lat-
ter has priority.

Since the acceptance of the glacial theory it has generally
been recognized that these ridges of gravel, under whatever
name, were formed by glacial streams. In 1872 N. H. Win-
chell attributed the gravel ridges observed by him in Ohio and
Minnesota to the work of streams in longitudinal crevasses,
and a more definite explanation in America was made by War-
ren Upham in 1876, when he referred those in New Hamp-
shire to glacial rivers, either supraglacial or subglacial.

The genetic distinction between eskers and kames, made
by McGee in 1881, was emphasized and amplified by Cham-
berlin in 1883 and 1884, referring the esker phenomena (using
the term osar) to the class of axi-radiant or longitudinal
stream drift, as distinguished from the peripheral kame de-
posits. That eskers are constructive forms, deposited in the
beds of glacial streams, in comparatively stagnant ice, seems
to be universally admitted. There remains, however, some
lack of unanimity as to the attitude of the streams, whether

178 The American Geologist September, 1898

upon or within or beneath the ice body. In 1884 professor
Shaler gave reasons for believing them to be formed in chan-
nels of subglacial streams. Mr. Upham has regarded the
streams as superglacial after the subglacial channels had be-
come obstructed, or in some cases as flowing in deep ice-
walled canyons, reaching perhaps to the ground. Down to
1890 George H. Stone, in his writings upon the drift phenom-
ena of Maine, regarded the esker streams as mainly supergla-
cial, but in 1893 he thought them subglacial, at least in the
coastal region. In a critical study of the origin of certain
eskers in Massachusetts by W. M. Davis, and in a discussion
of the mechanics of the phenomena by J. B. Woodworth, both
authors conclude that the streams were subglacial; and the
weight of opinion now favors subglacial streams in the rela-
tively stagnant submarginal portions of the ice sheet. The
observations of professor Russell in Alaska and of professor
Chamberlin upon the ice foot in Greenland, give force to this
view. There seems to be no better explanation for the greatly
extended, continuous eskers of uniform cross section, or prism,
which traverse hills and valleys, than that they were formed
in tunnels in or beneath the ice; the streams in many cases be-
ing under hydraulic pressure. But doubtless some of the
broader or shorter, discontinuous, irregular ridges may have
been deposited in other ways, near the ice front. A question
of some importance in this connection is the relative amount
of interglacial or superglacial drift. In an ice body with little
debris above its base only subglacial streams could acquire
great burden.

In northeastern Lowa occur some unique deposits which
may be regarded as allies to eskers. They have been de-
scribed by McGee and named “paha.” ‘These are elongated
ridges of aqueo-glacial material upon the surface, deposited
in canyons in the ice. “The streams were originally super-
glacial, so that the modern drainage is ‘superimposed from
ice, to use Gilbert’s expression; these streams were originally
located by eminences under the ice, which retarded the flow
and developed incipient lobation; and after the streams had
deepened their channels so far as to materially reduce the
thickness of the ice, then the subglacial water was forced to-
ward the same lines, and the superglacial and subglacial flow

Glacial Geology in America.—Fairchild. 179

coincided and eventually formed ice canyons in which the paha
were accumulated.”

Kames.—In an historical way it is difficult to discuss kames
apart from eskers, as in the literature down to 1881 the several
names employed were used quite indifferently and the two
forms of deposits were not discriminated.

Edward Hitchcock in 1847 evidently described areas of
kames under the name of “moraine terrace,’ and admitted
that he was unable to determine their origin.

As stated above (see under eskers) the name was first used
discriminatively by McGee in 1881, and Chamberlin in 1883
and 1884 described them as constructional forms, not ero-
sional, as some writers had thought, and grouped them gene-
tically with water-laid drift, peripheral to the ice body and as-
sociated with terminal moraines.

As to the precise physical conditions under which kames,
kame-areas and kame-moraines were formed there is still some
uncertainty. That they were deposited by glacial streams in
immediate relation to the ice edge is regarded as quite cer-
tain. But were they formed on open ground, or in standing
waters? And were they from subglacial drainage or from
streams higher in the ice sheet? The latter question is partly
dependent upon the amount of interglacial and superglacial
debris. Mr. Upham has favored the latter source of supply,
but from the study of the Greenland glaciers Chamberlin
thinks that both kames and eskers are from basal drift, and
are “products of relatively active, vigorous glaciers.” It
seems that the existing glaciers of Alaska and Greenland sug-
gest subglacial origin of the kame drift, but it is conceivable
that the conditions of the American continental ice sheet may
have been different.

In 1884 professor Shaler presented an argument for the
formation of kames in static water by detritus-burdened sub-
glacial streams issuing from the ice front under hydraulic
pressure. This theory might explain the majority of kame
deposits, which with highly* accentuated topography, seem
more abundant in localities of marine Or lacustrine submer-
gence during the ice recession. But mounds of water-laid
drift are found at various altitudes and such were evidently
formed under different conditions. It might be well to dis-

180 The American Geologist. September, 1898

criminate here and restrict the word kame to the typical sub-
aqueous deposits and find another term for the subaeérial ac-
cumulations.

Kettles —Perhaps less progress has been made in explana-
tion of the hollows or bowls called “Kettles” than of any other
glacial phenomenon. The explanation of their origin made
by Edward Hitchcock in 1841, that they were produced by the
melting of buried masses of ice, is still the common interpreta-
tion of their genesis. In 1859 this idea was adopted by Whit-
tlesey in his paper on the “Drift Cavities or Potash Kettles of
Wisconsin.” In 1877 professor Chamberlin mentioned four
possible causes of Kettles: (1) irregularities of heaping; (2) the
pushing of one drift ridge unconformably against a preceding
one; (3) the incorporation of ice blocks; and (4) under-drain-
age. In 1884 Dana thought the basins in the gravel terraces
of the New Haven region were produced by eddies in the
flowing water; but these have been examined by J. B. Wood-
worth who pronounces them typical ice-block kettles. Those
irregular depressions, sometimes of large size, which occur in
water-laid drift, suggesting the name “pitted plains,” have re-
ceived no other acceptable explanation than that of ice-block
genesis, although still regarded by many geologists as of un-
certain origin.

It seems probable that “kettles” may be of various origin.
Some of those in moraine and kame deposits may be due to
irregular piling of the drift, while others were most certainly
occupied by ice blocks during the deposition of the drift.
Some of those in delta terraces are evidently due to deficient
filling by the capricious action of shore and stream currents.
The larger and deeper ones in river terraces or in deltas, giv-
ing rise to the name “pitted plains” are most probably of ice
block origin.

The literature of the subject is scanty. Among later writ-
ers are Mr. Upham and professor Woodworth. The latter
has endeavored to estimate the size of the ice blocks from a
study of the kettles.

Valley Drift, Terraces——The enormous quantity of water-
laid drift in the stream valleys leading south from the glaciated
areas, as well as within those areas, was the firmest basis for
the diluvial hypothesis of the drift; and the early literature

Glacial Geology in America.—Farchild. 181

contains considerable matter upon the subject. Down to
1857 the most voluminous writer was Edward Hitchcock. As
early as 1833 he explained the Connecticut river terraces by a
down-cutting of the river through beds deposited in higher
stages of flood. In his paper of 1857 he recognized the com-
plexity of forces and thought that the valley terraces were
formed in different ways; those of the Connecticut valley
chiefly by a slow lifting of the land with local changes or shift-
ing of the streams. The recognition of the valley drift of New
England as derived from glacial debris and deposited by glacial
floods was made by Dana in 1855. As early as 1858 M. Tuo-
mey suggested that the Mississippi valley drift was deposited
by floods from the sudden melting of the northern glaciers,
and in 1859 E. B. Andrews correlated the terraces of the
southern Ohio valley with the glacial drift.

Concerning details of the terrace formation in New Eng-
land there have been divergence and changes of opinion. In
the earlier editions of his Manual Dana held that the terrace
drift was accumulated during a time of land depression and
slack drainage, and the terraces excavated during pauses in
the reélevation of the land. But in the edition of 1879 he
admitted that the height of the upper terraces marked the
height of the glacial flood, and that change of land altitude was
not essential; thus granting the early contention of Hitchcock.

Loess——The resemblance of certain superficial deposits
throughout the interior portions of the United States to the
“Loess” of Germany and of China was recognized early in
this century, but the writer is not certain of the earliest sug-
gestion of connection of the deposit with glacial phenomena.
Such suggestion was made as early, at least, as 1866, by Whit-
tlesey, who attributed the “loess-like” deposits of Illinois,
southern Iowa and Missouri to floods from the melting ice
sheet. From that date to the present the numerous writers
upon the loess have been almost unanimous in regarding the
American deposits as aqueous, and as having some relation
to glacial conditions, although there were differences of opin-
ion as to the precise conditions of deposition. One notable
exception to this view was published in 1879 by R. Pumpelly
advocating the eolian origin of much of the Mississippian
loess. A paper by J. E. Todd before this association in 1878

182 The .American Geologist. September, 1898
gave a good summary of the aqueous argument. In 1881
Chamberlain was almost alone in thinking that the loess of
Iowa and Nebraska was partially aqueo-glacial and partially
eolian, in which opinion others now concur.

During the years 1878-1881 McGee discovered that the
Iowan loess was an aqueo-glacial deposit, marginal to the drift
sheet now named “Iowan.” This work was published in 1882.
This idea was subsequently amplified and given with more full-
ness and detail by Chamberlin.

The description by Todd and Bain, in 1895, of six feet of
till, supposed to be of iceberg origin, intercalated in the loess
of Iowa, would help to confirm the theory of fluvio-lacustrine
origin of at least those deposits.

The latest conclusions upon the subject of the loess are
found in two papers of last year, one by J. A. Udden, the other
by Professor Chamberlin, which agree in attributing the Mis-
sissippian loess partially to eolian origin. The paper of Mr.
Udden argues for the atmospheric origin in larger part. Pro-
fessor Chamberlin holds that the loess was originally glacio-
aqueous and only secondarily eolian, the latter in minor part;
in these respects differing from the Asian loess of Richthofen.

Lake. Basins.—Preglacial Drainage——The problem of the
origin of lake basins, especially those of the Laurentian sys-
tem, has been so intimately connected with glacial studies
that the subject should be mentioned.

With the extreme views of glacial erosion that were cur-
rent after the general adoption of the glacial theory of Agassiz
it was but natural to attribute even larger lake basins to the
gouging erosion of the ice sheet. That such is the genesis
of many smaller tarns and lakelets in areas of thin drift is ad-
mitted. Geikie states this emphatically for Scotland, and Bell
for Canada. Twenty years ago Newberry so explained the great
lake basins, with Dana assenting somewhat cautiously. As
late as 1894 professor Tarr thought that the Cayuga basin had
been deepened 450 feet by glacial erosion.

On account of the incidental character of the references to
this matter it is doubtful where credit should be given for the
earlier suggestions of the current views. As early as 1866
Whittlesey recognized that the preglacial topography of the
region of the great lakes was in its broader features the same

Glacial Geology in Americt.—Fairchild. 183

as at present. This was an important observation and gave
a basis for moderate views. In 1881 J. W. Spencer attributed
the great lake basins to subaerial and fluviatile agencies, and
professor Claypole the same. The complexity of their origin
was emphasized by professor Chamberlin in 1883, and this
now seems evident.

In 1863 J. P. Lesley attributed the New York lakes, with
Erie and Huron, to “northward rise of their flogr-rock.”” This
keen inference has been verified by studies of the old shore-
lines. It is now generally believed that the great lakes occupy
preglacial basins of subaerial erosion, modified in some unim-
portant degree by the mechanical abrasion of the ice; and that
the ponding of the water, while possibly due in some extent
to morainal damming, is chiefly due to differential northeast-
ward uplift.

Dr. Newberry, as early as 1862, showed the existence of
ancient river channels in the Erie basin buried under glacial
debris, and proving the higher altitude of the land in pre-
glacial time. In 1869 he predicated the existence of an un-
discovered channel that must have been the preglacial con-
nection of the Huron and Erie basins, and in many subse-
quent writings he discussed the ancient drainage of North
America. Dr. J. W. Spencer subsequently took up this work
in the Laurentian basin with good results, and has endeavored
to map the preglacial drainage of the great lakes.

The studies of Spencer, Carll, Foshay, I. C. White, Salis-
bury, Chamberlin, Leverett and others, indicate that some of
the area, now drained southward by the upper Mississippi,
Ohio and Susquehanna, was in preglacial time probably
drained northward.

Glacial Lakes.—The glacial phenomena receiving the lat-
est serious study are those of ice-dammed water. The sub-
ject has been found of unusual and romantic interest and con-
siderable literature has accumulated, chiefly during the last
decade.

The necessary existence of lakelets or small ephemeral
bodies of water between the ice foot and north-sloping land
surfaces has long been recognized, but it is only in recent years
that the conception has been enlarged to grasp lakes of vast
extent and duration. The possibility of such lakes has been

184 The. American Geologist. September, 1898

questioned, but the facts are so numerous, so easily found and
verified and so clear and incontrovertible that doubt is no
longer possible.

With the approximate determination of the trend of the
retreating ice foot, as shown by the peripheral drift, the history
of the glacial waters becomes possible. The study of glacial
lakes naturally followed the study of moraines. The two
studies are now prosecuted together with advantage, since it
is found that shorelines and outlet channels must frequently
correlate with moraines.

The conspicuous shoreline phenomena about the Lauren-
tian great lakes were early observed by settlers and travellers,
particularly in the basins of Ontario and Erie, and their char-
acter as beaches was understood. Lyell in 1842 regarded
them as marine, but the common explanation and the correct
one, attributed them to fresh waters. They were the subject
of study and printed description by Thomas Roy (1837),
Lyell, Hall, Whittlesey, Newberry, Gilbert, N. H. Winchell
and Klippert before the true cause of the high waters was
understood. Dr. Newberry seems to have been the first one
to recognize the ice barrier as the occasion of the high-level
waters in the Laurentian basin. As early as 1862 he clearly de-
scribed the ice wall of the retreating glacier as forming the
northern shore of the fresh-water inland sea and described the
consequent phenomena. In 1869 he presented the same facts
more definitely and with greater fullness, but apparently he
did not yet clearly realize that the ice wall was the dam or bar-
rier which retained the broad waters at the ancient high level,
suggesting, instead, some change in the attitude of the land.
However, he did recognize the ice barrier in his first vol-
ume on the geology of Ohio, published in 1873; and in the
second volume, 1874, he not only clearly predicated the ice
dam but discussed the whole history of the glacial waters,
from the early primitive stages, in a manner that shows he had
a clear conception of the main facts.

Before this association in 1872, N. H. Winchell suggested
the damming of the Michigan waters upon the north as having
made the ancient Chicago outlet effective; also the blockade
of the St. Lawrence valley as causing the high-level waters in
the Erie basin. The latter suggestion doubtless implied the

Glacial Geology in America.—Fairchild. 185

blocking also of the low divide between the Ontario basin and
Mohawk valley, which is far below the old shorelines. In
the same year, 1872, Winchell suggested that the waters of the
Winnipeg basin (lake Agassiz) had been forced south, through
river Warren, by a glacier barrier. These were probably the
earliest definite localization of glacial waters.

The first mapping of ancient beaches, and the correlation
of those beaches with an abandoned outlet, was by Mr. Gil-
bert, in 1871, in description of the Maumee valley beaches and
the Fort Wayne outlet. Land deformation he supposed was
the cause of the change in water level.

The tracing of the beaches in the Erie basin was done by
Gilbert, Winchell, Klippert and Newberry mostly before 1872.
Newberry’s map of the beaches west of Cleveland, 1874, is the
first map of glacial lake beaches, so recognized.

The earliest systematic work upon the beaches in the On-
tario basin was done by J. W. Spencer and published in 1882
with a theory of marine origin. In 1885 Mr. Gilbert printed a
description of the high beaches upon the southern side of the
Ontario basin and correlated them with an eastward outlet
by the Mohawk-Hudson. The names Warren, Algonquin and
Iroquois were applied by Spencer to the ancient high waters
of the Erie-Huron and the Ontario basins in 1888, but with de-
nial of their glacial character.

The earliest comprehensive account of the glacial lake his-
tory of the Laurentian basin was published by Gilbert in 1899,
with maps, which were the earliest cartographic representa-
tion of glacial lakes. In this admirable paper he showed the
rise of the beaches northeastward, due to the differential uplift
of the region; the fluctuation of level in the basins produced
by the opening of successively lower outlets toward the north
and the progressive tilting of the land throwing back the flow
upon southern outlets; with the final result in the present great
lakes.

For the full confirmation of the theory of glacial dams it
was necessary to prove the actual relation of moraines, as
marking locations of the ice barrier, to the beaches. This
was first done by Frank Leverett in 1892, in the western sec-
tion of the Erie basin; and in 1895 in the southeastern section.
In 1896 F. B. Taylor correlated the beaches and moraines in

186 The American Geologist. September, 1898

southeastern Michigan, thereby finding fhe key to the glacial
lake succession in the Erie-Huron basin. His tracing of sub-
aqueous moraines from highland to highland and the correla- '
tion with old outlets and shorelines leave no chance for fur-
ther doubt of the adequacy of glacier dams.

The largest known glacial lake, and the one most fully de-
scribed, is lake Agassiz. The shoreline phenomena of this
lake were described in part by H. Y. Hind as early as 1859.
The southward outlet to the Mississippi was described by G.
K. Warren in 1868: The glacial character of the waters was
suggested by N. H. Winchell-in 1872 and 1877. The name
“lake Agassiz” was applied by Warren Upham in 1879, who
has immortalized the lake, and himself, by his recent mono-
graph.

Several other investigators have described glacial lake
phenomena in different localities: G. H. Cook, in New Jer-
sey, with later description of his “lake Passaic” by R. D. Salis-
bury and H. B. Kummel; E. W. Claypole in Ohio; C. R. Dry=
er, in Indiana; S. P. Baldwin in the Champlain valley; E. H.
Williams, Jr., in the upper Lehigh valley; I. C. White in the
Monongahela valley; the writer in central-western New York;
and especially F. B. Taylor throughout the larger part of the
area of the great lakes.

The glacial lake studies have developed interesting and
important results concerning crustal movements. The de-
formation of the shorelines gives values for the epeirogenic
differential uplift over the Laurentian and the Winnipeg basins
during postglacial time, of which the full significance may not
yet be developed. An interesting problem now ia process of
solution by Taylor, Gilbert and others is the relation of glacial
lakes in the upper Laurentian basin to the history of the Nia-
gara river and the excavation of the gorge. (See above, pages
171-172.)

EXISTING GLACIERS.

The existence of living glaciers in the United States has
been recognized since about 1870, and it is found that in Ore-
gon and Washington are alpine systems which are in some
respects as interesting and instructive as those of Switzerland.
The glacier fields of Alaska and adjacent Canada are far supe-
rior to those of Europe, and include the only known exam-

Glacial Geology in America —Fairchild. 187

ples of the “piedmont” type, of Russell, the broad and com-
paratively stagnant field, fed by streams of the alpine type.
Excepting the little known and inaccessible Antarctic area,
North America possesses, in Greenland, the only existing ‘‘con-
tinental”’ glacier.

The first recorded observation of glaciers in the United
States was made by members of the Williamson Expedition,
in 1855, as Dr. Newberry stated, in writing many years later,
that some of his party found miniature glaciers at the heads
of streams in the group of Oregon mountains called the Three
Sisters; but no description was published. In 1857 Lieut. A.
VY. IXautz reported the discovery of a living glacier on Mt.
Rainier. In 1868 E. T. Coleman explored Mt. Baker and pub-
lished in the following year a description including the gla-
ciers. The earliest important study made by trained geolo-
gists was upon the glaciers of Mts. Shasta, Hood and Rainier
in 1870, by Clarence King, S. F. Emmons and Arnold Hague.

The first geologist to examine the Alaskan glaciers was W.
P. Blake in 1863, his account being printed in 1867. W. H.
Dall and Marcus Baker studied the glaciers of Yukutat bay in
1874 and named the famous Malaspina glacier. Other ex-
plorers were John Muir, 1878, who discovered Glacier bay
and the glacier subsequently named after him; Dall, the sec-
ond visit, in 1880; G. F. Wright and S. P. Baldwin in 1886;
Lieut. Schwatka and William Libbey in 1886, who gave many
names to the glaciers about Yakutat and Icy bays; H. F. Reid
and H. P. Cushing in 1890; and I. C. Russell in 1890 and 1891.
Professor Russell discriminated and named the “piedmont”
type of glacier in 1891, from his study of the Malaspina. The
Copper river glaciers were noted by Lieut. H. T. Allen in
1887, and were seen by C. W. Hayes and Lieut. Schwatka in
1801.

The Canadian glaciers were first explored in the Selkirk
range by Rev. W. S. Green, in 1888.

The Greenland ice’ foot has long been seen by voyagers,
and has been written upon since 1721. The modern study be-
gan with Nordenskiold’s first exploration, in 1870, and with
Helland’s measurements of the ice movement in 1875. The
public is familiar with the venturesome trips on the Greenland
ice cap by Lieutenant Peary in 1886, 1892, 1894, 1895, and the

188 The American Geologist. September, 1898

trans-Greenland journey of Nansen in 1886. While adding
something to glacial science, the work of these and other ex-
plorers was more particularly along lines of geographic and
meteorologic science. The close geologic study only began with
the work of Chamberlin in 1894. This work has been carried
on by Wright, 1894; Salisbury, 1895; Barton and Tarr, 18096.

In accumulating literature upon the living glaciers of the
continent the papers by H. F. Reid and I. C. Russell, relating
to the physics and phenomena of Alaskan glaciers, deserve
special mention, with those of professor Chamberlin descrip-
tive of the structure and behavior of the Greenland ice. Two
writings of professor Russell of a general or descriptive char-
acter, bring down to date a summary of our knowledge of the
glaciers of the continent; the first on “Existing Glaciers of the
United States,’ 1884, and the second a book of the past year,
entitled, “Glaciers of North America.”

Down to a few years ago our knowledge of glacial physics
was almost entirely derived from European study. However,
the glaciers of the Alps gave but small or unsatisfactory help
toward the explanation of some of the most important phe-
nomena produced by the continental ice sheets, for example,
the general sheet of till, drumlins, and the various aqueo-gla-
cial deposits as eskers, kames, loess. The interpretations were
largely inferential. More has been learned of the structure,
behavior and work of our ancient ice sheets by the study of the
Alaskan glaciers during the last ten years, and especially by
the study of the Greenland ice cap during the last four years,
than by all the study of the Alpine glaciers for the seventy
years since they have been observed.

The North American continent is recognized as the theater
of the greatest display of glacial activity, not in the past only,
but also in the present. It must become the Mecca of the
foreign glacialist. Though much has already been ac-
complished the work in America has only begun, and there is
large opportunity for future investigation.

About 1850 the Agassizian hypothesis became the glacial
theory. Now the glacial geologists understand that the glacial
genesis of the “drift” is no longer a theory but an established
fact. They will do well to cease paying the deference to
doubt, implied in the word “theory,” and abandon its use in

Editorial Comment. 189

connection with the casual relation of the glacial phenomena.
The glacial drift is as much a scientific fact as the volcanic cone
of Vesuvius. The latter is seen in process of construction
just as striz, moraines, etc., are seen in the process of forma-
tion. As well might geologists speak of the oceanic theory
with reference to rock strata as longer to speak of the glacial
theory with reference to glacial deposits.

me) Or UAE COMM BINT’.

THE West CoAsT OF GREENLAND.

In a recent article by David White and Charles Schuchert,
of the U. S. National Museum, published by the Geological
Society of America, the authors come to the following conclu-
sions. The observations were made in the summer of 1897
in connection with the expedition of Lieut. Peary of that year:

(1) The Cretaceous and Tertiary rocks in the région de-
scribed lie everywhere unconformably upon a hilly basement
of old crystallines, chiefly gneiss and diorite (Kaersut, Pag-
torfik, Ekorfat), or upon early Cretaceous or pre-Creta-
ceous (?) basalts (Niakornat, Alinaitsunguak, Atanikerdluk).
The greatest altitude of the sedimentary terranes is at Atani-
kerdluk, 3,040 feet above sealevel. The old basalts are highly
altered and usually occur as breccias (Niakornat, Alinaitsun-
guak).

(2) The prevailing easterly dips of the Lower Cretaceous
along the north side of Nugsuak peninsula, in which the strata
should dip westerly, since it is in that direction that the nigher
and younger beds appear, may be in part explained by fault
compensation, as illustrated at Ujarartorsuak. A certain de-
gree of irregularity of dip, the variable and often strong coast-
ward dips, as well as the low altitude of the Tertiary at its
eastern border on the south side of the peninsula (Atanikerd-
luk), are probably due to inequality in the post-Tertiary
epeirogenic movements.

(3) The sediments appear to have been derived from the
east, since the light-colored sandstones and conglomerates are

190 The American Geologist. September, 1898

most abundant on that side of the sedimentary belt (Sook,
Kaersut), where marine fossils appear to be wanting. At one
of the eastern localities (Ujarartorsuak) fresh-water shells oc-
cur with plants. To the west, dark homogeneous shales with
abundant remains of marine animals predominate.

(4) Sedimentation appears to have been continuous in
some portion of this region throughout Cretaceous and early
Tertiary times, since no marked unconformities or unmistak-
able evidence of interruption of deposition have been seen.
In certain sections, however, there appears to be, either in a
variable thickness of the series or a slight difference of atti-
tude, evidence of movements or erosion prior to the imposi-
tion of the Tertiary basalt cap, though these may be only local
or of minor extent. But in many well exposed sections there
is no local trace of sedimentary discontinuity between the
Mesozoic and Tertiary.

(5) The entire thickness of the clastic deposits is proba-
bly over 3,500 feet. They are divided by Heer into four series,
on the basis of their vegetable contents. Of the lowest of
these, the Kome series, developed on the north coast of the
peninsula, a thickness of probably not over 700 feet is ex-
posed above tide. The discovery of additional dicotyledons
in the Kome series, from which hitherto only Populus pri-
mzeva was known, and which was regarded as Urgonian in
age by Heer, casts serious doubt on the reference of those beds
to so low a stage in the Lower Cretaceous. The flora as a
whole is, however, to be compared with that of the Virginian
Potomac formation, with some, perhaps the upper, portion of
which the Kome series is probably synchronous.

The Atane series, hitherto not positively known on the
north shore of Nugsuak peninsula, is clearly present at Ujarar-
torsuak with characteristic Atane plants. Farther west, at
Kook Angnertunek and Niakornat, the dark homogeneous
shale series probably represents both the Atane and Patoot
members of the Upper Cretaceous, since of the marine organ-
isms found here some are identical with those occurring at
Ata and Patoot, the typical localities for the two divisions of
the Upper Cretaceous. The marine invertebrates from the
Atane series, which Heer correlated by means of fossil plants
with the Cenomanian of Europe, strongly indicate that the

Editorial Comment. IgI

series is to be correlated with the Fort Pierre and Fox Hills
or Montana formation of the western United States. Paleo-
botanically the Atane series is so closely related to the Vine-
yard series of Marthas Vineyard, the Amboy clays of the
Raritan region of New Jersey, or the uppermost Potomac of
Alabama as to furnish strong reason for the belief that the
middle of Heer’s groups is the Greenland contemporary of
the Amboy clays. The Patoot series, which appears litho-
logically and stratigraphically to be inseparable from the
Atane series, contains at the same time many plants common
in the upper part of the Amboy clays, with others allied more
closely to the higher Cretaceous floras, such as that of the
Laramie. The Patoot series may perhaps be safely inter-
preted as constituting a paleontological as well as sedimentary
transition from the Atane series to the Tertiary. The thick-
ness of the Atane and Patoot series (Senonian) is not less than
1,300 feet and may considerably exceed this.

The Tertiary clastics at Atanikerdluk attain a thickness of
not less than 1,500 feet, not including the intruded basalts at
least 200 feet thick. The horizon of most of the plants de-
scribed by Heer as Miocene is assumed to be near the base of
that series, the demarkation of which appears to be purely
arbitrary.* It is more probable that the age of the plants
now generally conceded by paleobotanists to be Oligocene
may even be Eocene instead of Miocene. No remains of
marine animals have as yet been discovered with these plants.

The Tertiary clastic zone appears to be thinner west of
Atanikerdluk, and at Patoot and Atane it is presumably rep-
resented by the upper sandstone horizon 200 to 300 feet in
thickness. At the western end of the peninsula its presence is
established in the occurrence of “Atanikerdluk” plants. On
the north coast east of Niakornat there may be a slight devel-
opment of this zone, and it evidently is represented in the in-
terior east of Kook.

The systematic differentiation of the described plant ma-
terial from the Greenland Cretaceous, by means of which so
important a distinction between the floras of the three series,

luk, assumed by the writers to be the base of the Tertiary at that point,
is the only hypothetical lithological bench mark observed in any
section.

192 The American Geologist. September, 1898

as well as such voluminous local floras, was attained, appears
to have necessitated a refinement in species separation that
seems in many cases to be impracticable if not impossible of
satisfactory recognition.

(6) An apparent angle between the horizontally bedded
Tertiary basalt and the supposed Upper Cretaceous sediments
west of Niakornat may warrant the hypothesis of Tertiary
erosion in that vicinity. On the south coast, at Atane and
Patoot, the Tertiary sediments are thought to be thinner than
at Atanikerdluk, which lends further support to this suppo-
sition.

(7) The entire region of the west coast of Greenland in
which Mesozoic or Tertiary sediments are now found is
capped by a great number of superimposed, approximately
horizontal, non-columnar basalt beds of varying thickness and
of great extent. Frequently 3,000 feet of this basalt cap re-
mains, while at Kilertinguak (6,250 feet above tide) over 4,000
feet is preserved.

In certain regions numerous dikes intersect at varying
angles the Cretaceous, Tertiary, and even the lower portion of
the basalt cap, and are frequently found both forking and in-
tersecting. Intruded basalts are not rare, especially in the
Tertiary. The peridotite intrusive beds, about 350 feet thick,
back of Kaersut are probably of Tertiary age, as are also the
other high intercalated basalts.

At the time of the great elevation of the region, probably
in the late Tertiary, the basalt cap, which, judged by the de-
velopment on Unbekanntes island, may have exceeded 7,000
feet in thickness, most probably extended in an unbroken
sheet from the south of Disko island north to beyond the
Svartenhuk peninsula, a distance of 250 miles.

(8) The dissection of this great basalt sheet, the develop-
ment of the Vaigat, the Umanak fiordal system, the isolation
of Disko—in fact, approximately the present land topography
of this coast—were accomplished at a much greater elevation
during Pleistocene time.

(9) Evidence of post-Pleistocene subsidence, with Arctic
climatic conditions, is found in the presence of recent Arctic
marine shells occurring in terraces at an elevation of from 100
to 150 feet above tide. In the old crystalline region much

Review of Recent Geological Literature. 193

farther south the terracing is said to extend to 300 feet above
tide.

(10) The extent of the more recent uplift is not known,
since the retreat of glaciers, the inundation of ancient dwell-
ing sites, and the records of tide gauges point to present down-
ward movement observable within historical time.

Powe yy Or RECENT GEOLOGICAL
BIE RATURE:

Geological Survey of Georgia. Preliminary report on a part of the
Phosphates and Marts of Georgia. S. W. McCa.ute. (Bulletin No.
5-A. of the Georgia survey publications).

The author prefaces his report by a brief review of the phosphate
deposits of other countries, viz. those of England, Wales, Belgium,
France, Spain, Russia, Germany, Norway, Tunis, Algiers and Canada.
He also sketches the phosphates of South Carolina, Florida and Ten-
nessee. He also notes at some length the different theories that have
been proposed for the origin of important deposits of phosphate of lime.

These deposits in Georgia are in the southern part of the state, and
are probably an extension of those recently exploited in Florida. They
are described in Decatur, Thomas, Brooks, Lowndes, Echols, Cam-
den, Glynn and McIntosh counties. These counties contain more or less
of low grade phosphate, but according to Prof. McCallie, probably not
enough of sufficient purity to encourage an expectation of profitable min-
ing, but quite sufficient to be of great value to the agricultural interests
of the region, and especially in the regeneration of exhausted lands.

N. H. W.

On the Interglactal Submergence of Great Britain. By HENR.
MunTHE. Bulletin of the Geological Institution of the University of
Upsala, Vol. ITI, for 1896-97. pp. 369-411, with map and sections; Upsala,
1898.

During a visit of a few weeks to England and Scotland in the
summer of 1897, the author there continued his examination of the
glacial drift and associated marine deposits, on which he had previ-
ously published important papers from his studies in Sweden and
around the Baltic sea. The interglacial beds specially described in this
paper are in Scotland, comprising (1) sections in the ravines of three
streams near the middle of the west side of the peninsula of Kintyre
(Cantire), and (2) the section at Clava in the Nairn valley, six miles
east of Inverness. These are the most interesting fossiliferous inter-
glacial beds known in the British Isles; and probably the most sig-
nificant investigation of any of their sections has been made by Dr.
Munthe, as here noted, at Cleongart, the most northern of the Kintyre

194 The American Geologist. September, 1898

localities. His collections of the fossils from successive levels of the
Cleongart section demonstrate its marine deposition through the evi-
dence of changes of the fauna due to changes in the temperature and
depth of the sea. It is now made impossible to suppose (as might be-
fore have seemed a tenable hypothesis) that the materials of this de-
posit, together with its organic contents, were washed by drainage
from superglacial or subglacial drift, after having been glacially trans-
ported from the old sea bed east of Kintyre over which this part of the
ice-sheet had advanced.

At Cleongart the shell-bearing deposit is stratified clay, 27 feet
thick, of dark bluish gray color (excepting its upper four feet, which,
nearly like the overlying till, is weathered to a brown or chocolate
color), comparatively free from stones in its upper part, but contain-
ing, throughout its whole thickness, scattered small rounded and an-
gular stones, including rarely one that is glacially striated. Near the
middle is a layer of about six inches of ‘“‘a veritable boulder-clay,” in
which no organic remains occur.

Above the shell-bearing clay, a grassy slope of boulder-clay (till),
which is destitute of fossils, rises 74 feet in a distance of about 150 feet,
to an arable field at the top of the ravine. From that point a boring
(made by a committee of the British Association, whose report is pub-
lished in the Proceedings of the Liverpool Meeting, 1896) went down
76 feet through the till, and was continued in the shelly clay 21 feet
farther, thus proving a considerable southward extension of the strati-
fied clay. Beneath, in the exposed section and the adjacent stream
course, is a bed of sand and gravel, which appears to be of glacial
origin, 11 feet thick, to underlying mica schist.

The top of the Cleongart fossiliferous bed is 178 feet above the sea.
(These figures, and most of the definite measurements preceding and
following, are from the report of the Association committee; while the
descriptions of the section are partly from this report, being supple-
mented by Dr. Munthe’s observations.) About a mile distant to the
south, in the Drumore glen, the top of a similar shelly clay, also there
overlain by till; is 199 feet above the sea; and in the Tangy glen, about
three miles farther south, where the Kintyre interglacial marine fossils
were first detected in 1873, the top of the shelly clay, 13 feet or more
in thickness, is at the altitude of 135 feet, and is overlain by about 30
feet of till.

Forty-five species of mollusca, all of which still live in European
seas, are identified from the Cleongart section, as shown by combining
the lists of Dr. David Robertson, in the Association report, and those
of Dr. Munthe; but the most instructive collections were made by the
latter in carefully washing samples of the clay taken from twelve dif-
ferent levels. The fossils from the lowest accessible part of the bed,
including Cardium gronlandicum, Leda pernula, and Yoldia lenticula,
indicate arctic conditions, nearness of the ice-sheet, and a depth of at
least about 4o meters (130 feet), the depression of the land being
therefore about 300 feet, or more, below its present level. Nearly the
same severe temperature and considerable depth of sea are indicated

—s.

Review of Recent Geological Literature. 195

upward for the next six or seven feet, to a hight of about twelve feet
above the base of the stratified clay, including, at the top of this por-
tion, the layer of till before mentioned, half a foot thick, in which fossils
are wanting. Thence upward, the first fossils noted are arctic and
boreal; but at three feet above the thin till deposit the frequent occur-
rence of Turritella terebra implies a more temperate sea, and this
species, with others of Astarte and Cardium, denote a depth between
20 and 75 feet. Similar mild temperature and moderate depth are
shown for the next six feet vertically. Lastly the temperature of the
sea became again arctic, and its depth appears to have increased again
to at least about 130 feet, denoting a vertical submergence of fully
300 feet.

Throughout this deposit of stratified clay (excepting its inclosed
thin layer of till) foraminifera occur plentifully, but with important
variations in the vertical range of species. Their number in Robert-
son’s list is 83, and in Munthe’s list 112, the number common to both
lists being 59. These, and the ostracoda likewise, afford less informa-
tion than the mollusca concerning the physical conditions of the sea
in which the deposition took place; but they seem to present no evi-
dence of a contradictory character, such as might bring any doubt
against the conclusions before stated.

An earlier report by the same committee of the British Associa-
tion, published in 1893, giving details of their examination of the
Clava section, is discussed by Dr. Munthe in the last nine pages of his
paper. This report, and later articles on the same subject by Mr.
Dugald Bell, a member of the committee, were noticed, with full notes
of the section, by the present reviewer in the American Geologist for
January, 1896 (vol. xvii, pp. 45-47), with approval of the minority re-
port of that committee (by Dugald Bell and Prof. Percy F. Kendall),
in which the Clava clay and its shells, occurring at the altitude of 487
to 503 feet above the sea, are supposed to have been supplied from an
ice-sheet that had eroded preglacial marine beds from the basin of
Loch Ness (now about 50 feet above the sea and 774 feet deep), de-
positing the Clava strata in a glacial lakelet held temporarily in a nook
of the Nairn valley by a barrier of ice which later advanced again,
forming the overlying till. From this opinion I yet see no suf-
ficient reason to recede, although Prof. James Geikie, in “The Great
Ice Age” (third ed., 1894, pp. 139-143, 155), and Dr. Munthe, in this
paper, strenuously argue for the marine deposition of the fossiliferous
Clava bed. Perhaps the most noteworthy objection to their view
which can be drawn from the Clava fossils is the occurrence together
there, in considerable numbers, of Litorina litorea, a species whose
habitat is limited to shores and very shallow water, and other species,
as Leda pernula and Natica groénlandica, which are unknown as shore
species but live in depths of 20 to 50 fathoms or more. The assemblage
of fossils at Clava, including 23 species of mollusca, seems to me most
accordant with their reference to glacial transportation, while the ab-
sence of marine beds at similar altitudes elsewhere throughout the |
British Isles further enforces the same explanation.

190 The American Geologist. September, 1898

Dr. Munthe errs in his supposition (following the majority report
of the committee) that the transportation of the Clava strata must be
thought to have been en masse, as a part of the old sea bed on the
site of Loch Ness removed bodily by the ice sheet, carried probably
ten or fifteen miles or more, and laid down bodily in a horizontal posi-
tion under the 43 feet of till, which there forms the surface. Instead,
the materials of the Clava beds and their included fossils are probably
modified drift washed by drainage from the englacial and finally super-
glacial drift of this part of the waning Scottish ice-sheet. In his final
paragraph, Dr. Munthe takes occasion to disclaim any intention of at-
tributing the glacially transported shelly beds of Moel Tryfan and other
high level localities in northern Wales, northwestern England, eastern
Ireland, and southwestern Scotland, to a marine origin. These beds
of shell-bearing modified drift, sometimes of great extent and thick-
ness, and frequently overlain by till, occurring up to the altitude of
1,300 feet above the sea, appear to me referable to nearly the same
processes as the stratified beds of clay, sand, and gravel, under the
Clava till.

From the moderate temperature of the sea at Cleongart during a
part of the time of formation of its stratified clay, Dr. Munthe infers
that Britain had then a long interglacial epoch, with a climate nearly
the same as to-day. On the other hand, from a consideration of the
conditions of climate, fauna, and flora, adjoining and upon the Malas-
pina ice-sheet in Alaska, it may, as I believe, be more probably sup-
posed that only a short retreat and perhaps only a short re-advance
of the ice-sheet, not long separated in time, were sufficient to permit
the marine beds of Kintyre to be formed and to become enveloped by
their covering of till. WwW. U.

Geological Survey of Georgia. Preliminary report on a part of the
water-powers of Georgia. Compiled from notes of C. C. ANDERSON
and other sources by B. M. HALL. (Bulletin 3-A. of the publications of
the Geological Survey of Georgia).

Mr. Anderson did this work under appointment while Dr. J. W.
Spencer was state geologist, and more recently it has been extended by
Mr. Hall, under the direction of state geologist Yeates, in connection
with the hydrographical work of the United States Geological Survey.
The report comprises a great amount of accurate details respecting the
surface drainage of the state, each of the principal rivers having been
examined at the location of the chief water-powers. The tables give
the cubic feet of flowage per second, the fall in feet, the length of the
shoal, the horse power and other general information. Other tables spe-
cify the amount and kind of improvement, number of milis, horse power
used, elevations above the sea at railroad stations and the results of
daily gauging of several streams during two or three years. As an eco-
nomical report it is very valuable, for water power is increasing in value,
because of its easy transmission as electricity. We wish to commend
especially the excellent index, for no such report should be issued with-
out an index, but we cannot approve the peculiar and copious use of
commas which punctuate the text. N. H. W.

yy ol

Authors’ Catalogue. 197

MeN reatiY AUTHORS CATALOGU E
oF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Adams, G. I.

A geological reconnoisance in Grant, Garfield and Woods counties,
Oklahoma. (Kansas Univ. Quarterly, vol. 7, ser. A, pp. 121-124, pls.
11-12, July 1808.)

Agassiz, Alexander.

The Tertiary elevated limestone reefs of Fiji. (Am. Jour. Sci., ser.
4, vol. 6, pp. 165-167, Aug. 1808.)

Aguilar, Rafael. .
Bibliograféa geolégica y minera de la republica Mexicana, (In-

stituto Geologico de Mexico, pp. x and 159, Mexico, 1808.)

Baur, George.
[Sketch of, by O. P. Hay.] (Science, new ser., vol. 8, pp. 68-71,

July 15, 1808.)

Blake, W. P.

Remains of a species of Bos in the Quaternary of Arizona. (Am.
Geol., vol. 22, pp. 65-72, Aug. 1808.)

Bolton, Herbert.

The Lancashire coal field. (Trans. N. Y. Acad. Sci., vol. 16, pp.
224-251, 1808.)
Branner, J. C.

On the origin of novaculites and related rocks. (Jour. Geol., vol.
6, pp. 368-371, May-June 1808.)
Calvin, Samuel.

Contribution to “A symposium on the classification and nomen-
clature of geologic time-divisions.” (Jour. Geol., vol. 6, pp. 352-355,
May-June 1808.)

Gase; E. CG.

The development and geological relations of the vertebrates. Prt.
I. The fishes. (Jour. Geol., vol. 6, pp. 393-416, May-June 1808.)

Chamberlin, T. C.

A supplementary hypothesis respecting the origin of the loess of
the Mississippi valley. [Abstract.] (Proc. A. A. A. S., vol. 46, pp.
204-205, June 1808.)

Clark, W..B:

Contribution to cA symposium on the classification and nomen-
clature of geologic time-divisions.” (Jour. Geol., vol. 6, pp. 340-342,
May-June 1808.)

*This list includes titles of articles received up to the 20th of the preceding
month, including general geology, physiography, paleontology, petrology and
mineralogy. .

198 The American Geologist. September, 1898

Clements, J. M.

A study of some examples of rock variation. (Jour. Geol., vol. 6,
pp. 372-392, May-June 1808.)
iCope Ee; Ds

Edward Drinker Cope, naturalist—A chapter in the history of

science. By Theodore Gill, (Proc. A. A. A. S:, vol. 46, pp: a-9a,
June 1808.)

Dean, Bashford.

Note on the ventral armoring of Dinichthys. (Trans. N. Y. Acad.
Sci., vol. 16, pp. 57-61, 1898.)
Dean, Bashford.

On a new species of Edestus, E. lecontei, from Nevada. (Trans.
N. Y. Acad. Sci., vol. 16, pp. 61-60, 1898.)

Derby, O. A.
Notes on Arkansas novaculite. (Jour. Geol., vol. 6, pp. 366-368,
May-June 1808.)
Eastman, C. R.
Dentition of Devonian Ptyctodontide. (Am. Nat., vol. 32, pp.
473-488, July 1808.)
Eastman, C. R.

On remains of Struthiolithus chersonensis from northern China,
with remarks on the distribution of struthious birds. (Bull. Mus.
Comp. Zool., vol. 32, no. 7, pp. 127-144, I pl., Aug. 1808.)

Eaton, G. F.

The prehistoric fauna of Block island, as indicated by its ancient
shell-heaps. (Am. Jour. Sci., ser. 4, vol. 6, pp. 137-159, pls. 2-3, Aug.
1808. )

Foote, W. M.

Note on the occurrence of native lead with roeblingite, native cop-
per, and other minerals at Franklin Furnace, N. J. (Am. Jour. Sci.,
ser. 4, vol. 6, pp. 187-188, Aug. 1808.)

Gannett, Henry.

Physiographic types. (Topographic Atlas of the U. S., folio 1,
4 pp., 10 maps, 1898.)
Gannett, Henry.

Geographic work of the general government. (Nat. Geog. Mag.,
vol. 9, pp. 329-338, July 1808.)

GilbereiGlak:

Contribution to “A symposium on the classification and nomen-
clature of geologic time-divisions.”’ (Jour. Geol., vol. 6, pp. 338-340,
May-June 1808.)

Gilbert, G. K.

Origin of the physical features of the United States. (Nat. Geog.
Mag., vol. 9, pp. 308-317, pls. 8-9, July 1808.)

Authors Catalogue. 199

Gilbert. J: Z.

On the skull of Xerobates (?) undata Cope. (Kansas Uniy. Quar-
terly, vol. 7, ser. A, pp. 143-148, July 1898.)
Gill, Theodore.

Edward Drinker Cope, naturalist—A chapter in the history of
science. (Proc. A. A. A. S., vol. 46, pp. 1-30, June 1898.)
Hay, O. P.

George Baur. (Science, new ser., vol. 8, pp. 68-71, July 15, 1808.) °

Hershey, O. H.

Notes on the geology of Jamaica. (Science, new ser., vol. 8, pp.
154-155, Aug. 5; 1898.)
Hershey, O. H. ,

Raised shoe-lines on cape Maysi, Cuba. (Science, new ser., vol. 8,
pp. 179-180, Aug. 12, 18908.)
Hollick, Arthur.

Geological notes. Long island and Block island. (Trans. N. Y.
Acad. Sci., vol. 16, pp. 9-18, 1808.)
Hollick, Arthur.

The Cretaceous clay marl exposure at Cliffwood, N. J. (Trans.
N. Y. Acad. Sci., vol. 16, pp. 124-136, pls. 11-14, 1808.)
Hollick, Arthur.

Appendix [to “A new investigation of man’s antiquity at Trenton”’
by H.C. Mercer]. [Abstract.] (Proc. A. A. A. S., vol. 46, pp. 378-
380, June 1808.)
Holmes, W. H.

Primitive man in the Delaware valley. [Abstract.] (Proc. A. A. A,
S., voi. 46, pp. 364-370, June 1808.)
Kemp, J. F.

The glacial or post-glacial diversion of the Bronx river from its
old channel. (Trans. N. Y. Acad. Sci., vol. 16, pp. 18-24, 1808.)
Keyes, C. R.

Contribution to “A symposium on the classification and nomen-
clature of geologic time-divisions.” (Jour. Geol., vol. 6. pp. 347-352,
May-June 1808.)

Keyes, C. R.

Probable stratigraphical equivalents of the Coal Measures of Arkan-
sas. (Jour. Geol., vol. 6, pp. 356-365, May-June 1808.)
Keyes, C. R.

Remarks on the classification of the Mississippian series. (Am.
Geol., vol. 22, pp. ro8-113, Aug. 1808.)
Knapp, G. N.

On the implement-bearing sand deposits at Trenton, N. J. [Ab-
stract.| (Proc. A. A. A. S., vol. 46, p. 350, June 1898.)
Kummel, H. B.

The age of the artifact-bearing sand at Trenton. [Abstract.] (Proc.
A. A. A. S., vol. 46, pp. 348-350, June 1808.)

200 The American Geologist. September, 1898

LeConte, Joseph.

Contribution to “A symposium on the classification and nomen-
clature of geologic time-divisions.” (Jour. Geol., vol. 6. pp. 337-338
May-June 1808.)

Marsh, O. C.

The Jurassic formation on the Atlantic coast—Supplement. (Am.
Jour. Sci., ser. 4, vol. 6, pp. 105-115, Aug. 1898.)

“Marsh; O-G:

The Jurassic formation of the Atlantic coast.—Supplement. (Sci-
ence, new ser., vol. 8, pp. 145-154, Aug. 5, 1808.)

Matthew, G. F.

Recent, discoveries in the St. John group, No. 2. (Bull. Nat. Hist.
Soc. of New Brunswick, vol. 16, pp. 32-43, 1808.)
McGee, W J

American geographic education. (Nat. Geog. Mag., vol. 9, pp.
305-307, July 1898.)

McGee, W J

Geographic development of the district of Columbia. (Nat. Geog.
Mag., vol. 9, pp. 317-323, July 1898.)
Mercer, H. C.

A new investigation of man’s antiquity at Trenton. [Abstract.]
(Proc. A. A. A. S., vol. 46, pp. 370-378, June 1808.)

Merrill, F. J. H.

The geology of the crystalline rocks of southeastern New York.
(soth Ann. Rept. N. Y. State Museum, vol. 1, pp. 21-31, pls. 1-5,
1808. )

Merrill, F. J. H.

The origin of the serpentines in the vicinity of New York. (soth
Ann. Rept. N. Y. State Museum, vol. 1, pp. 32-44, pls. 6-8, 1808.)
Merrill, F. J. H.

Preliminary list of public geological and mineralogical collections
in the United States and Canada. (soth Ann. Rept. N. Y. State
Museum, vol. 1, pp. 45-74, 1808.)

Miller, A. M.

The hypothesis of a Cincinnati Silurian island. (Am. Geol., vol. 22,
pp. 78-85, Aug. 1808.)
Moses, A. J.

Some new appliances and methods for the study of crystals. (Trans.
N. Y. Acad. Sci., vol. 16, pp. 45-57, 1808.)
Newland, D. H.

Notes on the eclogite of the Bavarian Fichtelgebirge. (Trans. N.
Y. Acad. Sci., vol 16. pp. 24-29, 1898.)
Nicholas, F. C.

The mountains and Tertiary valleys of eastern Colombia. (Trans.
N. Y. Acad. Sci., vol. 16, pp. 166-181, pl. 15, 1808.)

2? * a

Authors’ Catalogue. 201

Ordonez, Ezequiel.
Note sur les gisements d’or du Mexique. (Mem. de la Sociedad
““Alzate” de Mexico, t. II, pp. 217-240, 1898.)

Osborn, H. F.

Wasatch and Bridger beds in the Huerfano lake basin. [Ab-
stract.] (Proc. A. A. A. S., vol. 46, pp. 205-206, June 1808.)

Pench, Albrecht.

Changes of level in the glacial formations of the Alps. [Abstract.]
(Proc. A. A. A. S., vol. 46, pp. 203-204, June 1808.)

Putnam, F. W.

Early man of the Delaware valley. [Abstract.] (Proc. A. A. A.
S., vol. 46, pp. 344-348, June 1808.)

Rice, W. N.

A suggestion in regard to the theory of volcanoes. [Abstract.]
(Proc. A. A. A. S., vol. 46, pp. 199-200, June 1808.) -

Ries, Heinrich.

Note on a beryl crystal from New York city. (Trans. N. Y.
Acad. Sci., vol. 16, pp. 329-330, 1808.)
Ruedemann, R.

The discovery of a sessile Conularia. (15th Ann. Rept. State Geol.
of N. Y., pp. 699-728, pls. 1-4.)
Salisbury, R. D.

On the origin and age of the relic-bearing sand at Trenton, N. J.
[Abstract.] (Proc. A. A.A. S., vol. 46, pp. 350-355, June 1898.)

Stevenson, J. J.

Notes on the geology of the Bermudas. (Trans. N. Y. Acad. Sci.,
vol. 16, pp. 96-124, pls. 8-10, 1898.)
Taylor, F. B.

Some features of the recent geology around Detroit. [Abstract.]
(Proc. A. A. A. S., vol. 46, pp. 201-202, June 18098.)

Upham, Warren.

Fjords and submerged valleys of Europe. (Am. Geol., vol. 22, pp.
ror-108, Aug. 1808.)

Wadsworth, M. E.

The origin and mode of occurrence of the lake Superior copper-
deposits. (Trans. Am. Inst. Min. Eng., Lake Superior meeting, July,
1897; 28 pp.)

Wadsworth, M. E.

[Note on zirkelite.] (Jour. Geol., vol. 6, pp. 417-418, May-June
1808. )

Warren, C. H.

Mineralogical notes. (Am. Jour. Sci., ser. 4, vol. 6, pp. 116-124,
Aug 1808.)

Washington, H. S.

Sélvsbergite and tinguaite from Essex county, Mass. (Am. Jour.
Sci., ser. 4, vol. 6, pp. 176-187, Aug. 1808.)

202 Lhe American Geologist. September, 1898

Wieesvoran 1s [be

Weathering of diabase near Chatham, Virginia. (Am. Geol., vol.
22, pp. 85-101, Aug. 1808.)

Weller, Stuart.

The Batesville sandstone of Arkansas. (Trans, N. Y. Acad. Sci.,
vol. 16, pp. 251-282, pls. 19-21, 1808.)

White; I. C.

The Pittsburg coal bed. (Proc. A. A. A.\S., vol. 46, pp. 187-198,
June 1808.)

Winittiela sin i.

Observations on the genus Barrettia. [Abstract.] (Proc. A. A.
A. S.,' vol. 46, p. 200, June 1808.)

Willis, Bailey.
Contribution to ‘““A symposium on the classification and nomen-

clature of geologic time-divisions.”” (Jour. Geol., vol. 6, pp. 345-347,
May-June 1808.)

Williston, S. W.

Contribution to ‘‘A symposium on the classification and nomen-
clature of geologic time-divisions.” (Jour. Geol., vol. 6, pp. 342-345,
May-June 1808.)

Williston, S. W.
The sacrum of Morosaurus. (Kansas Univ. Quarterly, vol. 7,ser.
A, pp. 173-175, July 1898.)

Williston, S. W.

Miocene edentates. (Science, new ser., vol. 8, p. 132, July 20,
1808.)

Wilson, Thomas.

Investigation in the sand-pits of the Lalor field, near Trenton, New
Jersey. [Abstract.] (Proc. A. A. A. 5S., vol. 46, pp. 381-383, June
1808. )

Winchell, N. H.

The significance of the fragmental eruptive debris at Taylor’s Falls,
Minn. (Am. Geol., vol. 22, pp. 72-78, Aug. 1898.)

Wolff, J. E.

Occurrence of native copper at Franklin Furnace, New Jersey.
(Proc. Am. Acad. Arts and Sci., vol 33, pp. 429-430, June 1808.)

Wolff, J. E.

Exhibition and preliminary account of a collection of microphoto-
graphs of snow crystals, made by W. A. Bentley. (Proc. Am. Acad.
Arts and Sci., vol. 33, pp. 431-432, June 1808.)

Wright, G. F.

Special explorations in the implement-bearing deposits on the Lalor
farm, Irenton, N. J. [Abstract.] (Proc) A: Ay AS Szavol 46; pp:
355-304, June 1898.)

viele

AMERICAN GEOLOGIST.
Vor. XXII. OCTOBER, 1808: No. 4

GLACIAL PHENOMENA IN OKANOGAN
COUNTY, WASHINGTON.

By WiLu1AmM L. DAwson.

In taking up the study of this great mountain county, it

"seems necessary to state that no systematic work, apart from

that incident to mining operations, has ever been carried on
here except that done last year, the results of which are not
published yet. Hence this paper can only record scattering
observations and a few inferences drawn from them in this
large and little explored field. Mr. Bailey Willis in 1887
took a hasty survey of the facts in the northern ‘part of the
county and along the Columbia river, publishing them briefly
in his “Changes in River Courses in Washington Territory
Due to Glaciation.” (Bull. No. 40, U. S. Geol. Surv.) Israel
Cook Russell, in the employ of the United States geological
survey, visited the region about Chelan during the summer
of ’92, and makes some notes in Bulletin No. 108 (U. S. Geol.
Sury.), entitled “A Geological Reconnoisance in Central
Washington.” It is to him that I am indebted for many of
the facts in northern Douglas county, which need to be re-
ferred to in order to make our present subject intelligible. It
was the writer’s privilege to spend some fourteen months in
Okanogan county, from June, 1895, to August, 1896. With
headquarters at Chelan, tours were made through all the prin-
cipal valleys, and three or four expeditions were made in ad-
dition to the high mountains about the head of lake Chelan.
The Indian reservation, embracing all the land east of the
Okanogan river, was not visited.

204 The American Geologist. October, 1898

With an area nearly equal to that of New Jersey, Okan-
ogan county may be characterized as a very mountainous re-
gion. Proceeding from the Cascade spurs and foothills, whose
bases the Columbia river washes, throughout the course of
its “big bend” at an altitude of only 600 or 700 feet, the county
rises rapidly to the west and north, culminating in an alpine
region on the west and north-west, which abounds in glacier-
scored peaks and bleak aiguilles ranging in hight to 10,000
feet. The mountains being composed almost exclusively of
crystalline rocks, the scenery is bold and rugged in the ex-
treme.

The drainage is effected by five principal streams which
flow south-east or south to join the Columbia river. Of
these perhaps the oldest in point of origin, but certainly the
newest in its immediate surroundings is the Chelan river,
which drains the lake of the same name. In width a river, but
in depth exceeding any of its kind yet measured in North
America, lake Chelan winds for 60 miles between precipitous
mountains, whose bases meet at least 1500 feet below. Start-
ing from the head of the lake at an altitude of 970 feet, the
valley is continued for 30 miles into the heart of the highest
Alps and drained into the lake by the Stehekin river. Rising
in a chain of lakes in British Columbia, the Okanogan river
passes through the county with a broad valley, in a course al-
most due south. With reference to its present conditions, it
is to be reckoned one of the oldest streams in eastern Wash-
ington, since with the help of a little “lining up,” it can be
navigated to its head in Okanogan lake. It meanders along
a valley floor which is often a mile in width, and this is greatly
augmented in places by the flat-topped terraces, of which I
shall speak later. Midway between these two streams lies the
Methow river, a rapid, treacherous stream which runs for a
hundred miles or so wholly within the limits of the county.
A smaller stream, the Entiat, parallels lake Chelan, which lies
to the eastward, in a narrow valley; while the Wenatchee river
bounds the county on the south-west.

Of these rivers nothing more need be said until we come
to the consideration of glacial phenomena. But the pre-
glacial course of the Columbia river, which is also the present
course, needs to be accounted for. It can be done by refer-

Glacial Phenomena in Washington — Dawson. 205

ence to the country rocks. The rocks of the great Cascade
upheaval, so far as now observable in Okanogan county, west
of the Okanogan river, are almost entirely crystalline. These
rocks compose the west bank of the Columbia™ river from
Wenatchee to the mouth of the Okanogan. The east bank,
on the contrary, throughout this course, presents an un-
broken escarpment of basalt rising 2000 feet high, which ter-
minates the big bend plateau on the west. This is the edge of
the lava sheet; and although the crystalline rocks do at places
crop out from beneath on the east bank, they are always cov-
ered thickly with the basalt capping. The river, whose former,
more direct course lay far to the eastward, was pushed over
against the granite by the advancing lava flood, and its future
course was prescribed by the western limits of the lava; and,
as Bailey Willis has well pointed out, the course from old
Ft. Spokane to the mouth of the Okanogan was determined
by the resultant line of depression between the north-bound
flow of the Big Bend region, and the south-bound flow, which
covers the present Colville Indian reservation.

Then as to its minor topographical features: we find in
this county, and especially in the lower mountain ranges, a
number of peculiar valleys, deep and narrow, called coulées
“commonly pronounced “cool'ies.” This name is applied to
such valleys, whether short or extensive, as are unoccupied,
or at least not adequately occupied by running water, and
have comparatively level floors. Toat’s coulée, with its de-
pendencies in the northern part of the county; Antoine coulée,
from the Methow to the Columbia; Knapp’s and Navarre’s
coulées, which cut through the range between lake Chelan and
the Columbia, may be cited as examples. The problem of
coulée formation offers one of the most inviting subjects
which we shall attempt to discuss in this paper.

Scarcely less noteworthy features of this region are the
terraces which line the principal streams. Those along the
Columbia river are about 300 feet above the stream, and at
favorable points along the river present a surface of several
square miles. The Okanogan river, likewise, is terraced
throughout its length. The terraces of the more rapid streams,
owing to the varied character of their gorges, are more ir-
regular and infrequent.

206 The American Geologist. October, 1898

Lit TLE BEND

OF THE

COLUMBIA.
CONTOUR INTERVAL IS QSFT. EXCEPT
ON TERRACE & MOUNTAIN WHERE SOFT /,

ASSUMED DATUM IS HIGH WATER
LINE OF COLUMBIA AT G5OFT

Diagram No. 1.

Any more detailed description of the topographic features
would anticipate points that I shall hope to bring out in con-
sidering the phenomena in connection with the glacial period.
The evidence of ice action in Okanogan county is most pro-
nounced. Indeed, one has only to note the fresh appearance
of terminal moraines, kettle-holes and terraces, together with
the occurrence of glaciers by the score on the western ranges,
to be convinced that the ice age has retreated none too soon.
Although the glaciation of this region was not effected by a
general ice-sheet, it is because the work was accomplished by
a local and somewhat restricted action, that the results pre-
sent certain unique features. We should expect that in the
several phases of advance and retreat the glaciers would be
largely obedient to the conditions imposed by the previous
valleys of erosion. And furthermore, although we should
concede a general condition of moisture and precipitation
throughout the region, the varying hights of the mountains
and the differing widths of the valleys would principally de-
termine the lower limits of the advancing glaciers. Hence
we are to look for no regular ice-sheet margin, but to remem-
ber that each individual glacier will halt or deploy upon the
plain in a manner depending on the size of its area of accumu-
lation, its distance, and gradient from the divide.

Glacial Phenomena in Washington.—Dawson. 207

Three such glaciers swept down the Chelan, Methow, and
Okanogan valleys, respectively. Of these we may well be-
lieve that the Chelan glacier, both on account of the narrow-
ness of its valley and the hight of its mountains, was the first
to reach the Columbia river. In doing so, it forced out the
waters of the pre-glacial lake Chelan, which must have existed
at a level some 400 feet below the present one, as a lateral
reservoir of the Columbia river. Upon reaching the Colum-
bia, instead of at once and effectually damming up the stream,
in the struggle which ensued the glacier was held in check
and its foot dissolved by the impetuous river. Besides this
it had lateral means of discharge through Knapp’s and Na-
varre’s coulées;—hereafter to be more particularly described.
These lateral ice-streams also emerged upon the Columbia
river, but at a lower point, where the valley is wider; and to-
day great benches and banks of morainic and half-sorted ma-
terial may be found distributed for several miles on the Doug-
las county side of the river.

The Methow glacier reached the Columbia some time
later, encountering it at a point which may be called the little
bend. For here the river, after pursuing a general westerly
course for upwards of 80 miles, turns sharply within the space
of half a mile to begin its southern course. At this exact
point the Methow valley opens to the west. And here is pre-
served a most interesting record of the time when the ice
from the west began to encroach upon the river channel.
Upon becoming dammed the river rose to a hight sufficient
to enable it to cut across the corner, where it excavated a
deep transverse channel some 150 feet down into the granite,—
as shown by accompanying diagram (No. 1). The glacier,
being relieved laterally, left the river in undisturbed posses-
sion until the final damming of its waters by the Okanogan
glacier.

’ It is by this latter glacier that the hardest work was done.
Being produced by a drainage area 200 miles long and 6000
miles in extent, it was slow in coming, but when it did arrive
it was not to be stopped by the Columbia gorge. It occupied
this latter completely, dividing right and left, but even so it
could not find relief for its great bulk and enormous pressure.
According to Russell it rose and overtopped the plateau op-

208 The American Geologist. October, 1898

posite, although it is especially guarded at that point by a
mountain rampart 2500 feet above the river. Arrived upon
this great upland plain, the glacier deployed to the south and
east, reaching as far as Coulée City in Douglas county. The
evidence of this occupation is furnished by the bowlder-strewn
prairies, miles in extent. Great masses of basalt were wrenched
off from the edge of the plateau and deposited over the prairie
in blocks up to 60 feet in diameter. The underlying granite
as well is represented in the boulders.

The appearance of the Okanogan glacier was fraught with
the gravest consequences to the Columbia river. Its waters
were effectually dammed until they attained a hight sufficient
to begin their glacial drainage southward through what is
now called the Grand coulée. This valley, with a width of
from one to four miles, bounded by perpendicular walls of
basalt 400 feet high, though at present unoccupied except by
stagnant lakes, was originally a fracture line in the lava, which
subsequent preglacial streams drained to the north and south,
from near Coulée City. The waters of the Columbia deep-
ened this channel and planed down the divide. It had, how-
ever, to enter the southern portion by a waterfall approxi-
mately 400 feet high, in comparison with which Niagara is
a mere bagatelle.

This brief account of the Grand coulée makes a fitting in-
troduction to the subject of coulée formation. Recalling to
mind our first definition of coulées as valleys which are unoc-
cupied or at least not adequately occupied by running water,
and which have comparatively level floors, we may need to
add further that, in general, we shall expect to find these
coulée floors with a low divide, sending the superficial drain-
age waters toward either end. This is done that we may ex-
clude mere “draws” and dry creeks, and also valleys whose
streams have been depleted by the capture of their head-
waters. Thus limited, it will appear that the coulées of Okan-
ogan and adjacent counties are ice formed,—either directly
by ice action, or indirectly on account of the glacial occupa-
tion. With this in view, we may distinguish with reference
to their origin three forms of coulées: 1. Valleys occupied
temporarily by preglacial streams. 2. Preglacial valleys
whose waters were permanently diverted by the ice. 3. Val-

Glacial Phenomena in Washington.— Dawson. 209

leys actually excavated by the ice. Other varieties are pos-
sible and innumerable modifications may be found, but from
a somewhat careful study of the region I conclude these to be
the leading types. Let us consider these three forms, with
examples of each.

Of the first, Grand coulée must ever be the typical ex-
ample. Enough perhaps has already been said to indicate its
pertinent features. Moses’ coulée to the westward may prove
to be of this sort, but its phenomena have not been closely
studied. Regarding it on the map, I have even hazarded the
conjecture that it marks a stage of Columbia river drainage
previous to the Grand coulée occupation, but this is, I confess,
extremely improbable. The Little Bend coulée, already re-
ferred to, evidently belongs to this class. There was little
opportunity for the formation of coulées of this class in Okan-
ogan county proper because of the complete occupation of
ie Ice:

Of the second class, the most prominent example is the
one already figured by Bailey Willis, the old valley of the
Similkameen river. This stream used to run south parallel-
ing the Okanogan river for 30 or 40 miles, before joining it
lower down. During the decadence of the glacial period the
ice occupied this portion of its channel—being continually
fed from the west—while the waters of the Similkameen, par-
tially released, were accumulating on the north. Soon the
water of the lake thus formed began to cut across a low di-
vide to the east, and this action was continued until today the
Similkameen deserts its old valley by a sudden sharp turn to
the north-east, Miner’s bend, and passes through a narrow,
deep-cut canon to join the Okanogan at Oro. The glacier
left abundant evidence of its presence in the old valley. for it
heaped up morainic material in the central portions until a
tributary stream, the Similihekin, upon entering the valley,
turns and meanders slowly north over the drift, proceeding for
20 miles, or until it joins the Similkameen, in a direction con-
trary to the old stream ;—certainly a remarkable instance of
filial devotion in rivers. Of the southern extension of this
coulée, Bailey Willis says: “From the Three Pools southward
the drift surface is dotted with kettle holes: * *°* The
waters of Fish lake are held by a gravel dam, from beneath

210 The American Geologist. October, 1898

which a small stream escapes into the very narrow and
crooked upper channel of the southern portion. The descent
from Fish lake is very rapid, and is strewn with boulders of
large size. After passing a very deep and narrow pool three-
fourths of a mile long, into which the brook sinks, the valley
opens out between limestone bluffs and drift terraces, and ends
abruptly in a cul de sac at the head of Johnson creek, the fur-
ther continuation, whether southward or south-eastward, be-
ing now completely filled.” With regard to this alternative,
[ should unhesitatingly say that the preglacial drainage was
through Johnson creek. Any one approaching the middle
portion of the valley occupied by this little creek cannot but
be impressed by its depth and width, as compared with the
insignificant stream which drains it. It is, in fact, almost a
coulée. In spite of nature’s efforts to efface the record, this
explanation is confirmed by a study of the derivation of the
water which supplies Johnson’s creek. The drainage of Fish
lake is absorbed in the limestone belt, as indicated by the
quotation from Bailey Willis; but a small stream called Scotch
creek, which drains from the north-west, comes over the west-
ern terrace-wall of the Cul de sac through a slight notch, and
is absorbed by the gravel before reaching the floor. This
stream reappears a half mile or so east of the eastern ram-
part of the cul de sac, and is there called Johnson creek. The
lower part of this Johnson creek coulée is choked effectually
by the great terrace of the Okanogan, so that the mouth of
the old valley cannot be determined. Upon the retreat of the
glacier, the lower end of the old Similkameen valley terminat-
ing in the cul de sac, became filled with water. The lake
thus formed was drained, not by the clearing away of the ob-
structing drift, but by a narrow defile cut in the solid granite,
through which one may now pass horseback into Johnson
creek. (See diagram. No. 2.)

The drama thus enacted in the ease of the Similkameen
was reproduced on a smaller scale and in a simpler form a
few miles south at Spring coulée. This name is applied to the
lower end of the Salmon creek valley, below the point where
the stream turns sharply to quit the valley by a narrow gorge
running due east. So quickly and almost imperceptibly is
this movement accomplished that in coming down the valley

Glacial Phenomena in Washington —Dawson. 211

SHOWING
CUL-DE-SAG © Shp:
HEADWATERS OF JOHNSON CREEK

CONTOUR LINES DIAGRAMMATIC
ONLY (FROM MEMORY) ,

\ PORTION OF
\ SIMILIKAMEEN COULEE |

CODE: SAC

Diagram No. 2.

you are taken completely by surprise at finding yourself sud-
denly deserted by the stream. This is, of course, a simple re-
cessional phase, the lower valley having been occupied for a
long time by a persistent ice mass. (Diagram No. 3.)
Examples of the third class of coulées are the most numer-
ous. The fact has already been referred to that the Chelan
glacier found channels of discharge through a barrier range
to the southward by means of Knapp’s and Navarre’s coulées.
The latter of these is the larger and in some respects more
remarkable, but the former has been more carefully studied
and will be described briefly. An observer standing on the
north side of lake Chelan across from the north end of Knapp’s
coulée sees a low divide cutting deeply through an east and
west range of foothills, which rise from 1800 to 2500 feet
above the level of the lake; cutting deeply, I say, yet not
down to the lake level, for it ends, substantially, in a confu-
sion of irregular terraces some 200 feet above the lake. Pass-
ing through the four or five miles’ length of this coulée, we
find that the central portion is level for quite a distance, and
is bounded by abrupt mountain walls, while the slope in either
direction toward the ends of the valley is only four or five per
cent. It is an ice-hewn valley, a discharge pipe of the Chelan
glacier. Originally consisting of two opposite valleys heading
at near the same point on the divide, it was selected by the

212 The American Geologist. October, 1898
Woy g 2 ——
Bs <
—! os
=) eitges Nae 3
a6 pe q
Oye er cae :
os Z Jor & i
Zi) eee :
ng Ay ea g
Seebecep aes
Y) Ws

Diagram No. 3.

ice as presenting the easiest avenue of escape across the ram-
part; 1. e., the lowest point, and was subsequently deeply ex-
cavated by the long continued and gradually concentrated
ice-flow. Today its superficial features of kettle-holes and
morainic banks have not been obliterated nor even noticeably
modified by subsequent drainage.

(1). These recessional deposits are fairly characteristic of
coulées of the third class, as also of the second. Antwine’s
coulée, which connects the Methow river at a point four miles
above its mouth, with the Columbia river, over ten miles
away, is so obstructed by local and foreign boulders that its
passage is with difficulty effected on horse. Moreover, the
lower or southern extension of this coulée is bounded by
walls of terrace material, which were evidently accumulated
at a time when the occupation of the Columbia gorge by the
still moving Okanogan glacier prevented the free escape of
drainage waters.

(2). Below the end of Antwine’s coulée there exists an-
other extending in substantially the same direction as the
main Columbia valley. This latter is unique from the fact that
its general outlines were probably determined by a split in the
mountain, the portion toward the river falling away and re-
yealing a fissure a thousand feet in depth, and scarcely wider

Glacial Phenomena in Washington.—Dawson. 203

at the top. The bottom of this rent, which is a mile in length,
is occupied at present by glacial debris.

(3). To this third type also belong many small coulées
which parallel for short distances the main valleys of the
county. These are generally deep and narrow gorges which
the ice has hollowed out between some sturdy outlying spur
and its parent mountain. At least seven such well marked
miniature coulées are to be found within a radius of four miles
from Chelan.

Bearing no less emphatic testimony to the occupation by
the ice, the terraces of Okanogan county deserve particular no-
tice. I only regret that my observations with reference to these
were not more accurate, and especially that a table of levels
was not prepared. Mr. I. C. Russell has offered some com-
ments upon the appearance of the terraces about Chelan, but
I must confess that I cannot agree with some of his conclu-
sions, and especially those relative to a lake Lewis. It might
be that a careful re-examination of the facts would demon-
strate the grounds for his supposition, but inasmuch as his
pamphlet did not come into my hands until since my return,
I must beg leave to explain the facts in another way, and to
call attention in place to a few discrepancies in Mr. Russell’s
notes.

The subject may be divided into river terraces and lake
terraces. To the former we have already alluded in the topo-
graphical sketch. In speaking of these features, Mr. Russell
first describes a “great terrace” as noted in the Columbia
valley a little below the mouth of the Chelan river, “the sur-
face of which is 700 feet above the Columbia.”’ Afterward he
alludes to this “great terrace” repeatedly as appearing in his
progress up the stream. Now this great terrace can be none
other than the 300 foot terrace, which has notable expansions in
the Howard or “poverty” flat, above the mouth of the Chelan
river; in Paslay’s bench above the mouth of the Methow: and
in the Okanogan flats, with which also the great terrace of the
Okanogan river is substantially continuous. Either Mr. Rus-
sell is mistaken in his estimate of the hight of the true, great
terrace, or else at fault in trying to correlate his 700 foot ter-
race with the “great terrace.” This point is important, for
Mr. Russell on this mistaken supposition proceeds to correlate

214 The American Geologist. October, 1898

“a broad terrace 325 feet above the lake” in the Chelan valley
with the “great terrace” of the Columbia valley, and for this
purpose invokes the aid of a great post-glacial “lake Lewis,”
which should have formed the two terraces at the same time.
The Chelan terrace, by the way, is more nearly 225 feet above
the lake, and even so, some 250 feet above the top of the Co-
lumbia terrace.

We shall return in a moment to speak of the conditions at
the foot of lake Chelan, but first a word further as to the
Columbia terrace. That it is a river and not a lake forma-
tion would seem to be sufficiently evidenced by the fact that
the terrace maintains its relative hight above the rivers—Co-
lumbia and Okanogan—throughout a distance of at least forty
miles. Thus the absolute hight of the terrace increases as we
ascend the streams. Furthermore, the material of the terraces
shows nothing of the offshore gradation which we should ex-
pect in a still water deposit. This point cannot, of course, be.
urged if one insists with Russell that the whole channel was
filled by lake-formed terrace deposits; but this is manifestly
improbable.

The Chelan glacier, when it encountered the Columbia
river, began to deposit a moraine across the mouth of its val-
ley. This deposition was kept up at least until the Columbia
valley was occupied by the southward flowing, west fork of
the Okanogan glacier. As the ice began to retreat, it is pos-
sible to suppose that both the Chelan and Methow glaciers
began to withdraw at first, while the Okanogan glacier still
filled the Columbia gorge, and that the ice of the latter bulged
into and followed the path of the retiring glaciers. This ap-
parently out-of-the-way explanation is called for because of
the remarkable presence of certain boulders in the Chelan and
Methow valleys. Distributed all along the western bank of
the Columbia river, and at certain points in the lower Methow
and Chelan valleys, there occur large rounded masses of
basalt, boulders, brought by the ice. I saw two on the
Methow at least five miles from the mouth of the river.
Another near lake Chelan weighing hundreds of tons
lies half buried in the hillside about fifty feet above
water on the north shore of the lake, and also five miles
from the Columbia. The possible parent beds of these

Glacial Phenomena in Washington.—Dawson. 21

traveled blocks can be found only on the east bank of
the Columbia or in the region east of the Okanogan river,
that swept by the eastern flank of the Okanogan glacier.
A notable aggregation of these boulders is to be seen in the
Columbia valley a little below the entrance of the Methow.
The appearance of the great boulder-field there found is diffi-
cult to account for. Starting on the bottom land only a little
removed from the high water line of the Columbia river, large
blocks of rock as big as houses are scattered over forty acres.
As we ascend the gently sloping hillside going westward, we
have to pick our way through promiscuously heaped boulders
of gradually diminishing size. As we traverse the hill for a
half a mile, we shall find a tolerably constant gradation of
size until the upper limits of the field are obscured by terrace
material. Now, throughout this rock scale the proportion of
basalt to granitic boulders is about one in a hundred. They
mark, perhaps, a recessional phase, at a time when the Okan-
ogan glacier was held in check by the now released but swollen
waters of the Methow, which forced the glacier to drop its load
and was yet fierce enough to remove the finer material. Fur-
ther than that, their present sorted appearance is hard to ex-
plain.

But to return to the subject of terraces: we notice that in
the Chelan valley there must have been a time after the par-
tial recession of the ice, while yet the ice occupied the Co-
lumbia gorge, when the pent-up waters filled the lower end of
the valley. This feature is indicated at various levels, but espe-
cially at the 225 foot level, where the material of lateral mo-
raines was worked over and spread out in benches, which are
now capped by a fertile soil.

One of the late phases in the retreat of the lake waters is
to be read in the Wapato district. This is a comparatively
level section of land which occupies the angle of a bend in the
lake, where it emerges from the north and south Narrows to
open into the eastward-stretching terminal sheet. At the knee
of this bend a valley opens westward. Down this valley a
glacier flowed. Moreover, it did not tarry until its foot rested
against the angle of the Wapato section, thus forcing the lake
waters to cross between it and the highland opposite. The
broad and shallow channel thus formed is now completely

216 The American Geologist. October, 1898

evacuated by the lake waters, and is occupied through its five
or six miles extent only by occasional alkali sinks.

Lake Chelan is held in place by a dam of glacial debris.
The terminal moraine of the Chelan glacier chokes up the
lower valley and holds the lake back at a level 325 feet above
that of the Columbia river, which sweeps its base. Instead of

Ger - 20Fr.
DEEP

LAKE CHELAN

CHELAN MORAINE

REGION IN GENERAL IS OF GRANITE,
BUT LOCALLY COVERED BY ALLUVIUM
CONTOUR LINES DIAGRAMMATIC ONLY.

ROADS aoe: SCALE, 34"= I MILE.
<

Diagram No. 4.

excavating a channel through the heaped-up materials of the
moraine and so reducing the lake to its preglacial level, the
outlet of lake Chelan has found another route,—a precipitous
channel through the granite. This course is, perhaps, deter-
mined, as Mr. Russell suggests, by the fracture-line between
two immense fallen rock masses, which were at some time split
off from the north-east corner of Chelan butte. At the time of
the Kokshut mountain disaster water coming from some point
in the river burst forth from under the moraine, and has since
persisted as a series of springs,—making a veritable garden
spot at La Chapelle’s landing, where was only barren sand be-
fore. If it be true that the Chelan river, instead of cutting
through the granite, has merely followed a break in the rock,
then no reliable estimate of its age can be formed on this basis.
(See diagram No. 4.) Better results, however, may be ex-

Microscopical Light in Geological Darkness.—Claypole. 217

pected from work at the head of the lake, for the Stehekin
river, which occupies the continuation of the valley to the ~
west, has been filling in the head of the lake for a consider-
able time and has shortened its length by several miles.

No account of the ice work in Okanogan county would be
complete without some reference to its present glaciers,—the
residual members of the old ice system. Little has, however,
been done to explore the ice fields which occupy the rugged
region to the north and west of lake Chelan and the Methow
river. Prospectors report them as being numerous through-
out that country. From the summit of a high mountain west
of Chelan, Wright’s peak, itself bearing a small glacier, I have
looked off upon.a region where they might be counted by the
score. Some-of the central mountains seem to be completely
covered with ice and snow, except for the aiguilles which
pierce through. Although moist conditions still prevail, it is
probable that we are witnessing a period of slow retreat.

MICROSCOPICAL LIGHT IN GEOLOGICAL
DARKNESS.*
By E. W. CLAypoueg, Akron, O. 7

Gems and other crystals had long been known, especially
since the tine of Brewster, to contain minute cavities partly
or entirely filled with a liquid whose nature was unknown.
But by the study of a few specimens Sorby succeeded in de-
termining it in several cases. _Among these was one which
deserves to become classic on account of the peculiar advan-
tage which it gave to our pioneer in the investigation. This
was, indeed [ hope I may say it is, though I do not know its
present abode, a sapphire containing a cavity of a tubular
form. It was so regular in its bore that it served the pur-
pose of a natural thermometer, and by its use Mr. Sorby
reached a conclusion at once surprising and important. I
should mention that this little thermometer was one-fourth
of an inch long by about one-eightieth of an inch in diameter,
a truly microscopical instrument. On experimenting with

_ *Extract fromthe president’s address before the American Microscop-
ical Society, 1897.

218 The American Geologist. October, 1898

this little instrument Mr. Sorby found that the liquid, which,
as shown, filled one-half of the cavity at ordinary temperatures
such as 50° F., expanded so rapidly that its volume was
doubled and the cavity was full at 89° F. This increase of
bulk within so narrow limits of temperature at once excluded
all ordinary liquids, and by further investigation and com-
parison Mr. Sorby was able to decide that the substance was
nothing less than liquid carbonic acid, the only known liquid
whose rate of expansion was equally great. Here was a solid
fact contributed by the microscope toward the solution of
some of the difficult and complicated problems presented by
the physics of the earth’s crust, and, again, we shall find from
this study of a drop of liquid almost infinitely little, contained
in an instrument equally minute, may flow results of great
moment and far-reaching consequence. It is not the size but
the solidity of the premises that authorizes the conclusions.
Granting, as we must, that the little drop is carbon-dioxide
in the liquid form, we can safely advance by reasoning on the
known properties of this substance somewhat as follows:
The critical temperature of carbon-dioxide is about 88° F.
(87.6°), that is to say, above this it exists only as a gas, and can
by no pressure be liquified. Now it is in the highest degree
improbable that at the time and in the conditions when the
crystalline rocks were formed the surface of the earth was
below this point. On the other hand, we may confidently rely
on its having been far above this critical temperature. Obvi-
ously then the carbon-dioxide must have been sealed up in the
crystals in a gaseous state—a bubble of carbonic anhydride.
Here the problem becomes indeterminate. Both the original
temperature and pressure are unknown. But arguing from
what we know of the physics of this substance we may deduce
the following conclusion: At present ordinary temperature,
50° F., the pressure in the microscopical registering ther-
mometer of Mr. Sorby, must amount to about forty-eight at-
mospheres or 720 pounds on the square inch. This little in-
strument was exactly filled at 89° F., very near the critical
temperature. At this point the minimum pressure which will
enable the carbonic anhydride to retain the liquid state is
seventy-three atmospheres or 1,100 pounds on the square inch.
Consequently, if as inevitable, we assume a higher tempera-

Microscopical Light in Geological Darkness.—Claypole. 219

ture than 88° F. for the globe at the time of the crystallization
of the minerals, we must also assume a higher pressure than.
seventy-three atmospheres as one of the conditions prevailing
during crystallization.

This, however, is doubtless far too low for both. Instead
of 88° Mr. Sorby and others consider the temperature of con-
solidation to have been nearer 700° F. Mr. J. C. Ward, a few
years ago, following in the footprints of Mr. Sorby, carried his
work a little farther. Assuming his datum of 680° F. as the —
temperature of crystallization of the minerals, he shows that the
corresponding pressure was not less than twenty-six tons, or
3,500 atmospheres on the square inch, and that these micro-
scopic flasks must have been charged with their effervescing
contents under that enormous compression.

This is equal to the weight of a mass of overlying strata
52,000 feet thick. It is not right, however, to attribute the
whole of this to the weight of overlying strata. There is no
doubt that it is the resultant of this and the violent lateral com-
pression to which the contortion and folding of the gneiss is
due. The latter is probably the larger of the two components.
Mr. Ward’s conclusion is that the granite of Skiddaw, in Eng-
land, was formed at least six miles below the surface, a depth
at which the temperature is normally very near Mr. Sorby’s
datum of 680° F.

This is surely a vast deduction from data, microscopically
minute, and seemingly insignificant. But insignificant as one
of these “crystal flasks,” as they have been aptly called, may
be, we are not dealing with one alone but with vast numbers,
for investigation has revealed them by myriads and by mil-
lions, and not in gems only, but in other crystalline minerals.
In size they range between the one-thousandth and the fifty-
thousandth of an inch, but they are so multitudinous as often
to impart a white tint to the crystal, and many specimens of
milky quartz owe their whiteness solely to the presence of
these innumerable bubbles. In some of the Cornish granites
the cavities make five per cent of the volume, and yield four
pounds of the liquid to every ton of the rock.

Mr. Ward says: “Such is the minuteness of these cavities
and their number in many cases, that more than a thousand
millions might be contained easily within a cubic inch of

220 The American Geologist. October, 1898

quartz.” We shall presently quote another writer giving the
same testimony.

I must here digress for a short time from the main line to
trace a tributary that meets it at this point and whose course
it is necessary to have in mind in order to develop the argu-
ment. The geologist, regarding the past history of the globe
with a critical eve, has long been amazed at the vast masses
of mineral fuel—coal, petroleum and gas—which he finds ac-
cumulated in the crust and especially on one horizon. The
carboniferous system, with its huge stores of free carbon, the
chief and almost the only resource of the world at present
for heat and power, and its hope for the future are to him, a
standing enigma. The botanist assures him that all has been
extracted from the atmosphere by the agency of green plants,
under the stimulus of sunshine. No other process is known
whereby this precious element can be severed from its com-
pounds and isolated in free form in any appreciable quantity.
Indeed its separation in the laboratory is a somewhat difficult
and refined experiment. But this assurance of the botanist
darkens rather than clears the enigma of the geologist. Re-
lying with confidence on the botanical principles of his broth-
er-student, which are confirmed by so many concomitant
proofs as to be quite unassailable, such as the vegetable struc-
tures, leaves, stems and fruits found in the coal, he is yet un-
able to see where these plants obtained so vast a supply of
carbon. From a careful quantitative study of the atmosphere
he learns that the sum total of this element therein contained
is vastly less than that which now lies buried in the earth, so
that to accumulate another stock of mineral fuel equal to that
which we are now using so freely and squandering so reck-
lessly, would be an impossibility. The material is not pres-
ent in the atmosphere, and what is not there can not be taken
away. Without troubling you here and now with the calcu-
lations, I will merely give sufficient results to establish my
statement and to enable you to follow me with confidence.
The whole amount of carbon in the air to-day, in the form of
carbon-dioxide, does not exceed 150 to 200 cubic miles—a
sufficiently large amount, you are ready to say when you try
to realize what it expresses. A single cubic mile of coal al-
most passes comprehension. The world’s entire annual con-

Microscopical Light in Geological Darkness.—Claypole. 221

sumption does not exceed 350,000,000 tons, so that one single
cubic mile, 7,000,000,000 tons, would suffice to supply us all
for twenty years. But the stock of coal and the like, actually
in the ground, far exceeds, as I have said, even this enormous
figure. To attain anything like exactness in such data is
manifestly impossible, but we cannot assign to the world’s
store of mineral fuel, or the coal contents of our coal fields,
. oil fields and the like, a less amount than 2,000 cubic miles at
the least, or about ten times what could be obtained from the
air. Here lies the enigma, and, as you see, the botanist has
not furnished any interpretation of it.

It is easy to say, as many have said, that there was a larger
supply of carbonic acid in the atmosphere then, than there
isnow. This is cutting rather than untying the Gordian knot.
Perhaps it was so. The explanation is plausible. But the
plausible in nature is not always or usually the true.

Time will not allow a full discussion of this topic this even-
ing. It must suffice to indicate, in a general way, the reasons
which preclude us from accepting the reply as good and suffi-
cient.

In the first place, let us consider the demand of the geolo-
gist. We have mentioned the coal beds, the oil and the gas,
but these are far from being all that he requires. There are
in the earth huge beds of black shale, holding often from 5
to 15 per cent. of carbonaceous matter. This far exceeds
the mass of the coal and we may safely put the figure up
from 2,000 to 20,000 cubic miles. Alexander Winchell’s
total is nearer 30,000. Then the vast stores of peat and the
whole animal and vegetable creation, or at least the carbon
which they contain, must be included, and this defies exact
calculation. Lastly, the mass of coal that has been destroyed
by erosion must be added—small though it be beside the vast
total. Considering all these it seems perfectly safe to set down
the mass of unoxydised carbon in the earth’s crust at 50,000
cubic miles, or 250 times as much as that now existing in the
air—a proportion of 10 per cent.

Facing this fact the botanist is scarcely willing to admit
that plants could flourish in such a medium. Ferns and their
allies have been grown in cases charged with an atmosphere
containing 10 per cent. of carbonic anhydride, and possibly

222 The American Geologist. October, 1898

so large a proportion may have been consistent with the
existence of the cryptogams of the early eras. Botany cannot
give an absolute denial. Experiments on this point are few
and not very definite. Prof. Daubeny, of Oxford, stated
nearly fifty years ago, in a paper read before the British
Association in 1849, that ferns and their allies cannot bear
more than Io per cent., but could exist in an atmosphere
containing 5 per cent. of carbon-dioxide. Prof. Boussin-.
gault reported, in 1864, that different plants flourish best in
atmospheres ranging from 8 per cent. downward. We may
therefor infer that the above requirement of the geologist is
close to, if not above, the limit of tolerance of plants allied
to those by which the mass of our coal was made, and that
on this ground it is scarcely tenable. _

On the zoological side the evidence is also uncertain.
Some of the lower animals, such as fishes and amphibians,
are tolerant of a far larger amount of carbon-dioxide than
can be endured by the higher groups. But it can scarcely
be probable that even they could live in an atmosphere con-
taining as much as 10 per cent.

However, setting aside both these as inconclusive, a physi-
cal objection remains to be considered of more serious im-
port. By calculation we find that the conversion of this mass
of carbon into carbon-dioxide would absorb all or nearly all
the oxygen in the air and leave it devoid of that essential ele-
ment. We may, therefore, safely assert that whatever the
earth’s atmosphere may have been in the very early times, the
carbon now in the crust cannot have existed as carbonic acid
in the atmosphere at any one time since animal life began.

Returning, then, to our former ground we see that, with-
out dogmatizing on the primitive atmosphere, we are unable
to accept this plausible explanation as a good and sufficient
solution. We cannot hypothecate a sufficient capital stock
of carbon to meet the immense and continuous drafts that
have been made upon it.

So strongly did one of our most able chemical geologists,
the late Dr. Sterry Hunt, feel this difficulty, that he was
driven to make the suggestion that the earth had picked up the
needed material from the space-realms during her annual and
secular journeys—a remark which Alexander Winchell says

Microscopical Light in Geological Darkness.—Claypole. 223

is “highly suggestive.” But if we can realize the figures of
some modern molecular physicists regarding space we can
hardly entertain the suggestion, for they tell us that in the
interplanetary regions there is only one molecule of any kind
in 10°** cubic miles of space. In such an absolute, awful
solitude, the earth can surely not have been able to gather up
the needed carbon-dioxide, though she had sought it from
pre-Cambrian times down to the present day.

But here the microscopist comes upon the field and offers
his services in the cause of peace. In diplomatic language,
he proposes to act as mediator. He points out, as I have
already said, the minute cavities existing in the crystalline
rocks and shows that in them is hidden a store of carbonic
acid, hoarded, as it were, in the pockets of mother earth, in-
finitesimally small but infinitely numerous, and he suggests
that possibly here a source may be found from which the
geologist may get his coal and the botanist his carbonic acid,
without alarming the zoologist for the safety of his animals.
He shows that on this view it is no longer necessary to as-
sume its presence in the atmosphere all at the same time. In-
stead of this he suggests that it may have been, and prob-
ably was, set free almost atom by atom as the crystalline rocks
yielded to erosion and these “sealed flasks’? were, one after
another, burst open by the pressure within.

At first blush we may be disposed to laugh at the sugges-
tion and to deem such microscopical contributions of small
comparative value when so vast a demand is made. But it
is well to recollect that “many a little makes a mickle.” Let
us look at the matter quantitatively for a moment, for here
must lie the crucial test. If our theory fails here it fails al-
together, though if it pass this test its ultimate success is not
hereby assured.

Since the investigation by Mr. Sorby, to which I referred
at the outset, little advance has been made until quite recently,
when a stimulus was given to new experiments by the mar-
velous discovery of argon in the atmosphere. ~.we distin-
guished chemists who were engaged in that most remarkable
investigation turned their attention to the gases contained in
various minerals, among which were those of the crystalline
rocks: And ina paper recently read before the Royal Society

224 The American Geologist. October, 1898

(March, 1897), Prof. W. A. Tilden stated, as the outcome of
some work on quartz, feldspar, and the other constituents of
granite, gneiss, gabbro, schist, basalt and other minerals, twen-
ty altogether, from different horizons and widely distant lo-
calities, that they all yielded gas in which hydrogen is the pre-
ponderating element. Next to hydrogen the most abundant
is carbonic acid. And he further makes the important state-
ment that the volume of gas given off by these rocks, and
which comes entirely from the minute cavities within them,*
ranges from 1.3 to 17.8 times the bulk of the rock; that is to
say, that a cubic mile of stone would give out from one to
seventeen cubic miles of gas. Considering these figures the
problem begins to assume a new aspect and our next ques-
tion is, How many of these cubic miles of rock have we at
command? Because it is evident that if we only have miles
enough we can get enough carbon-dioxide.

At this point in the enquiry I was stopped for a while.
How is it possible to ascertain the amount that has been worn
off the surface of the crystalline rocks since geologic time
began? I laid the subject aside for a time. But soon the
thought occurred that the mass of the sedimentary rocks, with
a few corrections, must equal the amount worn off the crys-
tallines since the days when these latter composed the whole
surface. But it is not easy to obtain even this datum and any
result must be merely approximate.

I may here be allowed to digress for a moment to explain.
All geologists who accept the principle of cosmic evolution
(and in the present day few can be found who reject it) are
agreed that the earth has cooled and consolidated from an
early liquid mass, consisting of slaggy, glassy and stony
material resembling modern lavas. From this hard and
intractable rock-mass all our sandstones, shales, clays and
limestones have been slowly separated by the disintegrating

*As a proof of this fact Prof. Tilden incidentally remarks: ‘The gas
is apparently wholly enclosed in cavities which are visible in thin sec-
tions of the rock when viewed under the microscope, but as they are ex-
tremely minute, very little gas is lost when the rock is reduced to a
coarse powder, anda result of experiment in one or two cases | find that
practically the same amount of gas is evolved on heating the rock,
whether it is used in small lumps or in powder.”

Microscopical Light in Geological Darkness.—Claypole. 225

and dissolving action of water. Over and over again have
these strata been broken up and swept away by rains and
rivers, until the ancient crystallines have gradually been
buried under their own ruins and now occupy comparatively
a small part of the surface. None the less has every particle
of the sedimentary strata,-except carbon and carbon-dioxide,
been derived from their steady destruction, the amount of
which must, of course, be approximately equal to the mass
built up from their ruins.

Had the geologist senses sufficiently exalted he might hear
the miniature explosions, as one after another, or, many at
the same instant , these little “‘sealed flasks’ burst and dis-
charge their highly compressed contents. In grinding down
a thin slice, myriads of them are opened and their gases lost.
So in nature, as erosion thins down their crystal walls, these
ultimately become so weak that they can no longer with-
stand the bursting pressure within and a microscopical ex-
plosion ensues.

The area of the dry land of the globe equals about 60,000,-
ooo square miles, and by far the greater part of it is covered
with thick sheets of sediment. Deduction must be made for
the areas where these are absent and the old crystalline rocks
still form the surface. But, on the other hand, a large addi-
tion is due on account of the sea-margins which for 200 or
300 miles from shore are covered with the wash from the land.
With the deep sea I will not here deal.

I assume, then, that one of these corrections will counter-
vail the other and that the area of the sedimentary strata is
equal to that of the present dry land or 60,000,000 square
miles. Now the thickness of these rocks is very various,
ranging from ten miles down to nothing. The former figure
is seldom found, but it appears to me that to assume an aver-
age depth of one mile is not unreasonable. This will give us
for the whole mass eroded from the ancient crystalline rocks
the sum of 60,000,000 of cubic miles.

Regarding the quantity of carbon-dioxide contained by the
rocks on which Prof. Tilden experimented, the following
figures are taken from the report of his paper given in the
Chemical News for April 9, 1897:

226 The American Geologist. October, 189%
In 100 vols.

Vols. Cope

Granite, near Dublin, acid; Plutonic . 3. = 5.0 9-4 90.6
Granite, Ardshiel, acid, Plutonic . . : 6.9 79.5 20.5

| Greisen, Altenburg, Sax, altered, Plutonic. : 1.8 13.6 86.4
Granulite, India, altered, Plutonic... . 2.0 A877 5728
Quartz-Schist, Co. Down, Metomorphic . . 2.8 23°00 7760.

g | Fuchsite Schist, Barodo, Inn., Metamorphic . 4.2 20:9) 170.2

=} Corundum rock, Rewah, Ind., Ind., Metamor-

H | Dic ar 3.5 26.0 74.0
Pyroxene Gneiss, Ceylon, Metamorphic. 73 84.4 15.6
Gneiss with Corunbum, Seringapatan, Metamor-

| phics : 17.8 18.0 82.0

_; | Gneiss with Garne and Graphite, ( Ceylon j 4.5 11.0 89.0

= (Gneiss, Himalayas ; Fe. Its teha)ys'=

Bf Gneiss : 5-3 82:36

< ‘ Felspar Ie3 0407. S22

2 13—79-2 13-522

: Beier.

a 5.4 4 a

These results give us an average of five and a half volumes
of gas for every volume of rock, and of this quantity 40 per
cent. was carbon-dioxide. Combining the averages we find
that these Archean minerals yielded between two and three
times their volume of carbon-dioxide. Combining again with
the previous result—60,000,000 cubic miles of eroded crys-
talline rock—we obtain about 150,000,000 cubic miles of gas.
Of this the three-thousandth part will be carbon in the solid
form.

In this way the final result is reached; that by these
minute contributions we get about 50,000 cubic miles of car-
bon, equal to at least 60,000 cubic mules of coal. As the
total stock of existing coal amounts to only about 2,000 cubic
miles, or with all the other forms of unoxydised carbon, to
not more than 50,000 cubic miles, we have a supply ample and
more than ample for the demand.

In such an investigation I need not caution anyone against
laying much stress on the exact figures here given. A calcu-
lation when the data are so indefinite can but be approximate.
Yet I hope I have shown that allowing for all inaccuracy we
have here a supply of the precious element, carbon, from
which the geologist can obtain his coal without offending his
brethren, the botanist and the geologist, by insisting upon a
greater amount at any time in the atmosphere than they are

Microscopical Light in Geological Darkness.—Claypole. 227

willing to allow. Here we have a supply from which it can
be drawn as wanted without disturbing the existing balance
of atmospheric composition, or compelling us to assume that
in the early days of life the air was materially different from
what it is at the present time.

I am sure it must be interesting to the working members
of the American Microscopical Society to see how the inves-
tigation of these minute bubbles in the crystalline rocks leads
on to the discovery of a possible origin of the carbon in our
coal. To any geologists present I must excuse myself for
considering only part of the problem and saying nothing
of the other stores of this carbonic acid in the rocks of the
earth compared with which the coal and other free carbon in
the earth is a mere vanishing quantity. But the conditions
differ and the solution of that problem must differ also.

The unconsidered elements would, if introduced, vastly
and unduly extend this discussion, while they would not in
any way conflict with what I have said. They would com-
plicate, but not invalidate the argument. I have merely
endeavored to put forward and maintain a mechanism where-
by carbon-dioxide could be obtained as wanted by the plant-
world without charging the atmosphere with the whole
amount at once.* I have shown how the deposit in the at-
mospheric bank can be obtained through the receiving teller
while the paying teller is constantly releasing it in response
to checks on demand. .

Meanwhile I have given you a glimpse down some of the
long vistas of geologic time. I have brought before you
some of the processes of world making—some actual records
of zons long gone by—some relics of remote conditions en-
tombed when time was young. You have in imagination,
seen the glowing lithosphere slowly cooling and crystallizing
and as the solid earth was built there were stored in its founda-
tion stones these samples of its primeval atmosphere, sealed

*An interesting possibility—I may say, from some points of view, a
probability—-would lead us too far here, if we were to attempt its discus-
sion. But there is nothing unlikely in the supposition that the whole
oxygen of the atmosphere has been set free from its combination in the
form of carbon-oxide by the action of plant-life. Such a supposition is
beset with some difficulties, not, perhaps, insuperable, but it has many
strong reasons in its favor. }

228 The American Geologist. October, 1898

in their crystal flasklets. The building advances, the cooling
nucleus contracts, the cold and solid crust outside, being un-
supported, sinks and is crushed. You hear, as it were, the
creaking of the massive globe as its crystalline particles yield
before the inconceivable earth-force. Then—in that time,
not of disaster and catastrophe, but of slow, imperceptible
evolution—were graven on stone those mystic characters
which the microscope has interpreted to you this evening.

(Contributions to the Mineralogy of Minnesota. I.]

NOTE ON THE CHARACTERS OF MESOLITE
FROM MINNESOTA.*

By N. H. WincHELL, Minneapolis, Minn.

Mesolite. The most conspicuous, and the most collected
of all the Minnesota zeolites is mesolite. It has been wide-
ly distributed from Grand Marais and from other points
west from Grand Marais, under the name _ thomsonite.
Some of the specimens collected by the State Geological
Survey in 1877 and 1878 were examined by Peckham and
Hall (Am. Jour. Sci. XIX, 122, 1880), and from chemical
characters were considered thomsonite and that designa-
tion has been followed by the: survey in all later reports.
This mineral is usually white, but varies from white to pink
and to green, these colors alternating in superficial bands
forming colored circlets or rosettes which with its hardness
have rendered this mineral a gem of considerable beauty
and value.

It is strongly radiated in fine fibres, which are long and
rigid, in this respect differing from thomsonite, whose fibres
are coarser and somewhat irregular in direction and shape.
Specific gravity is 2.26.

Optic Characters. Sections cut perpendicular to the fibres
give the greatest light. Those parallel to the fibres are
sometimes almost invisible in certain positions, especially
in sections rather thin, owing to the very low power of

*This and other examinations of the rocks and minerals of Minneso-
ta were done primarily in the laboratory of Prof. A. Lacroix, Museum
d’Histoire Naturelle, Paris, and with his assistance, for which the writer
wishes to testify his gratitude.

Mesohte from Minnesota.— Winchell. 229

double refraction. These contrasts are sometimes strongly
brought out. For instance: in a section cut about parallel
with a lot of fibres the general obscurity of the field may be
relieved by scattered rhombs of very light and bright aspect,
whose perfect forms are bounded by right lines and which
occur sometimes in regular succession across the field of the
microscope. Suchrhombs ate sometimes nearly square, but
may also become much elongated in the direction of their
greater axes. As they become longer they also become
darker, and finally by continuing their elongation they blend
into the general structure and disappear in the fibrous mass
in which they lie. In other words, the fibres that happen to
be cut obliquely, or perpendicularly, give more light than
those that are cut parallel. This only shows that the plane
of the optic axes is perpedicular to the elongation of the
fibres. The same fact can be shown by the use of a section
cut parallel to the fibres, by the application of the quartz of
sensitive tint, when it will be seen that some are red and
some are blue, although lying adjacent, 1. e. some have xg
perpendicular and a negative elongation, and others have x,
perpendicular with a positive elongation.

Chemically, mesolite is quite similar to thomsonite, being
a silicate of alumina, lime and soda, with about 12 per cent.
of water. If the specimen be somewhat altered by weather-
ing, andif at the same time thomsonite and mesolite be in-
timately ingrown, as sometimes happens, it is evident that
the result of a chemical analysis would be a poor basis on
which to name the specimen.

The optic angle in mesolite is large, and in thomsonite it
issmall. This difference introduces another evident optical
character by which the two minerals can be distinguished:
viz. sections of mesolite cut parallel to the fibres are almost
uniformly illuminated whether they present ”, or 7g perpen-
dicularly, the amount of light along those axes being about
the same; but a section or thomsonite cut in the same way
will exhibit certain fibres that are much lighter than the
others. Thus quite light and quite dark fibres may alternate,
or they may occur in bundles. The light fibres are cut per-
pendicular to ~) in the greater optic angle and have positive
elongation, while the dark fibres are cut perpendicular to x,
in the optic angle and have negative elongation.

230 The American Geologist. October, 1898

Still, the chief and most marked optic character distin-
guishing this mineral from thomsonite is its much lower
double refraction. This mineral never shows colors, between
crossed nicols, in a section of ordinary thinness for micro-
scopical purposes, even when cut parallel to the optic plane,
while thomsonite uniformly rises into red, and to blue of the
second order, in sections of .03 mm thickness.

Localities. The most celebrated localities are at Terrace
Point, which encloses Good Harbor bay, a few miles west of
Grand Marais, and thence westward to Poplar river. It is
frequently seen as waterworn pebbles in the gravel of the
beach. It occurs at Lover’s bay, at Gooseberry River falls,
at Pork bay, Beaver bay and Agate bay. It is evidently a
product of alteration of labradorite in the coarse diabases
and gabbros. As such it occurs plainly at the east point of
Sucker bay (90B) where it results from a change in labra-
dorite. The most remarkable instances of such alteration
occur at Carlton’s peak, as discovered by Mr. A. H. Elftman.
Here the anorthosyvte holds nests of radiated fibres of meso-
lite as large as two or three inches in diameter.

{European and American Glacial Geology Compared, IX.]

GLACIAL RIVERS AND LAKES IN SWEDEN.

By WARREN UPHAM, St. Paul, Minn.

Among the several European countries through which our
travel last year extended, none was geologically more interest-
ing to me than Sweden, because it affords very instructive
comparisons with my earliest and latest geologic studies in
America, first, on the origin of kames and eskers in New
Hampshire,* and, last, on the glacial lake Agassiz,t in the
basin of the present lake Winnipeg. In the same year (1876)

*Proc. A. A. A. S., XXV, for 1876, pp. 216-225. Geology of N. H.
vol. III, 1878.

+Geol. and Nat. Hist. Survey of Minnesota, Eighth Annual Report,
for 1879, pp. 84-90; Eleventh Rep., for 1882, pp. 137-153, with map;
Final Report, vols. I (1884) and II (1888). Geol. Survey of Canada.
Annual Report, new series, vol. IV, for 1888-89, Part E, 156 pp. with
maps and sections. U. S. Geol. Survey, Monograph XXV, 1806, 658
pp., with 38 plates and 35 figures in the text.

Glacial Lakes and Rivers in Sweden.—Upham. 231

when my earliest geological paper was published, Dr. N. O.
Holst, of the Geological Surveyof Sweden, presented a closely
similar theory to explain the formation of the eskers (dsar)
of that country.* We then were wholly unacquainted with
each other, our conclusions, and the nearly similar earlier
suggestion of Prof. N. H. Winchell on the same subject, t
having been in each case reached quite independently. After-
ward, in the recognition and mapping of glacial lakes, held
by the barrier of waning ice-sheets, the first example in Amer-
ica somewhat completely traced and defined was the small
lake Contoocook in the valley of the Contoocook river in
New Hampshire, which I discovered while working under the
direction of Prof. C. H. Hitchcock in the survey of that state.
Within the subsequent twenty years the very large glacial
lakes of the St. Lawrence basin, which before were partially
defined by Newberry, N. H. Winchell, and others, have be-
come more fully known by the explorations of Gilbert, Spen-
cer, Taylor, Lawson, Leverett, and others, including the pres-
ent writer; and the largest lake of this class, first recognized
in 1872 as a glacial lake by Winchell, and named by me in
1879 in honor of Louis Agassiz, I have specially mapped
and described under the auspices of the geological surveys of
Minnesota, the United States, and Canada. It was therefore
a chief purpose in my travel through Sweden to observe and
learn as much as possible concerning its hundreds of eskers,
the ice-walled deposits of glacial rivers, and its scores of iden-
tified glacial lakes that were pent up in the valleys between the
western side of the departing European ice-sheet and the
mountainous Scandinavian watershed.

In its maximum extension, this ice-sheet, reaching out-
ward from Scandinavia to London, Brussels, Dresden,
Cracow, Kief, and Nijni Novgorod, covered an area of about
2,000,000 square miles, including the basins of the Irish,
North, Baltic, and White seas. Later its diminished extent,
when it had considerably retreated, is marked by the morainic
Mecklenburg or Baltic ridge, its continuation in Denmark to
Frederikshavn and the northwest coast, and, as I think, its far-

*““Om de Glaciala Rullstensasarne,”’ Geologiska F6reningens i
Stockholm Foérhandlingar, No. 31 (vol. III, pp. 97-112).

{tGeol. and Nat. Hist. Survey of Minn., First Annual Report, for
1872, p. 62.

232 The American Geologist. October, 189%

ther course to the shoals of the Dogger bank in the North
sea and to the Flamborough moraine on the northeast coast
of England.* Still later, this vast ice-sheet gradually de-
creased, forming marginal moraines at various stages of its
recession, until it was finally melted from the greater part of
Norway and from southern Sweden but remained on a large
central part of Sweden, where it had been accumulated thick-
est. The ice surface there, during the culmination of the
Glacial period, had doubtless surpassed in altitude the highest
mountains of this peninsula, and its westward outflow from
that area of ice-shed had carried many Swedish boulders over
the mountain passes into Norway. It is very probable, too,
that during the departure of this latest remnant of the Euro-
pean ice-sheet its axial tract of greatest though diminishing
thickness moved somewhat farther eastward, on account of the
generally eastward course of storms of rain and snow, as was
apparently true of the Minnesota lobe of the North American
ice-sheet and of its more eastern part which was the barrier
of the Laurentian glacial lakes. The Swedish eskers
and shorelines and deltas of glacial lakes preserve for us very
abundant records of the glacial recession in this part of Eur-
ope, enabling the explorer to follow the waning ice borders
to the latest tract upon which they opposed the drainage of
the present river valleys.

Within the cities of Stockholm and Upsala, and in their
near environs, I saw admirable new sections of the eskers
which are named from these cities, prolonged and massive
ridges of gravel and sand, much exceeding, in magnitude of
development, the eskers of Ireland and Great Britain, but
equalled or surpassed by the eskers of Maine, described by
Prof. George H. Stone, and by those surveyed and mapped
by me in New Hampshire. On large areas of southern
Sweden these very remarkable ridges of the coarsest modified
drift run in many nearly parallel southerly courses and on
either side receive tributaries from the north, so that as to par-
allelism in their mapping they resemble the abundant river
courses of Virginia and the Carolinas, of eastern Iowa, or of
Nebraska, Kansas, the Indian Territory, and Texas. A sec-

*See the sixth paper of this series. Am. Geologist, XXII, 43-49,
July, 1808.

Glacial Lakes and Rivers in Sweden.—Upham. 233

tion of the Upsala esker, reproduced from a photograph, is
published by Sir Henry H. Howorth in one of his most recent
papers,* with denial of the agency of an ice-sheet for its
origin; but if his opinions in this matter receive any cred-
ence among European geologists, they are less agreed than in
the United States, where, as Fairchild well said in his recent
American Association address, the glacial origin of the drift
has passed beyond the condition of a theory to that of a fully
demonstrated and generally accepted fact. The work of Stone
on the eskers and other associated modified drift of Maine,
partly published in his earlier papers and more elaborately
written for publication as a monograph of the United States
Geological Survey, should be well studied by geologists in
Europe, when such theories as the debacle explanation of the
origin of eskers and other drift formations are still acceptable
in their technical journals of our science.

Eskers are rare in Norway. One of their few notable lo-
calities in that country, and the only one that I observed, is at
Roros, 247 miles north of Christiania on the railway to
Trondhjem, and 2,060 feet above the sea. There an excellent
example of an esker series, in part compound, has an extent of
two miles, or more, from northwest to southeast, and rises
75 to 125 feet above the adjoining land, being on the east side
of the Glommen valley near its head. The gravel includes
cobbles up to one or rarely two feet in diameter. From the
courses of glacial striation in the region, it is known that the
recession of the ice there was toward the southeast, the drain-
age from Roros having passed northward to the Gula valley,
over a col crossed by the railway several miles farther north,
at 2,200 feet above the sea.

After the waning ice-sheet had relinquished nearly all of
Norway, remaining only on a narrow central tract in the wide
southern part of that country, and thence extending with in-
creasing breadth to northern Sweden, its obstruction across
the heads of valleys that sloped down toward the northwest
side of the receding ice caused them to contain glacially
dammed lakes. Some of these lakes have been partly explored
and mapped, so far as the mostly wooded and only sparsely

*Geol. Magazine, Decade IV, vol. V, pp. 195-206 and 257-266, May
and June, 1808.

234 The American Geologist. October, 1898

inhabited condition of the country permits, by Andrew M.
Hansen in the part of Norway southeast of the main water-
shed of the peninsula, and by Gunnar Andersson upon an area
of a hundred miles extent from south to north in Jemtland,
Sweden.

Hansen notes the altitude of the Norwegian glacial lakes
as ranging from 2,150 to 3,575 feet above the sea level, these
hights being known by the cols of the mountain belt through
which they outflowed; and their lengths, extending as the ice
retreated, became for the larger lakes, according to Hansen,
almost a hundred miles, with depths of about 1,000 feet.* ©

The region of the old glacial lakes described by Andersson?
is traversed by the railway leading from Trondhjem east and
south to Stockholm upon a distance of a hundred miles, from
Annsjon (Ann lake) past the Storsjon (Great lake), to Oster-
sund and Pilgrimstad. The Annissj6n (Ann glacial or “ice”
lake) and the Kallissjon of Andersson, outflowing through
passes of the western watershed, are marked over large tracts
of mountain-inclosed valleys by shore erosion and beach de-
posits and by delta terraces, at the hights, respectively, of
about 1,830 and 1,500 feet; and the later and considerably
larger Naldissjon, which extended over the present area of
the Storsjon, attained the size of about 1,700 square miles, its
altitude, determined by a lower outlet, being about 1,350 feet
above the sea.. The shorelines and deltas of these glacial lakes
appear to be as well developed in many places as the parallel
roads of Glen Roy or the beaches of lake Agassiz. The
general prevalence of forests, however, forbids tracing the
shores for long distances. When this shall be done at any
future time, it seems probable that the planes of the old lakes
will be found to have undergone differential changes of level
in the Postglacial uplift which is known to have affected the
whole country, although little indication of this is given by
Andersson’s maps. It is further to be remarked, also, that
the recession of the ice border could hardly have been so
uniform on this large district as these maps would denote; but

*Nature, vol. XX XIII, 18&6, pp. 268, 365.
+Geol. Survey of Sweden, Series C, No. 166, “Den Centraljamtska
Issj6n,” 38 pages, with 8 figures in the text and 3 maps, 1897.

Glacial Lakes and Rivers in Sweden.—Upham. 235

they are a good incentive for more detailed explorations, with
sufficient determinations of altitudes by levelling.

It would be highly interesting if the rate of final recession
of the ice-sheets of North America and Europe upon any parts
of their areas can be ascertained. The most definite testimony
given on this question by drift deposits in any locality known
to me was pointed out by Baron Gerard De Geer in a short
excursion on which he guided me to a series of morainelets, if
this term may be used, situated on a tract about three miles
long from east to west and one to two miles wide, lying next
west of the little railway station of Sundbyberg, which is three
miles northwest of Stockholm. Each morainelet there is from
5 to 15 rods wide, and from 5 to 25 feet high above the adjoin-
ing surface, which consists of level cultivated fields of marine
clay, excepting frequent exposures of the granitic bedrocks,
moutonnéed, which are bare on considerable spaces, having
no drift nor boulders, strongly in contrast with the drift knolls
and small ridges of the morainelets, encumbered with their
abundant boulders up to 10 feet or sometimes 20 feet in
diameter. These little moraines, approximately parallel and
traceable more or less continuously from east to west, occur
to the number of eight or ten on the width of about a mile.
If they represent successive years of the glacial retreat, as De
Geer thinks, it had there a rate of about a hundred miles in a
thousand years, which would agree in a general way with the
duration of the Champlain or closing epoch of the Ice age as
estimated from other lines of investigation on both these conti-
nents.

One of the special inquiries which Baron De Geer is now
prosecuting relates to the possible correlation of the intervals
between these morainelets with the probably annual layers of
clay deposition attendant on the withdrawal of the ice-sheet,
observed at many places in southern Sweden nearly as at
Chaska, Carver, and Jordan, in the Minnesota river valley.
With these apparently annual glacial records, he also thinks
that an additional correlation may be afforded by the succes-
sive knolls, widening, or changes in coarseness of material,
which many eskers display at short intervals of their course.

236 The American Geologist. October, 1898

REVIEW OF RECENT GHOLOGICAL
LIQBRATD RE:

Ueber die Verbrettung der Euloma-Niobe-Fauna (der Ceratopygi
halk fauna) in Europa, Von PRoF, Dr. W. C. BROGGER Nyt Mag. for
Naturvidensk, B. XX XV, S. 164-240, Christiania, 18096.

This is a remarkably comprehensive essay treating of the border-
land between the Cambrian and Ordovician systems. Dr. Brogger
takes up in turn the various regions where the fauna of the Cera-
topygi limestone (for which he prefers the name Euloma-Niobe Fau-
na) has been found and compares the forms of this fauna with each
other. In many cases the close resemblance of these regional faunas
has not been evident because the forms have been ranged under dif-
ferent genera by the several authors who have described them. Dr.
Brogger correlates these forms with a master hand and makes a
strong plea for the point he urges, namely the relation of this fauna
to the Ordovician system. He first revises the fauna in Languedoc
described by Munier-Chalmas and Bergeron as follows:

Calymenopsis filacovi becomes Euloma filacovi.

Dictyekephalites villebruni becomes Harpides villebruni.

Amphion escoti is compared to Amphion primigenus Ang.

Ogygia ligniersi Berg. becomes Niobe ligniersi.

Eglina sicardi Berg. becomes Symphysurus sicardi.

Asaphelina miqueli Berg. represents a new genus.

Asaphelina barroisi M-C & B, becomes Dicelocephalina barroisi.
Megalaspis filacovi equals Megalaspides? (s. gen.) filacovi ete.

It has long been known that Salter’s old names for the genera
of the Trunadoc slates needed revision and no abler paleontologist
than Dr. Brogger could have undertaken the task. As a result of
his examination we find the following presentation of the genera:

Niobe homfragi is compared to N. nisignis Linrs.

Platypeltis and Psilokephalus (2 species) is compared to Symphy-
surus incipiens Brogg.

Ampyx parnuntius is compared to A. domatus Ang.

Dikelokephalus furca is compared to Dikelokephalina dicraura
Ang.

Angelina sedgwickii is compared to Parabohinella limitis Brogg.

Conocoryphe, 2 species, is compared to Cyclognathus micropygus
Linrs.

Agnostus dux is compared to Agnostus sidenbladhi Linrs.

Conocoryphe invitus is compared to Apatokephalus serratus Boeck.

C. monile is compared to Euloma ornatum.

C. abditum is compared to Euloma ornatum.

The faunas of Bavaria, of Bohemia, of North America and other
regions, of this age, are similarly treated, and much light thrown upon
the relations of the old genera and the species found in these re-
spective countries.

Review of Recent Geological Literature. 237

The main object of Dr. Brogger’s paper is to show that these types
form a well characterized fauna which he calls the Euloma-Niobe
fauna and which he says should be separated from the Cambrian and
united to the Ordovician faunas, chiefly because the majority of the
genera have an affinity for the genera of the latter system, and that
comparatively few of the trilobites resemble those of the Cambrian
system. At the first blush there would seem to be much to recom-
mend this view, but a similar argument applied to the lower paleozoic
deposit of the Atlantic border region in North America would sweep
even the Arenig or Tetragraptus horizon into the Cambrian as the
Ceratopygi fauna is wanting and the Cambrian types of trilobites are
the only ones found even in the Tetragraptus beds. The question of
the assignment of the Euloma-Niobe fauna is not therefore vital in
this region, but if it prove of more importance than that already
adopted as the base of the Ordovician, viz: the Tetragraptus Fauna,
it should be adopted; a change however would involve the re-arrange-
ment of the collections in many museums as the fauna is now made a
very comprehensive one.

The article is accompanied by two page illustrations showing the
types of the new sub-genera Dikokephalina and Apatokephalus and
a table showing Dr. Brogger’s view of the proper generic reference
of seventy species of the European forms of this fauna. This article,
though dated April, 1896, was not received until the summer of 1808.

(Ce Day i

© Occurrence of Fossil Fishes in the Devonian of Towa. By CHAS.
R. Eastman. lowa Geol. Sur., Vol. VII, pp. 473-488, 1898.

A generation ago great activity was shown in the collection of the
fossil fishes of the Mississippi valley. The wonderful variety of forms,
and the marvelous abundance of remains excited the interest of every
paleontologist. The labors of Newberry, St. John and Worthen will
long be remembered. For more than a score of years, however, the
subject has been allowed to drop almost out of sight, for during this
period practically nothing has been done to advance our knowledge
along this line.

It is, then, with no small degree of pleasure that the recent revival
of the interest in the old ichthyic faunas has been noted. Under the
auspices of the Museum of Comparative Zoology, of Cambridge, Dr.
Charles R. Eastman has, during the past three years energetically set
to work to get together all the accumulated fish remains from the
American Paleozoic, and to study them carefully in the light of the
latest discoveries. His critical papers, giving the results of some of
his special investigations, as a part and preliminary to a greater under-
taking, which is always kept in mind, have appeared with a frequency
and regularity that betokens great enthusiasm, energy and thorough-
ness.

Of the latest contributions that have been issued none is more
instructive than that on the fossil fishes from the Devonian of Iowa.

238 The American Geologist. October, 1898

This memoir is the first of a series dealing with the relationship of
the Devonian and Carboniferous fish faunas. The key-note to their
consideration is contained in the opening paragraphs of Dr. Eastman’s
paper, when he says: ‘The fish faunas of the Devonian and Carbon-
iferous systems present such marked differences as in a measure to
justify the assertion that a great revolution in ichthyic development
took place towards the close of the former period. During the Devon-
ian, the fishes commonly known as Placoderms greatly preponderated
over the Elasmobranchs, which continued to hold a subordinate posi-
tion, both relatively and absolutely, from the date of their initiation
onward. But with the extinction of the Placoderms at the close of the
Devonian, the Elasmobranchs entered upon a new era of development,
increasing prodigiously in point of numbers and variety, attaining
great size, and becoming more formidably armed. In contrast with
the remarkable dearth of Elasmobranchs in the Silurian and Devonian,
upwards of 600 species have been described from the Carboniferous of
this country and Europe; and it is probable that this group of fishes
was much more abundant during the Carboniferous Hen at present
or during any other geologic period.”

The account of the Iowa fishes brings into prominence a newly dis-
covered fauna from the upper Devonian. It was obtained by professor
Calvin from the old state quarries, near North Liberty. “Some of
the teeth bear such close resemblance to those of Carboniferous sharks
that they were first mistaken for them or their allies; but with the ac-
quisition of a larger amount of material very remarkable transitions
were observed between them and undoubted Dipterid species.”’

Incidentally the paper has a direct bearing upon the problem pre-
sented by the typical Kinderhook beds of Illinois and Missouri. The
note records that “An unfinished manuscript lately discovered among
the effects of professor Newberry, and to be issued as a posthumous
publication under the editorship of Mr. Bashford Dean, contains de-
scriptions of two new species of Dipterus from the Chemung group of
Pennsylvania. Mr. Dean was kind enough to compare the originals
with photographs of the new Iowa species, and pronounces them
distinct. The same manuscript also mentions the occurrence of
Ptyctodus teeth in the so-called “Kinderhook beds’ of Louisiana,
Missouri; and it is stated that no differences can be detected between
them and the well-known P. calceolus, which is limited to rocks of
Deyonian age. This is important, for it furnishes additional confirma-
tion of the view contended for, by Calvin and Keyes, that a part of
the formation at Louisiana is unquestionably Devonian.”

In conclusion Dr. Eastman observes that it is “apparent that we
have here to deal with a unique and highly interesting assemblage of
fossil fishes. A number of new Dipnoan genera are encountered, some
of which present astonishing resemblance to primeval sharks, and oth-
ers are connected by gradual transitions with Dipterus. Careful study
of these forms can hardly fail to clear up many difficult problems
affecting Paleozoic fishes. The presence of Dipterus and Arthrodires

Review of Recent Geological Literature. 239

brings the Iowa fauna into relationship with the Chemung and Cats-
kill of Pennsylvania on the one hand, and with the Waverly of Ohio
on the other. Nevertheless the different aspects of these faunas when
compared with one another are very considerable. Through Ptyctodus
calceolus the fauna is related also to the Hamilton of the Mississippi
valley. The abundance of this form, and the absence of all other
Elasmobranchs is a surprising ¢ircumstance. However, it is more
than likely that further search will bring to light many forms which
we should naturally expect to find in rocks of this horizon.”

Some of the further descriptions of the Iowa fishes are contained
in an article by Dr. Eastman, in the American Naturalist for July,
1898 (vol. XXXII, pp. 473-488) in which is considered the Dentition
of the Devonian Ptyctodontide. “Three genera of Paleozoic Chimz-
roids, known only by remains of this dentition, constitute the, at pres-
ent, imperfectly definable family Ptyctodontide. These are Ptyctodus,
Rhynchodus and Paleomylus, distributed throughout the middle and
upper Devonian of northern Europe and North America. The ‘jaws,’
or dental plates as they are more properly called, are rarely well pre-
served, and invariably occur in the detached condition.”

While the bulk of a large amount of the new material came from
the state quarries of Iowa, important collections were obtained near
Milwaukee, Wisconsin. CORKS

Geological Survey of New Jersey, Annual Report of the State
Geologist [PROF. JOHN C. SMOCK] for the year 1S97. Pages xl and
368, with 13 plates, and 25 figures in the text; Trenton, 1808.

.The administrative report, 28 pages, concisely noting the year’s
work, is followed by reports of progress, on the surface geology, by
Prof. Rollin D. Salisbury, in 22 pages, with a preliminary map of the
surface formations of the state; on the Newark system or Red Sand-
stone belt, by Dr. Henry B. Kttmmel, in 137 pages, with a map and
eight other plates; on the Upper Cretaceous formations, by Prof. Wil-
liam B. Clark, in 50 pages; on artesian wells, by Lewis Woolman, 85
pages; on the drainage of the Hackensack and Newark tide-marshes,
by C. C. Vermeule, 19 pages, with three plates; and supplemental notes
on the mining industry, by George E. Jenkins, 41 pages.

Professor Salisbury revises his former nomenclature of the surface
deposits south of the glacial drift area. The Beacon Hill formation
remains of undecided age, late Miocene, or. subsequent. The name
Bridgeton formation is proposed for the early part what was for-
merly called the Pensauken, this name being still retained for the
later part; the Bridgeton beds are regarded as the probable equiva-
lent of the Lafayette; and the Pensauken beds, under their restricted
definition, as correlative with the early Albertan or Kansan glaciation.
Another new term, the Cape May formation, is proposed for the de-
posits of Late Glacial and Early Pestglacial age in the region south
of the direct effects of the ice-sheet and its drainage. This formation
includes the later part of what Prof. Salisbury has before called the
Jamesburg formation; and its earlier part, which is less distinctly de-
veloped, is neglected in the present mapping.

240 The American Geologist. October, 1898

The detailed examination of the Newark system in New Jersey
has been completed, and is quite fully reported; but it is hoped to
present later a more elaborate discussion of some of its problems
when explorations have been extended for comparison beyond the
limits of this state.

Protessor Clark contributes a very interesting summary of the in-
vestigations of the Upper Cretaceous series, as studied by himself
and his associates during the past five years in New Jersey, Mary-
land, and Delaware, preceded by a history of the work of former
observers. Weite

Towa Geological Survey, Volume VIIT:; Annual Report, 1897, with
Accompanying Papers. SAMUEL CALVIN, State Geologist; H. F.
Bain, Assistant State Geologist. 427 pages, with 32 plates, 13 figures
in the text, and six folded geological maps ; Des Moines, 1898.

This volume comprises administrative reports which give brief
statements of the progress of the survey last year, with a summary
of the condition and statistics of production of the mining industries
and quarrying in the state during the year. The aggregate value
of the mineral production was nearly seven and a half million dollars.
Following these reports are papers on the geology of Dallas county,
by A. G. Leonard; of Delaware and Buchanan counties by Prof.
Calvin; and of Decatur and Plymouth counties, and on Properties
and Tests of Iowa Building Stones, by H. Foster Bain.

In Buchanan, Decatur. and Plymouth counties, exceptionally in-
teresting problems have been studied concerning the sequence of
stages or epochs of the Glacial period. The last named county and
adjoining parts of northwestern Iowa are found to present difficulties
in correlating the successive drift sheets and loess deposits with those
of other parts of the state. The evidence perhaps indicates that
northwestward, in the Missouri river basin, the deposition of the loess
continued from the time of recession of the ice border at the end of
the Iowan stage until the time of formation of the Altamont mo-
raine on the margin of the ensuing Wisconsin stage of glaciation.
The Iowan and Wisconsin stages probably occurred very near to-
gether; but they were far later than the even more closely consecutive
Kansan and Buchanan stages, which were doubtless several times
longer ago than the Iowan glacial readvance. WwW. U.

MONTHALY = AUDHORS CARPAL © Gigi
OF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Bain, H. F.

Geology of Decatur county [Iowa]. (lowa Geol. Survey, vol. 8
Pp. 255-309, pls. 21-24, 1 map, 1808.)

*This list includes titles of articles received up to the 20th of the preceding

month, including general geology, physiography, paleontology, petrology and
mineralogy.

Authors Catalogue. 241

Bain; oH. F. ’

The Aftonian and pre-Kansan deposits in southwestern Iowa.
(Interglacial deposits in Iowa: A symposium presented at the Iowa
Academy of Sciences, Des Moines, Iowa, Dec. 28, 1897; pp. 23-38, I
map, 3 pls. Reprinted from Proc. Iowa Acad. Sci., vol. 5, 1808.)
Bainsekis FE.

Geology of Plymouth county [Iowa]. (Iowa Géol. Survey, vol.
8, pr. 315-366, pls. 25-29, 1 map, 1808.)

Bain, Hi F.

Properties and tests of Iowa building stones. (Iowa Geol. Survey,
vol. 8, pp. 367-416, pls. 30-32, 1808.)

Bishop, 1. P:

The structure and economic geology of Erie county [New York].
(15th Ann. Rept. State Geol. of New York, pp. 305-392, 16 pls. 6 maps,
1897.)

Butts, Edward.

Description of some new species of crinoids from the Upper Coal
Measures of the Carboniferous age at Kansas City, Missour:. (Trans.
Acad. Sci. of Kansas City, vol. 1, pp. 13-15, Apr. 12, 1808.)

Calvin, Samuel.

The interglacial deposits of northeastern Iowa. (Interglacial de-
posits in Iowa: A symposium presented at the Iowa Academy of
Sciences, Des Moines, Iowa, Dec. 28, 1897; pp. 1-7. Reprinted from
Proc. Iowa Acad. Sci., vol. 5, 1898.)

Calvin, Samuel.

Geology of Delaware county [Iowa]. (Iowa Geol. Survey, vol. 8,
pp. I19-192, pls. 7-13, I map, 1808.)

Calvin, Samuel.

Geology of Buchanan county [Iowa]. (Iowa Geol. Survey, vol. 8,
pp. 201-253, pls. 14-20, 1 map, 1808.)

Case, E. C.

The development and geological relations of the vertebrates.
Pt. It. Amphibia. Pt. III. Reptilia. (Jour. Geol. vol. 6, pp. 500-
523, July-Aug., 1808.)

Chamberlin, T. C.

The ulterior basis of time divisions and the classification of geol-
ogic history. (Jour. Geol. vol. 6, pp. 449-462, July-Aug., 1808.)
Clarke, J. M.

The stratigraphic and faunal relations of the Oneota sandstones and
shales, the Ithaca and Portage groups in central New York. (15th
Ann. Rept. State Geol. of New York, pp. 27-81, 7 pls, 2 maps, 1897.)
Clarke, J. M.

Notes on some crustaceans from the Chemung group of New
York. (15th Ann. Rept. State Geol. of New York, pp. 729-738, 1897.)
Cum nies Isla 12%

Report on the geology of Clinton county [New York]. (15th Ann.
Rept. State Geol. of New York, pp. 499-573, 5 pls., 1807.)

242 The American Geologist. October, 1898

Eastman, C. R.

Dentition of Devonian Ptyctodontide. (Am. Nat., vol. 32, pp.
545-560, Aug., 1808.)
Elftman, A. H. ;

The geology of the Keweenawan area in northeasten Minnesota.
III. (Am. Geol., vol. 22, pp. 131-149, pl. 7, Sept. 1808.)

Emmons, F.‘H., and G. W. Tower, Jr.

Economic geology of the Butte special district. (U. S. Geol Sur-
vey, Geologic Atlas of the U. S., folio 38, Butte special folio, 6 pp.,
3 maps, 1807.)

Fairchild, H. L.

Glacial geology in America. (Am. Geol., vol. 22, pp. 154-189, Sept.
1808. )

Fineh, J. W.

The basal portions of a continental glacier. A dissertation submit-
ted to the faculty of Colgate University in candidacy for the degree
of Master of Arts. (Pp. 1-38; The University Press, Hamilton, N. Y.,
1808. )

Gilpin Ea ak

Ores of Nova Scotia. Gold, lead, and copper. (Pp. 1-46, 1 map;
Commissioner of Public Works and Mines, Queen’s Printer, Halifax,
1808.)

Goodwin, W. L.

Analyses of corundum and corundum-bearing rock. (Rept. Bu-
reau of Mines of Ontario, vol. 7. pt. 3, pp. 238-2390, 1898.)

Gordon, C. H.

Notes on the Kalamazoo and other old glacial outlets in southern
Michigan. (Jour. Geol., vol. 6, pp. 477-482, pl. 12, July-Aug., 1808.)

Gracey, A. H.

Placer gold on Vermilion river [Ontario]. (Rept. Bureau of Mines
of Ontario, vol 7, pt. 3, pp. 256-250, I map, 1808.)

Hay, OP:

Notes on species of Ichthyodectes, including the new species I.
cruentus, and on the related and herein established genus Gillicus.
(Am. Jour. Sci., ser. 4, vol. 6, pp. 225-232, Sept. 1808.)

Hillebrand, W. F.

Distribution and quantitive occurrence of vanadium and molybde-
num in the rocks of the United States. (Am. Jour. Sci., ser. 4, vol.
6, pp. 209-216, Sept., 1808.)

Jefferson, M. S. W.

The postglacial Connecticut at Turners Falls, Mass. (Jour. Geol.,
vol. 6, pp. 463-472, July-Aug., 1808.)
Kemp, J. F.

Preliminary report on the geology of Essex county [New York].
(15th Ann. Rept. State Geol. of New York, pp. 575-634, 12 pls., 1897.)

Authors’ Catalogue. 243

Leonard, A. G.

Geology of Dallas county [Iowa]. (Iowa Geol Survey, vol. 8, pp.
51-118, pls. 4-6, 2 maps, 1808.)

Leverett, Frank.

The weathered zone (Sangamon) between the Iowan loess and III-
inoian till sheet. (Interglacial deposits in Iowa: A symposium pre-
sented at the Iowa Academy oi Sciences, Des Moines, Iowa, Dec.

28, 1898; pp. 8-17, I map, 1 pl. Reprinted from Proc. Iowa Acad.
Sci., vol. 5, 1808.)

Leverett, Frank.

The weathered zone (Yarmouth) between the Illinoian and Kan-
san till sheets. (interglacial deposits in Iowa: A symposium present-
ed at the lowa Academy of Sciences, Des Moines, Iowa, Dec. 28, 1897;
pp. 18-23. Reprinted from Proc. Iowa Acad. Sci., vol. 5., 1898.)

Luther, D. D.

The stratigraphic position of the Portage sandstones in the Naples
valley and the adjoining region. (15th Ann. Rept. State Geol. of New
York, pp. 233-236, 1 pl., 1 map, 1897.)

Luther D: D.

The economic geology of Onondaga county, New York. (15th
Ann. Rept. State Geol. of New York, pp. 237-303, 20 pls., 2 maps,
1897.)

Martin, G. C.

An occurrence of dunite in western Massachusetts. (Am. Jour.
Sci., ser. 4, vol. 6, pp. 244-248, Sept. 1808.)

Miller, W. G.

Economic geology of eastern Ontario. Corundum and other min-
erals. (Rept. Bureau of Mines of Ontario, vol. 7, pt. 3, pp. 207-238,
6 pls., 1 map, 18908.)

Moses, A. J.

An introduction to the study and experimental determination of the
characters of crystals) Chap. XI. (School of Mines Quarterly, vol.
19, PP. 374-391, July, 1898.)

Packard, A. S.

A half-century of evolution, with special reference ro the effects
of geological changes on animal life. (Science, new ser., vol. 8, pp.
243-257, Aug. 26, 1808; pp. 285-204, Sept. 2, 1898; pp. 316-323, Sept. 9,
1808. )

Reid, H. F.

The variations of glaciers. III. (Jour. Geol., vol. 6, pp. 473-476,
July-Aug., 1898.)

Ries, Heinrich.

Physical tests of the Devonian shales of New York state to deter-
mine their value for the manufacture of clay products. (15th Ann.
Rept. State Geol. of New York, pp. 673-698, 1897.)

244 The American Geologist. _ October, 1898

Ries, Heinrich.

Geology of Orange county [New York]. (15th Ann. Rept. State
Geol. of New York, pp. 393-475, 42 pls., 1 map, 1897.)

Spencer, J. W.

Geological water ways across Central America. (Appleton’s Pop.
Sci. Monthly, vol. 53, pp. 577-503, Sept. 1898.)

Smyth} CG oehie air

Report on the crystalline rocks of St. Lawrence county [New
York]. (15th Ann, Rept. State Geol. of New York, pp. 477-497, 1897.)

smyth; Gilby on:

Report on the tale industry of St. Lawrence county [New York].
(15th Ann. Rept. of New York, pp, 661-671, 1897.)

Tower, G. W., Jr. (Emmons, F. H., and)

Economic geology of the Butte special district. (U.S. Geol. Sur-
vey, Geologic Atlas of the U. S., folio 38, Butte special folio, 6 pp.,
3 maps, 1897.)

Turner, H. W.

Notes on some igneous, metamorphic, and sedimentary rocks
of the coast ranges of California. (Jour. Geol., vol. 6, pp, 483-
499, pl. 13, July-Aug. 1808.)

Udden, J. A.

Some preglacial soils. (Interglacial deposits in Iowa: A sympos-
ium presented at the Iowa Academy of Sciences, Des Moines, Iowa,
Dec. 28, 1897; pp. 39-41. Reprinted from Proc. Iowa Acad. Sci., vol.
5, 1808.)

Udden, J. A.

The mechanical composition of wind deposits. (Augustana Li-
brary publications, No. 1, pp. 1-69, Rock Island, IIl., 1808.)

Upham, Warren.

Raised shorelines at Trondhjem. (Am. Geol., vol. 22, pp. 149-154.,
Sept. 1808.)

Weed, W. H.

Description of the Butte special district. (U. S. Geol. Survey,
Geologic Atlas of the U. S., folio 38, Butte special folio, 3 pp., 3 maps,
1897.)

Whiteaves, J. F.

On some fossil Cephalopoda in the museum of the Geological Sur-
vey of Canada, with the descriptions of eight species that appear to be
new. (Ottawa Naturalist, vol. 12, pp. 116-127, Sept. 1808.)

Whitfield, R. P.

Catalogue of the types and figured specimens in the paleontological
collection of the geological department, American Museum of Natural
History. (Bull. Am. Mus. Nat. Hist., vol. 11, pt. I, pp. i-viii, 1-72,
July 22, 1898.)

Correspondence.

iS)
&
Sal

CORRESPONDENEE.

On THE OCCURRENCE OF CUBANITE AT BUTTE, MONTANA. Ex-
_amination of a brass-yellow mineral that is now being mined for copper
ore on the Speculator and Modoc claims near Butte, Montana, has led to
the conclusion that the mineral is massive cubanite.

Cubanite is a copper and iron sulphide having the composi-
tion of Cu Fe, S,. Its theoretical composition is copper 20.87, iron
36.93, and sulphur 42.24 per cent. Two analyses of this ore made by Mr.
S. J. Gormly, chemist for the Anaconda Copper Mining Company, at
the request of the writer, gave the following results: copper, 25.35,
25.04, iron 34.90, 34,26, sulphur 39.05, 39,90, silica, 0.77, silver, 0.96 0z.,
and a trace of gold. The latter figure in each case is the more accurate.
Other analyses not so reliable, reported to the writer showed I9.8 and
23.6 per cent of copper respectively. The specific gravity is 4.26.

In this analysis the copper percentage is high, being increased at the
expense of the sulphur andiron. This is probably due to the presence
of about 13 per cent. of bornite as a mechanical mixture, indications of

the presence of that mineral having been noticed in the bright and
variegated coloring of cleavage faces and joints.

The uniformity of color, differing from pyrite and chalcopyrite, in
large masses more or less mixed with vein quartz, and the closeness
with which the composition approximates both the analyses given by
Dana, and the theoretical composition, lead to the presumption that the
mineral is of this species though no crystalline forms have as yet been
perfectly identified.

Its occurrence is in a vein which lies just north of a quartz porphyry
dike, and parallel with it. It comes from the depth of about 200 feet.

So far as the writer is aware this is the first cubanite locally reported
in the United States. Horace V. WINCHELL.

Butte, Mont. Aug. 9, 1898.

DRIFT FORMATIONS OF LONG ISLAND.—I have referred so often to
the drift formations of Long Island in the American Geologist that I
feel somewhat reluctant to call the attention of its readers again to
the same subject. Some remarks, however, made by Prof. Salisbury
in the Journal of Geology on certain criteria of stratified drift de-
posits, which have only recently come under my notice, seem worthy
of further remark. He says truly: “It is evident that the stratified
drift may alternate with unstratified many times in a formation of
drift deposits during a single ice epoch.” I had some photographs
taken to illustrate this very point along the terminal moraine in the
city of Brooklyn. On the corner of St. Marks and Utica avenues
where the altitude is about 160 feet above the level of the sea the
complexity of the drift is very marked. Facing St. Marks, north side
of the ridge, the stratification was exceedingly complex in character,
the layers showing very much contortion, while just around the
corner on Utica avenue facing west very little modification was visible.

246 Lhe American Geologist. - October, 1898

Below the so-called englacial till there was a coarse layer of par-
tially stratified material and along the edges of the excavated section
there were some signs of modification. On the northwest corner of
the same avenue below the surface till, the whole mass seemed to be
composed of stratified sand and gravel.

The moraine is very much broken along this section, as during fie
eiacial floods there were many currents that flowed southward from
the Wallabout depression and other basins on the north side of the
island. The gaps in the ridge known as the “clove road,” ‘“Hunter’s
fly,’ and the historic “Jamaica pass” are all in this vicinity.

The point I desire to make, however, is this: The terminal moraine,
which is supposed to mark the southern limit of the great continental
ice-sheet, is more complex in character than the southern series of
hills sometimes spoken of as “moraines of recession.’ This would
hardly bear out Frof. Salisbury’s suggestion that, ‘““The exposed por-
tions of the formation made by the ice-sheet which reached the greatest
extension (the Kansan) should possess less complex contortion of
stratified drift than the drift of the regions farther north which was
affected by two or more ice-sheets.”

It is true that the secondary moraine on Long Island shows a
greater amount of stratification, but as stated, it is less complex in
character than the southern moraine known as the backbone of Long
Island. The reason for this, I have tried to explain in my ‘Ups and
Downs of Long Island.’”’* The glacial or subglacial rivers seem to
have been more united and powerful on the north side of the island,
for on leaving the bay depressions the streams became divided and
ramified in such a way as to produce the diversity of drift along the
line of the terminal which has generally been referred to as unmodi-
fied drift. While it is true that the southern ridge shows less signs
of stratification than the northern series of morainic hills, it is never-
theless a fact, that the former contains a more complex modification.
This modification takes place only along the old lines of drainage
which are generally marked by a profusion of kettle holes, and mar-
ginal kames, as the late Prof. Carvill Lewis called them.

Prof. Salisbury in his remarks already referred to, says: “It is
to be borne in mind, that the ice in many places doubtless destroyed all
the stratified drift deposits in advance of the territory which it occu-
pied later, and that in others, it may have left only patches of once
extensive sheets. It also makes it clear that the relationship of the
two sets of drift are on the whole less commonplace than they might
have been, had all the deposits once made by the ice and its accom-
panying water, escaped decaption.”’ The professor’s theory is made
to favor the duality of the ice age; but if the latter has to depend
upon such arguments for support it has a very slender basis. I must
say, however, that no writer has so well described the different criteria
of the Long Island drift eenOsy as I have observed them, although

*Am. Geologist, March, 1895, vol. XV, no. 3.

Correspondence. 247

Prof. Salisbury has doubtless studied them in a more distant field;
and it has been very encouraging to the present writer as a layman
to find his views so often confirmed by more learned authorities. It
is only by comparing views and observations made in widely sepa-
rated sections of the country, that correct solutions of the many
perplexing problems can be arrived at.

I write in no captious spirit. My only desire is to aid in reaching
the truth and that the cause of science may be somewhat advanced.

Eastport, L. I., N. Y., August ro, 1898. JoHN Bryson.

BISON LATIFRONS AND Bos ARIZONICA. In my recent paper upon
the remains of a Species of Bos in the Quaternary of Arizona reference
should have been made to the important monograph by Dr. Allen upon
the living and extinct American Bisons.* The reference is especially
important inasmuch as Dr. Allen describes two large and perfect horn-
cores from Adams county, Ohio, presented by Dr. O. D. Norton to the
museum of the Nat. Hist. Soc. of Cincinnati, which cores, in size, shape
and general proportions closely resemble the cores from Arizona. Ex-
cellent figures are given from a photograph about one-fifth size.. The fol-
lowing are the dimensions, or measurements, of these cores :

Measurements of the Adams Co. Ohio Horn Cores.

Length of the Upper or concave side........32. inches or 813 mm.

Length of the lower or convex side...........84 inches or 853 mm.

Ciremmference at the base. ...... Toute ae 20 inches or 510 mm.

Circumference 10 inches from the base...... 16 inehes or 407 mm.

Circumference 14 inches from the base...... 14% inches or 368 mm.

Circumference 24 inches from the base...... 9% inches or 24) mm.
e

The width of the skull between the horn cores is estimated to be 16
inches or 407 mm.

Allen observes that “the remains of the larger extinct bisons so far as
yet known are not only few in number but come from not very widely
separated localities, and that the great deposits of bones found at the
Kentucky salt licks, especially that of Big Bone Lick, have yielded, thus
far, no remains that have been identified as belonging to this gigantic
representation of the ox tribe although containing the remains of Masto-
don, Elephant, Megalonyx and Mylodon, together with those of the fos-
sil horse, the great extinct musk-ox, the lesser extinct bison, the extinct
peccary, the caribou and the moose.”

The remains from Ohio, Nebraska and Arizona indicate a much wider
distribution of the gigantic animal than was known at the time of publi-
cation of Allen’s monograph. Inthe map indicating the geographical
range of the bison the area does not extend as far as the Arizona line.

While Europeans generally have referred the American remains of
the extinct bos and bison to Bison priscus of the old world it was the
opinion of Dr. Allen. and it is apparently well sustained by the later dis-
coveries, that the remains indicate an animal so immensely superior in

*American Bisons Living and Extinct, Memoirs, Mus. Comp. Zoology, Cambridge,
IV. No. 10, 1876. An addendum containing a reference to this monograph reached
the publishers too late to be incorporated in this article.

248 The American Geologist. October, 1898

size to the Bison priscus of the old world as to leave little reason for
questioning its distinctness.

For notes on the Osteology of Bison antiquus, and a comparison of
the remains of B. antiquus and B. latifrons, reference may also be made
to a memoir by Alban Stewart*in which he discusses the wide geograph-
ical distribution of B. antiquus, showing that the animal had a range
over the greater part of North America.

Wn. P. BLAKE.
Tucson, Artz. and Mill Rock,

New Haven, Ct.

GEOLOGY AND GEOGRAPHY aT THE AMERICAN ASSOCIATION MEETING.

The meeting of the American Association for the Advancement of
Science, held in Boston, under the presidency of Prof. F. W. Putnam,
on August 22d to the 27th of this year, the fiftieth anniversary since
the formation of this Association, was one of the most interesting and
successful in its history. The enrolled attendance was 903, represent-
ing thirty-five states, the District of Columbia, Canada, Brazil, Great
Britain, France, New South Wales, and Japan. The number of new
members elected was 273, bringing the membership up to about 1,900.
The number of papers presented was 443, of which 55 were read in
the sessions of Secticn E (Geology and Geography), as_ hereafter
noted. ;

By the invitation of Section E, meetings of the Geological Society
of America and the National Geographic Society were held with this
Section, the former in three sessions on Tuesday forenoon, afternoon,
and evening, August 23rd, and thé latter on Thursday afternoon, the
25th. These sessions, and those of Section E, were held in the lec-
ture room of the Boston Society of Natural History, excepting the
final session on Friday forenoon, which was held in the geological
lecture room of the Museum of Comparative Zodlogy, in Cambridge.

The address by the vice president of Section E, Prof. Herman L.
Fairchild, of Rochester, N. Y., on “Glacial Geology in America,”
was presented on Monday afternoon. It is published in the September
issue of this magazine.

Another address of much interest to geologists was given by Prof.
A. S. Packard, of Providence, R. I., vice president of Section F
(Zoology), entitled, “A Half-century of Evolution, with Special Ref-
erence to the Effects of Geological Changes on Animal Life,” pub-
lished in Science for August 26th and September 2d and oth.

Excursions for geological observations were made in the vicinity
of Boston, Salem, Braintree, etc., under the guidance of Profs. W. O.
Crosby, G. Hi. Barton, and J/\E. Wolff, andor ji iiessears eave
Grabau, and others.

In the opening session of Section E with the Geological Society,
on Tuesday forenoon, short memorial addresses on the life and work
of the late Prof. James Hall were given by Profs. Emerson, Fairchild,

*Kan. Univ. Quar., Vol. VI, No. 3, July, 1897, Series A, p. 127.

American Association Meeting. 249

and Niles, and by Dr. Horace C. Hovey, noting Hall’s earnestness
in boyhood and youth to acquire knowledge of geology and allied
sciences, walking twenty miles from his home in Hingham, Mass.,
to attend lectures by Benjamin Silliman before the Boston Society of
Natural History, his distinguished service of more than sixty years
on the Geological Survey of New York, and his recent illness and
death August 7th.

The papers presented before the Geological Society of America,
with brief notes of their scope, mostly as stated in the Society’s pre-
liminary announcement, were as follows:

1. Some Features of the Drift on Staten Island, N. Y. By
ArtTHurR Howick, Columbia University, New York City. The
terminal moraine crosses Staten Island from Fort Wadsworth at the
Narrows to Tottenville, opposite Perth Amboy, N. J. Its front rests
partly upon the serpentine ridge and partly upon the plain region to
the south. In the former locality it consists of true morainal material
of the northern drift. In the latter it comprises a ridge or core of
Cretaceous and Tertiary clays, sands and gravels shoved forward and
upward from their original position on the island, and on top of these
disturbed beds are the morainal till and gravel. At two localities there
are well defined indications of extra-morainic drift, south of the ter-
minal moraine. The direction of glacial movement is indicated by
the strie on rock outcrops to be about S. 17° E. The most abund-
antly represented bowlders are those derived from the Triassic of
New Jersey, although nearly all the outcrops between Staten Island
and the Adirondacks have contributed. A list of about 120 Paleozoic
fossils obtained from the transported bowlders was appended to this
paper with another list of about 35 Cretaceous and Tertiary species,
mostly fossil plants, derived from the disturbed Staten Island strata.

2. Loess Deposits of Montana. By Prof. N. S. SHaLER, Cam-
bridge, Mass. (Read by title.)

3. Glacial Waters in the Finger Lake Region of New York. By
Prof. H. L. Farrcuizp, Rochester, N. Y. This paper noted the
stages of glacial retreat and consequent changes of drainage by which
the glacial lake Newberry, outflowing southward to the Susquehanna,
was succeeded by lake Warren, about 100 feet lower; and this, when
the ice was further melted back, by lake Iroquois. For the most defi-
nite stage between lakes Warren and Iroquois, represented by a large
beach at Geneva, N. Y., and by an old channel of eastward outflow
south of Syracuse, the name lake Dana is proposed.

4. The Stratification of Glaciers. By Prof. “Harey -E'.) Herp,
Baltimore, Md. Lantern views of the glaciers of Switzerland and
Alaska were displayed, attention being directed to the author’s ob-
servations of the persistency of the original stratification occasioned
by the snowfall of successive years on the névé. This structure was
distinguished from the transverse blue banding, analogous with cleavy-
age, which is occasioned by pressure of the moving ice, being especially
developed in constricted or very steep parts of the glaciers.

250 The American Geologist October, 1398

5. Evidences of Epeirogenic Movements Causing and Terminat-
ing the Ice Age. By Warren Upnuam,: St. Paul, Minn. The ver-
tical amount of the preglacial elevation of North America, during late
Tertiary and early Quaternary time, is shown to have ranged from
3,000 to 5,000 feet, according to the soundings of fjords and submerged
valleys on our Atlantic, Pacific and Arctic coasts, the deepest of these
valleys, exceeding 5,200 feet, near Monterey, California, having been
described by Davidson a year ago. Similarly it is also known that a
general uplift of western Europe and western Africa took place at or
near the same time, of varying amount from a minimum of probably
about 1,500 feet in the British Isles to maxima of about 4,000 feet in
Scandinavia, nearly 9,000 feet in the country adjoining the southeast
part of the bay of Biscay, and more than 6,000 feet at the mouth of
the Congo. These great uplifts are thought to have given the cold
and snowy climate under which the ice-sheets were amassed. But
the lands were afterward depressed, in the closing or Champlain
epoch of the Glacial period, to levels mostly somewhat below their
present hights, whereby a temperate climate, with warm and even
hot summers, was restored on the borders of the ice-sheets, melting
them gradually from the periphery inward. Steep frontal gradients
and vigorous glacial currents were thus produced, heaping much of the
drift in prominent recessional moraines.

6. Clayey Bands of the Glacial Delta of the Cuyahoga River at
Cleveland, O., Compared with those of the Implement-bearing De-
posits of the Glacial Delta at Trenton, N. J. By Prof. G. FREDERICK
WriGHT, Oberlin, Ohio. A year ago Profs. Wright, Hollick, Mer-
cer, and Libbey, made excavations at Trenton in the field where
Mr. Ernest Volk has been working under the direction of Prof.
Putnam. As a result of their work, they found several implements
from three to four feet below the surface, and beneath certain red
clayey bands which they supposed to be a part of the original delta
deposited at Trenton during the close of the Glacial period. In the
meetings of the American and British Associations, however, at De-
troit and Toronto last year, vigorous efforts were made by others
to prove that these clayey bands do not belong to the original water
deposition, but may have been wind-blown surfaces or lines of oxida-
tion in the sand. During the past year Prof. Wright has made nu-
merous observations upon excavations in a similar delta of Glacial
age at Cleveland, where he finds a succession of reddish clayey bands
in the sand precisely similar to those at Trenton; and at Cleveland
they merge into cross-bedded sand and gravel on the same level, show-
ing unequivocally that the whole is a water deposit, and that it has
not been disturbed since the original deposition. This strongly con-
firms the inferences drawn a year ago concerning the age and undis-
turbed character of the deposits at Trenton from which Mr, Volk has
derived so many implements for Prof, Putnam, indicating that men
were present, making, using, and losing these implements at the time
of departure of the ice-sheet.

Amencan Association Meeting. 251

7. The Middle Coal Measures of the Western Interior Coal Field.
By H. Foster Batn and A. T. LrEonarp, Des Moines, Iowa.
The lower coal measures of the western interior coal field are marked
by non-persistence of strata. The upper measures are more regular.
Between the two is a series partaking of some of the characteristics
of each. This series includes the Raccoon River beds, the Appanoose
formation and equivalents in Iowa; the Henrietta in Missouri; and
the Oswego and Pawnee limestones of Kansas. No fitting general
term for the whole has yet been proposed. The old term, middle
coal measures, included the beds here referred to and the higher beds
now quite generally known as the Pleasanton shales.

8. The Principal Missourian Section. By CHARLES R. Keyss,
Ces Moines, Iowa. The previous classifications of the Carboni-erous
formations of the region west of the Mississippi river were briefly out-
lined. The results of the recent work along the Missouri river were
summarized, ard the inferences to be drawn were given. The Mis-
sourian series, as one of the four principal subdivisions of the Car-
boniferous of the continental interior, was described. Eleven well de-
fined formations or stages are shown to have a wide distribution, the
formations in five states being correlated.

9g. Tourmaline and Tourmaline Schists from Belcher Hill, Jeffer-
son County, Colorado. By Horace 8B. Parron, Golden, Colo.
Black tourmaline, often in fine large crystals, occurs very abundantly
in pegmatite veins that cut the crystalline schists of the foot-hills of
Jefferson county, west of Denver; Colorado. On the Belcher Hill
road near Golden the tourmaline occurs (a) in separate crystals; (b)
in black masses (schorl) in quartz veins; (c) the same in pegmatite
veins; and (d) in finely disseminated needles replacing biotite and
even feldspar and quartz in biotite schists and gneisses at contact with
veins of pegmatite and quartz. The beautiful banding and cross-band-
ing produced by this replacement is unusual. The paper was illus-
trated by specimens and photographs.

10. Magmatic Differentiation in the Rocks of the Copper-bearing
Series. By AtrrepD C. Lank, Houghton, Mich. In many of the
effusive sheets a difference may be noted between the top and the
bottom. At the top the feldspar is oligoclase, at the bottom labra-
dorite. At the top olivine is more conspicuous, at the bottom augite.
The oligoclase and olivine were evidently formed before the lava from
which the sheet was formed came to rest, at least in part. The
augite and labradorite were probably formed later. It is possible that
the early formed oligoclase rose to the top, and that the sodiferous
magma there formed had not so corrosive action on the olivine as the
calcareous magma left below, which latter may have corroded the
olivine and out of it formed augite. Comparing different flows, we
find the same kind of relations that exist between the top and bot-
tom of the same flow. This suggests that similar differentiation went
on before eruption.

252 The American Geologist. October, 1898

11. The Volume Relations of Original and Secondary Minerals
in Rocks. By Prof. CHartEs R. Van Husk, Madison, Wis. This
paper discusses the volume relations of secondary minerals as com-
pared with original minerals, and considers this volume change in
reference to the depth at which the alteration occurs.

12. Note on a Method of Stream Capture. By Atrrep C.
Lane, Houghton, Mich. When the divide between two streams is
porous, and the valley of the one is much deeper than the other,
springs may arise on the side of this deeper valley, which drain the
water from the higher valley and thus diminish the erosive capacity
of the stream therein, until the higher valley has a stream only in
times of rain, and is soon eaten into by lateral tributaries of the deeper
stream. Various illustrations of this action were given; and it was
noted that during the Glacial period the streams draining the ice-
front were especially liable to capture, because they occupied channels
heavily filled with porous gravel and sand.

13. The Development cf the Ohio River. By Prof. WrtL1am
G. Tieut, Granville, Ohio. A brief review of the literature shows
that the generally accepted view has been that the Ohio river is a
very ancient stream; but recently the work of several geologists in
New York and Pennsylvania indicates the Pleistocene origin of the
Ohio above New Martinsville. In papers already published by the
author the existence of a very ancient erosion basin extending in
general from east to west through the central part of Ohio and In-
diana is established by the restoration of many tributary drainage
lines and by deep wells. Further evidence is presented in this paper
to show that the Ohio in its present location has been established
through the appropriation of sections of numerous northwardly and
northwestwardly flowing streams by the cutting of the ancient cols
and the broadening and deepening of the valleys. The explanation for
these changes is found in the position and action of the ice-sheet in the
various sections, thus determining also the age of this part of the
Ohio valley to be Glacial or Postglacial. The lines of discharge
of the glacial waters determined the present lines of southwardly
flowing tributaries of the Ohio. The preglacial drainage lines of the
Ohio basin were intimately related to many features in the develop-
ment of the Alleghany plateau and the great Appalachian valley and
to the erosion basins in which the great lakes are found.

The theory is proposed that the development of the Ohio river
almost entirely beyond the greatest extent of the ice-sheet, and the
development of the Missouri almost entirely within the limits of the
ice, were due to the different angles which these streams made with
the advancing ice-front, and to their different gradients. In the Ohio
basin the water was forced over distant cols; but in the Missouri basin
it was drained southeastward along the ice-front, thus wearing back
the ice at the time of final recession before the establishment of the
channel by erosion.

American Assoctation Meeting. 253

14. Classification of Coastal Forms. By F. P. GULLIVER, South-
boro, Mass. A scheme is proposed in this paper for the classification
of the various forms of the coast according to their stage of develop-
ment. Two markedly different classes of initial forms are recog-
nized, those following elevation of the land and those following depres-
sion. Each class is seen to have characteristic forms at various
stages of its development, and the writer urges others to think of all
the forms on the coast or along the shore as in a certain stage of
their life-history. This will further suggest the form from which
any given example has come and toward what form it tends to de-
velop.

15. Dissection of the Ural Mountains. By F. P. GuLLIVER.
The Urals are seen to be pretty thoroughly planed, so that the sum-
mits of the many ridges rise to nearly the same elevation, except a
few commanding peaks which are found to consist of quartzyte
or other rock more resistant than the surrounding beds. The summit-
level plane descends gradually to the west until it merges into the
upland levels of the great plain of Russia, while on the east in several
places there is a rather steep fall-off to the Siberian plain, though in
other places the plane of the summits merges into that of the great
Tertiary deposits of northwestern Asia.

Planation in general was then taken up, and distinctions were
sought between planed surfaces formed in three ways: first, those
formed by rivers wearing down the land to baselevel; second, those
produced by the attack of the sea upon a stationary land-mass; and
third, abrasion surfaces resulting from sea attack on a slowly sinking
land-mass.

The stages of dissection in various parts of the Ural mountains,
and the grade-plains of different streams, were compared; the re-
sult of such comparison being that there seem to be three epicycles
or divisions of the present cycle of erosion. (Illustrated by lantern
slides.)

16. Note on Monadnock. By F. P. Gutttver. The relation
of Monadnock to the New England upland was considered, and the
valleys in the vicinity of this mountain were described. The eleva-
tions of two former stream grades have recently been determined in
this region. ,

17. Spacing of Rivers with Reference to the Hypothesis of Base-
leveling. By Prof. N. S. SHater, Cambridge, Mass. (Read by
title.)

18. The Continental Divide in Nicaragua. By C. Wittarp
Hayes, Washington, D. C. The comparatively short streams, with
steep gradients, descending to the Pacific, have in numerous in-
stances increased their drainage basins by capture of the headwaters
of streams flowing eastward to lake Nicaragua and the Caribbean
sea. In this way the water divide on the surveyed line for the Nic-
aragua canal has been removed a considerable distance eastward, being

254 The American Geologist. October, 1598

now at a much lower altitude than the original mountainous water-
shed.

In the session of the National Geographic Society with Section E,
the following papers were presented:

1. The Venezuela-British-Guiana Boundary Dispute. By Dr.
Marcus Baker, Washington, D. C.

2. Considerations Governing Recent Movements or Population.
By Jonn Hyp. Washington, D. C.

3. Some New Lines of Work in Government Forestry. By
GiFForD PincHor, Washington, D. C.

4. The Development of the United States. By W J McGezs,
Washington, D. C.

5. Atlantic Estuarine Tides. By M. S. W. JEFFERSON.

6. The Forestry Conditions of Washington State. By HEnry
GanneET?I, Washington, D. C.

7. The Five Civilized Tribes and the Topographic Survey of In-
dian Territory. By CHarues H. Fircu, Washington, D. C.

8. Bitter Root Forest Reserve. By Ricsarp U.. Goops;
Washington, D. C.

It is expected that several of these papers will be published in the
National Geographic Magazine.

The papers of Section E were as follows:

1. Outline Map of the Geology of Southern New England. By
Prof. B. K. Emerson, Amherst, Mass. This paper, with maps, gave
a summary of the areal geology of Massachusetts, Rhode Island, Con-
necticut, and parts of New Hampshire, Vermont and New York.

2. Basins in Glacial Lake Deltas. By Prof. H. L. Faircuip,
Rochester, N. Y. During the glacial recession, the impounded high
waters of the Canandaigua valley, in central New York, at one time
escaped across the eastern border of the basin into the Flint creek
valley, which was also occupied by a glacial lake at a lower level. The
river thus formed cut a channel in drift and rock, and deposited the
debris, as a delta, at its mouth in the lower lake. The delta now
forms a conspicuous plateau of gravel 125 above the village of
Potter. In this plateau is an irregular depression which reaches to
the very base of the delta deposit, and occupies perhaps one-fourth of
the area of the plateau. The only satisfactory explanation of its origin
is that an isolated block of ice was left here by the receding ice-front,
and that the delta material was piled around it, the subsequent melting
of the ice block producing the cavity. Elsewhere shailow basins oc-
curring in deltas are in many cases attributable to deficient filling by
capricious currents and wave action; but such bowls cannot be con-
founded with the Potter kettle-hole, whichwas illustrated by a map
and photographs.

American Association Meeting. 255

3. An Exhibition of the Rare Gems and Minerals of Mt. Mica.
By Dr. A. C. Hamurn, Bangor, Maine. (Read by title.)

4. The Hudson River Lobe of the Laurentide Ice-sheet. By Prof.
C. H Hrrcucock, Hanover, N. H. The drift and striz of Quebec,
New England, and New York, prove the existence of a glacial lobe
following the Champlain-Hudson valley. The movement was to the
southeast over the summits of the White and Green mountains and
to the southwest over the Adirondacks, but due south along the medial
valley. Last October the author climbed Orford mountain, which
rises northwest of lake Memphremagog to an altitude of about 5,000
feet above the sea, and found it glaciated from bottom to top, wholly
in a southeasterly course. All over the mountain were found boul-
ders of Laurentian gneiss, which (according to their determination by
Prof. Frank D. Adams of Montreal) must have come from the north
side of the St. Lawrence river. It had before been shown that the
highest mountains of New Hampshire and Vermont were glaciated
from the northwest, but doubt had been lately expressed about Or-
ford mountain. These observations prove that the Laurentide ice-
sheet overrode all these mountains, flowing from the region north
of Montreal and Quebec southward and southeastward to the sea
border.

5. The Age of the Amboy Clay Series as indicated by its Flcra. By
ArTHUR HOLLICK, Columbia University, New York City. Inves-
tigations in the paleobotany of the Amboy Clay series of New Jersey
and the equivalents on Staten Island, Long Island, Block Island,
and Martha’s Vineyard, conducted during the past twenty years by
the late Dr. J. S. Newberry, Dr. Lester F. Ward, Mr. David White,
the writer, and others, have shown that the formation which includes
them is very closely related to the Atane and Patoot beds of Green-
land, the Dakota group of the west, the Albirupean series of the
south, and the Cenomanian of Europe, so that there was no hesita-
tion in declaring them all to be Middle Cretaceous in age. This con-
clusion seemed to be quite generally accepted, and was apparently
not questioned until about two years ago, when an announcement
was made, with some show of authority, that the series is probably
Jurassic in age. In regard to the correlation of the several formations
previously mentioned there can be no question. The large amount
of paleobotanical material available for comparison has given oppor-
tunity for the identification of so many species common to them all
that this conclusion is not only justifiable but inevitable; and the only
question is whether this correlation also demonstrates that the sev-
eral formations are Middle Cretaceous in age. If any one of them
is, then they all are; if any one is not, then the others are not.

In paleobotany, as in paleozoology, the broad general facts are
recognized that the biological sequence is coincident with the geolog-
ical sequence, and that the further back in geologic time the simpler
and lower in the scale of life were the organisms. Hence if we divide

256 The American Geologist. October, 1898

our fossil flora into three great classes of cryptophytes, gymnosperms,
and angiosperms, the sequence of their appearance and periods of
maximum development would be in the same order. The percentages
of these classes in any floras should therefore be a fair indication of
the relative ages of the floras. A typical Jurassic flora, such as that
of Siberia, contains, roughly, the following percentages: cryptophytes,
22; gymnosperms, 74; and angiosperms (?), 4. The older Potomac
flora, which is regarded as lower Cretaceous, contains the same classes
in the percentage of 39, 39, and 22; the newer Potomac, regarded as
Middle Cretaceous, 8, 13, and 79; the Amboy clays, 6, 13, and 81;
the Dakota group, ft, 5, and 94. Similar examples. of percentages
were also calculated for other floras regarded as Cretaceous in age.
The main fact, which is at once seen, is the manner in which the per-
centages of the gymnosperms and angiosperms are reversed. Few
angiosperms, and only those of a doubtful character, have been found
in any formation recognized as Jurassic; so that when it was ascer-
tained that in the Amboy Clay flora and its, equivalents the angio-
sperms represent from 70 to go per cent. of the entire flora, there
was little hesitation in considering it as well advanced in the Creta-
ceous period. There would be nothing inconsistent in regarding the
lowest of the older Potomac strata as Jurassic, but even there it would
require definite paleontologic evidence, while in regard to the Amboy
Clay series it is safe to say that a Jurassic fauna will never be found
in connection with its flora.

*« In face of the direct evidence of the fossil flora, therefore, it would
seem a very hazardous undertaking, without ample evidence in re-
buttal, to draw the line of separation between the Jurassic and Creta-
ceous so that in the west the base of the Cretaceous would be rep-
resented by the Dakota group and in the east by the clay marls of the
Matawan formation. (The paper was illustrated by tables of per-
centages and charts.)

6. Some Feldspars in Serpentine, Southeastern Pennsylvania. By
Prof. T. C. Hopxrns, State College, Pa. Feldspar occurs in this
district as dikes or veinlike masses in serpentine, sometimes attaining
a thickness or width of 20 to 25 feet. The most extensive area is in
Chester county, extending also into Lancaster county; but there is
another area in central Chester county, near the corundum mines.
The feldspar is snow-white to pink in color, and seems to be wholly
orthoclase. Some of the dikes have been exploited to a depth of
60 feet.

7. The Region of the Causses in Southern France. By Rev.
Horace C. Hovey, Newburyport, Mass. Lofty tablelands in the
departments of Lot and Lozére, along the western declivity of the
Cevennes mountains, are known as the Region of the Causses. The
term “Causse” is derived from the Latin word calx, meaning lime-
stone. Some of the finest roads in Europe run along the plateaus,
and occasionally descend into the valleys. But the author’s explora-

American Association Meeting. 267

tion, here noted, led by E. A. Martel, of Paris, left all beaten paths
at the village of St. Enimie, and in canoes followed the winding gorges
of the Tarn for 46 miles, and then by mules, or in carriages, examined
the gorges of the Jonté and Durbais. The Causses vary in hight
from 1,000 to 5,000 feet above the sea, and these gorges are cut
through them somewhat as the grand canon of the Colorado cuts
through the plateaus of Arizona. The cliffs of the river Tarn are
often from 1,000 to 2,000 feet high, and occasionally still higher, and
are brilliantly colored.

The caverns of the region are as remarkable as any in Europe.
There are hundreds of them and of all sizes. Among the large caverns
explored by this party may be mentioned those of the Baumes Chaudes.
These are three in number. From one of them the late Dr. Pruniéres
exhumed 300 prehistoric skeletons, and in another are nine vertical
pits from 40 to 127 feet deep. Another cave destined to become
famous is that of Darjelan, with twenty halls from 65 to 600 feet long,
the lowest of them being 420 feet deep. The author’s party discovered
and explored the Aven Armand, down whose chasm Louis Armand
was the first to go. This vertical pit is 240 feet deep, beyond which
is another 300 feet deep, the total vertical depth being 600 feet by
actual measurement. The descent was made by a series of rope lad-
ders, and was not without its dangers. The stalactitic decoration of
these caves is remarkably fine.

The term “aven” is applied to what we call a “sink-hole,” except-
ing that the avens seem to pass more abruptly into pits or chasms.
They pierce the Causses from the summit to the drainage level, and
are death-traps for animals, whose remains were found below in
various stages of decomposition, and whose bones lie imbedded in
the dripstone. The theory is that every aven has a passageway to the
rivers of the region. That this is often so is proved by the great
springs at the base of the cliffs of the Tarn; but in some cases the
passageways trend away from the streams instead of toward them,
and often they are dry, showing that the drainage must have been
at some remotely ancient period.

Should it be asked why the wonderful region of the Causses has
so long escaped exploration amid a country of ‘high antiquity, the
answer is that these lofty plateaus are barren solitudes, except for the
chalets of wandering shepherds. The gorges and avens have been
objects of dread instead of places attracting visitors. The supersti-
tions of the peasants have also operated to make them shun what a
few tourists now delight to explore. Under the stimulus of the So-
cieté de Spéléologie, the region is being opened to the public, and
it is destined to be resorted to by thousands of tourists when its in-
teresting features become more widely known.

>

8. The Washington Limestone in Vermont. By C. H. Ric#-
ARDSON, Hanover, N. H. This name is proposed by the author for
the more calcareous member of the Calciferous mica schist of Prof.

258 The American Geologist. October, 1898

C. H. Hitchcock. It is for the most part a very dark silicious rock,
the color of which is due to finely disseminated carbon. This forma-
tion, varying from 2,000 to 5,800 feet in thickness, extends from south
to north through Vermont; but its most important development,
economically, is in the townships of Washington and Topsham,
Orange county, where, within the past five years, numerous valuable
marble quarries have been opened in it. The chemical composition
of specimens of the marble from a deep test pit at one of the quar-
ries is very remarkable, no less than eighteen elements having been
detected in its analysis.

g. Fluctuations of North American Glaciation shown by Intergla-
cial Soils and Fossiliferous Deposits. By WaRrrREN UpuHam, St.
Paul, Minn. -From a comparison of our continental drift deposits
with the present retreatal conditions of the piedmont Malaspina gla-
cier in Alaska, it is concluded that the flora and fauna adjacent to the
retiring ice-sheet were nearly like those of the same latitudes to-day,
and that fluctuations of the ice-border to the extent of a few miles,
a few score, or a few hundred miles, at different stages of the ice age,
due to moderate secular climatic changes, more acceptably account
for our interglacial beds, former surface soils and leached subsoils,
than a general departure and renewal of the ice-sheet.

No more surprise need be occasioned by the occurrence of remains of
warm temperate floras and faunas in these beds than we must feel in see-
ing tropical and temperate plants and animals at the foot of the Himalay-
as andthe Alps. These extensive mountain ranges, frigid and largely
snow-covered, doubtless exert as much influence on the climate of the
contiguous valleys and lowlands as could be due to the waning ice-
sheets of North America and Europe, when the Early Glacial high con-
tinental altitude was succeeded by the Late Glacial or Champlain de-
pression of these great areas somewhat below their present level. The
ice-sheet of each of these continents, in its time of retreat, being wasted
by a warm climate at its edge, probably rose to an altitude of 5,000 feet
above the land within 100 or 200 miles back from the ice border, which
therefore might considerably readvance during any series of exception-
ally cool years, with plentiful snowfall.

10. Time of Erosion of the Upper Mississippi, Minnesota and St.
Croix Valleys. By Warren UPHAM. Until the Ozarkian epoch
of great elevation of the northern part of this continent, inaugurating
the Quaternary era, the upper part of the present Mississippi basin,
above the vicinity of Dubuque, appears to have been drained northerly,
according to recent studies by Hershey (Am. Geologist, XX, 246-268,
Oct., 1897). After the Cretaceous marine submergence of the state
of Minnesota, its chief river system probably flowed through the Red
river valley to Hudson bay curing the Tertiary era, being reversed
to take nearly the course of the Minnesota and Mississippi rivers at
the end of that era. The St. Croix river is thought by the author to
have obtained its passage through the rock gorge of the Dalles at

American Association Meeting. 259

Taylor’s Falls, Minn., so late as the Buchanan interglacial epoch, pre-
ceding the Ilinoian and Iowan glacial readvance; and the channel of
the Mississippi from Minneapolis to Fort Snelling, eroded during the
Postglacial period, has afforded to Prof. N. H. Winchell his well
known estimate of that period as between 7,000 and 10,000 years.

11. Supposed “Corduroy Road” of Late Glacial Age, at Amboy,
Ohio. By Prof. G. Freprerick WricHt, Oberlin, Ohio. This
paper detailed the discovery of a series of logs lying side by side as
in a corduroy road, and extending for a distance of 200 feet or more,
which were covered by 30 feet of gravel in which were found the tooth
and tusk of a mammoth, the tusk being ten feet long, twenty-two
inches in circumference at the base, and weighing 155 pounds. The
resemblance to a corduroy road was indeed very striking; but the
appearance of the logs showed that they were driftwood, and had been
buried by the accumulation of the gravel that took place along the
old shore of lake Erie, when, during the closing centuries of the
Glacial period, the water was held up to a level 150 feet higher than
now. The logs and base of the deposit are 140 feet above the lake,
and about four miles back from it, on the banks of Conneaut creek, in
the extreme northeastern corner of Ohio. The gravel was evidently
brought down from the higher lands to the south, near the sources of
the creek, and was deposited with the mammoth remains in a delta
at the edge of this old glacial lake. In connection with this in-
vestigation, it was ascertained that similar deltas of gravel characterize
the margin of the old lake where other streams from the south met
it at various places between this point and Cleveland. Altogether
these observations give a very vivid picture of the rapidity with which
coniferous forests proceeded to cover northern Ohio as the ice melted
back, and of the promptness with which the immense animals of the
time redccupied the territory. Important inferences are also derived,
showing that the period of time during which the water remained at
the high levels of the old ice-dammed lakes was short.

12. Changes in the Drainage System in the Vicinity of Lake On-
tario during the Glacial Period. By Dr. M. A. VeEEDER, Lyons,
N. Y. The paper noted sections of wells in buried river channels
south of lake Ontario, from the Niagara river eastward to the Mo-
hawk valley.

13. Recent Severe Seismic Movements in Nicaragua. By JOoun ,
CRAWFORD, Managua, Nicaragua. Description of a series of earth-
quakes in western Nicaragua, April 29th to May rath of this year, as
reported by the author in this magazine for July (vol. xxii, pp. 56-58.).

14. Another Episode in the History of Niagara River. By J. W.
Spencer, Washington, D. C. This paper is a sequel to one read
before the American Association four years ago on the duration of
Niagara falls. It announces the discovery that while the falls were
receding from Foster’s flats to the locality of the railway bridges, the
fall of the river reached its maximum amount of 4zo feet by the

260 The American Geologist. October, 1898

retreat of the Ontario waters toward the north; and that, during the
later part of this recession of the falls, past the Whirlpool rapids, the
return to the present amount of 326 feet descent was interrupted by
the rising of the level of the lake in the gorge to a hight of 75 feet
above its present level, thus reducing the actual fall of the river to
250 feet. The evidence of this is preserved in the remains of a ter-
race deposit opposite the foot of Foster’s flats and a corresponding
terrace just outside the mouth of the gorge; and these terraces, with
other parts of the shoreline in thé Ontario basin which marks the rise
of the water so as to flood the Niagara gorge, are here named the
Niagara strand. The rising of the waters was occasioned by the lift-
ing of the barrier at the outlet of lake Ontariéd to an elevation 100
feet higher than now. By the subsequent erosion of this barrier,
which was partly composed of drift, the actual fall of the Niagara
waters has been increased to its present figure. The reduction of the
descent of the river is found to be sufficient to account for the shal-
lowness of the channel at the Whirlpool rapids. The narrowness.
of this section is explained by the fact that the youthful Niagara took
possession of a small preglacial valley there, giving greater depth
to the river. It is further probable that the volume of the river was
less at that time, since it is supposed that a portion of the outflow of
the great lakes passed to the Mississippi.

15. The Age of Niagara Falls as Indicated by the Erosion at
the Mouth of the Gorge. By Prof. G. FREDERICK WRriGHT,
Oberlin, Ohio. The late Dr. James Hall early noted the significant
fact that ‘‘the outlet of the chasm below Niagara falls is scarcely wider
than elsewhere along its course.” Clearly this is important evidence
of the late date of its origin, and it has been used by the author and
others in support of the short estimates which have been made con-
cerning the length of time separating us from the Glacial period. A
close examination made by the author this summer greatly strength-
ens the force of the argument, since he found that the disintegrating
forces tending to enlarge the outlet and to give it a V-shape are more
rapid than has been supposed. The depth of the gorge at the outlet,
from the top of the Niagara limestone to the river, is 340 feet. The
thickness of that formation of limestone at the surface is here, how-
ever, only about 4o feet; while the soft Niagara shales underlying
it are from 60 to 75 feet thick. Below there is a stratum of Clin-
ton limestone 30 feet in thickness, and below that a shaly deposit of
70 feet. The Niagara shales at this point have never been covered
by talus; so that they have always been accessible to disintegration
by atmospheric agencies.

Somewhat over forty years ago, a railroad was built along the
face of the eastern side of the gorge, affording an opportunity to ob-
serve the rate of disintegration. All along where a perpendicular ex-
posure was. made, the shale has crumbled away to an extent of sev-
eral feet, and in some places to that of twenty feet. A conservative

American Association Meeting. 261

estimate of the rate of disintegration for the 70 feet of Niagara shales
supporting the Niagara limestone would be one inch a year, with a
probable rate of two inches a year. But at the lowest estimate no
more than 12,000 years would be required for the enlargement of the
upper part of the mouth of the gorge 1,000 feet on each side, which
is very largely in excess of the actual amount of enlargement. Some
of the recent estimates, therefore, which would make the gorge from
30,000 to 40,000 years old, are evidently extravagant, and must in-
corporate some error in their premises. The age of the gorge cannot
be much more than 10,000 years, and probably considerably less.

16. A Recently Discovered Cave of Celestite Crystals at Put-in-
Bay, Ohio. By Prof. G. Freperick WricHr. The principal lo-
cality in America from which museums have been supplied with speci-
mens of celestite (sulphate of strontium) is Strontian island, two or
three miles from Put-in-Bay island, in the western end of lake Erie.
Just as this supply was becoming exhausted, a remarkable fissure was
discovered last winter on Put-in-Bay island which is completely sur-
rounded with very large crystals of this beautiful mineral. The fis-
sure was penetrated in digging a well seventeen feet below the sur-
face, and is large enough to permit the entrance of ten or twelve
people at a time. It is not an ordinary cavern, but apparently is the
interior of an immense “geode’’ lined with celestite crystals. The
geological formation in which it occurs in the Waterlime of the Lower
Helderberg. Large deposits of gypsum occur in the vicinity.

17. Geography and Resources of the Siberian Island of Sakhalin.
By Prof. Bensamin Howarp, London, England. Sakhalin has a
length of about 670 miles and a breadth of from 20 to 150 miles. The
features which the author observed during his visits to the island in
1890 and 1896, as described in this address, are (1) the absence of
natural harbors and reliable anchorages around its entire 1,500 miles
of coast, and the reasons for it; (2) the contrast which this island,
having no volcanoes, exhibits as compared with the volcanic chain
of the whole Japanese group and its continuation in the volcanoes of
Kamtchatka; (3) the contradiction which Sakhalin, possessing an al-
most subarctic climate, affords to the popular belief that latitude is
the dominant factor in the determination of climates; (4) its mineral
resources, especially coal and iron; (5) the immensity and density of
the fish shoals in the neighboring waters; (6) the absence of navigable
rivers; (7) the persistence of unadulterated life and manners in the
aboriginal Ainos there, as when described nearly three thousand years
ago by the oldest Japanese historian; (8) the vast numbers of
medusz (jelly-fish) along the southern coast, and the marvelous
phosphorescence of the sea as observed by the author; (9) the strate-
gic value of the island to Russia; (10) the completeness of its adapta-
tion to its present use as a penal stronghold; (11) the present de-
velopment of its agricultural and mineral resources, and its pros-
pective self-maintenance chiefly from its future fishing industries; and

262 The American Geologist. October, 1898

(12) the expediency of maintaining the spelling of the word Sakhalin,
as here used.

18. Evidence of Recent Great Elevation of New England. By
J. W. Spencer, Washington, D. C. The paper was a descrip-
tion of the valley terraces in mountainous parts of New England, il-
lustrated by sections showing that the declivities of the valleys are not
by even slopes but by a succession of steps, the plains of which be-
come terraces farther down the valley. These steps are regarded as
gradation plains in the changes of the baselevel of erosion, and many
of the corresponding terraces are hundreds of feet above the floors of
the valleys. From these features it is inferred that the recent rise of
the mountainous region can be approximately measured by the sum of
the hights of the steps. Yet it is not inferred that the elevation
need to have been from below the sea level: and consequently the
gravels are not claimed to have been necessarily of marine origin.

19. The Oldest Paleozoic Fauna: By G. F. MarTrHew,
St. John, N. B. This fauna is contained in a series of beds uncon-
formably underlying the Cambrian system in eastern Canada and
Newfoundland. The base of the Cambrian in the former country is
marked by a barren sandstone, and in the latter by conglomerates.
Erosion of the lower terrane continved up to and included the time
of the Paradoxides fauna. The relation of these two terranes is com-
pared to that of the Upper and Lower Silurian in New York or the
Carboniferous and Subcarboniferous in eastern Canada. The fauna
known consists of about twenty species. It contains no trilobites,
either in eastern Canada or Newfoundland. Various forms of the
family Hyolithide are the dominant types. Other gastropods allied
to Capulus and Platyceras occur; also brachiopods; remains of echino-
derms (cystids?); and corals allied to Archeocyathus and Dic-
tyocyathus. The thin limestones which occur in the upper half of the
terrane are supposed to have originated chiefly from foraminifera
(Globigerina, etc.).

20. The Oldest Known Rock. By Prof. N. H. WINcHELL,
Minneapolis, Minn. After allusion to the vague ideas formerly en-
tertained of the rocks now included under the term Archean, and still
surviving in some places, this paper, by a general diagram, presented
the Archean as recently made out by the Geological Survey of Minne-
sota. With a brief description of the other members of the Archean
in Minnesota, the author more particularly described the so-called
greenstones of this state, which he considers the bottom of the
Archean scale and the representative of the original crust of the earth
formed from the molten mass by the earliest consolidation. The
greenstones are divisible into two parts, one igneous and the other
clastic, the latter succeeding the former with a confused and some-
times non-conformable superposition, somewhat as surface eruptive
rocks might be superposed, in the presence of oceanic action, upon a
massive of the same character at the same place. The clastic portions

American Association Meeting. 263

of the greenstones vary to more silicious rocks, constituting great
thicknesses of graywackes, phyllites and conglomerates, and as such
have been converted by widespread metamorphism into mica schists
and gneisses, the alteration coming on by degrees, increasing in
intensity toward centers of granitic intrusion, and toward the great
areas of granite and igneous gneiss.

Such granite and such metamorphic rocks, as a whole, have been
considered the basement rock, the oldest known rocks of the country.
But, following up the long known fact that the Laurentian granite
ard ignecus gneisses cut the schists and sedimentary gneisses and
hence are younger, they are in the same way shown to be younger
than the bottom greenstones. They occasionally penetrate these
greenstones and change them to amphibolyte and pyroxene gneiss.
These metamorphic schists and gneisses seem to be a representative
of the sedimentary portion of the Lower Laurentian of Canada, while
the igneous granite and gneisses are as plainly a general parallel of
the igneous portion of that series. It follows therefore that the Cana-
dian Laurentian is, as a whole, of later date than the greenstones,
if the succession is the same as in the Northwest, and that the
greenstones should be considered the bottom rock of the geological
scale.

21. The Origin of the Archean Igneous Rocks. By N. H.
WiINCHELL. To be published in the American Geologist.

22. Joints in Rocks. By Prof. C. R. Van Hise, Madison,
Wis. (Read by title).

23. Notes on Some European Museums. By Dr. E. O. Hovey,
American Museum of Natural History, New York City. Relating
to administration and display of specimens; to be published in the
American Naturalist.

24. History of the Blue Hills Complex. Byeetor Wee ©:
Crossy, Boston, Mass. The complex of the Blue hills, on the
southern border of the Boston basin, is a small part of the great
granitic bathol ite of eastern Massachusetts, inclosing isolated masses
and belts of Lower and Middle Cambrian strata. The Cambrian beds
are cut by a series of diabase dikes older than the granites. The
granitic seriés, which clearly constitutes one genetically related or
consanguineous group, comprises:

I. Plutonic rocks: 1. Normal granites, forming the main body
of the batholite: (a) biotitic normal granite (granitite); (b) horn-
blendic normal granite. 2. Rocks forming the contact zone of the
batholite: (a) dioryte and basic granite (granodioryte); (b) fine gran-
ite; (c) quartz porphyry, passing into a basic, quartzless porphyry.

Il. Intrusive or dike rocks not occurring as apophyses of the
contact zone :(a) microgranite; (b) aporhyolyte.

III. Effusive or volcanic rocks: (a) aporhyolyte (compact and
fluidal forms).

264 The American Geologist. October, 1898

The Cambrian sediments were first strongly folded and injected
by the pre-granitic diabase; and quite certainly not later than the
early Devonian epochs they were invaded by the great body of magma
from which the granitic series was developed. No trace of the floor
upon which the Cambrian strata were deposited has been discovered
in the region of the Blue Hills complex. It is believed that the gran-
itic magma was, in the main, developed in situ by a great heat invasion
or rising of the isogeotherms inaugurated by deep sedimentation and
greatly stimulated or accelerated by the thickening of the supercrust
by extreme plication and flowage and the transformation of mechani-
cal energy into heat. This heat invasion was sufficient to induce
aqueo-igneous fusion in the lower portion of the hydrated zone,
whereby the pre-Cambrian rocks and a considerable volume of the
overlying Cambrian sediments were absorbed by the plutonic magma.
During the slow refrigeration of the batholite and the solidification of
the magma, it experienced both chemical and textural differentiation;
but the chemical differentiation, whether of the main body of the
batholite or of its contact zone, was practically limited to the great-
est depths and dependent upon a convectional circulation of ‘the
magma, in accordance with Becker’s theory of fractional crystalliza-
tion. In conformity with this view, the contact zone is composed,
at successively greater original depths, of quartz porphyry, fine gran-
ite, granodioryte, and dioryte, each of these contact types passing
gradually downward into the normal granite. After long continued
erosion had in large part removed the sedimentary cover of the bath-
olite, crustal adjustments permitted the extrusion of a part of the
deep-seated and relatively acid magma residuum, forming intrusive
masses or dikes of microgranite and aporhyolyte and effusive masses
or surface flows of compact and fluidal forms of aporhyolyte.

This general theory of the complex closely parallels, at most
points, that proposed by Dr. A. C. Lawson for the complex of sedi-
mentary and granitic rocks in the Rainy Lake region (Geol. Surv.
Canada, Annual Report, new series, vol.iii, 1887-88, F, 139-142).

25. Paleontologyof the Cambrian Terranes of the Boston Basin.
By AmMapEus W. GraBav, Boston, Mass. The Lower Cambrian
rocks are found to contain fossils at Nahant, Mill Cove, Rowley,
Topsfield, and Jeffreys Ledge. The last three localities were dis-
covered by Mr. J. H. Sears, who was also the first discoverer of fos-
sils at Nahant (1887). From collections made by Mr. Sears at Na-
hant, seven species have been identified, including four of Hyolithes.
The fossils detected in the rocks of the other localities consist of
indeterminate sections of Hyolithes, and a cross-section of a trilobite
from Mill Cove. From pebbles and boulders found at Nahant and
Cohasset by Mr. T. A. Watson, a large number of Lower Cambrian
fossils have been obtained, representing fifteen species.

The Middle Cambrian of Hayward’s creek, South Braintree, con-
tains the large Paradoxides harlani, Agraulus quadrangularis, and

American Assocration Meeting. 265

several other forms. The Upper Cambrian is represented in this dis
trict only by erratics containing Lingula and Scolithus.

_ 26. Diamonds in Meteorites. By Mrs. E. M. Souvret.e, Jackson-
ville, Florida.

27. The Periodic Variations of Glaciers. By Prof. Harry F.
Ret, Baltimore, Md. (Read by title). The Journal of Geology,
in its recent issue for July-August, contains an article on this sub-
ject by Prof. Reid (vol. vi, pp.473-476), giving records for Europe,
Asia and Greenland, in 1896, and for the United States in 1897. A
general retreat of the glaciers is noted, excepting a slight tendency
of advance in Greenland.

28. Note on the Occurrence of Tourmalines in California. By
C. R. Orcutt, San Diego, Cal. Near San Diego an enormous
bed or vein of lepidolite (lithia mica), 60 feet or more in width where
best exposed, contains rubellite (pink tourmaline) in large amounts.
As a source of lithia and potash, this deposit must soon take first
rank commercially. It is now being worked as an open quarry, and
1,500,000 tons are estimated to be available. Much of the rubellite has
been distributed to museums. Tourmalines of gem quality were first
found during the present year. Black tourmalines are frequent, but
green tourmalines occur only sparingly at this locality.

29. The Agassiz Geological Explorations in the West Indies. By
Rogert T. Hitt, Washington, D. C. This paper, which, with
several preceding, was presented in Cambridge on Friday forenoon
in the Museum of Comparative Zoology (largely founded through
the labors and munificence of Louis Agassiz and his son, Prof. Alex-
ander Agassiz), described briefly the expeditions made during recent
years by Alexander Agassiz, with his assistants, for observations in
zoology and geology, on sea and land, in the West Indies and on the
isthmus of Panama. Within late Tertiary and Quaternary time, many
parts of this region have undergone great epeirogenic movements,
perhaps more interesting than those of any other part of the world
in such late geologic periods. A brief outline of the geological work
already done and to be done was given, and the conclusion presented
that it would take many years of serious research and study before
final results could be reached concerning the remarkable history of
the region and its relations to continental development,

Dr. J. F. Whiteaves, paleontologist of the Canadian Geological
Survey, Ottawa, Canada, was elected to be the vice president for Sec-
tion E, and Prof. Arthur Hollick, of Columbia University, New York
City, to be its secretary, in the Association meeting at Columbus,
Ohio, next year. Geology is also represented and honored in the
election of Prof. Edward Orton, of Columbus, to be the president of
that meeting. WARREN UPHAM,
St. Paul, Minn., Sept. roth. Secretary of Section E, 1808.

266 The American Geologist. October, 1898
PERSONAL AND SCIENDLPIC NE Vy

Pror. JAMES HALL, STATE GEOLOGIST OF NEW YorK,
died Aug. 7, at Bethlehem, N. H. His long service for the
State of New York has rendered his name familiar to geol-
ogists throughout the world. His activity spanned nearly
two generations, and his impress on geological science
is probably greater than that of any other American geol-
ogist. The State of New York can well afford to honor her-
self by some lasting memorial to his name, in addition to
that which exists in his published works.

Pror. C. H. Hircucock, having leave of absence from
his duties in Dartmouth College, sailed August 25th from
Vancouver, on the steamer Aorangi, to spend a year in geo-
logical exploration i in the Hawaiian Islands. His address
will be Honolulu.

Pror. W. M. Davis, of Harvard University, is also ab-
sent, for a year in Europe, his address being in care of Bar-
ing Brothers & Co., London.

Mr. JAY WoopwortTh, Assistant in Geology, of Harvard
University, returned September 17th, from an absence of
three months in Europe spent in travel for geological ob-
servation, from the Island of Méen, in the Baltic sea, through
Germany, Switzerland, northern Italy, England, Scotland
and Ireland.

THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF
SCIENCE supplied to its members at the Boston meeting the
following handbooks of information: ‘A Handbook of the
Principal Scientific Institutions of Boston and Vicinity, with
a brief account of the more important Public Works, of the
Geology and Geography, and of Places of Historical Inter-
est” (118 pages, with ten views of buildings, from photo-
graphs), prepared by the Local Committee; and a “Guide
to Localites illustrating the Geology, Marine Zoology, and
Botany of the Vicinity of Boston” (100 pages, with maps,
sections, and views), edited by A. W. Grabau and J. E.
Woodman, with contributions by Profs. Crosby, Davis,
Emerson, Farlow and Wolff, and including convenient
bibliographic references. Through the courtesy of the
officers of the Harvard University, Cambridge, the Local
Committee also presented to the members ‘‘A Guide Book
to the Grounds and Buildings of Harvard University” (149
pages, with map and many views of the university build-
ings); and a “Guide to the Peabody Museum” (29 pages).

.
a

‘TITA GtV 1d

‘AM ALY AHOOOHVILVHD AHL NO MATA

‘TIXX “104 ‘ESTVOTONH NVOINGWY AHS,

THE

AMERICAN GEOLOGIST.

Vor. XXII.. NOVEMBER, 1808. No. 5

GEOLOGICAL PHENOMENA RESULTING FROM
THE SURFACE TENSION OF WATER.

By GrorGE E. Lapp, Rolla, Mo.
(Plate VIII.)

The term “surface tension” is the familiar one used by
physicists to denote certain molecular conditions on the super-
ficial film of bodies, where, owing to the absence of cohesive
attraction on the outside, there exists a relatively greater sta-
bility of position among its molecules, with reference to move-
ment outwardly from the mass, and a fendency to diminish
the extent of surface,—a resultant of cohesive forces acting
alone from within.

This contractile tendency of the surface is manifested to us
strikingly by liquids. In the case of water, among its effects
are marked geologic changes, which are accomplished some-
times directly, and sometimes ‘through co-operation with other
forces. They will be discussed or referred to here under the
general headings: Effects produced by Capillarity; Floccula-
tion; and Floating of Materials.

Effects Produced by Capillarity.

Among the most important results are those attained
through the behavior of liquids in minute tubes or fissures:
the phenomena being that liquids, within such tubes, stand,
under certain circumstances, in positions at variance with
those occupied under normal conditions of gravity, or other
influencing forces.

These phenomena are omnipresent, and most important

208 The American Geologist. November, 1898

from a geological point of view, causing the penetration of
water, upwards or downwards, or in any direction, into the
mineral and rock constituents of the earth’s crust, which in the
main have a sufficient attraction for water to produce capillary
phenomena. But under certain conditions the attraction is
wanting and the directly opposite capillary effects are pro-
duced.

The principles of the circulation of water through inco-
herent materials, especially soils, have been comprehensively
discussed by Prof. Milton Whitney, in a paper entitled “Physi-
cal Properties of Soils in their Relation to Moisture and Crop
Distribution,’ and in other publications.*

Little if anything is added here to his observations con-
cerning the movement of water, through soils. Prof. Whit-
ney, however, applies these principles only to the agricultural
question of crops. They may also be considered from a more
general point of view and in connection with other phenomena
of surface tension of water, i. e, with reference to the relation
of moisture in incoherent materials, and the phenomena of
shrinkage on drying, to land vegetation as a whole, and to
erosion. The broad questions may be asked: How far is land
vegetation dependent on capillary waters? To what extent is
the presence of soil-mantles dependent upon the tension on
the free surface of water acting in capillary tubes?

We know that owing to surface tension a movement of
water takes place not only in the more or less incoherent ma-
terials, but in the solid rocks themselves, and in minerals along
cleavage planes, or wherever a rift or crevice appears, to give
play to the necessary forces: Also, that on drying the inco-
herent materials become more or less hard and consolidated.
In studying these phenomena we observe, essentially, edness
of the material, and the continuance of this condition, in case
of loss by evaporation on any surface, as long as water-supply
endures; also that the water is present in minute columns or
sheets, and that a lateral inward pull exists, on the walls of
the rock, varying with the mass of the water suspended in each

*In order to avoid confusion of ideas it is necessary at the
start to conceive these materials in a condition unaffected by the
surface tension of water, i, e., in a ary incoherent state, as if re-
moved from water and dried, particle by particle, or ground or pro-
duced originally in a dry atmosphere.

The Surface Tension of Water.—Ladd. 269

tube. We see further that the effect of this pull may result
in the displacement of material, when the conditions are ful-
filled in clay or rock dust. In this case the movement of in-
dividual particles is accomplished as the mass enters the wet
condition, and a primary shrinkage* ensues, which is followed,
if evaporation is in excess of the water supply, by a secondary
shrinkage, and at least partial consolidation.

Looking upon the average clay as a type of the fine-
grained incoherent rocks, we find it to consist of minute min-
eral particles, most of which are thin, angular scales.

The interstices among these may be regarded as a laby-
rinth of capillary tubes. The particles have a strong attraction
for water, which is absorbed with varying capacities. Such a
substance tends also to elevate water from depths below the
surface, and to replace that which may be evaporated by the
sun’s heat. But when the evaporating process is the dominant
force at work, drying takes place and shrinkage of the mass
occurs. +

Our every-day conception of the drying of clays is so inti-
mately associated with the idea of their consolidation and
shrinkage, that we are accustomed to think of these as one
and the same phenomenon. They are, however, distinct phe-
nomena, the former directly following the application of heat;
the latter indirectly consequent upon it through the influence
of surface tension.

The nature of this process can readily be seen by a com-
parative study of the accompanying diagrams.

Fig. 1 shows the positions of the surfaces of water in a
series of capillary tubes, the walls of which are comparatively
rigid and attract the liquid. The dotted lines indicate the posi-
tions of the surface of the water at successive stages of evapo-
ration.

Fig. 2 illustrates conditions similar to those in Fig. 1, ex-
cept that the walls (a) instead of being rigid are collapsible

*The terms primary, secondary and tertiary shrinkage are used by
the writer in discussing a series of experiments on clay. They refer
respectively to the shrinkage following the application of water to dry
or slightly moist clay, (when in the incoherent state); that following
drying; and that due to the loss of combined water on ignition or
“burning”.

+ This has a lineal value, in extreme cases, of over 35 per cent.

270 The American Geologist. November, 1898

2

and approach each other, as water evaporates, to positions (b),
and so on.

Fig. 3 illustrates a thin sheet of water (a) resting on a
series of capillary tubes, in a vessel (b) for which it has no
affinity. Here surface tension of the water overcomes the
pull of gravity.

Fig. 4 illustrates, diagrammatically, the beginning of the
process with conditions similar fo those in the experiments
to be described on another page, (the vessel having been re-
moved from the water supply).

So long as water could be drawn up from below, while
evaporation was going on above, there would be no change
in the conditions except the gradual movement of water up-
wards, and no necessary movement of the clay particles in any
direction.

When the supply of water is removed, surface tension at
(a) and (b) still operates to elevate water to the original hight.
If there were no points of weakness in the mass, that is, if
the conditions were uniform throughout, and each particle
(c) fixed in its place, there would result, of course, only a grad-
ual subsidence of the water. If the particles, however, be con-
sidered free to move in any direction, uniform as regards their
size, shape and distribution, and if the attraction between
the water and the sides of the vessel be exactly equal to that
between the water and the clay, a vertical shrinkage will take
place.

The capillary attraction capable, originally, of lifting water

The Surface Tension of Water.—Lada. 271

to the points (a), would still be operative, and water, to re-
place that evaporated, would be fed from the channels, the
walls of which are the most easily collapsible, and, with the
given conditions, these would be the lateral ones; the down-
ward movement being facilitated by gravity and presence of
the one free surface above.

It must be borne in mind, that the tension at the points
(a), and beneath them, throughout the process, is of uniform
value in each and every tube.

If, as in the case of our experiment, the attraction be-
tween the clay and the water exceeds that between the
water and the walls of the vessel, a point will be
reached where the up-pulling at (a), between the clay
particles, will remove the water from the columns (b) adjacent
to the sides. The mass is then free to shrink upon itself, in
horizontal as well as in vertical directions. Water is fed to the
exposed surfaces so long as the particles can approach each
other. Shrinkage has been accomplished and a consolidation
results from the bringing of the fine particles into intimate
contact.

When this takes place in nature the lateral tension is un-
able to contract the mass as a whole. Owing, however, to in-
equality of conditions, planes of separation are established
along lines of weakness, and “mud-cracks” result. The smal-
ler masses thus formed may then shrink further.

The finer grained the material, the greater the amount of
surface of the particles, as compared with their mass. Con-
sequently, there are more contacts; mutual attraction and
friction more effective; and the mass more completely con-
solidated. In the case of sand, the mass of the individuals so
far exceeds the amount of surface at which contacts exist,
that the bonds are ineffectual, and the material remains inco-
herent.

The steps leading to these various results may be illus-
trated by certain experiments, made by the writer while inves-
tigating the properties of clays.*

In order to determine the absorbtive power, amount of
shrinkage and degree of consolidation of samples of this sub-

of the Geological Survey of Georgia.

272 The American Geologist. November, 1898

1. A weighed amount of clay, dried at 100° C., and pre-
viously ground to pass through a 100 mesh sieve, was placed
in a brick-shaped tin vessel, the bottom of which was finely
perforated and lined with filter paper, to prevent the escape
of clay. This vessel was then supported in a small tank sup-
pled with water, just high enough to reach the perforated
bottom.

Immediately following the contact of water with the clay,
a marked down-pull of the latter occurred, effecting the pv7-
mary shrinkage of the incoherent mass.

2. The next experiment was the determination of the re-
lative rate of loss of water on drying at 100°C., by weighing at
fixed intervals; and (3) of the amount of shrinkage for each
dimension, by careful measurement at the successive stages
of drying. The shrinkage here involved is that referred to as
secondary.

(4) Other experiments with specially devised apparatus
tested the tenacity of the clays at intervals during drying, be-
ginning with the saturated condition, and ending with the dry
brick, thus determining the degree of consolidation.

These experiments naturally showed results widely vary-
ing among the different clays. A brief summary of the more
important of them follows.

I. The clays absorbed water in amounts varying, re-
spectively, from 40 to over 200 per cent. by weight.

Il. Generally speaking, those, which were originally in-
coherent in nature, absorbed the largest amounts.

Il]. The rate of drying varied directly with the amount
of water absorbed.

IV. The amount of shrinkage varied according to a com-
plex of conditions, such as density, the size and shape of par-
ticles of the clay-base, and their state of aggregation, also
upon amount of sand present, and the size and shape of its par-
ticles:

*The anomalous fact was discovered, that, among clays otherwise
similar, those containing the greatest amount of sand, mm cases as
high as yo per cent., shrank the most. This is noteworthy in view of
the fact that sand is often added by potters and brick-makers, to
diminish the shrinkage of a clay. For the case in hand, however, an
explanation may be found in the fact, that the greater part of this
sand is in extremely minute particles, probably smaller than those
of the clay.

The Surface Tension of Water—Ladd. 273

VY. The percentage of secondary shrinkage varied in dif-
ferent directions, being greatest for the smaller dimensions.
The reason for this being, probably, as follows:

The tendency to establish equilibrium in the mass, due to
the loss of water on an evaporating surface, is not followed
by uniform results, owing to the greater amount of
mass to be moved in the longer direction than in
the shorter. Consequently the movement and shrinkage are
more successful along the shorter dimension. More marked
than this, however, as a cause, is the difference in the resistance:
per unit area of cross section due to the friction on
the contact surface, at the bottom of the brick, along
the lateral and longitudinal directions. A slender pen-
cil of clay can only be dried without breaking, by resting it
on a series of rollers, or some similar device.

VI. The tenacity of the clays varied exceedingly at differ-
ent stages of wetness.

VII. In general, clays diminishing the most in bulk
through secondary shrinkage were, in the dried state, the most
tenaceous. For example, one clay having a maximum shrink-
age in a single direction of about 24 per cent, withstood a
strain of nearly 400 pounds per square inch, while another,
with a maximum shrinkage of less than 8 per cent, withstood
a strain but slightly over two pounds per square inch.

These laboratory experiments explain the nature of many
every-day phenomena in the geological world, where materials
and conditions similar to those of the experiments are so con-
stantly encountered. From their consideration we see that
the most direct effects of surface tension acting as capillarity
in rocks are the wetting and transference of water through
these; shrinkage and consolidation.

What is the relation of these effects to vegetation?

Surface tension operates to retain rain-water at the sur-
face, where it is available to furnish the moisture needed by
plant life, and also to draw up from the “water-table’” below,
supplies to renew that removed by evaporation and the re-
quirements of vegetation. It carries, held in solution, with the
water, the mineral foods which build the tissue and support the
growing plants. It also forms a crust produced through
shrinkage, which retards evaporation.

274 The American Geologist. November, 1898

Prof. Whitney in the introduction to “Some Physical Prop-
erties of Soils,” states that chemical analysis has not explained
the relation of soils to plants or the local distribution of the
latter; that the general distribution of these is determined by
temperature and rain-fall, but the /oca/ distribution, by the
relation of the soils to moisture.

If the statements so far made are true can we not reason
further, and say that without the operation of surface tension
the very existence of land vegetation, or at least the greater
part of it, would be threatened? But for capillarity would
not rain waters escape through, or over, the soils too rapidly
to be available? Would the film of water directly attracted
by each grain of soil succeed in resisting evaporation, and if
it did, how extensively would it support vegetation? Where
would the plant food come from? And another, more funda-
mental, question,—to what extent would the fine-grained ma-
terials, constituting soils, accumulate, and how long would
they rest in one place? In short would land vegetation have
a soil permanent enough to grow in?

From a consideration of the facts it is evident that the ex-
istence of the former, and the permanency of the latter are
largely inter-dependent, and that, besides this, each is directly
dependent (the degree being the only question) on the opera-
tion of the surface tension of water.

If they should dry without the influence of the tension on
the free surface of water, they would dry into incoherent “pow-
der,” ‘‘sand” or “dust,” and no crust, more or less solid, would
be formed. And, on the other hand, if surface tension did not
operate to elevate, in soils, water from below, they would dry
after wetting in a much shorter time.

In the former case soils would be subject to erosion to a
vastly greater extent than they are, owing to the absence of a
crust and the general consolidation shown to result from dry-
ing.

In the latter case the presence of the water obtained by
capillarity renders the soils somewhat tough and coherent, in
a different fashion, and so again tends to retard erosive
agencies.

Thus surface tension acts in two direct ways to preserve
these materials from erosion—by the wind, the impact of rain,
or flowing water. ,

The Surface Tension of Water-—Ladd. 25

Indirectly, it makes possible (7) a growth of vegetation
which further and so largely protects the soil from erosion.
Moreover, this vegetation is a source of chemical decomposing
agents which accelerate soil accumulation—a process further
facillitated by capillary penetration of the solid rock.

The following generalizations, though containing familiar
facts, are grouped together here as an outline of the features
of the circulation of water in soils.*

First—The soils are composed of particles of mineral
matter of different sorts, chiefly quartz, feldspar and clay
(kaolinite), and these occur in sizes ranging from that of
coarse gravel down to minute rock fragments .coor of a milli-
meter in dimater.t They are also of different shapes,—the
quartz grains varying in form from angular to well rounded,
while the clay or kaolinite constituents are commonly present
as thin flat scales.

Second—The state of aggregation of these, and the rela-
tive amounts of each present in different soils, varies enor-
mously.

Third—The attraction of the soil particles for water varies
with their chemical nature; and particles of the same material
have a varying “affinity,” under different conditions (not now
well understood).

Fourth—Salts and organic matter, in solution, modify the
value of the surface tension of the liquid, the former generally
increasing, the latter decreasing it.

Fifth—The circulation of water is of two sorts, viz., (a) flow
due to hydrostatic pressure, or gravity, and (b) flow due to
capillarity.

Sixth—The permeability of the soil to water moving under
the influence of gravity depends largely on the size of the
tubes. The smaller the tubes, the slower the rate of flow.

Seventh—The penetration of the soil by water acting un-
der the influence of capillarity depends largely, also, but in a

*For general discussion see Whitney, op. cit.

tIn this connection Whitney states the interesting facts; that on
the ‘average about 50 per cent of the volume of soils is space occupied
only by air and water; that in a cubic foot of soil the grains have,
ou an average, at least 50,000 square feet of surface; and that soils
containing from ro to 30 per cent of clay consist, respectively, of from
four to twelve billion grains.

276 The American Geologist. November, 1898

reverse way, upon the size of the tube. The smaller the tubes,
for a given total area of cross section, the greater the amount
of water absorbed, and the higher it is elevated.

Eighth—For a given soil the retention of moisture when
loss from evaporation is suffered, depends upon the size of the
capillary tubes; the affinity of the soil particles for water; the
amount of water supply; and the length of the capillary tubes,
or the distance of the “water-table” below the surface.

Ninth—Its retention of moisture when suffering loss
through escape below depends, in great measure, upon the
size of the capillary tube,—the rate of flow through these for
a given amount of pressure varying as the fourth power of
the diameter.

Tenth—Soils, sub-soils, and the water reservoir, may all
differ in texture. The rate of flow of water to the surface de-
pends largely upon the nature of their texture and
the relative positions which they occupy. Further, the pene-
tration of the ground by meteoric waters depends largely upon
these same conditions.

Eleventh—Both the presence and the circulation of water
in soils depend upon very complex conditions, such as the
nature, size and shape of particles; their state of aggregation
or the texture of the mass; and the position and amount of
water supply.

Prof. Shaler* has called attention to the protection of beach
sands from abrasion by the presence of interstitial water held
between the particles by capillary attraction.

In another part of the same paper he records observations
in connection with sand dunes, where the capillary phenomena
appeared to be of a different sort. The observations were that,
after a rain-fall of an inch, the dune-sands ‘would often not
be wet for more than three-quarters of an inch beneath the sur-
face,” the water escaping to the lower hollows among the
dunes, without penetrating them; surface tension, if it be
the cause here, acting in a negative way to accelerate erosion
by preserving the sand in a dry state.

In view of the effects of surface tension under certain con-
ditions, this phenomenon may possibly be referable to it as

*In a paper presented at the meeting of the Geological Society,
December, 1893.

The Surface Tension of Water.—Ladad. 277

a cause. In a paper by Alfred M. Mayer,* on “The Floating
of Metals and Glass on Water and Other Liquids,” it is stated
as a result of experiments that materials which will ordinarily
attract water, may fail to do so when films of air are con-
densed on their surfaces, with the result that they will float
upon the liquid in question, even when loaded by weights
exceeding in value that of the “surface tension” of the
given liquid,

If, now, the grains of sand on the surface of the dune be
in the condition of the material described above, the attraction
between them and the water fails, at least temporarilv. to oper-
ate. The falling rain drops, larger than the interstices of the
sand, immediately coalesce into a sheet, which might remain,
through the operation of the tension on its lower surface, a
body of water of appreciable thickness supported on the col-
umns of sand penetrating it from below, but not in actual
contact with it. (See fig. IIT.)

Prof. Whitney says, in “Conditions in Soils of the Arid
Region,’ year book, U. S. Department of Agriculture, 18094,
e160:

“Water descends very slowly and to a very limited extent in a
perfectly dry soil * * * because the tension or contracting power
of the surface of the water is greater than the attraction of the soil
grains, which tends to cause its diffusion through the mass.”

This observation agrees with that made by Prof. Shaler
in the field, and with the result of Mr. Mayer’s laboratory ex-
periments. Nevertheless, in the experiments conducted by the
writer, c/ay dried to constant weight at 100° C. was used, with
the result that it absorbed water with extraordinary rapidity
and copiousness (in cases, as high as 200 per cent by weight,
as stated above). This would seem to indicate that some other
condition must be fulfilled than mere dryness, to render the
material non-absorptive of water. In fact, while making
chemical analyses of clays, and while determining hygroscopic
moisture, I have observed that the dry, clay powder would ac-
tually gain weight while in a chloride of lime desiccator, even
when left there for hours. It did not, however, so gain when
sulphuric acid replaced the chloride of lime.

*Science, N. S., Vol. IV, No. 88, Sept. 4, 1806.

278 The American Geologist. November, 1898

The theoretical possibility coincides with the phenomena
as actually observed. This case is the exact reversal, in the
position of material, of that of sand floating upon water, to
be discussed under another general heading. Here, the water
rests, as a sheet, upon a closely packed series of sand columns
(not attracting the liquid), and its thickness is limited by the
number of these, and by the strength of its surface tension.
The phenomenon ofthe sand dunes may bea capillary phenom-
enon, though the reverse of “capillary attraction; and the con-
ditions pertaining in the cases previously discussed, where
wetness and an ultimate coherent mass resulted, are also re-
versed. Surface tension, operating without adhesive attrac-
tion, tends to preserve the mass in an incoherent state.

Geologic and physiographic effects result from the com-
parative rapidity with which such sands are transported by the
winds. Prof. Shaler refers to this point and says: “In con-
sequence of this peculiarity of dune sands, which retards their
deep wetting in ordinary seasons, they are retained in march-
ime onder: 8.05". So that a strong wind may excavate and
bear away large quantities of the material.”

A study of sand dunes furnishes a valuable illustration of
what would happen to the fine clay and rock dust materials,
through wind erosion alone, if they were not consolidated by
the processes described.

The phenomena of drying and shrinking may in some spe-
cial cases, and in a limited way, counteract the general tend-
ency to retard erosion, thus seeming to accelerate it.

“Mud cracks” result, as shown, from shrinkage. The pro-
cess which forms them may, under certain conditions, accom-
plish in a local way this relative accelleration, and may effect,
in detail, minor physiographic changes.

I have seen very fine examples of this sort of work while
making canoe trips down some of our southern rivers, the most
beautiful cases being on the Chattahoochee. These occur on
both the Georgia and Alabama sides at many points below
Columbus, southward to the region of the swamps, near the
Florida line.

This interesting stream, within the limits mentioned, trav-
erses a series of strata, consisting largely of clays, marls and
sands. Fora distance, perhaps, of two hundred miles, it cuts

The Surface Tension of Water.—Lada. 279

through them so as to expose them beautifully in section, its
banks being often many feet high.

The singular physiographic feature produced by the force
under. discussion, is the occurrence of promontory-like pro-
jections beyond the vertical banks, over which minor streams,
in falls and cascades, tumble into the river.

Since flowing water naturally erodes such materials, as
marls and clays, ] was puzzled to account for the absence of
the recess usually found where one stream enters another.
It seemed remarkable that a considerable body of water could
be precipitated into the river, thereby increasing the destruc-
tive force, at the given point, and still produce the effect of
locally retarding erosion, that is, leaving little residuary prom-
ontories, while the clay walls retreated. But such the phe-
nomena were. The material of the promontory was that of the
bank in general, continuous with it, and in no way a deposit
by the stream; nor did it appear to be in any case hardened
by a local deposition of mineral matter. The explanation
sought seemed to be found, in a general way, in the fact that
the retreat of the banks was accomplished in part by some other
means than the under-cutting of the river, or erosion by rains:
and after careful observation a full detailed explanation seemed
to be as follows:

(1) Erosion’ by these lateral streams is at a minimum,
owing to the absence in them of transported material, due to
their flowing but short distances; and, in the main, across flat
surfaces rank with vegetation, which filters out the sediment.
(2) The clay material of the bank absorbs by capillary at-
traction the water precipitated on its surface by night as dew,
which falls very heavily in this region. This moisture is then
rapidly evaported by day, through the heat of a semi-tropical
sun, even though augmented by capillary waters from depths
below the surface. The result is a consolidation and shrink-
age on the face of the bank, which causes mud-cracks; and
since the extreme surface is the first to shrink, there tales
place a curling up of the edges of. the now isolated patches,
and a peeling off, in fragments, of a thin layer of the clay or
marl material. (3) Beneath the waters of the lateral stream
the clay is continuously in a wet state, and yet, though suffer-
ing from the under-cutting of the river and the erosion of the

280 The American Geologist. November, 1898

falling water, it retreats from the river’s edge more slowly than
the contiguous bank which is alternately wet and dry.

In short, these ‘‘promontories” result from the differential
retreat of the banks from the water’s edge,—the phenomenon
of surface tension leading to accelerated erosion where they
are not more or less continuously kept in the wet condition.
Of course, a number of conditions must be fulfilled to produce
such effects, as,—a suitable climate,—banks of just the right
materials and texture,—minor streams, such as drain local
swamps, for pure water;—and these conditions exceeding in
value the effect of the destructive work of the river in time
of flood.

The illustration, Plate VIII, is a view of one of these prom-'
ontories, taken by the writer from a canoe.* It should be
stated that the actual projection of the promontories into the
river, as here indicated, is but temporary,—during the period
of high water. The line of the bank beneath low water level
is continuous. i

In spite of my having said that the local erosion suffered
is at a minimum, owing to the purity of the water in the minor
streams, it must be confessed that they do experience con-
siderable loss from this source. They often have the shape of
talus cones, and frequently, owing to differences in the hard-
ness of strata composing them, a series of shelves is formed.
The water, falling successively over these, hollows small ba-
sins, and I have seen a series of such, carved from the rock,
closely resembling those built with deposits of sinter by hot
springs. Indeed, the fact that they are sometimes eroded
beyond that accomplished by ordinary causes and suffered in
common with the banks, but emphasizes the importance of
the special acceleration of destructional work resulting from
surface tension.

Other effects produced by capillarity are effloresent min-
erals, occasional ore deposits, some dendritic minerals, etc.

The most important of the efflorescent mineralsare the alkali
salts in some desert regions, and those brought to the sur-

*They are difficult to photograph, the river flowing very swiftly,
and cutting deeply and sharply against the bank, so that a landing
where they occur is usually impossible, and it is necessary to photo-
graph them in profile, in order to show their characteristics.

The Surface Tension of Water.—Ladd. 281

face on irrigated lands where the water supply is insufficient
to establish drainage beneath the surface.

The same process which produces shrinkage and consolida-
tion of clays, under certain conditions, results in the formation
of clay stalactites. J have seen, pendent from overhanging
banks of clay, stalactites which, though comparatively small,
resemble exactly in form, the stalactites produced by the pre-
cipitation of calcium carbonate on the evaporation of drip-
ping waters in caverns. The first of these seen were collected
with the idea that they consisted of some s2lt soluble in surface
waters. Examination, however, showed them to be composed
wholly of minute particles of quartzand scales of kaolinite. As
opportunity offered the manner of their formation was investi-
gated and found to be similar to that cf our ordinary stalac-
tites, except that the whole process is physical. Water, per-
colating through the clay mass above, carries with it some of
the finer material, and where points of equilibrium are estab-
lished between evaporation and supply these interesting forms
result, the occurrence of which I have never seen recorded.

Having once observed them, they have since come fre-
quently under my notice. At Rich Hill, near Knoxville, Ga.,
where a variety of Eocene beds overlie cross-bedded sands and
clays of the Lower Cretaceous, a section of two hundred feet
is exposed in an immense gully. Here, besides small pendent
stalactites, thin wavy ribbons of clay from two to three inches
broad are attached, edge-wise, to the sandy walls. Some of
them, three feet in length, resemble, in miniature, the “welt-
bertuhmten Vorhang”’ of the Adelsberg Grottoes.

Of the same nature as these occurrences are the thin coat-
ings of clay which wash down from overlying beds, and like a
coat of paint often conceal the character of the beds below.

Capillarity does not necessarily enter as a cause, but sur-
face tension operates to contract and to consolidate the parti-
cles suspended in the evaporating water.

The main facts, in connection with the action of surface
waters in a chemical way are too well known to need discus-
sion here.

Granting that the circulation of water in rock, soils and
clays, takes place as outlined above, it follows that the pro-
cesses which lead to the decompositions and alterations of the

282 The American Geologist. November, 1898

mineral units of our rocks, and which affect these latter so
considerably in the details of their composition and texture,
are also directly in part dependent upon this strain on the sur-
face of water.

Flocculation.

The phenomena of flocculation have been discussed by
various authors, largely in connection with the subsidence of
small particles in liquids. Among these are Hilgard, Brewer,
Barus, Whitney, Hunt, Skey, Rawley and Bliss.

The first three named considered the flocculation of such
particles and their behavior on the addition of certain solu-
tions as due mainly to chemical action, such as hydration and
dehydration. Prof. Whitney, however, and subsequent writ-
ers have urged a physical explanation, claiming that the fine
particles rendering water turbid are precipitated through floc-
culation, which results from the altered “potential” of the sur-
face particles of the water, due to the addition of certain salts
to the liquid.

If the particles in suspension attract the water more than
enough to overcome its surface tension, molecules of water
will tend to crowd toward the substance, and such particles
will be forced from each other and continue in suspension.
But if, on the other hand, these conditions are reversed, the
tendency to contract exposed surfaces will operate, wherever
possible, to wife particles, since this diminishes the amount of
such surface. This process increasing the weight of the ag-
gregations relatively much faster than the amount of surface
exposed, where friction tends to prevent subsidence, allows
them to settle, and leave the liquid clear.

In this manner we account for the sudden subsidence of
small particles suspended in rivers, where these enter the salt
waters of the sea, which are of still higher specific gravity;
and this process must be looked upon as of geological interest
if not importance.

Of more significance is the effect of such flocculation upon
the ‘¢exture of our soils, which is shown to be so largely mod-
ified by the presence or absence of substances in solution that
the production of crops, and the power of the soil to support
plant life, may be profoundly affected by the use of such so-
lutions, without reference to their fertilizing powers.

The Surface Tension of Water.—Ladd. 283

Attention has been called frequently to the function of clay
particles in producing the phenomena of flocculation result-
ing from their diminutive size, stress being laid upon the fact
that as bodies decrease in size the extent of surface rapidly
increases relatively to the mass.

There is a point, however, of equally great importance,
viz., that the shape of the particle can almost indefinitely ex-
tend the relative amount of surface. Thus, for a given
mass, angular particles expose more surface than spherical
ones. The surface of spherical bodies varies as the square of
the diameter, but if the particles be flat, the surface can be
increased relatively to mass, by change of shape (theoretically),
until the molecules of the substance all lie in a single plane.
As a matter of fact most minute mineral particles are general-
ly angular rather than rounded. Kaolinite, however, the es-
sential mineral of our clays, and so omnipresent, commonly
occurs in the form of thin cleavage plates. It is thus prob-
able that the diameters measured by Prof. Whitney for his
calculation on the amounts of surface exposed in different
soils were often the greatest diameters of flat particles, and
consequently the amounts of such surface would be even
greater than that indicated by him in his reports.

Floating of Matertals.

It is not uncommon to see materials of a higher specific
gravity than water floating upon its surface.

The principle involved is again that of surface tension,
and substances thus float only when attraction for the water
is less than the value of the latter’s surface tension.

The geological results of this principle are chiefly the float-
ing and shifting from place to place of sands. While I have
observed such an occurrence on many occasions, in different
places, the most important noticed was in Massachusetts, at

the mouth of the Merrimac river. Here the northern end of
~ Plum island, which is a vast accumulation of sand, shuts in
the harbor of Newburyport on the southeastern side. The
action of the winds, of the waves, in time of storm, and of
the shifting currents (the position of the harbor’s channel vary-
ing rapidly) result in the formation of numerous bays or
“basins” in the sandy island, on the protected side, often oc-

284 The American Geologist. November, 1898

cupying extensive areas. The largest of these, having a cir-
cumferance of something over a mile, has endured for the past
forty or fifty years. The sand consists mainly of coarse,
sharply angular quartz, but much feldspar is present, some
mica and numerous fragments of schistose and eneissic rocks.
Whenever, on the retreat of the tide, the beaches and the ex-
posed bars are dried by the sun’s heat, the returning water, if
not too greatly disturbed by unfavorable winds, lifts as it
creeps up the slope, the whole superficial film of sand, includ-
ing large thin pebbles of schist, and floats it gently away on
its surface. The surface of the water, near the shores bearing
the sand, commonly moves out toward the main river, even
when the tide is rising, the incoming water flowing beneath.

I have estimated that in the course of a year something
like a thousand tons of sand, at a minimum, are lifted and
borne away to new resting places by the floating power of sur-
face tension at this locality alone. This is, of course, however,
an insignificant factor in the general distribution of the sands,
as compared with the waves and currents, which sometimes
move acres of these materials to a depth of from twenty to
seventy-five feet in a few hours. The phenomenon of the nat-
ural floating of sand on water has been recorded by J. C.
Graham* and by F. W. Simonds.*

The surface tension of water together with the mutual
attraction which usually exists between its molecules and
those of clay and rock minerals, is a factor profoundly affect-
ing conditions on land surfaces. It accomplishes the shrink-
age and consolidation of clays and rock dust. It facilitates
the decomposition of rocks and retards the removal of the
products of decomposition to an enormous extent, although
in exceptional cases and under certain peculiar conditions it
acts locally to increase erosion. The existence of land veg-
etation is directly dependent upon it. It is responsible for
the occurrence of many efflorescent and dendritic minerals,
and some ore deposits, and it constructs, of clay, stalagmites,
stalactites and coatings on other rocks. It hastens the sub-
sidence of fine particles where streams and rivers enter the
ocean, and further causes the removal of coarse sand and

*Am. Jr otsei., IIL: Vol XUL3P. 476) Dea Tsoo:
+Am. Geol. Vol. 17, No. I, P. 29, Jan., 1896.

Copper and Lead in New Mextco.—Fflerrick. 285

thin flat pebbles on the surface of water in which they could
not be transported if immersed, a fact which may explain
the presence of scattered grains of coarse sand in beds of
fine clay.

The occurrence as seen by Mr. Graham was the removal
and floating away of sand by gentle waves, splashing against
the bars along the margin of the Connecticut river.

Prof. Simonds describes his observations on the Llano
river, in Texas, where dry sand was gently fed to the surface
of the water by an undermining process. He explains it
vaguely as a phenomenon of “superficial viscosity.”

THE OCCURRENCE OF COPPER AND LEAD IN
THE SAN ANDREAS AND CABALLO
MOUNTAINS.

By Pres. C. L. Herrick, Albuquerque, New Mexico.

A somewhat interesting occurrence of copper in the moun-
tain chain lying on the east side of the Rio Grande valley may
be most easily understood from the conditions in the San An-
dreas, which lies some ten miles east of Lava station south of
Socorro. The railroad here seems to pass through a syncline
as the exposures of Carboniferous near the river dip to the
east while the strata in the Andreas dip towards the north-
west. To one approaching them from the east, that is from
the plain of the white sands, the mountains present a rather
abrupt escarpment rising nearly directly from the plain. The
face is cut here and there by valleys and canons, but the con-
figuration and geologic structure are remarkably uniform. The
lower part of the scarp is composed of granite, gneiss or
quartzyte of the metamorphic series and in this respect the
conditions are precisely as in the Sandias and elsewhere in the
ranges bordering upon the Rio Grande. Above this granite
base rises the stratified series composed of Carboniferous
limestone and interbedded sandstones with a thickness of 600
to 700 feet. In lithological and paleontological character this
series presents no noteworthy peculiarities, but it differs from
the similar exposures further north in the fact that the entire
limestone series is cut by nearly vertical veins of considerable

286 The American Geologzst. November, 1898

size which run about at right angles to the strike. These veins
are numerous and occur at irregular intervals of a quarter to
half a mile or more, and are so conspicuous that a number
of them can be seen from the plain as depressed or elevated
bands crossing the strata. The thickness of the veins varies
also but many of them are from five to twenty feet thick and
are filled with the most diverse materials. Some are silicious
while others carry fluor spar, calcite, siderite, baryta, ete.
While the veins can be traced to the contact with the granite
they do not penetrate it, or if they do, it is only in the form of
a narrow fissure. It would appear that the flexure which pro-
duced these fractures had more effect on the stratified than
on the metamorphic rocks or that subsequent warping chiefly
affected the upper series. At the juncture of the Carbonifer-
ous limestone with the granite there is often a thin band of
red sandstone which has served to catch the leechings from
the entire series above. Thus it happens that there has ac-
cumulated a band of hematite at this contact which is some-
times quite pure by substitution, but, in the majority of cases,
is simply composed of a coating of the oxide covering the or-
iginal quartz grains so that, when broken, every individual
grain of the apparently oolitic ore is found to contain a quartz
nucleus. Mining men have been deluded by this appearance
into the attempt to use such material for iron flux; actually
adding a rock with about 80 per cent silica to an ore requiring
iron to assist in removing the excess of silica.

A very hasty glance at the situation is sufficient to ex-
plain the method of precipitation and segregation of the cop-
per ores. The latter consist of copper glance, malachite, cup-
rite, and, in fact, nearly all the common ores of copper mixed
with siderite and hematite and gangue matter. The sul-
phides of copper and associated silver must evidently have
come in from below, rising possibly, in the circulating water,
and it is equally plain that the iron band has accumulated
by leeching from the superposed strata. At the lines of inter-
section and in the presence of air the precipitation has taken
place. Comparatively little of the sulphides has collected be-
low the contact (iron) zone and very little has passed beyond
the iron zone to any great distance. It also appears that there
is a diminution of the deposit at a distance from the surface.

Copper and Lead in New Mexico.—FHerrick. 287

The showing at the intersection is often very good and has
been the cause of a great deal of profitless investment. It is
possible to point out the places where such deposits will be
found without: doing more than to stand at a distance and
note the points of intersection of the veins and the iron band
so that the geologist gets credit for a great real of acumen for
a prediction which is based wholly on a very simple metal-
lurgical principle. 3

The region described extends many miles along the eastern
slope of the San Andreas and similar conditions occur else-
where. It is true that a considerable amount of fine copper ore
occurs in these intersections and, with better means cf access,
they will no doubt be utilized, and it is elso true that there may
be found deeper workings where under different conditions
of accumulation large bodies of good ore might occur, but
the careful investor will avoid being deceived by the surface
showing and will beware of too general application of the
miner’s notion that mineral must “go down.”

The Caballo Mountains. Between the San Andreas and the
Rio Grande is a large stretch of desert plain called the Jor-
nada del Muerto which, from the lack of water, has long been
a terror to the freighters and packers. Much of pioneer ro-
mance has been woven into stories of the Jornada and even
since the railroad has bridged the gulf it is still unreclaimed.
Toward the western border of the plain there is a serie¢ of
basaltic cones from which there spread out over the plain
larger or smaller sheets of lava, the most northern of which,
at San Marcial, extends to the river. At this place the lava
flows over a deposit of sand and stratified loam not unlike
that west of Albuquerque. This series of basaltic flows is a
continuation of that further north in the valley but the river
at this point has been diverted to the west. The occasion for
this diversion is apparently the elevation of a minor axis on the
western border of the Jornada forming the San Cristobal and
the Caballo mountains, in Sierra county.

Both these ranges rise quite abruptly from the eastern edge
of the river valley to a variable hight. The Caballo range
is the higher and is that with which we at present have to do
and is mentioned in this connection to illustrate the modifi-
cation of the same method of precipitation as that seen in the

288 The American Geologist. November, 1898

San Andreas mountains. The western escarpment is for the
most part very steep with evidence of very considerable meta-
morphism. The very axis of break in some places is preserved
and affords very interesting illustrations of what can be done
in the way of altering a limestone by the agency of mechanical
friction and pressure without the presence of a source of igne-
ous heat. So far as seen, there is no intrusive in this range
but the displacement along the axis of uplift was very great
and the area affected was quite narrow. The sequence of the
strata seems to have been about the same as elsewhere in the
valley although opportunity was lacking to make a sufficient
examination of the lower as well as some of the higher strata
at points where the absence of excessive metamorphism would
admit of expecting organic remains. The fossils seen from
the upper part are such as are found in the upper three hun-
dred feet of the Carboniferous in Bernalillo Co., the abundance
of Bryozoa being quite characteristic. Below the middle there
are shaly beds in which are found the same facies which occurs
in the lower parts of the series as exposed in Socorro and
3ernalillo counties but the lower one hundred feet is so al-
tered in all the places visited that it is impossible to deny the
local belief that it contains some strata of an age’ earlier
than the Carboniferous. However, it may be said that there
is no evidence of unconformity in the series where undis-
turbed and there is nothing in the lithological character of this
portion to dispose one to regard it as other than the sandy
lower part of the Carboniferous as seen elsewhere in the valley.
Such fossils as Chonetes mesoloba, Spirifer opima, Martinia
lineata, Aviculopecten carboniferus, Terebratula sp? Pro-
ductus cora, P. nebrascensis, in the lowest fossiliferous beds
examined and certainly below the middle of the series permit
us to expect that the lower parts will prove Carboniferous.
The foot of the western slope is granite, gneiss or schis-
tose rock of a somewhat nondescript character, varying from
place to place and much mingled locally along the axis, which,
while in general trending north and south, has many local off-
sets and irregularities. Above the granite is a band of quartz-
yte as usual, the thickness being little more than twenty
feet. At the contact with the limestone series is a coarser
phase which from its position immediately above the impervi-

Copper and Lead in New Mexico.—Herrick. 289

ous stratum formed by the granite, becomes the collector of
the iron leeched from the rocks above, forming a band of var-
iable width in which the sand grains are coated with iron ox-
ide or replaced by it. In this case the collection is not so
complete at this horizon as in the San Andreas by reason of
the fact that the metamorphism of the sandy lower layers of
the limestone has been so complete as to form water-bearing
horizons above, and there has been a good deal of accumul2-
tion of iron in the same way at these higher levels. Along the
axis of uplift the effect on the silicious materials has been very
great, and there has been a thickening of these bands. The
lime, on the other hand, has been abruptly turned on edge
and the selvedge has been wedged in between the less altered
lime and the granite till from a distance it appears in sections
as though there had been an igneous intrusive thrust up at
this point. Such an appearance is very deceptive in the sec-
tion in the Palomas Gap canon and affords a most interesting
geological object lesson. The general conditions are repro-
duced in the accompanying diagram.

Caballo Mt
Cupriferous
Nea

Ww i ops &
j ys eh Wyle hs
Sy Yi; ae Sa be GS Oetipe
iy Wy, ie ti Kgs Cys ry LEGS

Ge Yi Lis i

aes

LA
LI Y,

SS : ce Be ACRES fs ace os: >
Carboniferous Beez Fe SRE Carboniferous ae Zrins Pe eeesis

The whole series is subject to the same system of frac-
ture lines so much in evidence in the San Andreas and the
collection of copper at the intersection of the veins with the
iron band is similar, with this difference that, inasmuch as
the iron is also to some extent precipitated in the lower mem-
bers of the limestone series, the sulphides are also more ex-
tended in the vertical direction. This fact will also probably
militate against the collection of very large bodies even at the
intersection. The chemistry of the copper precipitation may
well be a subject for speculation. That the iron is leeched
from above can hardly be doubted and it is equally probable
that the copper came up in some form from the depths along
the fissures. It is obvious too that no considerable part of

290 The American Geologist. November, 1898

the copper has been precipitated in the granites or in part of
the lime not within reach of the iron. It may be that the ac-
tion of the air-bearing water near the surface tended to liberate
sulphurous oxide and that an iron solution thus formed in
the vicinity of the ore of iron produced the necessary condi-
tions for precipitation, very much as they are supplied in cer-
tain leeching plants for the treatment of copper.

On the east side of the mountain near the axis, the lime
is much tilted and is also disturbed in the direction of the
strike of the range. In fact, the disturbances are of the most
profound nature, yet the dip in general is sharply to the east
and the limestone is minutely veiny. These veins are filled
with fluorite, barite, quartz, and calcite and may also carry
certain, or rather very uncertain, quantities of galena and, in
some instances, wulfenite.. One or more faults parallel to the
range repeat the strata toward the top of the formation in the
successive foot-hills to the east and in these the metamor-
phism has been less intense and the veins are not quite so nu-
merous. The larger ones cross the strata in, or nearly in,
the plane of the dip and are sometimes quite large and in such
cases often carry large quantities of galena in a barite gangue.
In general. however, the veins give off “feathers” extending
for fifty to seventy-five feet and these collateral veins are quite
as likely to carry lead as the main vein so that the total amount
of ore is difficult to recover. The commercial concentration
of ores rich in heavy spar at a distance from water and fuel
becomes an economic problem of as much difficulty as
interest.

The time may doubtless come when nature will accom-
plish the concentration of the lead in much the same manner
that it has done it in the Magdalena mountains and elsewhere
where the sulphide, after having been altered to the sulphate
is precipitated as a carbonate. That this process is in progress
is shown by the fact that in the more exposed parts of the
workings upon the veins the galena is quite extensively re-
moved, and in parts not removed it is partly changed to sul-
phate. To determine in advance the secret chambers where
the percolating waters will find the conditions for the repre-
cipitation of lead is beyond our power and this legacy to the
future must be left to the future to recover.

Giants’ Kettles near Christiania and in Lucerne.—Upham. 291

Following the Carboniferous limestones is a series of very
red sandstones and shales which is not shown in conformable
relations to the lime but is seen in the ridges to the east of
the latter lying with a much less sharp dip to the east. It may
be that these beds, three or four hundred feet thick, are sup-
ported by Carboniferous strata but the contact is not exposed.
No fossils except the trunks of trees have been found but from
the lithological character, position and from general analogy
they may be supposed to represent the so-called Juratriassic
of other parts of the territory.

Following these red beds are the grey sand-stones and
dark shales of the Cretaceous. It is impossible to determine
the thickness of this formation but it is undobtedly extensive
and, after forming the numerous ridges east of the red beds,
the strata become less inclined and extend indefinitely to the
east and are in places capped by the lava beds. Two rather
small beds of coal are found in the lower part of the Creta-
cous as here exposed. The paleontological evidence is fairly
complete but has not been sufficiently examined. Beds of
Ostreas occur in the shales not far from the coal and in these
the shells are well preserved.

{European and American Glacial Geology Compared, X.]
GIANTS’ KETTLES NEAR CHRISTIANIA AND
IN LUCERNE.

By WARREN UPHAM, St. Paul, Minn.

The glacial rivers recorded by eskers belonged to the time
of departure of the ice-sheet. Any very long esker was not
deposited wholly at once; or, in other words, contemporane-
ous origin cannot be affirmed for different parts of its extent.
Its formation took place in the peripheral, stream-channelled
margin of the ice; and it grew in length, up to 100 miles or
more in some instances in southern Sweden, as also-in Maine,
being deposited progressively from south to north, as the con-
tinental glacier retreated. The steepness and frequently
crooked courses of the eskers prove that they were not over-
ridden by the ice-sheet to which they owed their origin, nor
by any later glacial readvance. Probably their material was

292 Lhe American Geologist. November, 1898

washed away from superglacial drift, exposed by ablation,
mostly within ten to twenty miles back from the edge of the
ice, and at altitudes ranging from 50 or 100 feet to 1,000 feet
above the land. To such altitudes we may believe that drift
was borne upward into the basal part of an ice-sheet a mile
thick, if we may draw a proportional estimate from the Malas-
pina glacier of Alaska, and from the observations by
Chamberlin, Drygalski, and others, concerning the plenti-
ful englacial drift in the lower part of the terminal cliffs of the
Greenland icefields. Moreover, in the esker of Bird’s Hill,
near Winnipeg, Manitoba, I have found conclusive proofs that
much englacial drift, becoming at last superglacial, existed
there at hights exceeding 500 feet.

Another evidence of glacial rivers is supplied by water-
worn pot-holes, called in German and in the Scandinavian lan-
guages ‘“giants’ kettles,” which were bored in the bedrock be-
neath glaciers or an ice-sheet by torrents of water falling
through deep moulins. This name, moulin, coming from the
French and meaning a mill, is applied to a vertical tunnel,
melted at first by the waters of the surfzce trickling into some
very narrow crevasse that has just begun to open, until, after
enlargement by this dissolving action, it receives sometimes
a large stream, such as could not be waded, pouring with e
thunderous roar down a cylindric shaft to the rock floor under
the ice. The esker rivers belonged to the closing stage of the
Glacial period; but the torrents eroding glacial pot-holes in
Scandinavia, Switzerland, and the United States, appear, as
will presently be explained, to have attended the accumulation
of the ice-sheets. The streams that bored these pot-holes or
giants’ kettles were very small, and were only very scantily
drift-laden, in comparison with the rivers which formed the
ereat esker ridges.

In the close vicinity of Christiania, Norway, numerous
eiants’ kettles have been discovered and cleared of the glacial
drift and water-rounded stones which filled them. The locality
of greatest interest is Kongshavn, a southeastern suburb on
the shore of the Christiania fjord, where, between the lines of
low and high tide, a glacial pot-hole eroded in gneiss was
found, on the removal of its drift contents, to be 16 feet deep,
with a diameter of 5 feet. Another pot-hole, from which the

Giants’ Kettles near Christiania and in Lucerne.—Upham. 293

drift was excavated under Prof. Kjerulf’s direction, measures
34 feet in depth on one side and 44 feet on its higher side, hav-
ing a nearly cylindric but somewhat spiral or rifle-like form, 8
to 12 feet in diameter. The altitude of its mouth is go feet
above the sea.*

Taking up the question of the probable epoch or stage of
the Ice age in which the Christiania giants’ kettles were eroded,
we are confronted by the occurrence of marine shorelines and
shells in deposits overlying the glacial drift, which demon-
strate that during the time of the glacial recession there the
land was depressed about 600 feet below its present hight. It
is impossible to ascribe the moulins and pot-holes to torren-
‘tial agency beneath the sea level, and consequently they must
belong at Christiania to the earlier time of high land elevation
and snow and ice accumulation.

Our Scandinavian travels ended in the journey along the
Denmark peninsula as described in the sixth paper of this
series; and thence we passed, in a very busy week, through
_ Hamburg, Berlin, Dresden, Prague, Linz, and Salzburg, to a
Sunday’s rest, August 8th, 1897, in Bischofshofen, a most
quaint alpine village, which was our railway junction for the
next day’s journey through ‘Tyrol, by Innsbruck, to Zurich.
On Tuesday morning we took the earliest train to Lucerne;
and, after a few hours spent in a visit to the Glacier Garden,
sped onward, by railway and steamer, over the Brunig pass,
into the upper Aare valley, to Meiringen, Brienz, Interlaken,
and Grindelwald. The next day was occupied in excursions to
the lower and upper Grindelwald glaciers,+ and in climb-

*“Giants’ Kettles at Christiania,’ by W. C. Brogger and H. H.
Reusch, in Quart. Jour. Geol. Soc., London, XXX (1874), 750-771.
{NOTES ON THE GRINDELWALD GLaciERS.—The lower glacier has re-
treated about a third of a mile, and the upper glacier about a sixth of
a mile, during the last thirty or forty years, as is known by the scanti-
ness of vegetation and the absence of bushes and trees on the some-
what semicircular areas so lately laid bare. The drift of these areas
is largely waterworn, but much typical till or ground moraine is visi-
‘ble closely adjacent to the present end of the upper glacier.

We went about 200 feet into the upper glacier in a passage cut for
visitors, and at its end observed the granulation of the ice, a candle
being kept burning behind a detached block to display this structure.
The granules are of varying size up to 1% inches long, fitting together
with sharply defined and angular boundaries, as figured by Deeley and
Fletcher (Am. Geologist, vol. X VII, pp. 16-29, Jan., 1806, with a plate
which shows sections of glacier ice, its figures 2, 4 and 5, being from
this glacier).

2094 The American Geologist. . November, 1898

ing high up on the grassy mountain opposite these glaciers
for its glorious view of the snowclad Bernese Oberland
mountain range, culminating in the Finsteraarhorn and the
Jungfrau. Thus far our few days in the Alps had been favored
with the most beautiful weather; but Thursday brought rain,
in which we went onward to Bern, visiting its very interesting
historical and archeological museum, cathedral, clock tower.
and bears’ den, thence continuing in the clearer afternoon to
Lausanne, with its magnificent prospect across the lake of
Geneva. On Friday we regretfully left Switzerland, and
passed through the Jura ranges and by Dijon to Paris. In-
stead of less than a week, I would again spend a month or
two, or a year, amid this grand Tyrolese and Swiss country,
the playground, resting-place, and sanitarium of Europe.

Excavation in the glacial drift for a cellar, in the year 1872,
first revealed a part of the very admirable group of giants’
kettles which is now one of the chief attractions of sight-seers
in Lucerne. This town itself is in many respects the most
fascinating one for tourists in Switzerland, and the most
convenient for many neighboring excursions, as to Mts. Rigi
and Pilatus, and the sail on the wildly picturesque and historic
Lake of the Four Forest Cantons. The Glacier Garden is
about 100 feet above the lake, and is only a few steps from the
Lion Monument designed by Thorvaldsen, which was chiselled
from the solid rock fifty years earlier (in 1821). Thirty-two
pot-holes of moulin torrent erosion are inclosed in the Garden,
occurring irregularly grouped upon a remarkably furrowed,
waterworn, and glacially striated rock area about eight rods
long and four rods wide, which was originally so drift-covered
that its wonderful torrential and glacial sculpture was con-
cealed. The covering of soil and drift has been removed since
1872, and many rounded stones, which served as grinders
rapidly whirled around by the falling waters, from those of
small size up to others of huge dimension, five feet or more
in diameter, have been removed with the gravel, sand, and
clay that filled these rock kettles.

A very interesting rock cafion, which was subglacially eroded by
the large stream flowing from the lower glacier, is now exposed by its
retreat along a crooked course of about 1,000 feet. The cafion is
mainly about 150 feet deep, and varies from 15 to 100 feet in width,
except that it is in part narrowed and closed above, along a distance of
about 200 feet, by movement of the rock walls, originally separate but
now in contact.

Giants’ Kettles near Christiania and in Lucerne.—Upham. 295

The largest pot-hole of Lucerne, on the northwest border
of the group, has a diameter of 26 feet and depth of 31 feet.
Its southern side overhangs, probably because the northwardly
flowing current of the overlying glacier carried the moulin
slightly forward while the rock erosion was taking place. The
movement was least at the base of the glacier, and increased
differentially upward. The moulin therefore became inclined,
and discharged its torrent somewhat backwardly into the rock
kettle, hollowing it thus with an overhanging wall. The same
feature is observable in several others of these pot-holes, and
many of them display spiral wearing. In some instances the
pot-holes have irregular and composite forms, showing ap-
parently that successive and independent moulins, probably
of different years, contributed to their erosion. They range
in size from the largest to others 9 or 10 feet deep and 4 or
5 feet in diameter, and to small cylindric or hemispherical
kettles only one or two feet deep.

It is also to be noted that the rock at two or three places
is waterworn in broad and somewhat crooked grooves, vary-
ing in depth to six or seven feet, and extending 20 or 30 feet
in length, where the moulin torrent was less concentrated and
more variable than usual; or, more probably, these grooves
may have been made by a very inclined and powerful englacial
and subglacial stream there impinging on the rock floor. Per-
pendicular pot-holes of the usual form, but of small size, occur
occasionally in the grooves. It is especially noteworthy, both
here and in other localities of Europe and America, that gen-
erally the edge or lip of the giants’ kettles, whether large or
small, is abruptly cut in the rock surface, perhaps sometimes
because of their partial removal by glaciation subsequent to
the moulin erosion. They seldom have a flaringly curved
mouth, such as more frequently characterizes pot-holes seen
at the present time in the process of erosion by cascades in
brooks and rivers.

Rock exposures adjoining giants’ kettles are often un-
marked by other waterwearing; but in every present stream
having falls and eroding pot-holes, larger spaces are irregularly
worn and channelled. The rock kettles of moulin formation,
found where no stream now exists nor can be supposed to
have ever flowed except when the country was ice-enveloped,

290 Lhe American Geologist. November, 1898

are the predominant or the only form of water erosion in their
vicinity; but at the falls of ordinary streams, pot-holes are ex-
ceptional, or a subordinate feature, among more extensive
grooving and other fantastically waterworn sculpture. It
is evident, too, that glacial planation, ensuing after the moulin
origin of the giants’ kettles, although probably in many places
effective to intensify this contrast, cannot generally be its chief
explanation, which is rather to be found in the protection af-
forded by the ice covering the rock contiguous to the base
of the moulin. The rebounding water, indeed, welling up
from one side of the rock kettle, may perhaps have usually
flowed away, for its immediate exit, in an englacial tunnel, or
at least with some drift between it and the rock. The condi-
tions of erosion of the giants’ kettles prevented or minimized
contiguous waterwearing, which, on the other hand, is favored
and predominant wherever pot-holes are made by subaérial
streams.

In Vermont and New Hampshire pot-holes have been ob-
served by Profs. Edward and Charles H. Hitchcock, and by
the present writer, in localities where they must be referred
to the Glacial period. Sometimes, on hills and mountains and
on lake shores, they were undoubtedly due to moulins; but in
several instances they occur at cols over which the outlets
of ice-dammed lakes appear to have passed.* On the sea-
shore in Cohasset, Massachusetts, subglacial pot-holes have
been described and figured by Mr. T. T. Bouvé;+ and nu-
merous others of similar origin are known in that state, but
await publication. Indeed, they are of frequent occurrence,
but mostly remain undescribed, throughout the entire glaci-
ated region of the United States and Canada. ;

The most remarkable known of these giants’ kettles, wheth-
er we consider their size or the manner of their occurrence
and discovery, are two found in 1884 and 1885 in Lackawanna
county, Pennsylvania, about three miles northwest of Arch-
bald. As described by Mr. C. A. Ashburner, the Archbald
pot-holes are 1,000 feet apart and were both discovered in

*Geology of Vermont, 1861, pp. 216, 930; Geol. of N. H., vol. III,
1878, pp. 64-66, 249.

+“Indian Pot Holes, or Giants’ Kettles of Foreign Writers,” Proc.
Boston Soc. Nat. Hist., X XIV, 1880, pp. 219-226; with discussion by
Warren Upham, pp. 226-228.

Giants’ Kettles near Christiania and in Lucerne.—Upham. 297

coal mining, their bottoms being in the coal bed. When
the drift filling the one first discovered was cleared out, it
was found to be 38 feet deep, with a diameter of about 15 feet
at the bottom, increasing to a maximum of 42 feet and a min-
imum of 24 feet across its top. The second pot-hole, of sim-
ilar basal diameter in the coal bed, had not been cleared of
its drift contents; but it is known from the levelling and test-
pits or borings of the mining company, to have a depth of
about 50 feet in the rock, with a covering of 15 feet of drift
above.*

According to these observations and records of glacial
pot-holes, in their best known localities of both Europe and
America, it seems to me most probable that the time of
their excavation in nearly all cases was the early part of the
Glacial period, or some stage of glaci-l extension, when the
ice-sheet was being formed upon the land by snowfall. On
any hilly country the ice must have attained an average depth
somewhat exceeding the altitude of the hills above the ad-
joining lowlands before any general motion of the ice-sheet
could begin. During the process of slow accumulation of
the ice-sheet, the summer melting upon its névé surface would
produce multitudes of rills, rivulets, and brooks, which might
unite into a large stream, and this, pouring through a cre-
vasse and melting out a cylindric moulin, might fall perhaps
100 or 200 feet or more on a moderately hilly region, but
probably sometimes 500 feet or more on 2 mountainous dis-
trict, while yet the ice motion, though sufficient to permit the
formation of the crevasse, might not have gained a definite
current to carry the crevasse, moulin, and waterfall away from
the spot where they were first formed. We may thus explain
the continuation of a glacial waterfall in one place while it was
excavating one of these giants’ kettles. After the ice-sheet
acquired a current because of the greater thickness and pres-
sure of its mass, such deep cylindric excavations in the bed-
rock could not be made; and during the recession and final
dissolution of the ice-sheet it seems probable that its receding
border had steeper gradients and consequently even more

*Geol. Survey of Pa., Annual Report for 1885, pp. 615-625, with a
map, sections, and two plates (views from photographs of the first pot-
hole when cleared out for use as an air shaft.)

298 The American Geologist. November, 1898

rapid motion than during the culmination of the Glacial peri-
od. Moreover, the streams formed on the surface of the ice-
sheet by the summer melting before it was so thick as to have
motion would be free from drift, so that they could readily
find their way through crevasses, wearing pot-holes in the
rock beneath, and thence flowing in subglacial courses; but,
on the contrary, the superglacial streams during the departure
of the ice, which then became more or less covered with the
previously englacial drift, laid bare by ablation, were heavily
freighted with the gravel, sand, and clay of the modified drift,
which must have soon choked up the passages wherever these
drift-laden streams found crevasses, causing them to flow in
superficial channels walled and underlain by ice, until, near
their mouths, the ice was melted through to the ground and
kames and eskers there received the coarser parts of the riy-
ers’ burden.

The rate of erosion of the giants’ kettles, referred to a
stage of incipient glaciation, and the rate of formation of
kame knolls and hills and esker ridges during the wane of
an ice-sheet, were surprisingly rapid, in comparison with the
generally very slow rates of geologic action. Watch the
artificial processes of granite and marble abrasion and _ pol-
ishing, and there will be no need to doubt that the largest
rock kettle of Christiania, Lucerne, or Archbald, could be
hollowed out during the warm months of even a single year
by a stream 20 or 50 feet wide and 2, 3, or 5 feet deep, fall-
ing down a moulin 200 or 500 feet deep, and well supplied
at the bottom with grinding boulders of granite and other
very hard rocks. Crevasses and moulins would be formed
in successive years at nearly the same situation, thus pro-
ducing such a profusely kettled surface as in the Glacier
Garden.

Much later, if the retreat of the icefields under ablation
was so rapid as a tenth of a mile yearly, apparently its rate
near Stockholm according to observations noted in the pre-
ceding paper of this series, or about half a mile each year
during centuries, as was probably true of the area of the
glacial lake Agassiz and the vast plains of the Saskatchewan
and Winnipeg country, we cannot doubt that the most mas-
sive eskers, as in Sweden, and the highest kame hills, as the

Origin of the Archean Igneous Rocks —Winchell. 299

Devil’s Heart hill, 175 feet high, in North Dakota, could be
formed within a few years for any single section, or perhaps
even within one summer for the great kame mentioned.
Some of these gravel-depositing rivers, as shown by the
widths of esker ridges and plateaus, were two to five or ten
times larger than those of the moulins and rock kettles.

THE ORIGIN OF THE ARCHEAN IGNEOUS ROCKS.
By N. H. WrNncHELL, Minneapolis, Minn.

It has been shown by the writer in a previous paper* that
the greenstones of the Archean are the oldest known rock,
and may safely be considered, in our present state of knowl-
edge, as the existing representative of the original crust of the
globe. This, of course, leads to the necessity of admitting
that the primordial magma was a ferro-magnesian one, at least
so far as it existed at the surface of the cooling globe, and it
would be also reasonable to admit that igneous rocks of later
date, having the same composition, were derived from the
same magma from deeper points within the earth. With this
for a point of departure, it becomes necessary to inquire into
the origin of the alkaline magma which gave rise to the gran-
ites and igneous gneisses.

It was likewise shown in a previous paper that the granitic
magma made its appearance amongst the rocks of the earth
at a later date than the ferro-magnesian, since the oldest alka-
line rocks occasionally intrude into the oldest ferro-magne-
sian.

These two types of Archean igneous rock may be accepted
as the dominant great facts in Archean vulcanology, and all
subordinate facts may be considered as attendant and acci-
dental, but yet legitimate, consequences of the reign of these
two. This statement necessarily covers the occurrence of
igneous rocks of intermediate characters. They must be con-
sidered as in some way dependent on the leading role played
by the greater agents, and as unimportant in a fundamental
inquiry into the origin and mutual relations of those greater
agents.

*Am. Geol. Oct., 1898, p. 262.

300 The American Geologist. November, 1898

It is a curious and interesting fact that, while numerous
geologists, and especially T. Sterry Hunt and Michel Lévy,
reached the conclusion, on chemical and speculative grounds,
that the first crust of the earth was a ferro-magnesian rock,
only in recent times has it been possible to refer directly to
that old crust as at present existing and susceptible of exam-
ination. On all hands it has been assumed that the oldest
known rock was an acid one, represented, in Caneda, by the
fundamental or Ottawa gneiss, which, being an alkaline-acid
rock, has been supposed not only to represent the earliest
magma, but the starting point in a period of magmetic differ-
entiation. It is necessary, on the other hand, if the green-
stones express the character of the earliest magma, to reverse
the process of differentiation, and to seek some way of produc-
ing the alkaline-acid magma from the ferro-magnesian.

These extremes of differentiation, or at least of difference,
present remarkable contrasts when considered from a chem-
ical point of view, the most noticeable of which is the occur-
rence in one of certain elements which do not exist in the
other, or exist in but small amounts. The “crenitic hypothe-
sis’ of Hunt was intended to explain how all the crystalline
rocks, both acid and ferro-magnesian, could be derived from
the earliest magma, by a long-continued process of lixiviation
by circulating waters. Such waters were supposed to have
brought the elements of the early magma to the surface of
the earth and to have deposited them under circumstances
favorable for their consolidation into all the varied rocks of
which the Archean consists. Hunt entered into an extended
survey of the secondary minerals of rocks, and an investiga-
tion of their methods and sources of generation. He found
that in a manner satisfactory to himself, all the minerals of
the alkaline magma can be explained as derivatives from the
ferro-magnesian magma, at least in small amounts. By this
extended lixiviation Hunt believed that the original crust of
the earth was wholly destroyed, or at least was deeply buried
under its own ruins, and could not be anywhere identified.
The greenstones, which, as stated, are the base of the series,
he put into the “Huronian,” and their production he consid-
ered the last step in the process.

Recalling, now, the principal chemical characteristic of the

Origin of the Archean Igneous Rocks.—Winchell. 301

alkaline magma, it is seen at once to consist in the presence of
potassium, which is wanting in the normal ferro-magnesian
magma. Another characteristic is the prevalence of free
quartz. Let it be supposed that the crenitic operation began
to act on a doleryte, which Hunt supposes was probably the
original rock, it may be asked, how could there be leeched
out of doleryte a large amount of potash? It may also be
asked how, while the potash was being extracted, and also the
necessary amounts of lime, sodium and of aluminum, there
could be obtained from the same rock an excess of silica
which would give rise to a large amount of free quartz in
the resulting product. If it be said that under exceptional
conditions such a result might be produced locally, it is not
sufficient, for exceptional and local conditions are not those
demanded by the hypothesis. The extraction of the char-
acteristic elements of the acid-alkaline magma from the ferro-
magnesian is to be considered the usual and normal operation,
for there is no reason in assigning the origin of one of the
greatest rock masses of the globe to the operation of abnormal
and exceptional conditions. It may be confidently asserted
that no potash could be obtained from a rock or from a
magma in which none existed, and therefore that the chief
characteristic of the alkaline magma must have had some ex-
traneous origin.

It is not to be inferred from this that Hunt overlooked the
necessity of accounting for the origin of the alkaline silicates.
It is necessary, therefore, to look a little more closely into his
facts and his inferences from them. This, however, may be
confined to his discussion of the secondary origin of orthoclase
in connection with the diabase rocks of the Keweenawan, as in
this mineral are contained all the elements of the investiga-
tion. It is plain that if orthoclase is found as a secondary
mineral, as a result of change in a diabase, even in small
amount, it is presumptive evidence of the extraction of potash
from the associated diabase.

It is true that, prior to Hunt’s announcement of the cre-
nitic hypothesis, it had been shown by J. D. Whitney that
orthoclase occurs in veins and sometimes in vesicular cavi-
ties in the trap rocks of the Keweenawan,* and this had also

*Am, Jour. Sci., (2), XXVIII, 16, 1850.

302 The American Geologist. November, 1898

been confirmed by Pumpelly in a masterly research into the
metasomatic generation of various minerals of the copper-
bearing rocks.* Hunt makes much of this fact, and expands
it into such scope that he deduces the general law that, the
alkaline silicates are naturally one of the products of the cre-
nitic process, and inferentially that the orthoclase of the veins
and amygdaloids is a product of alteration of the diabase
which contains them. This, however, is wholly a gratuitous
and even impossible inference, not only because of the difficul-
ties already referred to, but because of the attendant state-
ments of Pumpelly. It will be seen, by an examination of the
tabular grouping of the secondary minerals of the copper-
bearing rocks presented by Pumpelly, that these minerals ap-
peared in a certain order, as they are often super-posed in
geodes and veins upon each other, and that orthoclase appears
near the end of the series. In this table there are thirteen
steps of mineral genesis, metallic copper being number six
in the series and orthoclase number twelve. It seems, there-
fore, that not only did the zeolitic minerals all precede the
formation of orthoclase, but also that metallic copper was
earlier than orthoclase. The significance of the occurrence
of orthoclase in cavities in the diabase, so far as that fact beers
on the source of its elements, is less than that of the occur-
rence of copper, but if, for the sake of the argument, it be
considered equal to that of the occurrence of copper, we are
confronted, on the argument of Hunt, not only with the deri-
vation of potassium from diabase, but also with the generation
of metallic copper in large amounts from the same rock,
neither of which elements exist in diabase in its normal and
pure state.

We are, however, relieved of this difficulty by a different
explanation. The origin of metallic copper in the Keweena-
wan rocks is now generally attributed to the circulation of
mineral waters carrying the salts of copper in solution at a
date considerably later than the origin of the diabase, such wa-
ters having parted with their copper occ2sionally in cavities
in the diabase, but most abundantly in the cavities in the
interbedded conglomerates +

* Am, Jour, Set, Vol. Il, Sep, ‘Oct. Nov.,(1871) )Proc, Am, Acad.
Arts & Sci., XIII, p. 253, 1878!

tPumpelly, Am. Jour. Sci., Vol. II., 3rd Ser., p. 352, 1871.

Origin of the Archean Igneous Rocks.—Winchell. 303

Such waters having an extraneous source their mineral
character must also have had a foreign origin. They could
not at least have been derived from the diabase, since the chief
deposits are not in the diabase rock, but in a coarse conglom-
erate—and if from the diabase, on this evidence, then in much
greater quantity from the acid conglomerate.

Therefore, if mineral solution from a foreign source de-
posited metallic copper at the sixth stage of the process, how
much more likely that orthoclase, at the twelfth stage, was also
generated by mineral solutions from an extraneous source,
neither of these substances being indigenous in diabase.

It may still be claimed that all, or at least many, chem-
ical analyses of diabase show the presence of a small amount
of potassium which may have been sufficient at least to
generate the orthoclase seen in the veins and geodes. Sup-
pose that be admitted, it still demonstrates nothing. Such
potassium found in diabase, or even in a soda-lime feldspar,
is always accompanied by a certain percentage of water, as
testified by chemical analyses, and the presence of water points
to a certain amount of decay and the introduction of foreign
ingredients. Theoretically there is no hygroscopic water, and
no potassium in any of the minerals of a pure diabase. If
water, potassium and metallic copper be found, on analysis, to
exist in a certain diabase, they may all be considered equally
as of later introduction from a foreign source, and they, there-
fore, could have had no agency in the supposed widespread
transformation of the ferro-magnesian magma to an alkaline
one. .

Hence the principal evidence of Hunt for the leeching of
potash by any sort of “fermentation,” such as assumed by the
crenitic hypothesis, and the generation of orthoclase, and
hence of all the alkaline silicates, from a ferro-magnesian mag-
ma, seems to be inadmissible. If the principal step in support
of the crenitic hypothesis is found to be unwarranted, all the
subordinate and secondary steps in that process are rendered
insecure and purposeless.

This difficulty also stands obviously against all other hypo-
thetical processes of derivation of the alkaline-acid magma
from the ferro-magnesian, whether by differentiation at the
surface or in deep reservoirs, and the idea of such origin of

304 The American Geologist. November, 1898

the granite magma has to be abandoned, at least if any hy-
pothesis more reasonable can be substituted.

The only other existing hypothesis for the origin of gran-
ite and the associated igneous rocks is that which refers them
to the fusion of deeply buried sedimentary materials. This
hypothesis, which at first glance seems to have a facies of rea-
son and probability, is essentially that which was proposed by
Hutton as contrasted with the oceanic view of Werner. With
some modifications in the methods of application and opera-
tion this view has survived till the present. It was repeated
by Keferstein (Naturgeschichte, des Erdkorpers, vol. I, p. 109,
1834); also Bull. Soc. Geol. France (1), vol. VII, p. 197); by
Herschell (Proc. Geol. .Soc. London, II, 548, 1836); Hunt
(Geol. Magazine, June, 1869; Chem. Geol. Essays, 1874, p.
59), afterwards abandoned for the crenitic hypothesis); Le
Conte (Am. Jour. Sci., Nov: and Dec.,’1872); King (Ges
Geol. Ex. goth Parrallel, vol. I, p. 705 et seq., 1878); Dutton
(Geology of the High Plateaus of Utah, pp. 123 et seq., 1880);
and the writer in 1888 (Am. Assoc. Adv. Sci. XX XVII, 212,
1888).

There are still more recent discussions of the manner and
the physical conditions under which sedimentary rocks be-
come plastic and flow as a molten magma, or crystallize in situ.
Messrs. Crosby and Fuller (Mass. Inst. Tech. Quart., IX, 326-
356, 1896; Am. Geol. XIX, 148, 1897) in discussing the origin
of pegmatyte reach the conclusion that it is an intermediate
representative between rocks deposited by solution and those
that result from cooling, from fusion, that onone hand pegma-
tyte is inseperable from veins, which are of aqueous origin,
and on the other grades into true granite which constitutes
true dikes and bosses of igneous origin. They argue, there-
fore, for the intimate co-operation of heat and water not only
in the formation of pegmatyte but of all granites. Through
pegmatyte, therefore, there is a crystallline connection, open
to observation, between the fragmental end of rock genesis
and the igneous. The significance of this connection, in its
bearing on the origin of granite, is not fully entered upon
by Crosby and Fuller.

About the same date Prof. C. R. Van Hise has, in a mas-
terful manner, gone into the principles of pressure, strain and

Ongin of the Archean Igneous Rocks. —Winchell. 305

plasticity which must apply to the deeply buried sediments
(Sixteenth Annual Report of the U. S. Geological Survey,
1897), and shows that by the co-operation of aqueous and ig-
neous agencies, simultaneously under great pressure, all rocks
would be compelled to act in some measure the same as
molten masses. Notwithstanding these suggestive links of
connection between the igneous rocks and the clastics which
they penetrate, Van Hise does not propose, any more than
Crosby and Fuller, that there is any genetic bond between the
clastics and the granites.

Although on several occasions there have been published
in the reports of the Minnesota survey certain evidences of
the transition of clastic rocks into crystalline rocks, such zs
gneiss, and granite-gneiss and finally into granite, there has
not been until lately any careful investigation of the rocks
themselves in their transitional petrographic characters.

But one locality has been studied in this manner. The
field observations need not be rehearsed, for the megascopic
facts are published in detail in the reports of the survey.
This locality is that about Kekequabic lake. Here is a granite
that shows both the clastic and igneous characters, as exam-
ined in the field. It is crystalline, massive and intrusive on
the adjoining sediments, but grades off into fragmental rock,
the gradation into fragmental rock being especially evident
when the clastic rock was conglomeratic, the boulder forms
of the coarse clastic still remaining.

Without going any more fully into the field evidence, it will
be interesting, perhaps, to note the petrographic transition.
This area of granite is small, a circumstance that brings the
whole series involved between the granite and the fragmentals
within narrow limits and warrants greater confidence in draw-
ing the important conclusion. It rises in the form of a small
dome in the middle of the Lower Keewatin. The clastic strata
adjacent consist of siliceous actinolitic schist, in general
terms, but they vary in different ways. The hornblende ele-
ment becomes coarser, and the rock assumes the character
of a peculiar porphyry. At other times the hornblende is
partly replaced by augite which is allied to egyrine, and in
nearly all cases it can be seen to have been derived from
augite by a uralitic alteration. This derivation is evinced chief-

¥

300 The American Geologist. November, 1898

ly by the parti-colored polarization which sometimes repre-
sents exactly the original crystal form of the idiomorphic
augite, surrounded by fringes of external growth beyond the
augite limits. When the augite grains were fragmentary, or
were corroded before being enclosed in this rock, the horn-
blendic growths have exactly filled them out, the dark color
of the polarization (or even the color seen in ordinary light)
showing distinctly the original augite outlines. Besides the
conspicuous hornblendes sometimes this schist contains traces
of feldspars, but usually feldspar is not evident except when
the whole rock becomes coarser. When feldspar is seen dis-
tinctly in the schist, the crystals often appear to have been
altered into a micro-granulitic mass of secondary grains which
appear to be of quartz and feldspar. Sometimes pellet-like
spots appear, under the microscope, which are occupied by
such granulation. By their assuming distinctly lighter and
darker aspects four times in one revolution, there appears to
be a remnant of the original feldspar grain with its orientation
still intact. The “ground mass,” so to speak, surrounding
these altered crystals, is composed largely of finer condition
of the same elements, but usually it embraces also a notable
amount of quartz, which is in the form either of free grains
of angular clastic shapes or of fine and intimately interlocked
chemical deposition. With the fine-grained quartz is appar-
ently also equally fine feldspar.

This green schist is sometimes composed almost wholly of
actinolite spicules. At other. places it passes into a greenish
geraywacke. It is distinctly a fragmental rock, and shows
a coarse, even pebbly structure, the pebbles being usually of
rock like itself, but finer-grained. It is considered to be large-
ly of the nature of an old volcanic tuff, grading, as it does, into
the greenstones of the Keewatin.

In the first place it should be noted that there is a strik-
ing mineralogical affinity between the schist-conglomerate and
the crystalline rock, in that they both contain augite, and that
this augite is of the nature of egyrine; also that the feldspars
of the schist-conglomerate, having very striking and unusual
characters, are duplicated in the granites—i. e., the original
feldspars are remarkably twinned and zoned. ‘This statement
as to the augite is not demonstrated, but rests on the concur-

Origin of the Archean Igneous Rocks —Winchell. 307

rent evidence of other microscopic character. It is evident
that in such a schist it would be almost impossible to -find
augite retaining its crystalline form, for it readily changes to
hornblende, that being indeed almost the first mineralogic
change that takes place in a volcanic tuff of such age. But
the augite cores remain in the schist, sometimes, as augite,
and, ona still broader scale, the original forms of the augites
are outlined in the resultant hornblendes by difference of ab-
sorption and of colors between crossed nicols. Exactly the
same characters are seen in the augites of the porphyry and
granite-porphyry, where the preservetion is sufficiently perfect
to disclose the zgyrine characters of the original augite. As
to the sameness of the feldspars, with their peculiarities, there
is no question.

These two important characters ally these rocks in some
way in a genetic bond, for the feldspars especially are wholly
unlike any known elsewhere in the state. Chemical analysis
points to anorthoclase, but the zoned structure, when analyzed
by the microscope, indicates that the feldspars began as lab-
radorite, passed to andesine, and, sometimes at least, termi-
nated as albite, there being a continual increase in the acidity
of the magma in which they were generated.

The general aspect of the granite (seen in thin section)
along the south side of Kekequabic lake is suggestive, not of
crystallization from a magma, but of simple induration of
coarse debris. The feldspar grains do not interlock, except as
they have been enlarged by a secondary growth, and in many
sections examined they do not even come into contact, but
are separated, very generally, by a space which is occupied by
a fine interlocked secondary development of feldspar and
quartz. The margins of the feldspars frequently are inter-
locked in this new growth. As ‘this fine matrix increases in
amount, so the rock becomes porphyritic; as it increases in
coarseness, so the rock becomes granitic, but in all cases, or
in nearly all, there is a distinct difference between the old
feldspars and the new. Along with this generation of new
feldspathic material, is also the recrystallization of the quartz,
thus making a truly granitic rock. The old feldspars, which
in the schists proper, without metamorphosis have a tendency
to disappear by a process of micro-granulitization into a fine

308 The American Geologist. November, 1898

mesh of secondary feldspar and quartz resembling the sur-
rounding matrix, are by metamorphism regenerated by new
borders, and by micro-granitic growths of coarser grain, and
by these new growths interlock about their margins. Occa-
sionally the old feldspars embrace and surround idiomorphic
small crystals of augite, having taken that relation in the
magma in which they were generated, but the later feldspars
do not enclose augite in that way. When the fragmental
augites are not altered to hornblende, which alteration is usual,
they are simply embraced between the newly developed feld-
spars. The old feldspars, thus contrasted with the new, can
be distinguished with more or less certainty in nearly every
section examined.

Again, in the midst of the sedimentary schist are found
coarser, hardened beds that present as compact and crystalline
a texture as some of the intrusive granite. Such recrystal-
lized beds are associated conformably with others that are
not so hardened, the regular sedimentary relation and struc-
ture being continuous through them all. This hardening and
recrystallization of the schist evidently is irregular in distri-
bution. Throughout the schist, even in its least metamorphic
conditions, there is a fine background of micro-granulitic
quartz, or quartz and feldspar, which is ready, in case of the
application of new forces, to take on new forms. The back-
ground matrix, in the porphyry as in the granite, is the same,
fine interlocked quartz, or quartz and feldspar. In the por-
phyry it seems to be a micro-granulitized feldspathic debris,
for numerous feldspars can be seen, partially changed to
such a micro-granulitized condition.

It is, however, with the conglomeratic condition of the
sedimentaries that the most evident transitions occur to the
eranite. These are conspicuous in the field, and with the mi-
croscope the finer elements are seen to be simply compacted
together with but slight interstitial material. The crystals
all being, as supposed, of the nature of volcanic ejecta ar-
ranged somewhat by water, the elements of the rock embrace
these with small amounts of erosion products, the latter in-
creasing with distance from the supposed volcanic source.
One of the most evident and instructive instances of granitized
conglomerate is that seen along the south shore of the lake

Origin of the Archean Igneous Rocks —Winchell. 309

in sec. 31, T. 65-6. The fragmental character is most evident,
and many of the pebbles are rounded. There is no short
transition, but the whole rock over a certain belt acquires the
granitic texture by the secondary development of interlocking
minerals. The original, clastic, feldspars were mainly in frag-
ments, but some were nearly complete as crystals. They are
cemented together by fresh feldspars and by quartz. As
grains they never interlock with one another.

The facts, taken ensemble, seem to warrant the conclusion
that the same rock is both clastic and intrusive, and therefore
that as an intrusive it is derived from the clastic beds in situ,
and had no deep seated source. ‘This is not an isolated case
of the observed recrystallization and intrusive action of clastic
strata. In the Adirondacks, according to numerous observ-
ers, the limestones have been made to intrude the adjoining
quartzytes and gneisses, and to surround isolated portions of
them much in the same manner as igneous rocks. This fact
led Emmons and some of the early geologists to class crystal-
line limestone amongst the igneous rocks.

If this source of the granitic rocks be admitted in the case
of the Kekequabic lake granite, it is hkely to have been
equally efficient in other localities, and, indeed, it rises to
the importance of a general cause applicable, in the absence of
other sufficient source, to all the granites of the state.

It remains only to call attention to one of the conse-
quences of this hypothesis, should it be accepted. It is nec-
essary to find in the clastics which accumulated between the
epoch of the basal greenstones and the intrusion of the gran-
ites, the excess of silica and the potash which characterize
the alkaline magma. That the schists and sedimentary
gneisses contain a large amount of free silica, and also much
orthoclase and microcline, is a fact which only needs to be
mentioned to be admitted by every petrographer. In case
those rocks suffer refusion it is inevitable that the rock pro-
duced would contain the same elements.

We know of no way, other than erosion and volcanic ac-
tion, and the chemical precipitations provoked by such action,
by which the sedimentary products of-the Archean could have
accumulated. As erosion of the ferro-magnesian rocks that
seem to have constituted the first crust could not, as already

310 The American Geologist. November, 1898

shown, have given rise to these chemical peculiarities, they
must have come from the waters themselves, and primarily
from the sky, either as volcanic tuffs or as precipitations from
the surrounding atmosphere. It is reasonable to presume
that the early volcanic products would be like the early crust,
ferro-magnesian, and not alkaline. We are to look for these
elements, then, rather to the atmosphere in its normal condi-
tion—i. e., in its condition normal to the Archean age, just fol-
lowing the congealing of the first crust. The question is then
one that is chemical and physical, and is resolved into an
inquiry whether the world’s great stock of potassium was
stored up in the Archean because of the operation of the
Laplacean hypothesis in its progressive unfolding. It is a
question which leads into an examination of the volatile point
of potassium and into its chemical properties and its probable
activities under Archean conditions, and as such it is beyond
the scope of this paper.

GLACIAL THEORIES—COSMICAL AND
TERRESTRIAL.

By E. W. CLAyYPoue, Pasadena, Cal.

The enigma of the Ice age is still unread. When the gen-
eral scepticism which greeted the promulgation of the doc-
trine had given place to acceptance the cause of so portentous
an interruption of geological evolution became a topic for in-
vestigation of the first importance. And it has proved to be
a topic of extreme difficulty. While it is now impossible to
deny the occurrence of glacial conditions, probably several
times repeated during the recent history of the earth, yet it
has thus far been impossible to discover any sufficient or satis-
factory cause for so great and widespread a lowering of the
temperature over much of the temperate zones—a lowering
that was sufficient to bring Arctic conditions almost down to
the latitude of 35° in North America, and to 45° in Europe,
to cover the mountainous regions of the globe everywhere
with thick sheets of snow and ice and to extend the antarctic
cold to limits only a little less wide than those over which the
northern glacial winter prevailed.

Glacial Theories—Cosmical and T. errvestvial—Claypole. 311

The early speculation of Lyell in the later editions of his
classic works were marked by the caution so characteristic of
the man. Attempting to find in changed relations of the land
and water a sufficient cause for extensive changes in
‘the temperature, and at the same time lacking the
necessary data in soundings and in geological observa-
tions outside of Europe he could do little more than
theorize. And as the progress of discovery showed
that little solid basis exists at present or had existed in time
geologically recent for many of his speculative changes, the
terrestrial theory, as it may be called, gr-dually lost ground.
It seemed impossible by means of admissible recent geograph-
ical movements to find any sufficient cause for so vast a re-
frigeration as that which the observed phenomena of the Ice
age appeared to require. Geologists begen to look elsewhere
and to seek in extraterrestrial of cosmical conditions a solu-
tion of the mystery. Variation of the sun’s heat from age to
age was assigned as a possible means of accounting for con- -
temporaneous variation of the temperature of the earth. But
no proof or even probability of any such change could be pro-
duced. The variability of variable stars is in all likelihood
due to totally different causes. Inequality in the temperature
of the regions of space through which our system is careering
is another altogether gratuitous assumption on which a glacial
theory has been founded. But it is as baseless and as con-
trary to probability as the former. Moreover, as it has been
more than once pointed out, either of these two theories
would have cut off the glaciers at their source by reducing
the evaporation and consequently the rainfall.

The only cosmical theory that has been rendered sufficient-
ly plausible to command acceptance is that which was put for-
ward more than a quarter of a century ago in the pages of the
“London, Edinburg and Dublin Philosophical Magazine” by
Dr. James Croll. This, which was in effect terrestrial, though
based on astronomical facts was supported by its author with
such ability and ingenuity that it obtained for a time very gen-
eral approval in the geological world. It not only assigned a
possible and seemingly a probable cause for the oncoming of
the Ice age, but requiredits recurrence at least several times
during the past, and its repetition on a smaller scale during

212 The American Geologist. November, 1898

each recurrence. Moreover, it offered so tempting a means
of linking together geological and astronomical times that it
awakened a hope that the two might ere long by its agency
be united. The fundamental fact also—the secular elongation
of the major axis of the earth’s orbit—was so firmly estab-
lished that it admitted no dispute, and the secondary principles
deduced from it were invested by the skill and eloquence of
the author with such a halo of efficiency and probability that
no one need feel any surprise at the rapid advance of the
theory in the geological world.

But with the progress of research there have “cropped
out” certain difficulties and objections which were but slight-
ly, if at all, conspicuous at the outset. Among these is the
condition demanded by Dr. Croll’s theory that the arctic and
antarctic eras of glaciation were not contemporaneous but
alternate. With this it stands or falls. But geologists can
find no evidence for the alternation. On the contrary all the
facts bearing on the question, though few, fail to show any
difference in date. The ice-marks, whether scratches,
grooves, or boulders, are equally fresh in both hemispheres, so
that it is impossible to believe in a difference of 20,000 years
in their age as required by the theory. Then the work done
on the surface since the ice passed away is too little to fill the
long interval of 80,000 years which Dr. Croll assigns to the
past glacial era. The gorges of Niagara and of St. Anthony
are too small to have supplied occupation for their streams
during so long a time. Many other similar facts point very
strongly in the same direction, so that geologists generally
are more disposed to bring the close of the cold era and the
disappearance of the ice within ten or fifteen thousand years
than to admit the 80,000 years of the Croll hypothesis. Again,
the apparent irregularity and want of contemporaneity shown
by the glacial phenomena in various places indicate a less
general cause than one whose action extended at once over a
half of the globe.

These and other considerations have during the past few
years gradually undermined the hypothesis of the brilliant
Scotch geologist, so that it may now be said to stand much
less securely than it did twenty years ago. In spite of its ac-
counting for the recurrence of glacial and interglacial condi-

Glacial Theories—Cosmical and T. evrestrial.—Claypole. 313

tions as no other has ever done, there is yet a consciousness
that its base is slipping away and that the superstructure is
unstable.

As a result attention has been again directed to strictly
terrestrial conditions, and the newest results of investigation
have been employed in order to find, if possible, sufficient
cause for so intense a period of refrigeration in latitudes so
low. The contour lines of the Atlantic have been quoted to
prove that ancient continental shores exist at two levels, which
have been named respectively the ‘Continental’ and the
“Blake” plateaux. To bring both these above the sea-level
at present would need an elevation of ten or twelve thousand
feet to the south and much less to the north. So great a
change of level, if real, must have been attended with momen-
tous results, both in the drainage and the temperature, and
the investigation of these details is the most recent line of re-
search in glacial geology. Beyond all question it is quite pos-
sible to picture a state of things much resembling the Ice age
with the data thus supplied. The diversion of the gulf stream
or its reduction in temperature would certainly chill the north
Atlantic and the British Isles and might even so far reduce
the temperature as to cause a precipitation in the winter which
the summer might be unable to melt, thus producing an ac-
tual Ice age. Add the refrigeration due to the postulated ele-
vation of the temperate coast of the north Atlantic to that due
to diversion of the warm current, and the two may well be
allowed to have produced more momentous climatic changes,
perhaps even all the phenomena of the Ice age in western
Europe and eastern North America.

The importance of this contribution to the literature of
the subject can scarcely be over-estimated. It suggests a
possible cause for at least a part of this mysterious episode in
the history of our earth. But it is very far from complete-
ness and equally far from meeting all the conditions of the
problem. We may fully admit that vast elevations and de-
pressions of parts of the surface have taken place without
being compelled to admit the elevation of the West Indies to
the extent of 12,000 feet. But to deny its possibility would be
equally illogical. There are numerous side-issues needing
consideration and many minor problems awaiting solution be-

214 The American Geologist. November, 1898

fore the elevation in question of the “Continental” and the
“Blake” plateaux can be accepted as the cause of the Ice age.
Some of them may be worth stating.

Ist. An elevation of 12,000 feet over any large area is
known only in Thibet, where the great Desert of Gobi or
Shamo constitutes the wildest, windiest and snowiest region
outside of the arctic circle.

2d. Assuming as a fair rate of elevation three feet in a
century we should require 400,000 years for the uplifting of
the “Blake’’ plateaux above the Atlantic level, so that the
time since the Ice age reached its maximum would on this
theory exceed even the long limit assigned by Croll.

3d. In order to allow the occurrence of interglacial
periods we must assume not a continuous but an intermit-
tent elevation with alternations of subsidence, allowing amel-
ioration of the climate. Moreover, if the elevation was the
main cause of the refrigeration these subsidences must have
ensued to an extent sufficient to cause this amelioration. We
shall therefore be compelled to postulate in this case not one,
but several oscillations, almost or altogether to the full extent
given above, a result which will multiply the length of the
glacial period several times and render the discord still great-
er than in the case of the theory of Croll.

4th. It will be necessary to find similar conditions in
other regions in order to explain their glaciation. Not the
basin of the north Atlantic alone but almost every other part
of the temperate zones and even the mountainous regions
within the tropics have been witnesses of a great extension of
their present glacial systems. It is not easy to require eleva-
tion over all these places at once or even consecutively. Nor
is it any easier to conceive how the results of elevation else-
where could extend over districts so remote. The diversion
of the gulf stream by the Antillean uplift might chill the north
Atlantic but could scarcely affect the Kiwu Siwu of the
Pacific or change the climate of Patagonia or of New Zealand.
If the crust of the earth has been so uplifted and depressed in
all these regions as to cause the Ice age the Pliocene and Pleis-
tocene eras must have been a time of instability exceeding
what now comes within geological experience.*

*Note: See for further. details on this subject a paper by the
writer on “Eccentricity versus the Facts’ in the Trans. of the Edin-
burgh Geological Society for 1891, and also “Glacial Notes from the
Planet Mars” in the American Geologist for 1895. Vol. 16, p. 91.

Conglomerates in the Galena Series.—Sardeson. 315

It would not be just to infer that in consequence of these
objections the “elevation-theory,”’ as it may be called, is not
a valuable contribution to glacial literature. On the contrary
every possible solution of even a part of the greatest problem
in Pleistocene geology is welcome. Even if it prove incapable
of solving the whole it may yet be an important aid to the at-
tainment of the desired results. Probably the publication of
Dr. Croll’s hypothesis even if it should prove, as now seems
likely, entirely incompetent, has done more to stimulate the
progress of glacial geology than any other single event of this
century.

It is scarcely necessary to add that any theory of the Ice
age must be capable of explaining all the many and intricate
facts connected with it and must, of course, be in accord with
the actual course of recent geological history. At the same
time the full investigation of all the physico-geological ramifi-
cations of any fundamental first cause of the Ice age must be
a task of excessive intricacy and length. Consequences may
come to light apparently quite unrelated to it which are yet
its necessary though distant results, and it is not improbable
that this strange chapter in the history of the earth may at
last be found to be an outcome of more than one principal
cause whose interaction has brought about the remarkable
consequence—a singular point in a curve—an intersection of
two mathematical lines—a physical result exalted by acci-
dental coincidence with another.

INTRAFORMATIONAL CONGLOMERATES IN THE
GALENA SERIES.

By F. W. SARpESON, University of Minnesota.
(Plate IX.)

The continuation of the Trenton and Hudson River
groups, as they are most often designated, from New York
state westward through and beyond the Ohio river basin, is
well known to geologists and a description here of their extent

316 The American Geologist. November, 1898

is doubtless unnecessary. This paper has to do with the equiv-
alent or continuation of the Trenton group in the upper Miss-
issippi basin, especially at St. Paul, Minnesota. To explain
briefly: the Chazy formation, the Trenton including the Black
River formation and the Hudson formation including the Uti-
ca of New York are, as is generally recognized, represented
in this area by three divisions, the St. Peter sandstone, the Gal-
ena series and the Maquoketa series respectively. It is still
somewhat indeterminate whether the Trenton stage compris-
ing the formations or divisions just mentioned, has all its sub-
divisions represented in the upper Mississippi basin. The
Trenton stage is very thick in the New York region while the
equivalent here is thin, not exceeding 400 feet. Yet a com-
plete sequence of beds would appear to be developed in both re-
gions and the much thinner western representative is probably
not to be considered as an incomplete one, but rather each sub-
division there may have its coordinate here. This hypothesis
accords further with the great. uniformity and wide extent of
each bed of this stage in the Northwest. In a former article,*
I have endeavored to show how the several parts of the Galena
and the Maquoketa series are nearly coextensive over their
known extent, but I was not able to describe an exact relation
between the Trenton stage of New York and that of the
Northwest, because the necessary store of evidence for such
an undertaking is not at hand. <A few data only were con-
tributed on the deposits here. Ruedemann, + Whitet and Pros-
ser and Cumings§ have materially increased our knowledge
of the New York Trenton stage deposits in recent articles.
Ruedemann describes especially evidences of oceanic cur-
- rents in the Utica formation and again similar evidence from
conglomerates in the Trenton formation. Although it may
be very little known to geologists, yet conglomeratic zones
exist in the Galena (Trenton) series in Minnesota and Wiscon-
sin, and evidence of marine erosion or corrosion recurs in it
at several horizons. These zones, moreover, appear to mark
the divisions between successive faunal and stratigraphic beds,

*American Geologist, vol. 18, p. 357; vol. 10, p. 21.
tAmerican Geologist, vol. 21, p. 75; vol. 19, p. 367.
tf Dranst INS YeeAcad Sci volmnse ips

SFifteenth Ann. Rep. N. Y. State Geologist, p. 619.

Conglomerates in the Galena Series.—Sardeson. 317

and may be found in fresh strata both in the limestones and the
shales or clays. Possibly the newly discovered conglomerates
in the New York area may be genetically correlative with
some of those in the Northwest.

At Saint Paul and Minneapolis, Minnesota, quarries have
been opened revealing unweathered strata in the Galena series,
and in these may be observed the exact demarcations between
beds and strata. There are the first six beds of the series in
place here (see plate) and a large part of the Saint Peter sand-
stone exposed below them. The tops of the several beds
carry either a conglomerate or again a corroded surface mere-
ly, while the bases of the same bear no similar structure. A
contrast may be drawn therefore between these and basal con-
glomerates; these being evidently due to corrosion mainly,
are of small mass and lie at the top of the stratigraphic subdi-
visions, within the formation, while the others are due to
erosion and form a large mass lying at the formation’s base.

Beginning with the oldest Galena stage stratum, i. e., from
the top of the Saint Peter sandstone there is found at Minne-
apolis, and similarly at Saint Paul, an abrupt transition from
the pure sand to a mixed sand and clay deposit two to three
feet thick upon which is a stratum of clay and calcium car-
bonate containing a few fossil imprints. This stratum is two
feet or less thick. The next stratum, which is less than two
feet thick, may be designated a limestone. It is compact, but’
contains numerous smooth, black-surfaced, irregular pebbles
which contrast strongly with the blue or buff color of this and
other strata. A few inches from the top of the stratum is a
black seam or surface and the rock is discolored to a slight
depth. The surface is somewhat polished although it is not
uniformly plane. Above it the rest of the stratum, four to six
inches thick, is irregularly shaly and bears patches of numer-
ous small black pebbles and coarse quartz grains, associated
with or in large fucoidal casts, which may have been alge. |
interpret the characters of these strata as indicating that the top
of the Saint Peter sandstone was disturbed and its sand mixed
with clay deposited at the time which the first succeeding
stratum represents. The next stratum indicates quiet un-
disturbed sedimentation. The next one, which contains the
black seam or smooth surfaced lamina, shows that a con-

318 The American Geologist. November, 1898

siderably thicker deposit first accumulated, but was largely
reabsorbed during an interval of non-deposition. The re-
absorption left the surface irregular and the top of the stra-
tum saturated with oxide of iron and manganese. Extreme
irregularities of the surface may have given origin to loose
isolated blackened pebbles, or the same may be parts of a
broken up stratum or lamina, reduced by absorption like the
ground surface. The existence of these pebbles through the
stratum above and beneath the black seam indicates that
more than once such periods as the blackened surface repre-
sents, had obtained, but that the result of their existence, the
black surfaceshad been later broken up. The association of
fucoids with the pebbles may indicate that the latter were
sometimes transported by the former, which their proportion-
ate size would seemingly also indicate.

The above described strata lie at the base of the Buff lime-
stone bed at the bottom of the series, (see plate [X). This bed
is about thirteen feet thick excluding the transition strata just
described. The top of the Buff limstone bed has also a black
stained irregular semi-polished surface, upon which the first
laminze of the succeeding bed, the Bellerophon bed, rest in a
sort of non-conformity on a small scale. The limestone strata
part along this plane and its existence is often obscured by
weathering, but again in many places one can observe well
how the upper limestone penetrates the small irregularities and
borings in the blackened surface of the lower one. Again the
Bellerophon bed has the upper surface of its top stratum irreg-
ularly sculptured and blackened. Here there is often a dis-
continuous lamina with its surface also blackened and bored,
resting upon the main surface. The first succeeding stratum,
belonging to the Stictoporella bed, is usually limestone but a
shaly carbonaceous thin layer here and there intervenes.

Black pebbles, such as are abundant near the first, or low-
est corrosion zone are not observed with the second and third.
But the fourth one which is in the top of the Stictoporella bed
(plate IX) has on the contrary pebbles, and not a continu-
ous blackened surface associated, at that place. In the top-
most laminze of this bed, among numerous fossils, are flat
irregularly moulded pebbles about one inch in width and
smaller. The Stictoporella bed is mainly composed of clay

Tur AMERICAN GEOLOGIST, Vou. XXII. PLATE IX.

Orthisina
conglomerats
ted
TOK
Corrascom yone
oolte
conglomerate
Fucoid Se
bed
con glomira te
“1 ookcte
conglomerate
sliclopora
Led
50
— 40" < = ——s| conglemerate
Stictopor
ella bed
— 30 — — 2 Corrosion
pone
Bellerophon
bed
Corroston
jene
Bull
limestone
corrosion
Zone

Transition
St.Peter stn.

Section of the Galena series showing corrosion zones and conglomerates.

Conglomerates in the Galena Series.—Sardeson. 319

shale in.its upper portion and in this the pebbles are embedded,
or again they are in the shaly surface lamina of a limestone
stratum. It seems remarkable that the pebbles lie in the top
of the Stictoporella bed and not in the basal! portion of the
succeeding one. Their position is like that of the pebbles
and the blackened irregular surfaces at the top of lower lying
beds.

The fourth of the series of beds has also its conglomerate
in the highest layers. The bed is 30 or more feet thick. It is
composed of clay with more or less discontinuous layers of
limestone one to three or four inches thick. At Saint Paul
this bed has been excavated recently in such a manner as to
permit the unweathered undisturbed strata to be closely
studied. About ten feet below the top there is a thick lamina
of oolitic limonite. The same is not preserved in the weath-
ered clay and for that reason probably it has never before
been observed. Pebbles a foot wide and three or four inches
thick and smaller ones occur two feet below the oolyte lamina
and again near the top of the bed. These strange occurrences
have been found distributed or partly heaped together in a
manner to show that they form a conglomerate. Thev are
parts of broken up limestone strata and both their composi-
tion and content of fossils show them to have been broken
from the bed in which they now lie. The pebbles are irregu-
larly lenticular, smooth or bored full of holes, blackened and
partly encrusted by Bryozoa, monticuliporoid corals, crinoid
roots, etc. They rest sometimes obliquely upon one another
like shingle. They are mostly large pieces, several inches
wide and are embedded in fine, fossil-bearing clay or in fos-
siliferous limestone strata which are not unlike that from
which the conglomerate pebbles must seemingly have been
derived. To.explain this intraformational conglomerate it
seems not necessary to assume that the pebbles as such are
the result of erosion, but rather that the exposed top of the
bed being a limestone stratum, which was not covered by
other deposit, it was attacked by the sea water and reduced to
lenticular pieces. Their blackened, bored and encrusted sur-
faces show that they lay a long time upon the sea bottom.
But they are alike on both sides, and again they seem to repre-
sent more than one stratum and it may therefore be necessary

320 Lhe American Geologist. November, 1895

to further assume that water currents were strong enough to
disturb them at least by moving the clay from around them,
and to bury them again. The limestone stratum from which
they came had consolidated before they were formed. The
sedimentation was interrupted in the same manner two or
more times during the deposition of the upper third of the
bed.

Following the Stictopora bed comes the twenty foot thick
Fucoid bed, which is the fifth in the series. The bed is a clay
with calcareous laminz and fucoids interspersed and a few
firm limestone strata intervening. At or near the top there
is again oolitic limonite to be found and close below it a few
cake shaped pebbles two to six inches wide. The top stratum
is an impure but brittle limestone. Its upper surface when ex-
posed shows a blackened planed field, with numerous abrupt
pits and borings characteristic, one might say, of a sea bottom.
But it is not encrusted by Bryozoa or other fossils. The strat-
um itself bears no well preserved fossils and seemingly none
of any kind except fucoids, but these nearly compose all the
upper strata, and are abundant throughout this bed. Suc-
ceeding strata are very fossiliferous and minute shells and
zoaria are often beautifully preserved in large numbers. They
belong to the Orthisina bed. About nine feet above the
Fucoid bed the strata contains pebbles similar to those in the
Stictopora bed, although smaller and more dispersed. They
lie in the lower half of the Orthisina bed, but at the top of a
division which I here formerly designated as the Zygospira
bed.

It is evident to one examining the Galena series’ strata that
the six beds exposed at Saint Paul and Minneapolis are separ-
ated by intervals of non-deposition of sediments. The beds
are characterized by faunal differences and the interruptions
in the life sequence now appear to coincide with interruptions
in deposition of sediment. Of course the deposition of sedi-
ment may have ceased innumerable times during the building
of the several beds and not infrequently etched shells and
zoaria bear evidence that they lay long unburied on the sea’s
bottom, but intervals sufficiently long to permit marine erosion
and corrosion to form blackened unconformable surfaces and
black manganese stained pebbles, mark the upper parts of the

Conglomerates in the Galena Sertes.—Sardeson. AIK

beds as described. The seeming exception in the lower part
of the first bed or Buff limestone may rather be in accord with
the rule and the strata between the corrosion zone and the
Saint Peter sandstone should accordingly be designated a
distinct bed. Heretofore this part has been called the “trans-
ition” although the paucity of fossils and its rare exposures
have left us in doubt whether or not it is a distinct faunal
zone. Recent investigation of it has resulted in the finding of
several species all but one of which occur in the overlying bed;
the one species however is quite strange and has not yet been
identified. It is an Ophileta. In the Stictopora bed the last
twelve feet of the 30 or 35 feet bear first a conglomerate, then
an oolyte zone and possibly other lesser conglomerate zones
besides the chief one at its top. This part of the Stictopora
bed seems the most irregular in thickness of any part of the
series, although one can not be certain of that because its
position in the middle of the shales causes it to be seldom
well exposed. An attempt to delimit it faunally, following
the suggestion of E. O. Ulrich has not resulted successfully
except in so far as it has been proved that Rhynchonella ains-
‘liei N. H. W. recurs in this part of the Stictopora bed, and
that it is the zone of the rare Leptena halli Sar. It is highly
fossiliferous. In general it bears the same relation to this
bed as the few inches of conglomeratic shales at the top of
the Stictoporella bed do to that one (see plate] X). The con-
glomerate zone in the Orthisina bed which is nearer the bot-
tom than the top, lies however at the top of a faunal zone,
which might be designated by a separate name but which
could not however be distinguished in other places, because
of imperfect preservation.

The rule is then without exception here that the sedimen-
tary small non-conformities coincide with faunal changes and
these both may be assumed to have a common cause, namely,
intervals of no sedimentation in their time. This relationship
may be useful as an aid to correlation of the related forma-
tions.

At Saint Paul and Minneapolis the strata are well pre-
served and when they are exposed by quarrying the described
phenomena can be well observed. None of the rocks, as a
rule, are altered toa vesicular texture as in the Galena series

322 The American Geologist. November, 1898

elsewhere and it should not be expected therefore that the
phenomena, which are clearly shown here, will be found as
well displayed in other places even though the conglomerates
had been widely distributed. In a few instances, however,
such. phenomena are described from other places, and quite
probably they are not uncommon.

Prof. T. C. Chamberlin described one of these erosion or
corrosion zones which is seen at Platteville in southwestern
Wisconsin. He writes ‘“The upper surface of the typical glass
rock near Platteville, shows a smooth eroded upper surface
with an occasional fracture of the upper layer through which
the subsequent deposit penetrated.”* This occurrence has
been seen by me recently, and it is found to be at the top of the
Stictoporella bed and thus corresponds to the fourth corrosion
zone at Minneapolis and Saint Paul. I have already described
the Orthisina bed conglomerate from Kenyon, Minnesota (op.
cit. p. 29), which is like that at Saint Paul. Also the oolitic
or semioolitic deposits which have been seen from Saint Paul
for 100 miles southeastward at various exposures have been
before mentioned (op. cit. p. 28). These occurrences with
possibly many others which have not yet been noted may.
prove the wide continuation of the several corrosion zones in
the lower and middle Galena (Trenton) series.

The remaining beds of the series, numbers 7, 8 and 9,
forming the typical limestone called Galena limestone in geo-
‘ogical reports is altered to a vesicular structure with many
concretions in nearly all known exposures, and it will not
therefore be readily determinable whether the recurring cor-
rosion zones continue upwards into these beds. Such may
have existed similarly or on even smaller scale than in the
lower beds. Here and there they might be discoverable in
well preserved strata. Very often in fact the rough faced
strata of the dolomytes and the irregular compressed or re-
duced shale laminz, simulate the corrosion zones. But,
again concretionary structures and limestone nodules from the
disintegration of shaly limestones might be mistaken for the
conglomerate above described when percolating water had
removed the black stain of their surfaces. Therefore it can
not be assumed that corrosion zones exist where they have

*Geol. Wis. vol. AS ps 413 and fig. 8.

Editorial Comment. 323

not been observed in good preservation. The observed rela-
tion of the corrosion zones with the upper limits of the strati-
graphic and faunal divisions or beds lends however an ad-
ditional significance to these in the upper parts of the series
and wherever they occur although unaccompanied by corro-
sion or erosion phenomena.

EDITORIAL COMMENT.

DRYGALSKI’S GLACIAL STUDIES IN GREENLAND.

The Geographical Society of Berlin has published the re-
port of its scientific expeditions to Greenland, which were
under the direction of Dr. Erich von Drygalski, in 1891, and
again leaving Copenhagen on May 1, 1892, and returning Oc-
tober 14, 1893. The work is in two volumes (pages 556 and
571, with 53 plates, lo maps, and 85 illustrations in the text;
Berlin, W. H. Kuhl, 1897). Studies of the inland ice-sheet
by Drygalski were the chief purpose of these expeditions,
the district selected for special examination being that ad-
joining the Umanak fjord.

Much attention is given in this report to the questions of
the probable configuration of the interior of Greenland,
under its thick ice-sheet, and of the physical conditions of
outflow of the ice. The processes of glacial erosion, trans-
portation, and deposition of the drift are very instructively
described and discussed; and the author’s general conclu-
sions are well summarized by Prof. James Geikie in a review
given in Nature (vol. 58, pp. 413-416, Sept. 1, 1898), as_fol-
lows:

With regard to the ground-moraine itself, there can be no question
that this is partly carried in the lower portions of the ice, and partly
pushed forward underneath, and, further, that the forward movement
must result in the deformation of underlying unconsolidated formations.
The moving force is, of course, in the ice itself. With the augmentation
of included débris the mobility of the mass is impaired, internal friction
increasing the more closely the materials are crowded together. It is
only when débris is well saturated that under pressure movements like
those of the ice itself can take place. In a compact subglacial mass of
débris the movement communicated by the flowing ice above must,

324 The American Geologist. November, 1898

owing to friction, quickly die out downwards. Only a relatively thin
laver of ground-moraine, therefore, can travel onwards underneath the
ice. Immense quantities of material, however, are interstratified with
the lower layers of the “inland ice,” and these are eventually added to
the ground-moraine, The amount of this included or intraglacial débris
depends upon the thickness of the ice, and must thus vary from place
to place. As the ice diminishes in thickness, its ability to transport
rock-materials declines, and the rubbish begins to be deposited below.
Dr. Drygalski thinks that the boulder-clays of North Germany were in
all probability deposited in this way. Thus wide sheets of boulder-clay
and the ‘“‘end-moraines” of a great ice-sheet have had the same origin—
they consist of ground-moraine accumulated under the thinner peripheral
portions of the ice.

Drygalski’s view closely coincides with the opinions
which the present writer has stated in several papers, that
the drift was chiefly transported englacially, in the lower
part of the ice-sheet, and that it was probably thence depos-
ited in large measure subglacially near the borders of the
receding ice, while another large part became superglacial
and was allowed to drop loosely on the surface. From these
thorough studies of the Greenland ice-sheet, with the equally
elaborate and valuable observations of it, as bearing on the
origin of our Pleistocene glacial drift, by Chamberlin and
Salisbury much farther north, and with Russell’s exploration
of the partly drift-covered and forest-clad Malaspina glacier
in Alaska, we obtain much aid toward a comprehension of
the conditions which attended the retreat of the great Amer-
ican and European ice-sheets. But we have yet much to
learn, and the numerous expeditions now being made in both
Arctic and Antarctic regions will doubtless still further ex-
tend and broaden our knowledge derived from present ice-
sheets as illustrating the Glacial period. W. U.

REVIEW OF RECEN® GEOLOGIECAE
De rAcl Wis:

[New Vork| Fifteenth Annual Report of the State Geologist [Prof.
JaMES HALL] for the Year 1895. Volume I, Pages 738, with many
plates, maps, and sections ; Albany, 1897.

Among the many reports that have been published by our state and
national geological surveys, this stands first, or at least in the front rank,

Review of Recent Geological Literature. 325

as to the quality of its typography and illustrations, and the sumptuously
wide margins of its pages, which make it an exceptionally ponderous vol-
ume. From the standpoint of a librarian, who must adjust his shelves
according to the size of his books, a smaller quarto or octavo form would
be more satisfactory.

The administrative report, with synopses of the work of assistants in
the field and office, relating to the geological map of the state, occupies
20 pages. In this part the reader finds the outlines of the results that
are more fully stated by these assistants in the fourteen papers which con-
‘stitute the remainder of the volume, as follows: The Stratigraphic and
Faunal Relations of the Oneonta sandstones and shales, the Ithaca and
Portage Groups in central New York, by John M. Clarke (pp. 27-81, with
7 plates of scenery, 2 geological maps, and 9g figures in the text); The
Classification and Distribution of the Hamilton and Chemung series of
central and eastern New York, Part I, by Charles S. Prosser (pp. 83-222,
with 13 plates of scenery, a large geological map, and many sections in
the text); The Stratigraphic Position of the Portage sandstones in the
Naples valley and the adjoining region, by D. Dana Luther (pp. 223-
236, with two plates, a map, and a section); The Economic Geology of
Onondaga county, New York, by D. Dana Luther (pp. 237-303, with 21
plates, 2 maps, and 12 figures); The Structural and Economic Geology of
Erie county, by Irving P. Bishop (pp. 305-392, with 16 plates, and 6
maps); Geology of Orange county, by Heinrich Ries (pp. 393-475, with
44 plates, including many maps and sections); Report on the Crystalline
Rocks of St. Lawrence county, by Charles H. Smith, Jr. (pp. 477-497):
Report on the Geology of Clinton county, by Henry P. Cushing (pp. 499-
573, with 5 plates, a county map, and geological maps of the separate
townships); Preliminary Report on the Geology of Essex county, by
James F. Kemp (pp. 575-614, with 12 plates, including a county map and
large geological maps of several townships); Sections and Thickness of
the Lower Silurian formations on West Canada creek and in the Mohawk
valley, by Charles S. Prosser and Edgar R. Cumings (pp. 615-659, with
12 plates of scenery, and 3 figures of sections in the text); Report on the
Talc Industry of St. Lawrence county, by Charles H. Smyth, Jr. (pp.
661-671); Physical tests of the Devonian shales of New York state to de-
termine their value for the Manufacture of Clay Products, by Heinrich
Ries (pp. 673-698); The Discovery of a Sessile Conularia, by R. Ruede-
mann (pp. 699-728, with 4 plates, being in large part the same as his ar-
ticles, with plates, in the American Geologist for March and April, 1896);
and Notes on some Crustaceans from the Chemung group of New York,
by John M. Clarke (pp. 729-738, with four figures in the text). A large
geological map of Albany county, onthe scale of a mile to an inch, by
N. H. Darton, is inserted at the end of this volume.

Professor Hall’s work for this state survey during more than sixty
years, with that of his associates and assistants, long ago made New
York the leader and exemplar of all other surveys on our continent in
relation to the stratigraphy, paleontology, and correlation of the Paleo-
zoic formations; and this work was continued with unabated industry and

326 The American Geologist. November, 1898

efficiency to the end of his life, as attested by this annual report. The
second volume, which is yet to be issued, will comprise Hall’s discussion
of Streptelasma and allied genera of rugose corals, and his memoir on
the Paleozoic hexactinellid sponges constituting the family Dictyospon-
gida. More than 120 species of this family, in 29 genera, are known and
will be described, with illustrations, in this memoir, more than 70 of
these species being recognized in the Chemung fauna, Wiss

Interglacial Deposits in Towa: a Symposium presented at the lowa
Academy of Sciences, Des Moines, Dec. 28, 1597. Papers by SAMUEL
CALVIN, FRANK LEVERETT, H. FosTER BAIN, and J. A. UDDEN; 41
pages, with plates 1v-vul, and two maps, reprinted from the Proceedings
of the Academy, vol. V, 1808.

Abstracts of the papers comprised in this brochure were given in
the American Geologist for April, 1898 (Vol. X XI, pp. 251-264).
Nearly .all of our American glacial and interglacial formations, so
far as they have been already somewhat fully discriminated, have
a good development within the state of Lowa; and sceverat members
of that series, as the Aftonian, Buchanan, and Iowan, are there most
typically developed, and thence derive their names. The rapidity with
which these formations have been discriminated and first published
under these names during the last four years, and the important
changes of their order required by the study of sections in Iowa,
make it very desirable to consider them in their sequence and rela-
tionships, as in these papers. According to the nomenclature pro-
posed in successive parts by Chamberlin, G. M. Dawson, Calvin and
Leverett, the series is as follows, in the order of age from the earliest
to the latest: 1. Albertan till; 2. Aftonian interglacial deposits, prob-
ably equivalent with the Saskatchewan beds; 3. Kansan till; 4. Bu-
chanan interglacial beds, with the Yarmouth zone of weathering and
erosion; 5. Illinoian till; 6. Sangamon interglacial deposits and
weathered zone; 7. Iowan till; 8. Peorian soil and associated modified
drift, including the chief mass of the loess, especially prolonged in
its deposition adjacent to the Altamont moraine in northwestern Lowa;
9g. Early Wisconsin moraines and till; 10. Later Wisconsin moraines
and till. Through this ciassification, with names of geographic origin,
the Mississippi and Saskatchewan basins become the standard of com-
parison for future studies and correlation of the North American
stages of the Glacial period, like the New York nomenclature for the
periods of the Paleozoic era. W. U.

Report on a Traverse of the Northern Part of the Labrador Peninsu-
la from Richmond Gulf to Ungava Bay. By A. P. Low. Geol. Survey
of Canada, Annual Report, vol. LX, Part L, 43 pages, with four plates;
Ottawa, 18098.

The journey of exploration here reported was made during the
summer of 1896. It included about 500 miles of travel by canoes and
over portages, the route being up the Wiachouan and Clearwater
rivers to Clearwater lake; thence north to Seal lake, tributary to
Hudson bay by the Nastapoka river; and thence by the Stillwater

Review of Recent Geological Literature. 327

and other rivers of the Koksoak system-to Fort Chimo. Thence the
party sailed in the Hudson Bay Company’s steamer to Rigolet in
eastern Labrador, and from there to Quebec in a schooner.

Laurentian granite and gneiss occupy the greater part of the area
traversed; but Cambrian strata, dolomyte, sandstone, aid cnert, border
the east side of Hudson bay at Richmond gulf, and other Cambrian
beds are found in parts of the Koksoak basin, including probably
workable deposits of magnetite and hematite.

Glacial drift, in greater or less amount, overspreads all the coun-
try. In the interor it often consists largely of pregtaciaiiy decayed
rock-material. apparently not far displaced by the -ice movement;
and many of its boulders there are probably residual masses from
such subaérial weathering and erosion. On the low grounds the till
is usually amassed in drumlins, trending approximately in parallel-
ism with the outward glaciation of the peninsula. Eskers are fre-
quent, having similar courses and running along the valleys, as in
New England.

Thirty-five terraces or beaches, of marine formation during the
Champlain epoch, the highest being 460 feet above the sea, were
crossed on the portage leaving Richmond gulf; and higher terraces,
regarded as probably also marine, occur up to an altitude of 710
feet. On the descent to Ungava bay the highest marine terraces
noted are about 620 feet above the sea level.

In Seal lake, fifty miles long and from half a mile to five miles
wide, nearly 800 feet above the sea and about a hundred miles distant
from it, either the common harbor seal (Phoca vitulina) or a closely
allied species, lives and breeds in considerable numbers, thirty or
more being killed annually by the Indians. The seals are thought to
have come into this lake during the Champlain submergence, which
must have nearly or quite connected it with Hudson bay, “‘and having
found it full of fish they probably lost the inclination to return to
the sea.” This explanation, which is doubtless true, appeals to a sim-
ple and somewhat uniform epeirogenic uplift, less complex and less
prolonged, we may believe, than the earth movements which will
be found to account for the seals and many species of marine crus-
taceans in the great Siberian lake Baikal, about 1,500 feet above the
sea and having a maximum sounding of 4,746 feet. In both these in-
stances the connection with the sea was geologically recent, in
contrast with the probably remote time when lake Tanganyika, 2,680
feet above the sea, and of undetermined depth exceeding 1,200 feet,
received its jelly-fish and numerous species of mollusks, prawns, and
protozoa, of marine derivation. Orogenic as well as epeirogenic move-
_ments, with profound crustal deformation, quite certainly shared in
separating the basins of these greater fresh-water lakes from the
ocean, giving to them a far more complicated history than that of
Seal lake, which merely participated with all the Labrador peninsula
in the general uplift from the Late Glacial or Champlain depression.

W. U.

328 The American Geologist. November, 1898

Text-book of mineralogy, with an extended treatisee on crystallogra-
phy and physical mineralogy. EDWARD SALISBURY DANA. New edi-
tion, entirely re-written and enlarged, with nearly 1000 figures and a col-
ored plate. 8vo, viii + 593 pages, $4.00, John Wiley and Sons, New
York: 1898

This work takes the place, in most elementary and classroom work,
of the “System of Mineralogy,” by Dana, of which it is, in its descript-
ive portion, an abridgment. Its physical and chemical portions, espe-
cially that relating to optical methods, are more full than the same in
the larger book, so that by this text book the modern student may be
made acquainted with nearly all the methods of mineralogical investi-
gation. It is to be commended for its adoption of the Miller system
of symbols, and for the use of symmetry as a basis of classifying all
crystal forms, making thirty-two groups. N. H. W.

Manual of Determinative Mineralogy, with an introduction on Blow-
pipe Analysis. GEORGE J. BRusH. Revised and enlarged, with entire-
ly new tables for the identification of minerals, by SAMUEL L. PEN-
FIELD. 8vo, pp. x + 312, 15th edition. John Wiley and Sons, New
York: 1898.

This excellent work is still further improved by the addition of an
entirely new chapter, devoted to the physical properties of minerals,
especially crystallography. The remainder of the introductory portion
is essentially the same as in the last (14th) edition, but the tables which
have been for a long time familiar to the American student, are ampli-
fied and altered so as to cover nearly 800 species, and the new facts of
mineralogy, their general scope and plan being the same as before.
The work therefore is no longer a treatise on blowpipe manipulation
and determination, but becomes a general manual for the determina-
tion of minerals by all methods excepting the study of their optical
characters. N. H. W.

MONTHLY AUTHORS CARA OG Riz
oF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Adams, Geo. L.

The Upper Cretaceous of Kansas. (Univ. Geol. Sur. Kans., vol. 4
Paleontology, Part 1, pp. 13-27, 4 pls., 1898 [with addenda by S. W.
Williston]).

Ashley, Geo. H.
Note on fault-structure in Indiana. (Proc. Ind. Acad. Sci., 1897,
Pp. 244-250, 2 pls. [1898]).

*This list includes titles of articles received up to the 20th of the preceding
month, including general geology, physiography, paleontology, petrology and
mineralogy.

Authors’ Catalogue. 320

Bailey, L. W.

Report on the Geology of Southwest Nova Scotia, embracing the
counties of Queens, Shelburne, Yarmouth, Digby and a part of Anna-
polis. (Geol, Sur. Can., Ann. Rept., vol. 9, 1898, 1 map, 5 pls).

Bain, H. F.(and A. G. Leonard.)

The Middle Coal Measures of the western interior coal fields. (Jour.
Geol., Sept.-Oct., 1898, vol. 6, pp. 577-588).
|S¥2) U5. 7 red oe

The Cady Marsh. (Proc. Ind. Acad. Sci., 1897, pp. 240-242 [1898]).

Bell, Robt.

Report on the Geology of the French River sheet, Ontario. (Geol.
Sur. Can, Ann. Rept., vol. 9 ,May 3, 1897 [1898], 1 map).

Bennett, L. ee

Four comparative cross-sections of the knobstone group of In-
diana. (Proc. Ind. Acad. Sci., 1897, pp. 258-262, plate of sections
[1898] ).
Blake, Wm. P.

Bison latifrons and Bos arizonica. (Am. Geol., vol. 22, Oct., 1808,
Pp. 247.)
Bownocker, J. A.

The paleontology and stratigraphy of the Corniferous rocks of Ohio.
(Bull. Sci. Lab., Denison Univ., vol. 9, May, 1898, pp. 12-40, 1 pl).

Bryson, John.

Drift formations of Long Island. (Am. Geol., vol. 22, Oct., 1898, pp.
245-247).

Case, E. C.

The development and geological relations of the vertebrates, part
3- Reptilia [Studies for Students]. Jour. Geol., Sept.-Oct., 1808, vol.
6, pp. 622-646).

Chamberlin, T. C.

A systematic source of evolution of provincial faunas. (Jour. Geol.
Sept.-Oct., 1898, vol. 6, pp. 597-608).

Chamberlin, T. C.

The influence of great epochs of limestone formation upon the
constitution of the atmosphere. (Jour. Geol., Sept.-Oct. 1898, vol. 6,
pp. 609-621).

Clark, W. B.

Report upon the Upper Cretaceous Formations. (Part 3, of the
Ann. Rept. of the State Geologist of New Jersey for 1897, pp. 161-210
[1898] ).

Claypole, E. W.

Microscopical light in Geological darkness (Am. Geol., Oct., 1808,

vol. 22, pp. 217-230).

Culbertson, Glenn.

_ Preliminary work for the approximate determination of the time
since the retreat of the first great ice sheet. (Proc. Ind. Acad. Nat.
Sci., 1897, pp. 242-243 [1898]).

330 The American Geologist. November, 1898

Dana, E. S.

A Text-book of Mineralogy, with an extended treatise on crystal-
lography and Physical Mineralogy [New Edition], 1808. John Wiley
& Sons, New York, pp. 593, I pl., 1008 figs.

Darton, N. H. (and Arthur Keith.)

On dikes of Felsophyre and Basalt in paleozoic rocks in Central
Appalachian Virginia (Am. Jour. Sci., ser. 4, vol. 6, pp. 305-315, 1808).
“Dawson, Wm. L.

Glacial Phenomena in Okanogan county, Washington. (Am. Geol.,
vol. 22, Oct., 1808, pp. 203-217).

Falrbanks, H. W.

Geology of a portion of the southern Coast ranges. (Jour. Geol.,
Sept.-Oct., 1808, vol. 6, pp. 551-576).

Ramehila: ki.

Kettles in Glacial Lake deltas. (Jour. Geol., Sept.-Oct., 1898, vol. 6,
PP. 589-596).

Haworth, Erasmus.

Annual Bulletin on the Mineral Resources of Kansas for 1897, pp.
98, 18 pls. (The University Geological Survey of Kansas, Lawrence,
July, 1898).

Hidden, W. E. (and J. H. Pratt.)

Twinned Crystals of Zircon from North Carolina. (Am. Jour. Scti.,
ser. 4, vol. 6, pp. 323-326, 1808).

Hoffman, G. Christian.

Report on the section of chemistry and mineralogy. (Geol. Sur.
Can. Ann. Rept., vol. 9, 30 June, 1808).

Jenkins, Geo. E.

Supplemental Notes on the Mining Industry of New Jersey. (Part
6 of the Ann. Rept. of the State Geologist, pp. 317-357, for 1897 [1898]).
Jones, Lee H.

The upper limit of the Knobstone group in the region of Borden.
(Proc. Ind. Acad. Sci., 1897, pp. 257-258 [1808]).

Keith, Arthur (and N. H. Darton.)

On dikes of Felsophyre and Basalt in paleozoic rocks in central
Appalachian Virginia (Am. Jour. Sci., ser. 4, vol. 6, pp. 305-315, 18908).

Keyes, C. R.

Eolian Origin of the Loess (Am. Jour. Sci., Ser. 4, vol. 6, 1898, pp.
299-304).
Kummel, Henry B.

The Newark System or Red Sandstone belt. (Part 2 of the Annual
Report of the State Geologist of New Jersey for 1897, pp. 23-159, 8 pls.
| r898]).

Leonard, As Gal(and (Hb Bains)

The Middle Coal Measures of the western interior coal fields. (Jour.

Geol., Sept.-Oct., 1898, vol. 6, pp. 572-588).

Authors’ Catalogue. 3

Loe)
ar

Logan, W. N.
The invertebrates of the Benton, Niobrara and Fort Pierre groups
(Univ. Geol. Sur. Kans., vol. 4, part 1, pp. 429-518, 34 pls., 1808).

Low, A. FP.

Report of a traverse of the northern part of the Labrador penin-
sula from Richmond gulf to Ungava bay (Geol. Sur. Can., Am. Rept.,
vol. 9, 12 Jan. 1808, 43 pp. 4 pls.)

McClung C. E.

Microscopic organisms of the Upper Cretaceous. (Univ. Geol. Sur.
Kans., vol. 4, part I, pp. 416-428, 1 pl., 1808).

Newsom, J. F.

A Geological Section Across Southern Indiana, from Hanover to
Vincennes, (Proc. Ind. Acad. Sci., 1897, pp. 250-253 [1898]).
Newsom, J. F.

The Knobstone Group in the region of New Albany (Proc. Ind.
Acad. Sci., 1897, pp. 253-256, map [1898]).

Ordonez, Ezequiel.

Les Volcans Colima et Ceboruco. (Mem. Soc. Alzate, Mex., tome 9,
PP. 325-333, 1898).
Pratt, J. H. (and W, E. Hidden.)

Twinned crystals of Zircon from North Carolina. (Am. Jour. Sci.,
ser. 4, vol. 6, pp. 323-326, 1898).
Price, J. A.

Notes on Indiana Geology. (Proc. Ind. Acad. Sci., 1897, pp. 262-266.
1 pl. [1898]).
Salisbury, Rollin D.

Surface Geology [New Jersey]. (Part I. of the Annual Report of
the state geologist of New Jersey for 1897, pp. 1-22, with a prelimi-
nary map of the surface formations of the state [1898])

Shimek, B.

Is the loess of aqueous origin? (Rep. Iowa Acad. Sci., 1897, pp
5-18 [1808]).
Smock, John C,

Administrative Report of the Geological Survey of New Jersey for
1897 [1808].
Spencer, L. J.

Diaphorite from Montana and Mexico. (Am. Jour. Sci., ser. 4, vol.
6, p. 316, 1898).
Upham, Warren.

Geology and Geography at the American Association meeting
[1898]. (Am. Geol., vol, 22, pp. 248-255, Oct. 1898; also, Science, N.
S., vol. 8, Oct. 7 and 14, 1808).

Upham, Warren.
Glacial rivers and lakes in Sweden. (Am. Geol., vol, 22, Oct. 1808,
Pp. 230-235).

332 The American Geologist. November, 1898

Veatch, Arthur C.
An old river channel in Spencer county, Indiana, (Proc. Ind. Acad. °
Sci., 1807, pp. 266-271 [1808]).
Vermeule, C. C.
Drainage of the Hackensack and Newark Tide-Marshes. (Part 5
of the Ann. Rep. State Geologist of New Jersey for 1897, pp. 207-316
[1898] ).
Walcott, Charles D.

Note on the brachiopod fauna of the quartzitic pebbles of the Car-
boniferous conglomerates of the Narragansett basin, Rhode Island.
(Am. Jour. Sci., ser. 4, vol. 6, pp. 327-328, 1808.)

Walcott, C. D.

Eighteenth annual report of the Director of the United States
Geological Survey, 1806-97 [1807], pp. I-130, 2 maps.

Whitten. W. M.

Quicksand pockets in the blue clay of South Bend. (Proc. Ind.
Acad. Sci., 1897, pp. 234-240 [1898].)

Williston, S. W.

Addenda [to the article by Geo.L. Adams onthe Upper Creteceous
of Kansas]. (Univ. Geol. Sur. Kans., vol. 4, part I, pp. 28-32, 1808.)
Williston, S. W.

Birds [fossil in Kansas]. (Univ. Geol. Sur. Kans., vol. 4, part 1,
PP. 43-53, 4 pls., 1898.)

Williston, S. W.

Dinosaurs. (Univ. Geol. Sur. Kans., vol. 4, part 1, pp. 67-70, 1 pl.,
1808. )

Williston, S. W.

Crocodiles [fossil in Kansas]. (Univ. Geol. Sur. Kans., vol. 4,
part I, pp. 76-78, 1808.)

Williston, S. W.

Mosasaurs. (Univ. Geol. Sur. Kans., vol. 4, part 1, pp. 84-221, 62
pls., 1898.) ;
Winchell, H. V.

On the occurrence of cubanite at Butte, Montana. (Am. Geol.,
vol. 22, Oct. 1808, p. 245.)

Winchell, N. H.

Note on the characters of mesolite from Minnesota. (Am. Geol.,
vol. 22, Oct. 1898, pp. 228-230.) .

Wolff, J. E.

Occurrence of native copper at Franklin Furnace, N. Y. (Proc.
Am. Acad. Arts and Sci., vol. 33, pp. 429-430, June, 1808.)
Woolman, Lewis.

Artesian Wells in New Jersey. (Part 4 of the Ann. Rept. of the
State Geologist of New Jersey for 1897, pp. 211-296 [1808]).

Correspondence. 333

CORRESPONDENCE.”

GLACIAL OBSERVATIONS IN THE CHAMPLAIN-ST. LAWRENCE VAL-
LEY. Two points of considerable interest came under my observation
during a recent excursion in Canada.

ist. A Buried .Channel in the Valley of the Maskinonge
River—This stream enters into lake St. Peter from the north, about
seventy miles below Montreal. The line of hills which forms the
border of the old Laurentian continent, is about fifteen miles back,
and forms a well-defined line visible from the river through the entire
distance. A well-defined terrace, rising about fifty feet from the river,
is encountered about two miles inland. From this point on to the
Laurentian hills there is a gradual rise over an even surface of boulder

clay until an elevation of something over two hundred feet is reached
at the base of the hills. This glacial deposit is deeply eroded.

Where the river breaks through the Laurentian barrier it descends
by a waterfall nearly two hundred feet high, and finds its way into a
preglacial valley running at right angles to the fall, the river itself hav-
ing turned abruptly to enter the gorge. This preglacial gorge was
found to extend about a mile northward with very little glacial de-
bris filling it. At this point, however, it was entirely filled with
glacial debris, which forms a complete obstruction. For several miles
above as far as to Rousseau Platte the stream is very sluggish, while
the banks and the bottom are of sand and clay. But so extensive are
the deposits of modified drift that it was impossible to tell just where
the buried channel was or how far up it extended. The whole condi-
tion of things, however, furnished a striking and fresh illustration of
the now well-established law that in the glaciated region a waterfall
is sure indication of a buried channel in the near vicinity. Indeed it
was not difficult to recognize in the gentle inclinations of the sides of
this preglacial valley the enormous lengths of time during which pre-
glacial rivers had been doing their work, nor in the small amount of
erosion at the present site of the waterfall, the very limited time during
which the stream had occupied its present channel. For the privilege
of making these observations I am indebted to the kindly interest of
Messrs. Frank Wing and C. H. Simpson, of New York city, who have
summer residences in that region.

and. Lateral Moraines near. Plattsburgh, N. VY. —Mr.S. Prentiss
Baldwin in his paper in the American Geologist (vol. xiii., p. 181), al-
ludes to a possible terminal moraine in Altona township, Clinton
county, N. Y., about ten miles northeast of Plattsburgh. Here there
are three or four well-defined parallel lines of morainic deposits just
above the level of the highest terrace of the Champlain epoch, which
is here about four hundred feet above the sea. I had the privilege of
being conducted over the region by Dr. D. S. Kellogg and Prof. Hud-
son, of the Normal school. Our observations led us to conclude that
these deposits could more properly be called lateral than terminal mo-

-

334 The American Geologist. November, 1898

raines; while one of the ridges seemed to us like a much-prolonged
drumlin such as those that characterize central New York. The direc-
tion of the ridges of till is northeast and southwest, corresponding
both to the direction of the scratches upon the rocks and of the strike
of the strata of Potsdam sandstone forming Rand hill, which rises to a
considerable hight to the west. The facts as we saw them were of
special interest from their bearing upon the discussion of Prof.
Spencer’s paper at the American Association meeting in Boston in
which he maintained that it was necessary to suppose a subsidence of
fiiteen hundred or two thousand feet to account for the horizontal
terraces found at the various elevations upon the flanks of both the
Green and the Adirondack mountains. But these lateral moraines in
Altona indicate the true explanation.

It seems evident that in the decline of the glacial period the abla-
tion of the ice from the surface in this region led at a certain period
to the appearance of the tops of these mountains as lines of nunataks, :
while the Champlain valley was still full of ice. As the ablation pro-
ceeded, the effect of these lines of nunataks on either side was to keep
the margins of the ice lower than the middle. This would naturally
result from their influence in absorbing and reflecting the heat. From
this resulted a gradual working of the glacial debris toward the mar-
gin, where it was variously modified by the streams of water which
were running between the sides of the ice and the mountains, much as
is illustrated in one of Prof. Russell’s photographs from the Malaspina
glacier. In this way these high-level horizontal terraces in Vermont,
described by Prof. Spencer, would be formed without the extensive
subsidence which he supposes. And Mr. Baldwin is doubtless correct
in believing that Baron De Geer has, on account of the same mistake,
placed the extent of the subsidence at St. Albans, Vt., at two hun-
dred feet more than it really was. Mr. Baldwin’s account, on page 176
of the paper already referred to, of the typical moraine terrace 560
feet above the sea at Crown Point, appears to be a striking confirma-
tion of this interpretation of the facts.

It may be well to note, in this connection, that the discovery by
professors Hitchcock and Richardson of Canadian boulders near the
summits of the Green mountains, and far up upon the flanks of the
Adirondacks, would seem to settle the question which has been in dis-
pute between some of the Canadian geologists and those upon this
side of the line respecting the actual invasion of the Champlain valley

by Canadian ice. i
G. FREDERICK WRIGHT.

Oberlin, Sept..23, 1898.

WHATS OSS FOL 77 BR

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SN NN

GEOLOGICAL MAP

GouTER GREEN |.

MAP OF MAINE

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CASCO BAY MAINE

SHOWING POSITION OF DIKES

BY
E.C. E.LORD

CAPE ELIZABEITH LT

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BASIC
DIKES

2
ACcIO

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L HURONIAN
DEPOSITS SCHISTS DIKES

GLACIA

RECENT
SAND

THE

AMERICAN GEOLOGIST.

Wor: OTT. DECEMBER, 1808. No. 6

Shei OLleces IN HE, .VICINITY OF PORT-
LAND, MAINE.
By E. C. E. Lorp, Washington, D. C,
(Plate X.)

Along the coast of Maine trap dikes are very abundant.
In his “Geology of Northern New England,’ professor
Hitchcock mentions the following localities: Mount Desert,
Marshall, Little Deer Island, Vinal Haven, Hancock, Ells-
worth, Bluehill, Brookville, Rockland, Thomaston, Hope,
Whitehead island, Windham, Limerick, Gorham, Casco bay
and Portland. ;

Professor G. P. Merrill in describing the Maine building
stones* refers at length to diabase from Addison Pt., Indian
river and Vinal Haven. Other localities from which similar
rock has received detailed study are: St. Georget, Seward’s
island in Frenchman’s bay,t Kennebunkport,$ Lewiston and
Auburn || and the Fox islands.

The region to be described in this paper embraces a part

*Proceedings of the United States National Museum, Vol. VL.,
No. 12, 1883.

+Q. E. Dickerman and M. E. Wadsworth: On Olivine Bearing
Diabase from St. George, Me. Proc. Boston Soc. Nat. Hist., Vol.
MOREE. sp. 28:

+W. O. Corsby: Geology of Frenchman’s Bay, Me. Proc. Bost.
Soc. Nat. Hist., 1880, p. 109.

§J. E. Kemp: Onthe Dikes near Kennebunkport, Me. Amer. Geol.,
Vole V4 1890)"p. 120:

|| George P. Merrill: On Some Eruptive Rocks in the Vicinity of
Lewiston and Auburn, Androscoggin Co., Me. Amer. Geol., Vol.
X., 1892.

§ G. O. Smith: The Geology of the Fox Islands, Me. Dissert.
Inaug. Johns Hopkins University, 1806.

330 The American Geologist. December, 1898

of the Casco bay, and the southern portion of the Freeport
quadrangle of the United States Geological Survey.

The fjord-like character of the bay with excessively in-
dented coast-line, and the effects of glaciation on the islands
are well brought out on the map.

The trend of the islands is northeast, and corresponds with
the strike of the crystalline schists composing them. These:
schists are, according to Hitchcock,* of Huronian age, and
extend from near Saco river to Harpswell, abutting against
gneiss (Laurentian) on the east, and are overlain to the west
and northwest by strata of Cambrian age.t They consist of
finely stratified micaceous quartzytes, biotite, chlorite, and
actinolite schists, merging locally into garnetiferous and staur-
olitic varieties. These strata are undoubtedly of clastic ori-
gin, but their original structure is in many cases almost totally
destroyed by the far reaching effects of a regional metamor-
phism. They have a remarkably regular N. 50°—6o0° E.
strike, and are generally inclined at high angles to the north
or south. Cleavage is especially well developed in the fine
grained micaceous schists forming the greater part of the
series. On weathered surfaces this rock bears frequently
quite a striking resemblance to irregularities of surface of de-
caying, coarse-grained timber, and breaks up locally in long
thin layers, not unlike fence rails. A slab, showing this pecu-
liar form of weathering, is figured in “Rocks, Rock-weather-
ing and Soils,’ by Prof. G. P. Merrill, MacMillan & Com-
pany, 1897. In describing it (page 248) the author says:

“The finely fissile schists, standing nearly on edge along
the coast of Casco bay, in Maine, under the combined in-
fluence of wave and atmospheric action, weather into peculiar
fantastic forms resembling nothing more than piles of lumber
in which multitudinous channels formed by boring coleopter-
ous larve have become irregularly enlarged by decay.”

Apart from-secondary folding and some local shearing and
faulting the schists show evidence of considerable jointing sub-
sequent to the intrusion of the dikes. The jointing affects the

*Chas. H. Hitchcock: The Geology of Portland, Me. Proc. Amer.
Assoc. Adv. Sci., Vol. X XII., 1884, p. 164.

+See geological map of Maine. C. H.. Hitchcock: Geology of
Northern New England, 1885, p. 5.

Dikes near Portland, Maine. —Lord. 337

schists and dikes alike, and consists of two systems of ver-
tical fractures intersecting each other at an angle of about 30’,
and causes the rock to break down in rhomboidal blocks
when exposed to the direct action of the waves. The schists
are overlain at various points by glacial deposits, and fre-
quently along the shore considerable stretches of beach sand
are met with. This sand is ordinarily of the common white
variety, consisting principally of quartz with some feldspar
fragments and flakes of mica, but occasionally it is colored
brownish red, owing to local accumulation of rounded garnet
crystals.

The glacial deposits are especially well developed at Port-
land and a point on cape Elizabeth, about two miles south of
the city. They consist of basal, or lower boulder clay, com-
posed chiefly of large, highly striated rock-fragments, and of
an upper, looser, brownish-red till, which at Portland merges
at the top into gravel beds.

This glacial debris has been removed to a great extent
from the islands in the bay, especially from those immediately
facing the ocean. Even great Chebeag island, having a
somewhat protected position, is but lightly covered with
gravel and boulders.

The low, flat islands of the inner bay (Mackey, Clapboard
and Basket islands) are composed of reassorted glacial ma-
terial similar to that forming the marine terrace which fringes
the adjoining coast.

The study of the basic dikes about Portland was taken up
to discover. what relations, if any, exist between them and the
diabasic intrusions of Kennebunkport and Bald Cliff, and, if
possible, to ascertain the nature of the parental mass from
which they originated. The prosecution of the work devel-
oped many features of special petrographical interest.*

These basic dikes occur on the islands of Casco bay, and
the eastern shore of cape Elizabeth, and can be followed as
far south as Prout’s neck, some three miles beyond the limit

*The work was carried on in the petrographical laboratory of the
U. S. National Museum in Washington, D. C., and the writer wishes
to acknowledge his thanks for facilities offered, and the privilege of
studying the collections. He is especially indebted to professor G. P.
Merrill, head curator, Dept. of Geology, in the museum, for many
ee suggestions, and to Dr. Thomas L. Watson for advice and
aid.

338 Lhe American Geologist. December, 1898

of the area studied. They form a very conspicuous feature
of the coast, partly on account of their dark color, which gen-
erally stands oyt in strong contrast to the lighter gray tints
of the schists, but especially owing to the fact that they
weather out more rapidly than the surrounding rock, leaving
straight channels with vertical walls to mark their original
location.

They belong, with a single exception, to one general series
with a very persistent N. 55° E. strike, and essentially vertical
dip. This conformity in strike with that of the schists is in-
dicated on the map. These dikes rarely exceed six feet in
thickness, and are usually from only two to four, but they
frequently can be traced for considerable distances along the
coast; thus No. 14, at Broad cove, cape Elizabeth, possessing
peculiar mineralogical characteristics, is easily recognized
again on Bailey’s island, a distance across the bay of nearly
fourteen miles.

The exception referred to is a dike 80 feet thick, of a
coarse grained enstatite-diabase-porphyry, occurring on the
eastern side of Cousin’s island, and extending across the
southern end of Littlejohn’s island in a general easterly di-
rection.

The prevailing character of these intrusions is dense por-
phyritic, with occasional coarser crystalline varieties, depend-
ing upon the physical conditions under which the rock-mag-
ma solidified. The walls of the dikes in direct contact with
the schists are aphanitic, and in some cases almost vitreous,
whereas in the central portions, especially of the larger dikes,
a coarser texture prevails. Even granular varieties are not
irequents 7G, 31O;.177 24120))

The mineral composition of the rock in general is that of
olivine-diabase-porphyry, consisting of olivine, augite, plagio-
clase and magnetite. Subordinate types, containing as diag-
nostic constituents enstatite or hornblende, will be classed as
enstatite-diabase-porphyry and camptonyte respectively.

Previously to the intrusion of the diabase and camptonyte
occurred that of granitic rock. A large pegmatyte dike (32)
with aplitic extensions (31) forms a part of the western shore
of Biber’s island, and can be followed in a northeasterly direc-
tion through Pettingill’s, Williams’ and Sister island to Mare

Dikes near Portland, Maine.—Lord. 330

point on the mainland. The walls of this dike have been ren-
‘dered in places quite schistose by extensive lateral pressure.
‘The rock is very coarse grained and shows macroscopically a
beautiful graphic intergrowth of quartz and feldspar. On
microscopical examination this feldspar is seen to be
microcline, penetrated by irregular lamellz of albite. Be-
sides quartz and this microcline (perthite) the rock contains
some muscovite, and a few grains of accessory apatite.

The aplyte is a white, even granular rock with peculiar
saccaroidal texture, and consists mineralogically of micro-
cline, orthoclase, albite, muscovite, garnet and apatite. The
garnet is in the form of very regular octahedra of a light pink-
ish color.

Examples of olivine-diabase-porphyry are from dike 1, 2,
een tO. Tt Tt rA, 15, 10,17, to, 1,20) 21, 22,23, 24,
26, 20, 30.

The specimens vary in color from steel gray to bluish
black. On exposed surfaces they weather brown. The habit
of the rock is in general basaltic with phenocrysts of olivine.
feldspar, augite, magnetite and irregularly shapped masses of
pyrite. With the aid of the microscope, the ground mass re-
solves into a panidiomorphic aggregate of augite, lath-shaped
plagioclase, magnetite and apatite. It is in every instance
holocrystalline, although frequently the rock itself appears on
exposed surfaces to be scoriaceous, owing to cavities having
been formed by the decomposition and leaching out of the oli-
vine phenocrysts.

The ofvine is exclusively of intratelluric origin, and, when
well preserved, the characteristic planes 100, 110, 021 could be
easily identified. (7, 10, 21, 22, 24, 26.) . Frequently, how-
ever, products of decomposition obliterate the crystal form,
leaving in place of the crystal a fibrous aggregate of sepen-
tine, accompanied in many cases by calcite and epidote. The
amount of olivine varies considerably in the different speci-
mens.

The augife is the most important mineral constituent of
these rocks. The crystals are either prismatic in form with
octagonal cross-sections, owing to equal development of I10,
with o10 and 100, or they are somewhat tabular formed by the
pinacoid o10. Twinning after this face is not uncommon.

340 The American Geologist. December, 1898

The crystals vary in color from, purplish brown to light yel-
lowish green; the former being the most common, and de-
cidedly pleochroitic: purplish brown parallel to qa and bp,
pale yellow parallel to ¢. Absorption is strong:-a> b> c¢.

These crystals are rarely homogeneous; they have usually
the well-known hour-glass structure in which the lighter col-
ored inner part of the crystal, with the optical properties of
diopside, is surrounded by a purplish rim of titaniferous aug-
ite resembling optically the egyrine-augite of Rosenbusch.
On sections parallel to the plane of symmetry this outer rim
shows a very strong dispersion of the bisectrices (the angle
c:¢$ > c: Cv ) anda large angle of extinction (the angle
c: €== 57°) against only 51 degrees, measured in the same
way, for the inner portion.

The pale yellowish green variety of augite is confined ap-
parently to dikes of somewhat andesitic character (3, 5, 6, 10,
12, 13, 15, 16, 17, 18, 19, 21, 25), containing an abundance of
plagioclase with but comparatively little olivine.

This pyroxene is optically identical with the diopside cen-
ter of the titaniferous augite.

The augite breaks down readily into chlorite and limonite
(6, 10; 14, 15; 16, 18):20;, 21), and in some instances iiwsene—
placed by a yellowish brown mica (12, 17, 25), with strong
pleochroism:—brownish yellow parallel to oo1, pale yellow
perpendicular to oot.

The formation of this secondary biotite proceeds usually
from the exterior inwardly along the prismatic cleavage cracks
of the pyroxene—as is clearly demonstrated in dike 12—but
occasionally it is confined to the central portion of the crystal
only, leaving the outer part perfectly fresh (12).

The plagioclase varies but little in form, and in optical
properties—the phenocrysts being stout, tabular, formed after
o10 in the coarser grained rock, and thin lath-shaped in the
groundmass and in denser varieties. The crystals are fre-
quently polysynthetically twinned in accordance with the al-
bite law, and have on O10 sections an average extinction angle
of 20 degrees, which, with a specific gravity of 2.70, would
place them in the group of normal labradorites (abs ans). In
a few coarse grained dikes of camptonitic character (1, 2, 20,
25, 30), the feldspar has a smaller angle of extinction, approxi-
mating that of anorthoclase.

Dikes near Portland, Maine.—Lord. 341

Under normal conditions the labradorite is, excepting the
olivine, the first constituent to undergo decomposition. In
one dike, however (14), it was found remarkably fresh, while
the augite and olivine were completely decomposed. The
alteration products are kaolin, calcite, and in one instance,
chlorite (18).

Magnetite in the form of well developed octahedra, or as a
delicate net-work of skeleton crystals (13) is very abundant.
In some rock specimens this mineral is altered to leucoxene.

Apatite is of normal prismatic development, and quite
plentiful in most slides.

The even granular dikes (7, 10, 17, 24, 26) differ solely in
structure from the porphyritic varicties. The mineral devel-
opment is, with the exception 10 and 24, panidiomorphic, like
the ground mass of the diabase porphyry. In 10 and 24, the
augite occurs partly as interstitial filling, thus giving the
specimens a somewhat ophitic structure.

Enstatite -diabase - porphyry (27, 28) is a coarse grained
porphyritic rock differing from the olivine-diabase-porphyry
chiefly in the preponderance of pyroxene over other constitu-
ents, and by the occurrence of enstatite in place of olivine.
The augite of this rock is pale green resembling very closely
the diopside of the andesitic types of diabase-porphyry. (See
page 340.)

The crystals of enstatite are of beautiful prismatic devel-
opment, and have the weak double refraction common to
this mineral. They vary in length from 1 to 4 mm, and are
nearly quadratic in cross-sections, owing to the predomin-
ance of oro and 100 over the prism 110, which truncates the
edges of the crystals. Cleavage parallel 110 and o10, and
parting planes approximately normal to the prism axis are
common features of this mineral. Along these planes chlor-
itization is in many cases far advanced (27).

The chemical composition of this rock (28) is given under
I, and for comparison that of augite-porphyryte is reproduced
from professor Kemp’s paper.*

id IT.
SiO a5 ry aioe eR ee iON tae eeeeees 50.76 51.93
JS EA © ER oOo A) nisi UE As tr ar i Ae Fh 0a 12.83 18.13

*Op. cit., p. 138.

342 The American Geologist. December, 189%

Ia © Fined Seer AT SHEeNG Coben SeOAcmane oq vock ce 4.98 8 g2
1SH=| © PaaOee Semen one neces aoa wees nae TOVOQ*) eo hee
AIL © Ti ae eer eats apt SNE) S Rts a cet en en Sa 6.67 5-30
Sr ©) Pere rick en cists cores eta eax cen 9.88 9.82
Nias 0 RAs OUR pt rie conics .wabratterteearet teeters 3.52 4.34
LOO Nhe a SHC aah Teeter CACC EO daneenE Gtr .62 1.42
JST @ Ree Aer iota st AR ER OEE Siete rece canes die .87 69

100.22 100.75

The chemical similarity of these rock-types is apparent.
The augite-porphyryte, or diabase-porphyry as it has been
called in this paper, is somewhat richer in alkalies and alum-
ina, and poorer in iron and magnesia than the enstatite-dia-
base-porphyry, which can be explained by considering the
fact that the latter rock contains relatively less feldspar, and
more ferromagnesian constituents than the angite-porphy-
ryte.

Camptonyte is represented by dike 8 and g. This rock
has formed the topic of considerable discussion since it was
first described by Hawes* under the name of dioryte. The
broader significance of the term as applied by Rosenbuscht
has been modified by American authors—notably Kemp and
Marstersi—to embrace only such varieties of diabasic dike-
rock in which hornblende predominates. An appreciable
amount of augite gives rise to an intermediate type—augite-
camptonyte.§

Adopting this latter classification we have but one dike
of true camptonyte (8), No. 9 being augite-camptonyte. The
camptonyte dike (8) occurs at Portland head-light on the east
coast of cape Elizabeth, cropping out again on the western
shore just beyond the map border. It is about six feet thick,
stands almost vertical and has the prevailing N. 55° E. strike
of the adjoining dikes.

*G. W. Hawes: On a Group of Dissimilar Eruptive Rocks at
Campton.N. Ee -Am: Jour Sci-9 Ser: Til Vol. xeViblee para:

+H. Rosenbusch: Massige Gesteine, 3te Auflage, pp. 535-550. Stutt-
gart, 1896.

tJ. F. Kemp and V. F. Marsters: The Trap Dikes of the Lake
Champlain Region, Bull. 107. “U.S. Geolog. Survey, p: 30:

§For literature on camptonyte see V. F. Marsters: Camptonite and
Other Intrusives of Lake Memphremagog. Amer. Geologist, Vol.
16, 1895. Page 35-36.

r

Dikes near Portland, Maine.—Lord. 343

The rock is of a bluish-black color and porphyritic struc-
ture containing some phenocrysts of serpentinized olivine, be-
sides a small scattering of purplish brown augite, magnetite
and pyrite.

The ground mass consists of idiomorphic brown horn-
blende, anorthoclase, magnetite and the decomposition pro-
ducts, chlorite and calcite.

The hornblende crystals are of prismatic development,
rarely exceeding I mm in length. They have strong pleo-
chroism in brown and yellow tones (¢c>b>a), and the
small angle of extinction common to barkevicyte —the angle
c¢:c= II degrees in maximo.

These minute amphibole needles contain in some instances
the remnants of partially resorbed augite with similar crys-
tallographic orientation—thus clearly demonstrating them to
be, in part at least, of paramorphic origin from the augite.

In order to compare the chemical composition of this
barkevicitic hornblende with that from Barkevik, large phen-
ocrysts were extracted from the camptonyte from Campton
Falls, N. H.,* and analyzed (I). No. II is an analysis of bark-
evicite given by Brégger from augite-syenite near Barkevik
(Skudesundsskjar).7

Aig ET:

SwlO}s cS SOR Se OAT Ie Cee ae eee 37.80 ( 42.46
TIO) ad ARBs eae amie Seg ROAR ARCA) Chaar
EMO RAS ce RS oo) WoK le faves Oka ones 12.89 Ties
PLD gta eke ts a od oa st oe Po as 6.14 6.18
IO!) sp Oe Se, Sitar a eran ey eae 12.55 19.93
UP ia Ore rar etre a sei. Arta: <' lala Sete sical cree acsiacs.% 0.75
CoS 16 oe ee ae 13.64 10.24
NLT 1 Io Ea gS oA i 4.10 Dele
Mica R sees ease dee a0 ofc t dice ees tc 5.26 6.08
Pelee eaten chs eee aN so eae 6 3.24 1.44

100.16 99.64

spec. pr. 3.47 Spec. gr. 3.43
No. II is seen to contain 6.39 per cent. MgO+CaO and
1.80 per cent. K:O less than No. I, but the main difference lies

*This material was obtained from a specimen of the original dior-
yte of Hawes in the collection of the U. S. National Museum.

7See P. Hintze: Handb. der Miner. Leipzig, 1893, p. 1257.

344 The American Geologist. December, 1898

in the iron (FeO) of which the hornblende from Barkevik
has 7.38 per cent. more than the brown amphibole from
Campton Falls, N. H.

The anorthoclase crystals are lath-shaped parallel to a,
and show in places a tendency to radial arrangement. They
are characterized optically by a small angle of extinction
(the angle a: A=ca.10°), which renders them easily distinguish-
able from the labradorite of the diabase-porphyry. Polysyn-
thetic twinning could not be identified—the crystals being ap-
parently single individuals.

The anorthoclase decomposes readily to calcite and kaolin.

An analysis of this feldspar (I) was made from dike 8.
The material was completely separated by means of the Thou-
let solution and afterwards exposed to a strong magnetic cur-
rent whereby many fragments containing inclusions of horn-
blende or magnetite were removed. For comparison are
given under IT the analysis of anorthoclase from the ““Rhom-
benporphyr” of the Christiania region (Tyveholmen)* and un-
der III that of murchisonyte from an augite-syenite dike near
Ula, between Sandfjord and Laurvik, South Norway.t No. IV
is the analysis of the camptonyte (dike 8), and V and VI those
of enstatite-diabase-porphyry and augite-porphyryte, already
given on page 341.

I II INE INA V VI
SiON eorhe pee seen S734). S015 7) OAOOk" 45.20) SOR OmmESIgs
SL @ eenniree rman stems, Sia Ei car AL DAN py te O08.) <a eee
ANIA @ yy OPA oa nc oreto A740), LAA SO) SORE Mist AAR TS
Hie, Og crate oper bere 2.88 2.47 890 5.98 4.98 8.92
FEO) sevocsietes epee ine Mopac real eters Pea epee re G2155) 0 LOL OO Mmsaeente
CaO pe ats teenie eee 4.27 5.05 1.19 7.80 9.88 9.82
IIE @ Pee ead iti cenit ihe 8 16 AD ere is 5.20 6.67 5.30
Nias Of -Lae See ee 8.09 6.38 7.26 4.23 B52 4.34
KG Ol tas cae once 4.17 2.50 5.84 2.31 .62 1.42
Ul O erirrrreen oka bn 2.66 1.34 0.29 5-35 .87 69

100.36 100.36 99.84 100.60 100.22 100.75

On glancing over the first three analyses it is apparent
that No. 1, although about 3 per cent. richer in alkalies, and

*See Mugge: Jb. Min., 2, p. 107, 1881.
+W. C. Brogger: Mineralien der sudnorweg. Angit-syenite. Zeit.
fiir _Kryst. von P. Groth, Leipzig, 1890, Vol. 10, p. 546.

Dikes near Portland, Maine.—Lord. 345

containing nearly 2 per cent. less Ak Os, and SiO: than the
anorthoclase from Tyveholmen (II), is much closer related to
this variety of feldspar than to the murchisonite from Ula
(III). It appears that the latter mineral, from its high per-
centage of SiOz (64.96) and K:O (5.84) combined with but
I.Ig per cent CaO, contains a larger amount of the ortho-
clase molecule than either of the other two.

The chemical relationship of the camptonyte (IV) to the
augite-porphyryte from Kennebunkport (VI) is closer than
that of the enstatite-diabase-porphyry (V) which occupies in
a certain sense an intermediate position between these two,
although containing more ferrous iron and magnesia.

From what has been said it appears that the basic dikes
in the neighborhood of Portland vary in mineral composition
from an enstatite-diabase-porphyry, containing enstatite, diop-
side, plagiociase and magnetite, to a camptonyte, composed of
olivine, hornblende (barkevicite), anorthoclase, and accessory
augite.

These basic intrusions are almost in a direct line of strike
with those from Kennebunkport and Bald cliff, and as the
main rock-types from the three areas are (with the single
exception of the enstatite-diabase) essentially identical miner-
alogically and chemically, there seems scarcely any doubt of
their genetic relationship.

The chemical affinity of the brown hornblende and anor-
thoclase of the camptonyte, with the barkevicite and soda-
feldspar of augite-syenite from Norway has been pointed out
(see pages 343-344), and it istherefore possible that some
at least of the basic dikes from the Maine coast are offshoots
from an underlying parental rock of this description. It
is suggestive in this connection to note the occurrence of large
inclusions of augite-syenite in a camptonyte dike from Kenne-
bunkport.*

This syenite is of a pinkish gray color, somewhat mottled,
owing to dark areas of magnetite and augite scattered through
the flesh colored, granular feldspar. Originally the rock
was composed of orthoclase, green augite (diopside) with
some magnetite and apatite, but subsequent fusion and re-

*Probably dike 64 of Kemp. Op) cit, Dp: Ist.

340 The American Geologist. December, 1898

crystallization of the pyroxene and adjoining feldspar have
caused some rather remarkable changes. The products of
regeneration are confined to the dark areas, and consist of
lath-shaped anorthoclase, purplish brown augite needles and
beautifully developed magnetite octahedra, besides the cor-
roded remnants of the diopside.

These newly formed minerals resemble very closely those
of the camptonyte proper and frequently, on the contact,
grade into them imperceptibly.

This rather unusual assimilation of a foreign inclusion by
an intrusive magma, might perhaps speak for a chemical
affinity between the two rocks.

Regarding the age of these intrusions little can be said
with any degree of certainty. It would seem from general
appearances in the field that the acid dikes are of greater age
than the basic intrusions—as is the case at Kennebunkport.
On the Fox islands, however, somewhat further north, Dr.
Smith (op. cit. p. 64) has found this order to be reversed.
Here the granitic dikes penetrate both diabase and dioryte,
and are clearly younger than the latter rocks. At some lo-
calities they are furthermore distinctly seen to be of more re-
cent age than the quartzitic schists, and the overlying Niaga-
ra and pre-Niagara series. .

The remarkable conformity in strike of the dikes in Casco
bay with that of the enclosing schists renders it probable that
they represent the products of volcanic energy, coincident
with one of the great paleozoic movements of the Atlantic
border region. It is conjectured that this movement occurred
towards the close of the Devonian period, contemporaneously
with the granitic intrusions of Nova Scotia, New Brunswick*
and Vinal Haven,t but a careful geologic study of the entire
Maine coast is necessary before this problem can be definitely
solved.

*See J. W. Dawson: Quart. Journ. Geolog. Soc., Vol. 44, p. 814.
{G. OS Smith=jop, cit.;"p. 75:

Thomsonite and Lintonite from Lake Superior —Winchell. 347

[Contributions to the Mineralogy of Minnesota. II.]

THOMSONITE AND LINTONITE FROM THE NORTH
SHORE OF LAKE SUPERIOR.

By N. H. WINCHELL, Minneapolis, Minn.

Thomsonite. | The megascopic characters of this mineral,
as already stated, are somewhat different from those of meso-
lite. It is not known to possess those peculiar cat’s-eye mark-
ings; its fibres are coarse, and the cavities in which it is found
are large and of irregular branching shapes, as compared with
the round or oval masses of mesolite. It is white and diver-
gently fibrous, and sometimes it is found in the same masses
with mesolite, with which it is intimately interlocked. It
seems to take some part in the recurring bands of color which
constitute the marked characteristic of mesolite.

Its microscopic characters differ from those of mesolite
not.only in the manner already mentioned under mesolite, but
in the spreading and ofter fern-like forms which the fibres
assume, as they radiate and develop from a common point.
This mineral is orthorhombic, and has strictly parallel ex-
tinction. Its optic plane is parallel to the base oo1, and hence
its fibres show sometimes a positive and sometimes a negative
elongation. Its optic angle, which contains 7,. is small, and
hence sections perpendicular to m#, are much darker than
those perpendicular to m,. The double refraction is strong
(0.027 , Lacroix).

It has already been stated that this zeolite is sometimes
intimately mingled with mesolite. This but rarely occurs as
straight, conspicuous, independent fibres of mesolite, piercing
obliquely the thomsonite mass, but has been seen rather to
consist in close, nearly parallel, minute fibres which appear
at certain zones in the recurring colored bands of the meso-
lite. They are distinguished then by their greater light when
they happen to present the axis 7, perpendicular. The axis 7g
is so dark that it cannot be distinguished in the fine mesh, from
the general mesolite mass, but those that happen to be cut
perpendicular to ) appear as bright, short needles, sharp at
both ends, which are quite light compared with the rest of the
section. This is seen in sections of the zeolites from Terrace

point , (535 A).

348 The American Geologist. December, 1898

Localities of Thomsonite. Probably Isle Royale fur-,
nishes this mineral in greater amount than any equal area in
Minnesota. It occurs at the Island Mine, at Chippewa Har-
bor, at Scovill’s point and at two miles SW from Locke’s
point, on the north side of the island. On the north shore of
the lake, in Minnesota, it has been detected at Terrace point
(near Grand Marais), at Fall river where it can be seen to be
a product of alteration of labradorite (200 A), at Poplar river
and eastward, east of Pork bay (163 A) and at Beaver bay.
At the last point it forms the chief constituent in veins in the
anorthosyte masses at the west point of the bay. It occurs
in the rock of Encampment island.

Lintonite. Associated with mesolite and thomsonite at
Terrace point are occasional light green, apparently amor-
phous, small round pebbles, usually found in best form in the
debris of the beach. These are also in the rock that contains
the mesolite masses, and often the two can be seen in the same
cavity. Indeed they are very intimately associated, and the
green color of some of the most prized pebbles is due to this
substance. It forms bands of color, and it fills triangular areas
between the radiated forms of the spherulites when several
spherulites are crowded together in one mass. It has a green
glassy translucency, and its hardness is about that of mesolite.
This mineral was analyzed by Miss Laura Linton and re-
ported by Peckham & Hall with the following result. (1).
Analysis (2) is by F. L. Sperry.

SIO gee ee er AOD deren Aen ee 44.53
Jel O PAS crea QOS2 Ue ee eee tee 27.36
C20 te 10.37 9.90
Nag Os aes eee AN Oe eee ene RL ae Sa sre 5.92
Ki Oe ee es eee OM Ore ess: MeOs2 0.26
ER Oe 13.75 3.08
He O) Ese eh ipecenrs 0.40

99.89 1OI.05

It was considered by them as a form of the same mineral
(mesolite) and was classed by Dana with thomsonite, to which
all of these Terrace point zeolites were referred.

Thomsonite and Lintonite from Lake Superior—Winchell. 349

Although on chemical grounds this mineral is referable
to mesolite, or to thomsonite, it differs from both in optical
characters.

Its axial plane is not perpendicular to the elongation.
Its acute bisectrix is mg, and the acute optic angle is
very small. Its elongation is negative, 1. e. parallel with 7).
Its refraction is less than that of thomsonite, and its double
refraction is nearly that of quartz. Its angle of extinction
varies from 0° to 19°, and its fibres are short and irregular in
form, their width being about one third or one fourth their
length, without rectilinear boundaries. Sp. Gr. 2.372.

For the purpose of making an approximate measure of
the double refraction of this mineral a slide was prepared
on which were ground simultaneously to the same thinness,
four plates of barite, two of scolecite and a pebble of lintonite
(625B) the last being in the center. In the fine massive, almost
granular lintonite the highest color, being that presented by
sections parallel to the axial plane, compared with the color
given by the barite in similar position, shows that the double
refraction of lintonite is about 0.017 to 0.018, that of thomson-
“ite being 0.028. Such comparison is easily made by the use of
the colored “tableau des birefringences” of Michel Levy, con-
tained in the work Mineraux des Roches. A comparison
with scolesite cut in the same position gives the same result.

This mineral has nearly the same optical and physical char-
acters as jacksonite, but in chemical composition and specific
gravity these minerals are quite distinct. The position of the
optical plane parallel to the fibres allies lintonite with jack-
sonite.

Localities of Lintonite. It was found first at Terrace
point. It is found in the same association at Eclipse beach,
where it forms a casing that surrounds the mesolite masses,
the mesolite radiations penetrating it. It is also found on the
north side of Isle Royale.

350 The American Geologist. December, 189%

{European and American Glacial Geology Compared, XI.)

PRIMITIVE MAN IN THE SOMME VALLEY.

By WARREN UPHAM, St. Paul, Minn.

Going north from Paris, we stopped next, on August 16th
and 17th of last year, at Amiens and Abbeville in the Somme
valley, and saw well the physical and geologic features of this
valley along the distance of about fifty miles from Amiens to
its mouth, at the southeast side of the expanse of shallow sea
called the Channel, which separates France and England.
During the past half century this valley of the river Somme
has been more fully studied and discussed by geologists than
Moel Tryfan, Glen Roy, or any other locality that we visited.
Besides the geologic and archzeologic questions here especially
considered, Amiens, the chief city of ancient Picardy, re-
wards the tourist in its magnificent old cathedral, its good
public library, and its museum, rich in remains of the Bronze
age and of ancient Roman and medieval times; and Abbeville,
a smaller but very interesting city, has the church of St. Wol-
fram and the museum of Boucher de Perthes, occupying the
house in which that famous archeologist lived.

At Abbeville and its northwestern suburb, Menchecourt,
about sixteen miles from the river’s mouth, Boucher de Per-
thes first proved by his researches in the valley gravel de-
posits, published in 1847 and later, that man was contem-
poraneous with numerous species of great mammals which
have since become extinct, as the mammoth, woolly rhino-
ceros, and Irish elk, and with others which long ago ceased
to live in France but are still found in far northern and arc-
tic regions, as the reindeer and musk sheep, or in Africa,
as the hippopotamus, hyzena, and lion. These discoveries led
Dr. Rigollot, of Amiens, to search in the similar but higher
eravel excavations close southeast of that city, at St. Acheul,
where he found rudely chipped flint implements and bones
of extinct animals associated together and occurring most
frequently, as at Abbeville, in the basal part of the gravel
and sand deposits. Rigollot published his observations in
1854; and Boucher de Perthes issued the second volume of
his principal work in 1857, and his final third volume in 1864,
four years before his death.

Primitive Man in the Somme Valley —Upham. oa

It is difficult for us, at the present day of increased knowl-
edge, to comprehend the general incredulity, prejudice, and
reluctance, which the evidences of the great antiquity of man-
kind met and overcame. Little attention, indeed, was granted
to these observers until they were visited and their conclu-
sions confirmed by English archzologists and geologists, Fal-
coner and Prestwich in the autumn of 1858, and Evans and
Lyell in 1859. Their writings, with those of Lubbock and
Alfred Tylor, also of England, Gaudry and others in France,
and Dr. Edmund Andrews, of Chicago, all examining the
Somme gravels, loesslike loam, and peat, during the decade
of 1858 to 1867, established beyond question a human anti-
quity far earlier than the beginnings of written history and
contemporaneous with great climatic and geographical
changes in Europe. Only within recent years, however, since
the origin of the glacial drift through the agency of land ice-
sheets, and the late termination of the Glacial period, no
more than 10,000 to 5,000 years ago, have come to be gen-
erally recognized, are we enabled with confidence to correl-
ate that prolonged time of fluctuating glaciation of the north-
ern lands on both sides of the Atlantic with the Palzolithic
period, represented by the Somme gravels, by the similar
implement-bearing deposits of many other valleys in France,
Belgium, and southern Britain, and by the reindeer-hunting
cave-dwellers in those countries.

In this paper, based on my examination of the Somme
valley, the Palzolithic and Glacial periods are shown to have
been nearly coextensive in duration. But a ruder and earlier
stage of stone-working, which is named the Eolithic period,
had preceded the Ice age, as is shown by the yet more prim-
itive and geologically older flint implements found by Har-
rison and Prestwich on the upland plateaus of Kent and ad-
joining counties in southeastern England. Kent lies 50 to
100 miles northwest from the mouth of the Somme, and ap-
parently had a land connection with France in preglacial
times across the present strait of Dover, so that doubtless
Eolithic men had likewise lived in the Somme region during
that Late Pliocene or Early Pleistocene time, long before the
maximum extension of the European ice-sheet. When the
Glacial period was waning, the latest Paleolithic men of

352 The American Geologist. December, 1898

western Europe appear to have there exterminated most of
the species of large mammals already mentioned, through
persistently hunting them for food, so that at last this peo-
ple, destitute of metals, but skillful in making implements of
stone, bone, and horn, and having even a high artistic taste
in carving figures of animals on horn and ivory, became
mainly restricted,.in providing food, to the sea borders, liv-
ing in the greatest numbers in Denmark, and subsisting on
smaller game, fish, and especially littoral marine mollusks,
whose shells form the principal mass of the very remarkable
kjokkenmoddings (kitchen-middens) of the Danish coasts.
About the time of the recession of the ice-sheet from the
Mecklenburg or Baltic moraines, described by the sixth paper
of this series, another race or group of peoples, more advanced
toward civilization, having attained the art of polishing their
stone implements, tending herds and practising agriculture in
some degree, and bringing with them domestic animals and
cultivated plants derived from wild species in the fauna and
flora of western central Asia, immigrated and took possession
of Europe, supplanting and probably mainly exterminating
the old Paleolithic people. This great immigration, ending
the Paleolithic and inaugurating the Neolithic period, was
probably the dispersal of the Aryans, who, as shown by the
researches of philologists, carried throughout Europe lang-
uages of close affinity with those which at the same time or
partly later spread also through Persia and India.

The men of the Somme gravel deposits belonged, if I
rightly interpret the geologic record, to the early part of the
Glacial period, previous to its culmination; the inhabitants of
the caverns of Dordogne, in southwestern France, possessing
greater skill in the manufacture of flint implements and adding
others of bone and horn, hunting herds of wild horses and
reindeer, seem correlative with themaximum stage of glacia-
tion; and later these people spread northward, following the
retreating ice-sheet to the boundary of its Mecklenburgian
stage. De Mortillet and Cartailhac, as archzolgists, divide
the Paleolithic period of France into four epochs or stages,
succeeding one another as follows: 1, Acheulian, named from
St. Acheul (or Chellean, from Chelles near Paris); 2, Mouste-
rian, from Le Moustier in Dordogne; 3, Solutrian, from So-

x

Primitive Man in the Somme V. alley —Upham. 353

lutré in Burgundy; and 4, Magdalenian, from the caves of La
Madeleine in Dordogne. These time divisions are character -
ized by increasing variety and excellence of the implements
made, and by concomitant changes of the fauna. The imple-
ments found in the Somme valley are referable only to the
earliest stage, which had at first a mild and moist climate.
changing afterward to severe cold, with thick ice on the rivers
in winter, broken and floating large blocks of rock in spring.
Let us now examine the geologic origin and deposits of this
valley in their relation to these stages of archeologic develop-
ment, comparing both records with the ascertained history of
the Ice age in the British Isles and northern Europe, and with
estimates of its duration and that of the Postglacial period.

Above Amiens the Somme basin has been eroded to an
undulating surface of broad but low hills and ridges, and is
drained by several streams which converge in and near that
city, being the sources of the supply of the Pleistocene gravels
extensively excavated at St. Acheul, St. Roch and Montiers,
which are situated respectively in the southeastern, western,
and northwestern environs of the city. From Amiens to the
sea the valley is troughlike, with a bottomland from a half mile.
to a mile and a half in width, down to Abbeville, and thence
widening to three or four miles at its mouth, inclosed usually
by very gentle or moderately steep slopes, but in a few places
bordered by a steeper or precipitous bluff formed through di-
rect undermining by the river at some time during the slow
process of the valley erosion.

The river at Amiens is about 65 feet above the mean tide
sea level; at Montiers, 58 feet; and at Abbeville, about 15 feet,
the high tides having formerly reached above the city, until
held back by the engineering improvements of the river course
which now restrict its once meandering and dividing waters
to a single straight canal along its next nine miles. The bot-
tomland is mostly no more than two to five feet, and in its
highest ‘parts about ten feet, above the river in its ordinary
low water stage. Along nearly all the distance below Amiens,
it has large tracts of peat, from 10 to 30feet in depth, thus
extending far beneath the level of the river, or even, in the
vicinity of Abbeville, beneath the sea level. During many
centuries the peat has been excavated for fuel, and many

54 The American Geologist. December, 1898

Or

small ponds, or moats, as they would be called in New Eng-
land, occupy these hollows, and in other places mark aban-
doned parts of the earlier river channel. Since the close of
the Glacial period, the Somme valley has received too little
alluvium to keep pace with the slight epeirogenic depression
which has been in progress; but at the mouth it has been
filled by the coastwise drift of sand from the marine shore
erosion, and by the muddy sediments deposited from inflow-
ing tides.

On each side of the valley the upland extends far away in a
great plainlike expanse, as seen in any wide view, though
everywhere somewhat undulating, with an elevation of 150 to
250 feet above the river and its bottomland. Rounded out-
lines descend to the Somme and to the ramifying tributary
streams, betokening a prolonged period of subaerial denuda-
tion by rains, rills, brooks and the main river, quite unlike
the sharp-crested bluffs eroded, for example, in the glacial
drift along the similarly deep Minnesota river valley and other
valleys cutting thick drift plains in the upper part of the Mis-
sissippi basin. The Somme, lying south of the European
glaciated area, has in its gravel deposits only materials de-
rived from its own drainage basin, which consists of approx-
imately horizontal Cretaceous strata of chalk, with concre-
tionary flint nodules, and here and there overlying remnants
of Eocene sand and clay, locally hardened to sandstone and
shale. Residuary clay or loam, left in the process of denuda-
tion, covers the upland surface to a depth varying generally
from two or three to six or eight feet.

The erosion of the Somme valley to essentially its present
width and depth seems to me attributable to the work of the
river during the very long Miocene and Pliocene periods,
and to have been completed nearly as now before the great
epeirogenic uplift causing the Ice age, which probably raised
the British Isles and northern France at least 1,500 feet to
2,000 feet higher than now, while southwestern France and
the Spanish peninsula appear to have been elevated much
more. The evidences of this very great general uplift of
western Europe were stated in the seventh paper of this
series.* The record of the Glacial period here appears, in

*Am. Geologist, X XII, tor-108, August, 1808.

Primitive Man in the Somme Valley.—Upham. 355

my view, to be almost-wholly represented by deposition of
the gravel and sand on the lower flanks of the valley slopes,
chiefly adjoining the mouths of tributaries;and it is in the
older of these gravel beds that the flint implements occur,
indicating the sojourn of men there at the beginning and
through the early part of the Ice age. |

In referring the valley erosion thus to middle and late
Tertiary times, I agree with Alfred Tylor, whose careful dis-
cussions of this valley and those of southern Britain have
hitherto received less attention than they deserve, probably
because they differ from the earlier published views of Prest-
wich, Lyell, Lubbock, Evans, and others, who ascribe the
excavation of the lower part of the Somme valley to -river
action during the Palzolithic period, while the later gravel
beds were being deposited, or in the intervals of such deposi-
tion and afterward.* The Tertiary erosion extended through

*Without attempting reference to all of the multitude of papers
and books relating to the evidences of primitive man in the Somme
valley, citation of some which are more important or comprehensive
may be noted as follows:

Boucher de Perthes, Antiquités Celtiques et Antédiluviennes,, vol.
I, pp. 628, with 80 plates (1600 figures), 1847; vol. II, pp. 511, with 26
pls. (500 figs.), 1857; vol. III, pp. 681, with 12 pls. (104 figs.), 1864.

Sir Joseph Prestwich, Proc. Roy. Soc., 1859; Phil. Trans., 1860,
1864; many later papers, especially in Quart. Jour. Geol. Soc.; and his
Geology, vol. II, 1888.

Sir Charles Lyell. Brit. Assoc. Report, 1859, Pt. 2, pp. 93-95; The
Geological Evidences of the Antiquity of Man, 1863, chapters VII and
VIII. ;

Sir John Lubbock, numerous papers, 1861-1864; Pre-historic Times,
1865, 1869, chapter XI.

Sir John Evans, Archzeologia, 1862, pp. 28, with four plates;
numerous other papers; and Ancient Stone Implements, Weapons, and
Ornaments, of Great Britain, 1872 (exceedingly useful in its fullness
of bibliographic references).

Prof. W. Boyd Dawkins, numerous papers, 1862 and onward; Cave
Hunting, Researches on the Evidence of Caves respecting the Early
Inhabitants of Europe, 1874.

Alfred Tylor, Quart. Jour. Geol. Soc., vol. X XII, 1866, pp. 463-468:
vol. XXIV, 1868, pp. 103-125, with two plates (map of Amiens and
vicinity, and 13 sections), and 13 figures (sections, profiles, and a map)
in the text [same also in the Am. Jour. of Science, second series, vol.
XLVI, pp. 302-327, with plates, Nov., 1868]; and vol. XXV, 1869,
pp. 57-100, with six plates (abstract and discussion of this paper in
vol. XXIV, pp. 455, 456).

Dr. Edmund Andrews, Am. Jour. Sci., second series, vol. XLV,
pp. 180-190, March, 1868.

Prof. James Geikie. The Great Ice Age and its Relation to the
Antiquity of Man, 1874, 1877, 1894; Prehistoric Europe, 1&88r.

Prof. Gabriel de Mortillet, Matériaux pour |’Histoire Primitive et
Naturelle de l’Homme, 1865 and onward; Le Prehistorique, 1883.

350 The American Geologist. December, 1898

a duration of probably one or two million years, which would
permit the valley to have its origin chiefly by rock solution,
as the deepening of the excavation to 200 or 250 feet would
be at an average rate of no more than an eighth ora third
of an inch for each century.

When the more rainy and snowy climate of the Glacial
period caused larger floods of the streams, especially during
the spring months, the residuary loam and gravel mantling
all the surface were subjected to exceptional denudation.
Considerable material was swept down every stream course
and ravine, until, on debouching into the main valley, the
flood could expand more widely and so lose its velocity and
transporting capacity. The gravel and sand were then de-
posited along the border of the broad bottomland and in al-
luvial fans upon the lower part of the inclosing slopes
wherever tributary streams or the fills of rains and snow-
melting descended. ;

Instead of forming continuous, level-topped terraces, at
successive hights, up to nearly equal vertical limits on each
side of the valley, like the terraces of modified drift on the
Connecticut river along its upper half where it is the boun-
dary between New Hampshire and Vermont, or like the usual-
ly less numerous terraces of this kind in most valleys of
glaciated countries, the Somme gravel and sand are of less
amount and have gentle or steep slopes toward the center
of the valley, presenting a terrace escarpment only where

Emile Cartailhac, Matériaux, 1865 and onward; La France Prehis-
torique, 1880.

Ladriére, Annales de la Société Géologique du Nord, vols.
XVIII-X X (summarized in Geikie’s Great Ice Age, third ed., 18094,
pp. 629-637).

Albert Falsan, La Période Glaciaire étudiée principalement en
France et en Suisse, 1880.

Prof. Daniel Wilson, Prehistoric Man: Researches into the Origin
of Civilisation in the Old and the New World, 1862, 1865, 1876.

James. C. Southall, The Recent Origin of Man, as illustrated by
Geology and the Modern Science of Prehistoric Archeology, 1875.

Prof, Alexander Winchell, Preadamites: or a Demonstration of the
Existence of Men before Adam; together with a Study of their Con-
dition, Antiquity, Racial Affinities, and Progressive Dispersion over
the Earth, 188o.

Prof. G. Frederick Wright, The Ice Age in North America and its
Bearings upon the Antiquity of Man, 1889; Man and the Glacial
Period, 1892.

Prof. Daniel G. Brinton, Races and Peoples: Lectures on the
Science of Ethnography, 1890.

Primitive Man in the Somme Valley —Upham. an7

marginal parts of these deposits have been later carried away
by the undermining action of the streams which brought them
or of the main river. Along the Connecticut river a wide
flood plain of modified drift was built up, filling the valley,
to the level of the highest continuous terraces, 100 to 200
feet above the river; and the terraces are remnants of that
flood-plain and of the lower temporary levels occupied and
abandoned by the river during its process of removal of the
greater part of that original deposit of the modified drift.
Above the highest terraces of the main Connecticut valley,
however, some of its tributaries, exceptionally supplied with
drift from the drainage of the contiguous receding ice-sheet,
formed lateral deposits, terrace plains and alluvial fans, as at
North Haverhill and in other places south to Hanover, N. H..,
ranging in hight from 40 to 250 feet above the valley terraces,
analogous in their mode of deposition with the Somme
gravels.* In the Somme valley the supply of material was less
than that set free from the melting North American ice-sheet,
and it was insufficient to build up a flood-plain in any part
of this valley below Amiens, though at many places it formed
extensive deposits on either side, which sometimes reach, with
slopes nearly like those inclosing the valley, from the bot-
tomland up to hights of 50 to 100 feet; and patches of sim-
ilar gravel and sand occasionally are observable also at greater
hights, nearly to the verge of the uplands.

Levelling done for Mr. Alfred Tylor by the railway en-
gineer, M. Guillom, gave the altitudes of the bottom and the
original surface of the large St. Acheul gravel pits (two are
each a quarter of a mile long), the richest in flint hatchets
among the numerous excavations in and near Amiens, as
respectively 140 and 160 feet above the sea, or about 75 and
95 feet above the river, which is a half mile distant to the
north. The pits are not at the upper limit of the gravels, for
Tylor remarks that “the sections near Amiens show the val-
ley-gravel continuous from a height of 200 feet, at St. Acheul
* *« * to the River Somme (coated over by a nearly uni-
form warp of loess), and laid at a low gradient not exactly
parallel to the surface of the chalk, but rather in its concav-
ities.” These higher gravel beds, however, having no exca-

«Geology of N. H., vol. nee 1878, pp. 29-38, with maps and sections.

358 The American Geologist. December, 1898

vation, it is not known whether they contain stone implements
and fossil bones; but generally, according to Ladriére, these
are absent or rare in the highest beds of the valley gravels
throughout northern France. In the vicinity of Montiers,
one to two miles northwest of Amiens, nine gravel pits, con-
taining worked flints and bones of extinct animals nearly as
at St. Acheul, are shown by Tylor’s description and map to
range in hight from 77 to 155 feet above the sea, or from 17
to 95 feet above the Somme, the upper limit of the excava-
tions being the same in relation to the river as near St. Acheul.
The distinction of upper and lower gravel deposits, which
Prestwich and Lyell made prominent in their writings, was
pronounced by Tylor, as it seems to me with sufficient rea-
sons, to be seldom definitely observable, the series, where
developed at considerable hights, being usually continuous
thence down nearly or quite to the bottomland and river.
Ladriére, who in 1875 and ensuing years has extensively
examined and described the Pleistocene valley deposits of the
Seine, Somme, and other river basins of a wide region ex-
tending northward into Belgium, divides these deposits into
three somewhat similar series, successive in age and stratt-
graphic order, each of which can be traced from the bottoms
of the valleys up to the plateaus, though not to their greatest
hights. These series, each consisting of a regular sequence
of gravel, sand, loam or loess, etc., representing three dis-
tinct stages of the Pleistocene period, are doubtless to be
correlated with stages of advancing glaciation, interrupted by
times of decrease and recession of the European ice-sheet.
The researches of Ladriére thus present a record of climatic
changes south of the glaciated area, by which geologists may
very satisfactorily connect the evidences of primitive man
in France with the time divisions of the Glacial period. His
detailed notes of each of the three Pleistocene series and
stages recognizable in these valleys are fully quoted by
Prof. James Geikie in the third edition of the “Great Ice Age”
(1894, pp. 630-632), from which it appears that flint imple-
ments of the Acheulian or Chellean type occur throughout
the lower series; that such implements are also found in the
middle series, but probably, as Ladriére thinks, through de-
rivation from the older and stratigraphically lower beds; and

Primitive Manin the Somme Valley —Upham. 359

that the infrequent implements found in the upper series are
of the later developed Mousterian type.

We may infer, additionally, that while the still later So-
lutrian and Magdalenian types of implements were being de-
veloped, in the progress of the Palzeolithic period, more mod-
erate climatic conditions prevailed in northern France, with
no important contribution to the valley gravels. These three-
fold deposits therefore appear referable to early stages of the
Ice age, probably the Albertan, Kansan, and I]linoian, or
rather to the European representatives of these stages. Dur-
ing the very long interval that ensued, previous to the Iowan
or Polandian readvance of glaciation, the Paleolithic men
of western Europe passed through their Solutrian and Mag-
dalenian stages; and shortly afterward, about the time of for-
mation of the Wisconsin or Mecklenburg moraines, these
men, destitute of metals, of agriculture, or of domestic ani-
mals, were practically crowded off from Europe, famished by
extinction of the large species of game, and driven out, ex-
terminated, or absorbed, by the immigrating. Neolithic peo-
ple. The invaders, as before noticed, though ignorant of the
most useful metals, brought wheat and barley, cattle, sheep,
goats, and swine, and, most significant in linking them with
later written history, the Indo-European languages. Their
arrival and settlement, and the end of the Paleolithic period,
preceded the departure of the ice-sheet from Scotland and
Scandinavia, where no Paleolithic types of stone implements
are found, although Neolithic types abound and are collected
in immense numbers.

Sections of the Somme gravels at Menchecourt, Mautort,
and other localities near and below Abbeville carry back the
Acheulian stage of Paleolithic time quite to the beginning
of the Ice age. The many other sections in this valley dis-
play ice-floated sandstone blocks and deformations of the
strata attributable to the melting of masses of river ice; but
these disturbed conditions were absent when human imple-
ments and the bones of the mammoth, the woolly rhinoceros,
wild horse, urus, stag, reindeer, lion, and hyzna, were mingled
in the Menchecourt gravel and sand beds, which are about 20
to 30 feet above the sea level, under subsequent deposits of 20
feet of loam and clay, the surface being about 50 feet above

360 The American Geologist. December, 1898

the sea or 40 feet above the river. The sections of Menche-
court, Mautort, etc., are further distinguished from others at
higher levels near Abbeville, and from all at both low and
high levels along the upper part of the valley, by their con-
taining marine shells. Lyell writes of their mode of occur-
rence at Menchecourt as follows:

In the lowest beds of gravel and sand in contact with the chalk,
flint hatchets, some perfect, others much rolled, have been found; and
in a sandy bed in this position some workmen, whom I employed to
sink a pit, found four flint knives. Above this sand occur beds of
white and siliceous sand, containing shells of the genera Planorbis,
Limnea, Paludina, Valvata, Cyclas, Cyrena, Helix, and others, all
now natives.of the same part of France, except Cyrena [Corbicula]
fluminalis, which no longer lives in Europe, but inhabits the Nile and
many parts of Asia, including Cashmere, where it abounds. No species
of Cyrena is now met with in a living state in Europe. Mr. Prestwich
first observed it fossil at Menchecourt, and it has since been found
in two or three contiguous sand-pits, always in the fluvio-marine bed.

The following marine shells occur mixed with the fresh-water
species above enumerated: Buccinum wundatum, Littorina littorea,
Nassa reticulata, Purpura lapillus, Tellina solidula, Cardium edule,
and fragments of some others. Several of these I have myself col-
lected entire, though in a state of great decomposition. . . . They
are all littoral species now proper to the contiguous coast of France.
Their occurrence in a fossil state associated with fresh-water shells
at Menchecourt had been noticed as long ago as 1836 by MM. Ravin
and Baillon, before M. Boucher de Perthes commenced the researches
which have since made the locality so celebrated. The numbers since
collected preclude ali idea of their having been brought inland as
eatable shells by the fabricators of the flint hatchets found at the bot-
tom of the fluvio-marine sands.

This part of western Europe was then slightly lower than
now, indicating, with the absence of ice before noted, that
the time represented by these sections preceded the great
uplift of this region which culminated in the maximum Eur-
opean glaciation. But earlier, and probably continuing with
increased vertical and geographic extent during the early part
of the Ice age, the general epeirogenic uplift of the continental
area bridged the strait of Gibraltar and the center of the Med-
iterranean sea from Tunis to Sicily and Italy, as shown by
Dawkins and Geikie, raising the land in both regions about
2,000 feet higher than now, and affording a passage to the
great African mammals. They also crossed where the shal-

Primitive Man in the Somme Valley —Upham. 301

low strait of Dover now is, entering Britain;and during the
oncoming and culmination of the Ice age the British Isles
were united with the continent by a very broad land surface,
reaching far west of the Channel and occupying the basin of
the North sea and nearly all the area between Scotland and
Norway, until the Scandinavian ice-sheet covered that land
plain to northeastern England.

Our estimates of the duration of the Postglacial period are
based on computations by Andrews from the shore erosion
and beach sand accumulation of lake Michigan; on his inves-
tigation, before cited, of the age of the peat beds in the Somme
valley and of the alluvial fan deposits of the Tinieére, tributary
to lake Geneva, which latter had been differently interpreted
by. Morlot; on the study of the recession of the falls of St.
Anthony by Prof. N. H. Winchell; on that of Niagara falls
by Gilbert and others; on Dr. Robert Bell’s observations of
the extent of subaérial erosion of limestone rocks in Canada;
and on many other careful studies in both North America
and Europe. These estimates concur so well that the dur-
ation which they give approximately as between 5,000 and
10,000 years may be confidently accepted as the measure of
Postglacial time. It may be otherwise and better stated that
the departure of the ice-sheets on these continents probably
occupied some 5,000 years, known as the Champlain epoch
from marine deposits overlying the glacial drift in the basin of
lake Champlain; and that it was completed, nearly as now,
about 5,000 years ago, with remnants of the old ice-sheets lin-
gering ever since in Alaska and Greenland and on the moun-
tainous plateaus of Norway. The incursion of the Neolithic
men and doom of their Paleolithic predecessors belong thus
probably 6,000 or 7,000 years ago.

The duration of the Ice age cannot be so reliably deter-
mined; but the researches of Geikie, Chamberlin, and many
others, convince us that on both sides of the North Atlantic
glaciation was approximately synchronous, with parallelism in
its beginning, fluctuations, and end, through a period ten to
twenty times as long as that which has followed it, or of some-
what such ratio. In other words, the Glacial period, from the
time of the Paleolithic men at Menchecourt and St. Acheul
to the Neolithic immigration and the not widely later re-

362 The American Geologist. December, 1898

treat of the ice-sheet in Scotland, Sweden and Norway,
measured probably 50,000 or 100,000 years.

It is therefore right that the Acheulian men should be
termed primitive. They had not learned how to use the
Creator’s gifts. The power of invention, ready to bestow do-
minion and utilization of animate and inanimate nature, lay
dormant and was scarcely beginning to awaken; but even then
the men in the Somme valley were doubtless mentally and
physically developed far nearer to otirselves than to the mist-
covered morning and dim dawn of the earliest human diver-
gence from an ancestral anthropoid species perhaps ten or
twenty times more ancient.

On leaving Abbeville, our journey continued through
Boulogne, Calais, Dover, and Canterbury, to London. Again
in that great city, a few days were spent in its libraries, muse-
ums, parks, and in excursions to the outlying country. Then
we embarked at Southampton, eighty days after out landing
there; arrived in New York on August 27th; and, after visit-
ing eastern friends, reached home in St. Paul on September
oth, bringing memories, experience, and note-books of the
summer of 1897, long planned for and happily completed.

THE GREAT TERRACE OF THE COLUMBIA
AND OTHER TOPOGRAPHIC FEATURES
IN THE NEIGHBORHOOD OF LAKE
CHELAN, WASHINGTON.

By IsrRAEL C. RussELL, Ann Arbor, Michigan.

In an article by Mr. William L. Dawson, on “Glacial
phenomena in Okanogan county, Washington,” published in
the October number of this journal, exceptions are taken to
my measurement of the hight of the great terrace of the upper
Columbia, and to certain conclusions based on my recon-
noissance in central Washington in 1892. Having made a
second journey through the Lake Chelan region during the
past summer and obtained additional data in reference to its
surface geology, I feel that I am qualified to reply to Mr.
Dawson’s criticisms, and to offer in return a few suggestions
in reference to his interpretations of the history of some of

The Great Terrace of the Columbia.—kussell. 363

the more striking features in the topography of that most in-
teresting country.

The Great Terrace of the Columbia. In my report of
1892* the great gravel terrace, bordering the Columbia in
the neighborhood of lake Chelan and occurring at many
localities further up the Columbia, was briefly described and
the elevation of its surface above the river stated to be 700
feet. This is an aneroid measurement, or rather the mean of
several such measurements, and I believed, at the time, was
as accurate as the method employed could be expected to
yield, especially when opportunities for rating the barometer
could be had only at wide intervals. Mr. Dawson states
positively thatthe great terrace is but 300 feet above the
Columbia; whether this is an aneroid measurement or the
result of some more accurate method is not recorded.

During the past field season I again examined the great
terrace referred to, at various localities from the mouth of
the Methow southward along the Columbia, to where it
terminates a few miles south of the mouth of Chelan river.
The terrace is especially well displayed at the mouth of the
Methow, where it forms a plateau fully a mile-and-a-half
broad. I again measured its hight, using an aneroid in which
I had learned to place much confidence. This measurement
was in duplicate, one set made on descending from the
surface of the terrace to the river and the other on returning;
the reading on the return was the same as at the start. These
observations gave 550 to 560 feet as the hight of the surface
of the terrace above the river. On the uplands bordering the
great terrace, at the locality just referred to, there are other
terraces about 100 feet higher, but these belong in another
category and have a different history than the great terrace.
The surface of the great terrace is in several places quite ir-
regular, on account of the settling of the material composing
it so as to form basins, but in general slopes gently from the
bordering uplands to the broken escarpment overlooking the
river. This difference where the terrace is broad amounts to
fully too feet. Another measurement of the hight of the great
terrace, at a locality about five miles south of the mouth of

*Bulletin No. 108, U. S. Geological Survey.

304 The American Geologist. December, 1895

the Methow, gave an elevation of 570 feet. Still other aneroid
readings on the great terrace farther down the Columbia,
without, however, descending to the river, but referring back
to the reading obtained at the mouth of the Methow two days
previous, gave an elevation of 660 feet. This discrepancy of
about 100 feet, I believe to be due mainly to changes in atmos-
pheric conditions.

The great terrace referred to above is, without question, a
portion of the same terrace visited by me in 1892, below the
mouth of Chelan river and on the left bank of the Columbia.
As previously stated, the hight above the river there obtained
by aneroid, was 700 feet. This measure is probably some-
what too high, judging by the observations made by me this
year, and may perhaps be 100 feet in error, but as. the hight
of the terrace above the river probably increases somewhat
as one follows it down stream, I doubt if the probable error
is as much as just stated. Mr. Dawson assigns an elevation of
but 300 feet for the great terrace above the river, and the dif-
ference between our determinations is from 250 to 400 feet.
This wide discrepancy is the more surprising as the difference
between the elevation of the Columbia at the mouth of
Chelan river, and the surface of lake Chelan, as determined
by Mr. Dawson, and by myself in 1892, is the same, namely
205 eet.

In volume one, of the reports frequently termed the
“Pacific Railroad Surveys,” there is a paper of Professor
George Gibbs, in which the Terrace in question is referred
to as follows, (page 483):

“On leaving the Columbia to visit the Chelan lake, our
route ascended one of these terraces, rising to a height of
six hundred and forty feet in a single slope, and occupying
a recess in the hills which bordered it. On reaching the top,
it proved to. be the entrance of a level valley, extending
through the hills and emerging about one hundred and fifty
feet above the lake.”

As correctly stated by Mr. Dawson, the great terrace of
the Columbia is. a true stream terrace. It is one of a large

*Recent measurements with engineer levels, made by the Topo-
graphic Division of the U. S. Geological Survey, show that the surface
of lake Chelan is 1078 feet,and the mouth of Chelan river 670 feet above
the sea; the difference is 408 feet.

The Great Terrace of the Columbia.—Russell. 365

series of similar terraces which occur along many of the rivers
of eastern Washington. There is a similar great gravel
terrace in the canyon of Snake river, another along Spokane
river, and other in the valleys of the Okanogan, Methow,
Yakima, etc. These several terraces have many features in
common, but as they have not been adequately studied, more
information concerning them is necessary before their histories
can be interpreted with confidence. All the streams referred
to, however, flow to the Columbia and converge toward the
depressed region in east-central Washington. In all cases
thus far observed, also, the terraces are conspicuous on the
upper course of the rivers where their valleys or canyons are
narrow, and disappear lower down the river where their
valleys become broad. For example, on following the
Columbia southward from the mouth of Chelan river, the
valley soon broadens and one looks in vain for the great
gravel terrace so conspicuous farther up stream. This,
termination of the great terrace of the Columbia when traced
down stream is one of the reasons for believing in the former
existence of a lake in the basin-like portion of south-central
Washington. This water body was named lake Lewis by
Symons, but full and unquestionable evidence of its actual
existence can not be said to have been discovered. With
lake Lewis filling the valley of the Columbia below where
the great terrace terminates, we are enabled to give a natural
interpretation of the great gravel deposit in the valley of the
upper Columbia. That is, the Columbia discharged into lake
Lewis, and built a delta of coarse material, being, as I am in-
clined to believe, overloaded with debris like many other
rivers in the same general region, on account of the changes
in conditions accompanying the Glacial epoch. With the
building of the delta the river channel, up stream from it, be-
came deeply filled with gravel, and after the waters of lake
Lewis were withdrawn, the Columbia excavated its present
inner channel through the gravel, partially filling its old rock-
cut valley.

This is in outline my interpretation of the history of the
ereat terrace of the Columbia, but as only a portion of the
field has been studied and this in connection with recon-
noissance work, I hold my conclusions lightly and am willing
to change them if additional observations demand it.

366 The American Geologist. December, 189%

The Methow Glacier. In the article by Mr. Dawson, re-
ferred to above, it is stated that formerly three glaciers flowed
eastward from the Cascade mountains and reached the
Columbia; these ice streams “swept down the Chelan, Methow
and Okanogan valleys, respectively.” The evidence in refer-
ence to the Chelan and Okanogan glaciers, as is well known,
fully confirms a portion of this statement, but, as to the
Methow glacier, | wish to say that I followed the Methow
river during my reconnoissance of last summer, from near its
source at the crest of the Cascade mountains to its junction
with the Columbia, and found abundant evidence of the
former presence of glacial ice from the source of the river to
Winthrup. At Winthrup the river receives an important
tributary from the north, and its valley broadens. The
former glacier expanded in this broader portion of the valley
and reached some four or five miles south of Winthrup and
deposited a fine group of kames with undrained basins be-
tween, some of which still hold lakelets. From the locality
just mentioned to the mouth of the river I failed to find any
evidence of the former presence of a glacier. The Methow
glacier according to my observations did not reach within
about 40 or 50 miles of the Columbia, and hence cannot be
appealed to as having any connection with the origin of the
coulée crossing the promontory on the east bank of the
Columbia, opposite the mouth of the Methow. I refer to the
so called “glacial channel” shown on Dawson’s instructive
diagram forming figure one, page 206, in the article under re-
view. According to the explanation advanced by Mr. Daw-
son, the Methow glacier dammed the Columbia, and caused
the river to rise “to a hight sufficient to enable it to cut across
the corner, where it excavated a deep transverse channel
some 150 feet down into the granite.” The transverse channel
referred to attracted my attention last summer, while on the
opposite or west side of the river, but I did not visit it. Some
of its features, however, may be better studied from a distance
than by close inspection, as I believe will be shown by my
interpretation of it made in the field. I therefore transcribe
the following passage from my note book: ‘The great
terrace occurs on each side of the Columbia and extends far
up its course above the mouth of the Methow. Just opposite

The Great Terrace of the Columbia —Russell. 367

where the Methow comes in there is a bold rocky promontory,
on the plateau-like surface of which there are a few crags ris-
ing above the level of the great terrace. This rock mass is
separated from the mountains to the east by a coulée through
which the Columbia or a part of its waters once flowed. The
bottom of the coulée is below the level of the great terrace.”
The explanation of the origin of the coulée which presented
itself to me, from the facts as I saw them, is, that the river
when its channel was occupied from side to side by the gravel
deposit now represented by the great terrace, was greatly ex-
panded, being a broad, swift stream, and that a portion of its
current followed the now abandoned coulée, leaving the crags
on the surface of the mesa at the summit of the promontory,
as islands. Later, when the Columbia re-excavated its chan-
nel, the branching passage in solid rock was abandoned. The
river did not make the coulée, but simply modified its bottom
to some extent. The origin of the coulée need not be dis-
cussed at this time but the fact that it is older than the great
terrace is beyond doubt. This explanation meets all of the
conditions as I saw them, and is in harmony with the histories
of other coulées, similar to the one described above, and be-
sides is independent of the Methow glacier, which according
to my observation did not come within at least forty miles
of the region under discussion.

Antwine’s Coulée: On the west side of the Columbia
valley and south of the mouth of the Methow, there is a deep,
narrow channel, similar in character to the one referred to
above, but of much larger size, known as Antwine’s coulée.
As correctly stated by Dawson, Antwine’s coulée connects the
Methow valley at a locality about four miles above its mouth
with the’ Columbia valley, some ten miles to the south. This
deep, narrow defile is described by the author cited above as
a glaciated channel, “which the ice has hollowed out between
some sturdy outlying spur and its parent mountain.”

I traversed the entire length of Antwine’s coulée last
September, but failed to find any evidence to suggest that it
had once been occupied by a glacier. The narrow, steep

sided trench is crossed from side to side by alluvial cones, and
talus slopes, between which there are several undrained basins,
three of which hold lakelets. The coulée is also obstructed by

368 Lhe American Geologist. December, 1898

blocks of rock which have fallen from the bordering cliffs,
but is entirely without glacial scorings, moraines or other
evidence of ice work.

Below or south of the southern end of Antwine’s coulée,
as also stated by Dawson, there is another short coulée,
similar in character to those just considered, the course of
which in general,is parallel with the Columbia. The author
just referred to, states that this coulée is about a mile in length
and occupied at present by glacial debris. My study of the
coulée in question, however, failed to show that it contained
any glacial debris or that it was either produced or modified
by glacial action. I did find alluvial cones, talus slopes, fallen
blocks, etc., of the same character as those obstructing Ant-
wine’s coulée.

Knapp’s Coulée: On the south side of lake Chelan, about
three miles from its eastern end, there is another coulée,
similar to those referred to above, known as Knapp’s coulée.
This is a deep narrow trench in a mountain mass that rises
from 1800 to 2500 feet above the lake’s surface, and has a
length of four or five miles. Its general course is nearly at
right angles to the trend of the eastern portion of Chelan
valley, and at its southern end it opens out into the valley of
the Columbia. In describing this channel and discussing its
origin, Mr. Dawson states that: “It is an ice-hewn valley,
a discharge pipe of the Chelan glacier. Originally consist-
ing of two opposite valleys heading at near the same point on
the divide, it was selected by the ice as presenting the easiest
avenue of escape across the rampart; i. e., the lowest point,
and was subsequently deeply excavated by the long continued
and gradually concentrated ice-flow. To-day its superficial
features of kettle-holes and morainic banks have not been
obliterated or even noticeably modified by subsequent
changes.”

I traversed the entire length of Knapp’s coulée last
September, and, as in the similar instances cited above, failed
to find any evidence of the work of ice; but I did find alluvial
cones, talus slopes, and fallen blocks in abundance, together
with undrained basins between the larger obstructions.

The relation of Knapp’s coulée to the valley occupied by
lake Chelan is in itself sufficient to show that the great Chelan

The Great Terrace of the Columbia —Russell. 309

glacier could not have divided so as to send a branching ice-
distributary through it. The conditions as they existed at the
northern end of the coulée during the maximum extension of
the Chelan glacier, are paralleled, I think, in every essential
particular at the present day, on the east border of Hayden
glacier, near Yakutat bay, Alaska. At the locality referred
to, a deep, narrow, transverse channel, a remnant of an ancient
stream channel, cuts across a mountain spur. This channel is
at right angles to the east border of the Hayden glacier, which
forms a wall of ice from 150 to 200 feet high across its upper
extremity but does not extend into it. A small stream, fed
by the melting ice, courses down the lateral channel, but this
is all the direct influence that the glacier has upon it. The
Chelan glacier rose about 200 feet above the lowest point in
the entrance to Knapp’s coulée, but did not enter it. The
melting of the ice very likely fed a small stream which found
its way southward down the coulée, but of this I have no good
evidence.

There are several other portions of Mr. Dawson’s inter-
pretation of the topographical history of the region drained
by the Columbia, which differ widely from the conclusions
based on my own observations, but it does not seem as if
farther discussion at this time would be profitable. It is to be
remembered that no detailed geological studies have been
carried on in the portion of the country under consideration,
at least my own work there is entirely of the nature of a
reconnoissance, and the radical differences between Mr. Daw-
son’s conclusions and my own, can, apparently, only be ad-
justed after more extended field-study.

WwW
a |
oO

The American Geologist. December, 1898

THE OCCURRENCE OF CRETACEOUS FOSSILS IN
THE EOCENE OF MARYLAND.

By Rurus MATHER BAGG, JR., PH. D., Colorado Springs, Col.

Two Cretaceous fossils, Terebratula harlani and Gryphza
vesicularis, were discovered last summer in the Eocene green-
sand while the writer was engaged in survey work for the
State of Maryland. These forms, abundantly and character-
istically developed in New Jersey, have been supposed to be-
long exclusively to the Cretaceous and so far as I am able to
learn there is no record of their occurrence in post-Creta -
ceous deposits,if we except the doubtful report of the presence
of Terebratula harlani in the Tertiary of South Carolina.

One of these fossils, Terebratula harlani, is in New Jersey
confined to a narrow but definite zone of the Rancocas forma-
tion (Middle Marl bed) which averages only two feet in thick-
ness and extends in a northeast-southwest direction across the
entire state. The other, Gryphza vesicularis, while found in
all portions of the Monmouth formation, is, in the Ranocoas,
limited to another definite zone beneath that of Terebratula
harlani.

The specimens of Terebratula harlani which the author
discovered in Maryland were found in the Eocene marl of
Prince George’s county in a bank by the roadside on Western
branch of the Patuxent river about three miles west of Lee-
land, a small station on the Popes Creek railroad. The green-
sand at this cutting in the road is very fossiliferous and carries
the common lower Eocene fauna, Ostrea compressirostra Say,
Cucullaea gigantea ‘Conrad, Cytherea ovata Rogers, and
several others.

The Terebratule under discussion occur in the lower por-
tion of the bank about eight feet above the bend of the road.
They seem to have a limited vertical range of about five feet
and are often grouped together in indurated lenses of the
marl but they are by no means confined to these indurations.
The shells are remarkably well-preserved, very large and
thick, and many of them attain a maximum size for the
species of two and three-quarters inches in width by three
inches in length. These forms so closely resemble New Jersey

Cretaceous Fossils in Eocene of Marylana.—Bbagg. 371

specimens that they could not be distinguished from them if
both were in the same tray. The Cretaceous marls which
underlie the Eocene are at this locality on Western branch
fully twenty feet below this level. Furthermore as these
brachiopoda occur with such characteristic Eocene fossils
as Ostrea compressirostra and Cucullza gigantea there can be
no question of the age of the deposit under consideration.

The second discovery was made in the bluffs of the Poto-
mac river not far from Clifton beach on the Maryland shore
where a perfect specimen of Gryphzea vesicularis showing
both valves was obtained. The shell is identical with those
so numerous in the Rancocas marl bed of New Jersey. An
examination of these Cretaceous fossils shows that their in-
habitants lived in the waters at the time the Eocene green-
sand was being deposited for none of the shells are water-
worn in the slightest degree and the interior of the shell is
filled with the same glauconite and sand grains of which the
surrounding greensand is composed. In fact I not only be-
lieve that these organisms lived side by side with their Eocene
associates but that they existed under most favorable con-
ditions as their large size and thick shells attest.

A key to the explanation of their occurrence is, I think,
to be found in the peculiar relation to the Terebratula and
Gryphza zones as they are developed in the state of Delaware.
On the south bank of the Noxontown mill-pond their position
is well seen. Throughout New Jersey these fossils occupy a
constant position beneath the limesands of the Rancocas.

A generalized section of the New Jersey Rancocas is as fol-
lows:

Thickness in Feet. Formation. Name.
MO=2ZOw ld creme es, Limestone and Limesand.. Vincentown Limesand.
Be SWEPRe <aaxs: rests Terebratula harlani / Shell layers } sevall
Beers tee = ahetae y « Gryphaea vesicularis ) of Cook, ( renee
eG His see ae > OOM es UAT cis ae, 8 ata ¢

After crossing the Delaware river, although these beds
continue southward, their position changes and we find the
shell layers above the limesand. This is well seen along a
large portion of the south shore of Noxontown mill-pond.
If these limesands belong to the same period of deposition as

372 The American Geologist. December, 1898

in New Jersey, and there is no doubt but that they do, then
we must conclude that the Terebratule and Gryphez mi-
grated southward as conditions became unfavorable for their
existence in New Jersey and continued to survive in later time
in Delaware. The development, however, of both the lime-
sand and the shell-layers becomes diminished farther south
and before reaching the Chesapeake bay become so greatly
reduced that the beds are only occasionally observed and it is
doubtful if they exist at all in portions of the belt. The shell-
layers do occur on a branch of the Sassafras river called Swan
creek on Mr. Jacob’s farm. Upon the west shore of Chesa-
peake bay only one locality has heretofore been known where
the Terebratule occur and this was mentioned by professor
P. R. Uhler many years ago. The spot where professor Uhler
discovered this brachiopod was at the base of the oxidized
greensand bluffs opposite Annapolis. In place of the limesand
and the shell-layers we find that the Rancocas formation in
Maryland consists largely of glauconite grains and finely tri-
turated sands which are more highly oxidized than the sands
of the same formation in New Jersey. Furthermore, the glau-
conite is not so abundant, and in Maryland this bed has been
dug for fertilizer in only a few places.

The writer’s discovery of these fossils in Prince George’s
and Charles counties proves that these organisms not only
continued their existence in the Eocene but that they mi-
grated much farther southwest than has previously been sup-
posed. Brachiopoda are rare in the Eocene of the Atlantic
Slope and have never been recorded as occurring in Mary-
land. Even in New Jersey Cretaceous where such a wealth of
mollusca exists only two species of brachiopoda are at all plen-
tiful. These forms are the one under discussion and Tere-
bratella plicata Say. The latter is a small form and occurs
widely distributed throughout the Monmouth formation, be-
ing present in the Navesink marl bed and the Redbank sands.
Terebratula harlani is, on the other hand, one of the largest
and most beautiful of the genus found in America. Prof. R.
P. Whitfield in his monograph of the Cretaceous Mollusca
of New Jersey states that the shell has been obtained from

Cretaceous Fossils in Eocene of Maryland—bagg. 373

South Carolina where it is said to be found in the Tertiary,
but he then adds: ‘This I think extremely doubtful as it is
never found above the Middle Marl beds of New Jersey.”

We cannot suppose that this species of brachiopod, so
abundant in a zone of the Rancocas marl bed disappeared at
the close of this stage and reappeared again in the Eocene.
Nicholson in his Manual says: “There is no record of the
reappearance of any fossil after it has once disappeared.
There are plenty of cases in which a species seemingly dis-
appears in a particular set of rocks to reappear in some higher
and later set of rocks in the same region, whilst its remains
are wanting in all the intermediate deposits of the area. It
also often occurs that the species, having disappeared in one
region, is found in deposits of later age in another area.”
We may therefore infer that if the organism is lacking in in-
termediate deposits either the forms migrated to another
region at that particular period or else the conditions were not
favorable for their preservation.

The study of the migration of organisms which in the past
have inhabited the earth has never been adequately worked
out save in a few instances, but such a study would prove ex-
tremely interesting and profitable. That such migrations did
occur and on a wide scale is strikingly shown by such brach-
iopods as Productus semireticulatus and Streptorhynchus
crenestria, which occur in the lower Cambrian rocks of Eur-
ope, Australia, India, China and North America.

In other words, these forms under consideration must have
migrated from place to place unless we suppose that they had
a universal distribution in a universal ocean, a condition
hardly probable. Inasmuch as sessile forms cannot migrate
and because brachiopoda in adult life are attached, the mi-
eration of this group must have occurred when the forms
were in their larval stage during which they possess the power
of rapid locomotion. Any geological barrier might, however,
have prevented a migration even of free-swimming forms into
closely adjoining areas suitable for their existence. A cold
current of water might act as such a barrier. We must also
bear in mind that not all synchronous deposits disclose the

374 The American’ Geologist. December, 1898

same fauna and the difference becomes more marked if one
deposit is marine and the other terrestrial.

The Cretaceous period in Europe was followed by eleva-
tion over wide regions, but because the elevation was gradual
organisms were often able to migrate; but according to our
present knowledge this place of transference is unknown. On
the Atlantic slope, however, deposition went on over a grad-
ually sinking area of the sea floor and the Eocene marls were
laid down conformably on the underlying Cretaceous. In
reference to this professor Dana in his revised Manual says
(p. 821): “The upper Greensand group graduates without a
break in the stratification into the overlying Eocene Tertiary
as if its formation were like the upper Laramie, the closing
work of the Cretaceous period.”

It is quite possible that a cold current from the north may
have swept along the Atlantic border at the close of the Cre-
taceous and either exterminated the mollusca or else driven it
farther south though I am not certain that we have any proof
of this. It is evident that professor Dana believed in this cold
current acting as a barrier for on page 877 of his revised
Manual he states: “If the change had made the arctic waters
only 15° F. colder than they were during the Cretaceous per-
iod, the polar waters as they flowed southward, would proba-.
bly have been exterminating to the greater part of the life of
coast regions all along the shallower waters, and down to such
depths as the cold current reached. Such a cause might make
a complete break in the succession of species in a region, with-
out any break in the succession of beds, as happened in New
Jersey.”

The writer believes that elevation of the coast line along
the western border of the New Jersey Cretaceous early in Eo-
cene time and a deepéning of the waters farther south was
one of the chief causes for this destruction of life although
it is quite probable that cold currents coming southward may
have completed this destruction. A study of the Eocene de-
posits of Maryland reveals the fact that the formation in-
creases in thickness toward the southwest like a letter V turned
sideways. The apex of the V was near the western

Review of Recent Geological Literature. 375

corner of Noxontown mill-pond in Delaware while the
other end reached the shore of the Potomac river near the
mouth of Potomac creek.

While the upper and lower portions of the Eocene differ
in the character of their fauna and in lithological composition
sufficient to separate the formation into two divisions there
is no doubt but that deposition went on continuously through-
out the entire Eocene period and the increasing thickness
southward is doubtless to be accounted for by supposing that
the Cretaceous shore-line was more nearly stationary in cen-
tral Delaware while the region farther south was undergoing
more rapid and prolonged subsidence. In this way it was
possible for the young of Terebratula harlani and of Gryphza
vesicularis to migrate southward and, passing beyond the Cre-
taceous limit, to continue its existence in the warm and deeper
waters of southern Maryland. Whether the few feet of Eo-
cene marl in New Jersey represents the entire period or not
we cannot say, but inasmuch as there is a line of non-deposi-
tion in Delaware where the Miocene rests directly on the
Cretaceous this line was either stationary or elevated
while deposition was going on both to the north and to the
south of this area. If this is not the case then there was a
period of erosion in some stage of the Eocene, for the Miocene
rests uniformly along the entire region from Shark river in
New Jersey to southern Maryland. It is possible that more
detailed study of the region of central Delaware will yield ad-
ditional facts, though the author of this paper has made a
pretty careful examination of all the available exposures in
that state.

Poe vy OP RECENT GEOLOGICAL

EEA TURE.
Maryland Geological Survey, Vol. 1, 1897. Wm. BuLtuock CrarkK,

State Geologist. The Johns Hopkins Press, Baltimore, Md.

The first report issued by the Maryland Geological Survey is of a
preliminary character and the subjects treated are largely historical
and introductory. Part I. discusses the establishment, plan of opera-

376 The American Geologist. December, 1898

tion and purposes of the survey. These last are a model of what a
geological survey should propose to accomplish for the state which
supports it. The suggestion of the publication of an elementary
treatise, adapted to the purposes of public instruction is in line with
the demands of the new geography. Acting upon this suggestion,
Maryland could enable her youth, without added expense to the state,
to reap the benefits of her peculiarly instructive physiographic and
geologic conditions.

Part II. contains a historical account of all previous investigation
of the physical features and natural resources of the state. This ac-
count includes an interesting sketch of the information acquired dur-
ing colonial days of the physical features of Maryland.

More or less desultory investigation has been carried on since that
time by individual scientists, among whom may be mentioned Lyell.
Official investigation began under the auspices of the First Maryland
Survey (1834-1841) and was continued by the State Agricultural
Chemists (1848-1862), the Maryland Academy of Science (1855), the
Maryland Agricultural College (1856) and Experiment Station (1887),
and finally by the Geological Department of the Johns Hopkins Uni-
versity. With Dr. George H. Williams’ connection with that insti-
tution (1883) began the period of most thorough and productive study
of the geology of the state. The investigation thus inaugurated has
been continued by Dr. Williams’ associates and successors, and is now
merged into that of the recently organized Maryland Geological Sur-
vey (1896).

An outline of the present knowledge of the physical features of
Maryland is embraced in Part III. This is largely based upon the
work of Dr. Williams and his associate and successor, Dr. Clark,
together with the results of work accomplished since the organization
of the new survey. This summary is free of references, and is a.
most clear and readable presentation of existing information.

A valuable and exhaustive bibliography and cartography of Mary-
land comprise Part IV. These were compiled mainly by Dr. E. B.
Mathews and are rendered more serviceable to investigators by the
addition of brief statements of the contents of the paper or character
of the map.

The volume closes with a report upon magnetic work in Mary-
land (Part V.), prepared by Dr. L. H. Bauer, formerly of the U. S.
Coast and Geodetic Survey. The magnetic elements have been de-
termined ata number of points, and the results of the work will be
of value to all land surveyors. This report also includes a brief ac-
count of the history and purpose of a magnetic survey.

The volume is well illustrated by seventeen lithographic maps and
views, and the excellence of the typographic workmanship is unusual
in publications of its kind. Maryland is to be congratulated not alone
upon the contents, but also upon the prompt appearance and attractive
form of the first report of her new geological survey.

Review of Recent Geological Literature. 377

Vol. II., which will contain a description of the building and
decorative stones of the state, is promised for the coming winter.
F. B.

Orthoclase as Gangue Mineral in a fissure Vein. By WALDEMAR
Linperren. (Am. /. Sci., 155, ¢18-420.)

After noting the rather sparing occurrence oi the feldspars in true
veins, the author describes a silyer-gold vein near Silver City, Idaho,
having a gangue of quartz and orthoclase. The orthoclase is of the
variety adularia, and the evidence of its aqueous origin is followed by
an analysis yielding SiOz, 66.28; Al-Os, 17.93; KO, 15.12; NaO, 0.25;
undet., 0.42; total, 100.00. W. ©. C.

Notes on Rocks and Minerals from California. By H. W. 'TurNrER.
(Am. J. Sct., 155, 421-428.)

This paper describes: 1. a peculiar quartz-amphibole dioryte, with
very complete analysis of the dioryte and its component amphibole;
2. a new amphibole-pyroxene rock from Mariposa county; 3. a quartz-
alunite, with an analysis of the alunite, which occurs as an efflores-
cence; 4, zircon from gravels; 5, molybdenite from several localities;
6, tellurium, selenium and nickel in gold ores; 7. carbonaceous ma-
terial in quartz from gold veins east of the Mother lode; 8. berthierite
irom Tuolumne county. WaOs.C:

Mineralogical Noteson Anthophyliite, Enstatite and Beryl (Emerald)
Srom North Carolina. By J. H. Pratr. (Am. /. Sct., 255, 429-432.)

The anthophyllite and enstatite are from the great dunyte dikes of
Western North Carolina ; and two analyses of each are given. The
emerald is from vein of pegmatyte in Mitchell county, and was _ not
analyzed. ; Ware Gk

The Jerome (Kansas) Meteorite. By Henry .S. WasHinearon. (Am.
J. Stt., 155, 447-454)

This meteorite, about 65 pounds in weight, is a deeply oxidized
mass, made up of numerous chondrules of bronzite and olivine, with
iragmental crystals of these minerals and pyroxene, and small angu-
lar masses of nickel-iron (4.3 per cent.). No troilite was recognized,
but the analysis indicates that it was originally present to the extent
of 5.2 per cent. An approximate chemical analysis and an analysis of ©
the nickel iron, which contains 10.01 per cent. of nickel, are followed
by exhaustive analyses of both the soluble and insoluble portions; and
from these analytic data the mineralogical composition is calculated,
the chief constituents, in order of abundance, being olivine, bronzite,
limonite (secondary), oligoclase, troilite, pyroxene, nickel-iron and
orthoclase. Ww. O. C

On the Origin of the Corundum assoctated with the Peridotytes in
North Carolina. By J.H. Pratr. (Am. /. Sct., 156, 49-05.)

The peridotyte (dunyte or olivine rock) is a basic, magnesian, plu-
tonic rock forming lenticular dikes and bosses in gneiss, and the
corundum is invariably found on the borders of these masses, between

378 The American Geologist. December, 1898

the dunyte and gneiss. The author’s conclusion, which appears to
be well sustained by the facts, is that the corundum is not in any sense
a secondary mineral, but dates from the original solidification of the
dunyte, having existed in solution in the molten mass of the dunyte
at the time of its intrusion and separated out among the first minerals
as the mass began to cool. The dunyte magma, holding in solution
the chemical elements of the different minerals, would be like a sat-
urated liquid, and as it began to cool the minerals would crystallize
out, not according to their infusibility, but according to their solubility
in the molten magma. The more basic portions, according to the
general law of cooling and crystallizing magmas, being the most in-
soluble, would be the first to separate out. These would be the
oxides containing no silica, such as chromite, spinel and corundum.
The important experiments of Morozewicz with molten basic glasses
are cited as fully corroborating this view; and it is noted that the
crystallization of the corundum and other oxides would begin on the
outer border of the mass where cooling was most rapid. Convection
currents would then tend to bring new supplies of material carrying
alumina into this outer zone, where it would be deposited as corun-
dum. This is essentially Becker’s theory of fractional crystallization;
and it is noted that the high fluidity of these very basic magmas is a
very favorable condition. Nilo Ox

Erionite, anew Zeolite. By ArtTHuR S. Eaxte. (Am. /. Sct., 156,
66-68.)

This mineral occurs as very fine, white, pearly and woolly threads,
associated with opal in a rhyolyte-tuff from Durkee, Oregon. Analy-
sis gives: SiOs, 57.16; AlzOs, 16.08; CaO, 3.50; MgO, 0.66; K2O, 3.51;
NaO, 2.47; H.O, 17.30; total, 100.68. Allowing one molecule of
water as hydroxyl, as the hydration experiments indicate we obtain
the formula Hz Sis Ale Ca K: Naz Ow + 5H2O. This is analogous
to the formula for stilbite with the calcium largely replaced by alka-
lies; but in other respects the new zeolite has no resemblance to stil-
bite. The name refers to its woolly appearance. An analysis of the
associated milky opal gave: SiOz, 95.56; H2O, 4.14; and a trace of alum-
ina. Win Ov Ce

Metamorphism of Rocks and Rock Flowage. By C. R. Van Hise.
(Am. J. Sci., 156, 75-91, Bull. Geol. Soc. Am., 9, 269-328.)

This important contribution to dynamical geology, which is con-
densed from a partly written treatise on metamorphism and the meta-
morphic rocks, is mainly a physical study; but the important coopera-
tion of chemical agencies is fully recognized in the paragraphs on
chemical action and its relations to heat and pressure, the upper and
lower physico-chemical zones, etc. Vant Hoff’s law that “on the
whole, the preponderating chemical reactions at lower temperatures
are the combinings (associations) which take place with the develop-
ment of heat; while the reactions preponderating at higher tempera-
tures are the cleavings (dissociations), which take place with the ab-

nee

Review of Recent Geological Literature. 379

sorption of heat,” is made a basis principle of the discussion; and the_
contrasts of the upper and lower zones of the earth’s crust resulting
from this law and the natural antagonism of heat and pressure are
traced out in hydration, the mutual replacements of oxygen and sul-
phur, carbon dioxide and silicon dioxide, and the tendency to develop
in the upper zone minerals of lower specific gravity with consequent
expansion of the rocks, and in the deeper- seated zone minerals of
higher specific gravity, with consequent ‘contraction of the rocks. In
both the: phiysical, and chemical categories, alike at lesser and greater
depths, water is recognized as the one important and essential. me-

dium of alteration; and an almost inappreciable proportion of water
“is regarded as sufficient fot extensive’ and rapid metamorphism, in

which. it may act solely as agent, suffering neither gain nor loss. In
this connection the author cites the experiments of Barus, according
to which 180°C. is a critical temperature for the solution of glass in
water, the action being very slow below this temperature and aston-
ishingly rapid above it. The solution of the glass and crystallization
of its derived minerals are essentially contemporaneous and continu-
ous processes, involving, in the absence of hydrous derivatives, no
necessary diminution of the water, which may continue its work as
a mineralizer indefinitely and so rapidly as to dissolve and deposit in
crystalline form a volume of glass equal to that of the water in about
half an hour, from which the author calculates that, even if the rate
for rocks be only one-thousandth that for glass, a rock formation
could be dissolved and crystallized 50,000 times by one per cent. of
water in a mountain-making period of 150,000 years. WeeOsnG

Mineralogical Notes. By C.H.Warren. (Am./. Sci., 156, 116-124.)

This paper describes: 1. Melanotekite, a basic silicate or iron ses-
quioxide and lead, from Hillsboro, New Mexico, the analyses of ex-
ceptionally pure material indicating for this species and Kentrolite,
the corresponding basic silicate of manganese sesquioxide
and lead, the formula Fe:(Mns)PbsSizO;5, instead of Fe2(Mn:) Pb.
Siz Os heretofore accepted. 2. Pseudomorphs after phenacite, from
Greenwood, Maine, in which gigantic crystals up to twelve inches in
diameter having the form of phenacite have been completely replaced
by a mixture of quartz and cookeite, with not a trace of beryllium re-
maining. 3. Similar pseudomorphs after large crystals of topaz from
the same locality. 4. Crystallized tapiolite (tantalate of iron and
manganese) from Topsham, Maine, which is distinguished by its tet-
ragonal form from its orthorhomic dimorph, tantalite, and by its com-
position from the corresponding dimorphous niobates, mossite and co-
lumbite. 5. Crystallized tantalite from Paris, Maine, which is shown
by its very high specific gravity (7.26) not to be columbite, while the
absence of manganese adds to its chemical interest. 6. Cobaltiferous
smithsonite from Boleo, Lower California, which had been mistaken
for the rare hydrated cobalt carbonate, remingtonite, but which is
found by analysis to contain 39.02 per cent, of ZnO and only 10.25
per cent. of CoO. W. O. C.

380 The American Geologist. December, 1898

Sélosbergyte and Tinguayte from Essex County, Mass. By Henry
S. WasHinaton. (Am. /. Sci., 156, 176-157.)

The sdlosbergyte forms a dike four feet wide cutting granite, and
is specially distinguished by the presence of glaucophane and riebeck-
ite. One complete analysis is given and compared with four analyses
from other regions; and from the analysis the mineral composition is
computed, the chief constituents, in order of abundance, being,—albite,
orthoclase, glaucophane, riebeckite, quartz and titanite. In this con-
nection an analysis is also given of the Quincy granite in which T. G.
\Vhite had reported a blue hornblende which he referred to glauco-
phane; analyses of four foreign granites are quoted for comparison;
and the calculation of the mineral composition gives, in order of
abundance, quartz, albite, orthoclase, riebeckite and glaucophane, the
riebeckite largely predominating over the glaucophane. The analyses
are of special interest as pointing to the existence of a purely iron-
alumina glaucophane.

The tinguayte also occurs as a dike in the granite; and its most
notable characteristic is the occurrence in it, apparently as an original
constituent, of a large proportion (37.4 per cent.) of analcite. As
before, the analysis is compared with the similar rocks of other re-
gions and the mineral composition is deduced therefrom. __W. O. C.

Distribution and Quantitative Occurrence of Vanadium and Molyb-
denum in Rocks of the United States. By W. F. HiLtLesprann. (Am.
J. Sct., 156, 209-210.)

The analytic data show the quantitative occurrence and distribution
of vanadium in a large number (57) and variety of igneous rocks, in a
few of the component minerals of these rocks, and in a few metamor-
phic and secondary rocks. Two of the samples in the last series were
highly composite, one representing 253 sandstones and the other 408
limestones. The conclusions shown by a comparison of these data
are: that vanadium occurs in quite appreciable amounts in the more
basic igneous and metamorphic rocks, up to .o8 per cent. or more,
of V2Os, but seems to be absent or nearly so from the highly siliceous
ones; that the chief source of the vanadium is the heavy ferric-alumin-
ous silicates—the biotites, pyroxenes, amphiboles; that limestone and
sandstones contain only very small amounts of vanadium; that molyb-
denum is confined to the more siliceous rocks; and so far has been
found only in traces in these. Wis Oe Gs

An Occurrence of Dunyte in Western Massachusetts. By G.C. Mar-
vin. (Am. J. Sct., 150, 244-248.)

The dunyte or olivine rock, of which only two other occurrences
are known in North America, forms an irregularly elliptical boss of
distinctly igneous origin, about 1,000 by 2,000 feet in extent, in the
town of Cheshire. The olivine is extensively serpentinized, and the
original accessories include chromite, magnetite and picotite. The
olivine, purified by the Thoulet solution, gave on analysis: MgO,

51.41; SiOz, 40.07; FeO, 4.84; AlzOs, 1.94; H.O, 1.03; total, 99.29.
WwW. 0. C.

Review of Recent Geological Literature. 381

Chemical and Mineral Relationships in Igneous Rocks. By JosEPH
P. Ippines. (/. Geol., 6, 279-237.)

This is an attempt to correlate the mineral composition of igneous
rocks with the chemical composition of their magmas; that is, of each
rock asa whole. The chief difficulties are: first, the variable composi-
tion of the rock making minerals, quartz alone having an absolutely
fixed composition, and no element occurring only in one mineral; sec-
ond, the fact that no fixed association of minerals necessarily results
from the crystallization of a magma, the result being largely con-
trolled by the physical conditions. To avoid undue complexity, the
author confines his attention to the more important rock-making
minerals, including quartz, feldspathic minerals, micas, pvroxenes,
amphiboles, olivine and magnetite. The empirical and dualistic for-
mulas are given for each species; and. the latter are classified in ac-
cordance with the ratios of the protoxide and sesquioxide bases to the
silica. After quoting briefly some of the laws governing the rela-
tions of the mineral and chemical composition formulated in an earlier
paper, the author discusses in greater detail and with the aid of dia-
grams, the relations particularly of quartz, and of leucite, nephelite
and sodalite, thus making more evident the interdependence of the
various minerals on one another and on the chemical composition
of the magma. ; Wiss iOue Ce

A Study of some Examples of Rock Variation. By J. Morcan
CuemMents. (/. Geol., 6, 372-392.)

The rocks in question include diorytes, gabbros, norytes and peri-
dotytes occurring in the Crystal Falls iron-bearing district of Michi-
gan. Petrographic descriptions and chemical analyses of the several
types are followed by discussion of their chemical relations, the com-
plete analyses, percentages of the chief oxides, and atomic propor-
tions of the metals being presented in tabular form, and the author
concludes that the rapid changes in mineralogical composition and
texture in a single rock exposure, and the changes thus occasioned
from one rock into another through intermediate facies show very
clearly the intimate relationship of the rocks to one another, and war-
rants the assumption that they all belong to a geological unit.

W:: 0...

Notes on some Igneous, Metamorphic and Sedimentary Rocks of the
Coast Ranges of California. By H. W. Turner. (/. Geol.. 6, 483-400.)

The rocks considered in this paper include: 1. Metabasalts and
diabases, formerly regarded as metamorphic sandstones, of which ten
analyses are quoted without discussion. 2. Serpentine, which has also
been regarded as, in part at least, altered sedimentary rocks, but which
the author holds to be, in the main, at least, of igneous origin. Nine
analyses, representing five localities are quoted, showing great uni-
formity of composition and indicating that olivine or rhombic pyrox-
ene must have been a prominent constituent of all of the original
rocks from which the serpentines were derived. 3. The Franciscan or

382 The American Geologist. December, 1898

Golden Gate formation. 4. The San Pablo formation, which contains
layers of rhyolytic tuff or pumice, of which two partial analyses are
given. W. O. CG.

Syentte-porphyry Dikes tn the Northern Adirondacks. By H. P.
Cusuine. (Bull. Geol. Soc. Am., 9, 2379-250.)

These dikes, of which fourteen have been discovered, and which are
shown by their field relations to be younger than the pre-Cambrian
gneisses and anorthosytes which constitute the mass of the Adiron-
dacks, and older than the Potsdam sandstone, consist of a sub-acid,
holocrystalline rock chiefly composed of acid feldspars (microperthite,
albite, orthoclase and microcline) and _ biotite, with less abundant
quartz and hornblende, and accessory magnetite, hematite, apatite and
titanite, and various secondary species. Three original analyses are
given, selected to represent the mean and extremes of composition;
and from these the percentages of the component minerals are de-
duced. In the discussion of the petrologic relationships of the dikes,
numerous other analyses of the related rocks are quoted. Wi O. C:

Clay Deposits and Clay Industry in North Carolina. By HEINRICH
Ries. (North Carolina Geol. Surv., Bull. 1}, 1-157.)

Although regarded as a merely preliminary report, this is a fairly
comprehensive, if not a detailed, account of the clays of a great state.
But it is not of local interest only, for the admirable introductory
sections, forming nearly half the work, and covering the chemical
and physical properties, mining and preparation, of the clays is gen-
eral, and more specifically of the kaolins or china clays, pottery
clays, fire clays and brick clays, must prove of general interest and
value. Under the chemical properties of clays are discussed: the
fluxing impurities, including the alkalies, compounds of iron, lime and
magnesia; non-fluxing impurities, including silica titanium, organic
matter and water; analytic methods; and the rational analysis of clays.
The descriptive sections include nearly seventy original analysis of
North Carolina clays by Prof. Chas. Baskerville of the State Univer-
sity; and these are reported in tabular form at the end of the report.
Each analysis gives the silica, alumina, ferric oxide, lime, magnesia,
alkalies, moisture and water; and in certain cases the ferrous oxide,
organic matter, sulphur and titanic oxide were also determined. By
way of rational analyses, on which the value of a clay chiefly depends,
the clay substance (pure kaolin), free and total fluxes are given in
each case; and for the china clays also the percentages of quartz and
feldspar in the sand. Wiss Our

Weathering of Alnoyte in Manheim, New York. By C. H. Smytu,
JR. (Bull. Geol. Soc. Am., 9, 257-208.)

The alnoyte, which forms several small dikes in the Calciferous
‘sand rock” on East Canada creek, is an ultrabasic type, consisting
largely of biotite and serpentine derived from the original olivine, the oli-
vine itself being extremely rare; and the minor constituents are mag-

Review of Recent Geological Literature. 383

netite, apatite and perofskite, with secondary calcite. The investi-
gation is largely based upon the methods established by Merrill. Both
the fresh rock and its highly weathered faces were analyzed, the chief
points of interest being, as usual, the increase of ferric oxide and water
and diminution of ferrous oxide, alkaline earths and silica in the
weathered material. From the analyses the loss for the whole rock,
and the percentages of each constituent retained and lost are calcu-
lated. The titanic oxide is shown to be one of the most resistant
constituents of the rock, its behavior being almost identical with that
of alumina, so that the two are taken together as the basis for com-
parison. The iron oxides have proved almost equally insoluble, the
apparent net increase being due, of course, to per oxidation of FeO.
The large proportion of magnesia and lime in the weathered rock in-
dicate that the process is far from complete; and in harmony with this
view 93.60 per cent. of the weather rock was found to be soluble in
hydrochloric acid and sodium hydrate solution. The contrast between
the surface weathering and deep-seated alteration of rocks, the rate
of decomposition of biotite, and the time of wathering are also dis-
cussed. Biotite appears to weather rapidly in acid rocks and slowly
in basic rocks simply because, while it is chemically one of the weak-
est constituents of the former, it is one of the most resistant constitu-
ents of the latter, the difference being relative only. Warne:

Om ACEROCAREZONEN ett bidrag till Ktinnedomen om Sktines Ole-
nidenskifrar, af JOH. CHR. MoBerG och HyELMAR MOLLER [Geol.
fren i Stockholm férhandl., Bd. 20, Hf. 5, 1808. ]

This valuable contribution of Moberg and Moller to a knowledge

of the upper Olenus schist of Scania largely extends our knowledge of
~ the range of the genus Acerocare. Hitherto we have thought it was con-
fined to the layer immediately beneath the Dictyonema shale, but this
essay shows that it had a wider range, viz: through the whole thickness
of the Peltura or upper Olenus schist, and that the type of the genus A.
ecorne Angelin, in place of coming at the top of this fauna, is really at
the base. The genus is carried up through the Peltura beds by several
species, one described by Linnarsson, and several new, by these authors.
They also describe a new species of Parabolina, and give. fuller illustra-
tions of P. heres Brégger, than had been given by the author of the spe-
cies. The figures of this species differ considerably from Brégger’s, no-
tably in the heavy wrinkling of the test, and the deep glabellar furrows.
One valuable feature of this work is that young head shields are figured,
thus giving a much better conception of the genetic relationship of the
species, than the figures of adult shields alone would give.

The authors relegate Olenus acanthurus Ang. which Brégger had
placed in Protopeltura (Brég) to Parabolina, Salter. Acerocare is re-
garded as a genus closely related to Peltura, differing from it in the
spineless pygidium etc.

An excellent feature of this article is that restorations of the complete
form of most of the species described are given, and the hypostome also
in most cases. Five excellent plates accompany the article, and leave

384 The American Geologist. December, 1898

one little to wish for as regards a complete knowledge of these interest-
ing species of the upper Olenus beds.

The species described are Acerocare ecorne Ang., A. (Cyclognathus,
Lin’rs.) wzcropygum Lin’rs, A. norvegicum, n. sp. A. granulatum, n. sp.
A. paradoxum, n.sp., A. tulbergt, n. sp., A. claudicans, n. sp., Para-
bolina acanthura Ang., P. heres Brégg., P. megalops, n. sp., Orthis, sp.

G. F. M.

UEBER CALYMMENE, Brongniart, von J. F. POMPECKJ, in Miinchen.
[Neues Jahrbuch fiir Mineralogie, Geologie und Palzeontologie, Stuttgart,
1808.]

Dr. Pompeckj has made an exhaustive study of the genus Calym-
mene, Brongn. He cites F. Schmidt as having divided the genus into
three sections. 1. Calymmene, sens strict., with the type C. fuberculata
Dalm (= blumenbachi). 2. Pharostoma Corda, Type, C.fulchra Barr.,
and 3. Ptychometopus, F. Schmidt. The author supports Brégger in
considering Calymenopsts, Bergeron, as superfluous, C. #//acovi being a
variety of Ez/oma ornatum Ang.

Dr. Pompeckj proposes an arrangement of the forms referred to Cal-
ymmene somewhat different from F. Schmidt’s. He would divide the
genus into two main sections; the first (A) containing the groups (1)
Pharostoma Corda, and (2) Calymmene, s.strict., F. Schmidt. Both of
these Pompeckj would include under CALYMMENE proper. The second
section (B) to contain the groups of (3) C. ¢vzstanz Brong. (4) of C. arago
Row., and (5) of Ptychometopus, F. Schmidt. This section Pompeckj
calls SYNHOMALONOTUS.

Frech considers Euloma, Angelin, as the stem genus of Pharostoma,
but Pompeckj regards Bavarilla of Barrande as holding this place. He
looks to Neseuretus, Hicks, as the source of the B section, and he re-
gards Homalonotus also as having sprung from this source (page 248).
Should not Section B then be referred to Homalonotus rather than Cal-
ymmene? G. F. M.

The Special Report on Kansas Coal. ERASMUS HAWORTH; W. R.
CRANE. (Univ. Geol. Sur. Kansas, vol. I], 347 pp., Topeka, 1808.)

The third volume of geological notes, that has been recently is-
sued under the auspices of the University of Kansas, presents much
interesting information regarding the sunflower state. It purports to
be a special report on the coals. As a whole it gives us our first
connected review of the Kansas Carboniferous below the so-called Per-
mian.

When it is remembered that this work is done ‘argely without
financial compensation, too much credit cannot be bestowed upon
the Kansas geologists who have thus so generously given their serv-
ices to their State. It behooves the great State of Kansas, so rich
in mineral wealth, to be equal to the occasion and aid this most
worthy undertaking in a manner more befitting her already exalted
position. Professor Haworth, speaking not of his own labors but of
those who have rendered him assistance says that the greater part

Review of Recent Geological Literature. 385
of this work “was done wholly without expense to the State, and
that the remainder was done at such a nominal expense that it is al-
most without a parallel in the history of public investigations of
this kind.”” The same remark is equally true of all of this Kansas work.
It is the plain duty of the State to encourage these efforts so well
begun. From a financial standpoint, let alone all others, it would
be a good investment to Kansas to extend liberal aid. For every
dollar thus expended the return is a thousand to the citizens at large.
Such commendable activity as is shown by the Kansas workers should
not be allowed to go without public recognition in the way of ample
funds to still further enable this most laudable enterprise to go on
as it should.

The first part of the volume, by professor Haworti, gives a com-
plete summary of all the work previously done by the instructors
and students of the university during the prosecution of the univer-
sity geological survey, so far as this has pertained to the coal meas-
ures. The various terranes before recognized are described anew,
some new divisional lines are made and some new names of forma-
tions are proposed. The classification now presented is essentially
as follows:

Divisions of the Kansas Coal Measures.

Cottonwood Cottonwood shales.
Formation | Cottonwood limestone.
Linestones and shales, to
Wabaunsee which names have not
Formation | _ been given as yet.
Burlingame limestone.
Osage shales.
Topeka limestones.
Calhoun shales.
Epes Bue nee ti Deer Creek limestone.
easures ormation | Tecumseh shales.
Lecompton limestones.
Lecompton shales.
Douglas : Orexd limestone.
Formation |} Lawrence shales.
Garnett limestones.
._ | Lane shales,
Pottawatomic | [o]a limestones.
Formation Thayer shales.
Erie limestones.
Upper Pleasanton shales.
Altamont limestone.
Miardaton Lower Pleasanton shales.
Lower Coal Formation | Pawnee limestone.
Measures Labette shales.
Oswego limestones.

Cher’kee sh’l’s | Cherokee shales.

The second part, by Mr. W. E. Crane, which makes up the greater
portion of the volume, is devoted chiefly to the commercial aspects
of the Kansas coal, the methods of mining and the character of the
mine machinery. A considerable portion of this embraces also many
details regarding the stratigraphy and the local peculiarities of sec-

386 The American Geologist. December, 1898

tions. The chemical and physical properties of the coals are consid-
ered at length. The statistics of output and values are graphically
shown. The report closes with a mining directory and a chapter on
mining laws.

Much as we are indebted to professor Haworth and his assistants
for the great mass of facts presented, there are certain features for
which geologists are not so thankful. Some of these features were
prominently displayed in the earlier volumes of the series. They
were passed over at the time for the reason that it was thought that
succeeding accounts would have these evils corrected. Instead they
have been greatly intensified. It therefore seems well to call atten-
tion briefly to a few of them. While it is acknowledged that much
of the work in Kansas was done under great difficulties, and that
the principal author was plunged suddenly from his chosen field of
mineralogy to the wholly different one of stratigraphy, these condi-
tions hardly justify the position taken by him. Outsiders seek, and
seek in vain, for any progressive purpose in the proposing of so many
undefined and hence meaningless and useless titles for insignificant
beds, and various terranes. The author himself appears to have ques-
tioned the good form of such action. The excuse that they are “only
local” seems worse than no excuse at all. To be sure the beds are
local. But as soon as they are printed the names are the common
property of the entire geological world; and necessarily form a part
of geological literature, even if most of them must be relegated to
the vast realm of the spurious.

Since the appearance of the first volume of the series, of which
the work under consideration is a part, geologists especially interested
in the American Carboniferous have been not a little curious to know
just what principles professor Haworth worked upon in his Kansas
investigations. Volume III gives for the first time an insight into
those principles. The startling statements are made that ““Nomencla-
ture, coupled with the claims of priority, is the bane of the scientist;”
and that “It frequently happens that an investigator in a new field
knowingly substitutes new names for old, sometimes with good rea-
son, and sometimes apparently largely to have his name connected
with future discussions of allied subjects.” These two sentences form
the key-note to the whole theme, and enable us to understand more
easily why professor Haworth has been unable to solve satisfactorily
the problems presented.

The principles involved in the consideration of some of the points
hereafter mentioned are of far wider than local significance. Did
they but affect Kansas alone the subject might be dismissed without
further reference. The first of the sentences just quoted is indeed
remarkable, and particularly as coming from the source that it does.
Its author can hardly have intended its literal meaning, yet perusal of.
the rest of the paragraph precludes any other interpretation. Most
people regard nomenclature as a means whereby thoughts are exactly
expressed. Terms are employed in the same way that the carpenter

Review of Recent Geological Literature. 387
uses his tools. Should we paraphrase the sentence just alluded to,
and say that “his tools are the bane of the catpenter,’’ we would be
generally regarded as talking at random. We have identically the
same conditions. There are but few of us that could be induced to
believe that progress is possible along any such lines. It is not the
use oi rational nomenclature but the constant abuse of it that causes
widespread irritation among scientists.

The second sentence quoted appears to apply too truly to Kan-
sas to have it emanate from professor Haworth. It has been with
keen regret that geologists have witnessed how professor Haworth
has so persistently and perfectly ignored his predecessors in the Kan-
sas field. In all the three volumes he has published not a single
definite statement is gleaned that any one else had ever seen the coal
measures of that region. No one could ever gather from these notes
that such able geologists and indefatigable workers as Swallow,
Hawn, Meek, Broadhead, Hayden, St. John, Hay, Mudge or New-
berry had ever crossed the Kansas boundaries. Yet their labors are
vastly more important than those carried on during the past lustrum
Even the footnotes, with few exceptions, are manifestly merely ref-
erences to show Haworth’s “claims of priority.” One cannot help
concluding from these writings that there was certainly ‘“‘an investi-
gator in a new field.”

In this connection we cannot gloze it over “on account of an
inexcusable ignorance of the subject at hand on part of the writer.”
We cannot but feel that a gross injustice has been done not only to
the earlier writers, by ignoring completely their work, much of it far
superior to that done to-day, but also to the geologists now actively
interested in the region, who have no means of connecting the results
of the pioneers with those lately added. These pioneers are worthy
of better treatment. If ever there was a proper place to bring togeth-
er all the results accomplished in Kansas it was in connection with
the work under consideration. The contrast is enormously accentu-
ated by the careiul efforts of Prosser, who has published some of his
results in the same volumes, and who has so correlated the earlier
work as to increase its value ten-fold, at the same time vastly illumin-
ating his own.

Little need be said of professor Haworth’s arrangement of the
terranes that he recognizes. A classification based solely upon “‘con-
venience” cannot endure. The many incongruities arising from
grouping upon this principle are only too apparent. These may be
considered in another connection, and so passed over here.

The remarks on priority show a marvelous inappreciation of the
common canons of nomenclature. Yet this is not wholly unexpected
when we consider in what a baneful light all terminology is held by
the Kansan author. If some of the ordinary rules of the use of
terms had even a slight consideration many of the formidable diffi-
culties raised by professor Haworth would have been easily dispelled
before they appeared. The general statements regarding the use of

388 The American Geologist. December, 1898

Primary, Secondary, Permian and similar geological terms are as
much out of place that they indicate a lack of recognition of the broad
fact that terminology must change with conceptions that have been
outgrown.

By wholly ignoring the excellent and extensive labors of his pre-
decessors professor Haworth has fallen into grievous errors regarding
many of his new names. It will necessitate herculean “struggles to
avoid obscurity” of some of them. Marmaton is essentially the same
subdivision which Bain, several years ago, gave the name Appanoose.
Erie has been already preoccupied a dozen times. Thayer was a
term given by Broadhead, 30 years ago, to the same shales at the
same locality in Neosho county. Broadhead’s full and lucid descrip-
tion of identically the same section could be with great advantage to-
day substituted for the one given by Haworth. Lawrence, lola and
Cherokee are about the only important titles out of all the numerous
ones proposed that are likely to stand. Surely, even a little attention
to previous work would have removed most if not all of the conditions
“compelling the new invesigator to discontinue some of the terms and
making it desirable if not necessary for him to introduce others.”
With no consistent principles to be guided by, perhaps little else
could be expected. There is, at least, no internal evidence that pro-
fessor Haworth has given the slightest attention to that generally rec-
ognized principle that terminology reflects systematic arrangement.
The latter is manifestly an expression of genetic relationship. Classi-

fication based entirely on convenience is no classification at all. It is
merely titled chaos. CiaRs ke

Contribution & l étude micrographique des terrains sédimentatres,
par LUCIEN CayEux. (Mémoires de la Société Géologique du Nord.
tome 4, pp.589. 10 pls. quarto, 1897. Lille.)

This is in part a contribution to metamorphism, and it is certainly
one of the most important that have been made to that subject. It
has long been known that amongst the older rocks, and especially
the Archean, the constituent fragmental grains undergo transforma-
tions which result in new minerals and in compact crystalline rocks.
In this work the process is studied at its commencement, and in the
Cretaceous and Tertiary strata. The research is carried on with
thoroughness and deliberation. In the examination the author has
included also the microscopic organisms of all the formations de-
scribed. Thesé formations are the Jurassic and Cretaceous of the
Paris basin, the Cretaceous of Belgium, the Eocene shales and glau-
conitic sands of the north of France and the chalk of the Paris basin.

All literature on these formations, at least so far as it bears on
the microscopic structure and organisms, appears to have contributed
to the wealth of reference and to the grasp of the subject shown by
the author; and at the close of the volume is an extended bibliography
embracing 312 works, beginning in 1745 with Linneus and ending
with Gosselet in 1897.

Review of Recent Geological Literature. 389

It is useless to attempt to fully analyze this work. A simple men-
tion of the secondary minerals discovered in these sedimentary strata
will convey but an imperfect idea of the transformations that are de-
scribed. Glauconite figures very largely, also quartz and the com-
pounds of lime; among the species mentioned being orthoclase, gyp-
sum, calcite, leverrierite, opal, pyrite, limonite, chalcedony, chert.
Amongst the clastic minerals are mentioned zircon, tourmaline,
(these two also sometimes apparently formed zz sztu) rutile, mag-
netite, orthoclase, plagioclase, anatase, brookite, chlorite, staurotide,
garnet, apatite, corundum, ilmenite, disthene, and several others un-
determined. A plate is devoted to the microscopic crystals. Their
forms are so perfect that nearly all of them appear not to have suffered
any transportation, a fact which suggests that many if not all of them
are indigenous.

The author has given much time to the study of the various forms
of glauconite and to the question of its origin. He brings to light
some new facts and verifies others not well known. Amongst the
characters of this mineral he emphasizes the following: With gen-
erally rounded forms and olive green color, its grains are also some-
times black; in thin section they vary from yellowish green to dark
green with specific gravity from 2.2 to 2.83. Most glauconite is
homogenous in structure, but it is sometimes granular, globular and
concretionary. It also acts as a pigment in a manner similar to
limonite, when it is impossible to separate it from the siliceous or
argillaceous substratum which it colors. It is cleavable, as shown
by the author in 1893, a fact which has since been recognized by La-
croix who has determined the basal cleavage (oor) similar to that of
the micas and chlorites. This cleavage is difficult, fine or coarse, in-
equally spaced, rare or frequent. The partings are rarely straight,
being more often slightly sinuous or wavy. They are parallel or con-
vergent; they even cut each other, when they are very irregular.
These features are illustrated by figures.

Glauconite sometimes includes mineral and organic substances,
the former being usually quartz (which very rarely is traversed by
rutile) feldspar and calcite, the latter microscopic forms and frag-
ments of foraminifera and radiolarians. Sollas has also noted cocco-
liths and coccospheres while Murray and Renard found in the glan-
conite collected by the Challenger, particles of quartz, magnetite and
other minerals. ;

The cleavable grains of glauconite are sensibly polychroic. This
was announced by Cayeux in 1892, and, as with black mica, the great-
est absorption takes place when the cleavage is parallel to the
principal section of the analyser. The mineral is then dark green,
and when perpendicular to the cleavage its color changes to light
yellow.

By the aid of studies of Calderon and Chaves, and especially of

*Mineralogie de la France et de ses colonies, I 407.

390 The American Geologist. December, 1898

Lacroix, M. Cayeux is now able*to add to the simple announcement
of double refraction of glauconite made by him in 1892, the essential
characters of a crystalline substance, viz: it is biaxial (sometimes ap-
parently uniaxial), the angle of the optic axes being from 30 to 40
degrees. The value of 7g—”p is about 0.020, and from analogy
with the micas and chlorites it is supposed to be monoclinic. Glau-
conite has also been found, though very rarely, to have a radiated-
fibrous or concretionary structure, giving a black cross in thin sec-
tion.

In the discussion of the phenomena of alteration of glauconite,
the author bears directly on the theory of Spurr of the origin of the
great deposits of iron ore of the Taconic in Minnesota. He says:
“The products of decomposition of glauconite are hydrates of the
oxide of iron and pyrite.” Most frequently alteration begins to ap-
pear at the periphery and extends progressively and regularly to the
interior. It also reaches the center of the grains by way of fissures
which traverse them in all directions. The products of decomposi-
tion appear not only throughout the areas that are altered but they
migrate sometimes and color the surrounding parts and encrust. sur-
rounding minerals. Alteration may make its first appearance at the
center of the grains as in the Meule de Thivencelles, for example,
where it affects a great number of grains; grains are there
found transformed into hydrated iron oxide excepting only a slight
superficial zone which remains intact.”

Matthew has also found a notable amount of oxide of iron in the
Cambrian of New Brunswick wherever foraminiferal remains, and
hence glauconite, occur, the two being reasonably taken to be com-
plementary.

According to Dr. Cayeux: (1) Glauconite has been formed in
other places than those in which its grains now exist, and has shared
in the processes of mechanical transport in the same manner as grains
of sand. (2) It contains inclusions of other minerals, such as magne-
tite and quartz. (3) Forms incrustations on crystals of orthoclase,
microcline, etc., penetrating along the cleavages even to the center
of the grains. (4) Serves as a pigment in the same manner as
limonite. (5) Takes the form g/obudlatre, like nascent quartz crystals
described by Fouqué, and by combination of these globules grows
into larger and larger groups and masses. (6) Its grains take com-
plete outward form but do not sometimes fill up the interior, only a
skeleton of glauconite occupying the space. (7) Continues to increase
after the deposit of the rock which contains it. (8) Forms at different
dates, cotemporary with the consolidation of the rock and posterior
to it. (8) Sometimes replaces calcite, taking the form of calcite rhom-
bohedrons. (9) Is usually, but not always, dependent on organic sub-
stances for its genesis. N. H. W.

Authors’ Catalogue. 391

Monte Y> AUTHORS CATALOGUE
OF AMERICAN GEOLOGICAL LITERATURE,
ARRANGED ALPHABETICALLY.*

Bagg, R. M., Jr.

The Cretaceous foraminifera of New Jersey. (Bull. 88, U. S. Geol.
Sur., pp. 89, 6 pls. 1898.)
Bailey, ‘‘Prof.”’

The bay of Fundy trough in American Geological History. (Trans.
Roy. Soc. Can., 2nd ser., vol. 3, sec. 4, pp. 107-116, 1897.)
Boyer, Charles L. (Lewis Woolman and).

Fossil mollusks and diatoms from the Dismal swamp, Virginia
and North Carolina; indication of the geological age of the deposit.
(Proc. Acad. Nat. Sci. Phil., Part 2, April-Sept. 1898, pp. 414—)

Brush, Geo. J.

Manual of Determinative Mineralogy, with an introduction on
Blowpipe Analysis. Revised and enlarged, with new tables for the
identification of minerals, by Samuel L. Penfield, 15th Edition, 1808,
pp. 312. John Wiley and Sons, New York.

Claypole, E. W.

Glacial Theories—cosmical and terrestrial. (Am. Geol., vol. 22,

pp. 310-315, Nov. 1898.)

Dawson, Sir J. W.

On the genus Lepidophloios as illustrated by specimens from the
coal formation of Nova Scotia and New Brunswick. (Trans. Roy.
Soc. Can., 2nd Ser., vol. 3, Sec. 4, pp. 57-77, 14 pls., 1897.)

Dawson, Geo. M.

Annual Report. [Geological Survey of Canada.] New Series,
vol. 9, 1896, (1808), pp. 816, maps; contains the director’s summary
report for 1896, and reports of Tyrrell, Bell, Low, Bailey, Hoffman
and Ingall, and 20 plates.

Eastman, C. R.

Some new points in dinichthyid osteology. (Am. Nat., vol. 32,
Pp. 747-768, Oct. 1808.)

Ells, R. W.

Notes on the Archean of Eastern Canada. (Trans. Roy. Soc.
Can., 2nd Ser., vol. 3, Sec. 4, pp. 117-124, 1897.)

Fitzpatrick, -T. J.

The drift section and the glacial striz in the vicinity of Lamoni,
Iowa. (Iowa Acad. Sciences, vol. 5, pp. 105-106, 1 pl., 1808.)
Gannett, Henry.

Lake Chelan, (Nat. Geol. Mag., vol. 9, Oct. 1808, pp. 417-428.)

*This list ineludes titles of articles received up to the 20th of the preceding

month, including general geology, physiography, paleontology, petrology and
mineralogy.

392 The American Geologist. December, 1898

Girty, Geo. H.

Description of a fauna found in the Devonian Black shale of east-
ern Kentucky. (Am. Jour. Sci., Nov. 1898, pp. 384-394, 1 pl.)
Merrick, Cr:

The occurrence of copper and lead in the San Andreas and Ca-
ballo Mountains. (Am. Geol., vol. 22, pp. 285-291, Nov. 1808.)

Hidden, W. E.

Occurrence of sperrylite in North Carolina. (Am. Jour. Sci., Nov.
1898, pp. 381-383.)

Hill, R. T. (and T. Wayland Vaughan).

The Lower Creteceous Gryphzeas of the Texas region. (Bull. No.
151, U.S. Geol: Sur. pp:"60)-35) piss, s1808.)

Hopkins, Thos. C.

Concentric Weathering in sedimentary rocks. (Bull. Geol. Soe.
Am., vol. 9, 1897, pp. 427-428, 3 pls.)

Ingall, E. D.

Section of Mineral Statistics and mines; annual report for 1806.
(Geol. Sur. Can. Ann. Report, New Series, vol. 9, 1898, pp. 172.)
Keyes, C. R.

Some geological formations of the cap-au-gres uplift. (Proc.
Iowa Acad. Sciences, vol. 5, pp. 58-63, 3 pls., 18908.)

Keyes, C. R.

Carboniferous formations of the Ozark region. (lowa Acad.
Sciences, vol. 5, pp. 55-58, 1808.)

Keyes, C. R.

Geographic development of the Crimea. (lowa Acad. Sciences,
vol..5, pp. 52-54, 1808.)

King, Francis P. (W. S. Yates, S. W. McCallie and).

A preliminary report on a part of the gold deposits of Georgia.
(Bull. 4-A, Geol. Sur. Georgia, pp. 542, maps, 21 pls., 1896.)

Ladd, Geo; E:

Geological Phenomena resulting from the surface tension of
water. (Am. Geol., vol. 22, pp. 267-285, pl., Nov. 1898.)

Lucas 7 ana:

Contributions to paleontology. (Am. Jour. Sci, Nov. 18098, pp.
399-4C0. )

Manson, Marsden.

The laws of climatic evolution. (Brit. Assc. Ady. Sci., Bristol
meeting, 1898.)

Marsh, O. C.

The value of type specimens and importance of their preservation.
(Am. Jour. Sci., Nov. 1808, pp. 401-405.)

Marsh, O. C.
The origin of Mammals. (Am. Jour. Sci., Nov. 1898, pp. 406-499.)

Authors’ Catalogue. 393

McCallie, S. W.

The occurrence and history of gold. (Bull. No. 4-A, Geol. Sur.,
Georgia, 1896, pp. 7-32.)

McCallie, S. W.(W. S. Yates and Francis P. King).

A preliminary report on a part of the gold deposits of Georgia.
(Bull. 4-A, Geol. Sur. Georgia, pp. 542, maps, 21 pls., 1896.)

McGee, W. J.

The Geospheres. (Nat. Geog. Mag., vol. 9, Oct. 1898, pp. 435-
447.)

Rawson, F. Leslie.

Some lava flows of the western slope of the Sierra Nevada, Cali-
fornia. (Bull. No. 89, U. S. Geol. Sur., pp. 74, 11 pls., 1808.)
Sardeson, F. W.

Intraformational conglomerates in the Galena series. (Am.
Geol., vol. 22, pp. 315-323, pl., Nov. 1898.)

Sardeson, Fae.

Remarks on the loess. (Proc. lowa Acad. Sciences, vol. 5, p. 11,
1898, [abstract ].)
madd, J. JE.

Degradation of loess. (Proc. Acad. Sciences, vol. 5, pp. 46-51,
1808. )
Tyrrell, J. B.

Report on the Doobaunt, Kazan and Ferguson rivers, and the
northwest coast of Hudson bay, and on two overland routes from
Hudson bay to lake Winnipeg. (Geol. Sur. Can., Rep. 9, New
Series, May 10, 1897, 11 plates.)

Upham, Warren.

Giants’ kettles near Christiania and in Lucerne. (Am. Geol., vol.
22, pp. 291-299, Nov. 1808.)

Vaughan, T. Wayland (Robt. T. Hill and).

The Lower Cretaceous Grypheas of the Texas region. (Bull.
roi, WU. S. Geol. Sur., pp. 66, 35 pls., 1808.)

Walcott, C. D. .

Fossil Meduse. (Mon, XXX, U. S. Geol. Sur., pp. viii and 201,
pls. 47, 1808.)

Walker, T. L.

Causes of variation in the composition of igneous rocks. (Am.
Jour. Sci., Nov. 1898, pp. 410-415.)

Weeks, F. B.

Bibliography and index of North American geology, paleontology,
petrology and mineralogy for the year 1896. (Bull. No. 149, U. S.
Geol. Sur., pp. 152, 1897.)

Weeks, F. B.

Bibliographyand index of North American geology, petrology and

mineralogy for the year 1897. (Bull. 156, U. S. Geol. Sur., pp. 130,
1808. )

394 The American Geologist. December, 1898

Winchell, N. H.

Origin of the Archean igneous rocks. (Am. Geol., vol. 22, pp. 299-
310, Nov. 1808.)

Woolman, Lewis (and Charles S. Boyer).

Fossil mollusks and diatoms from the Dismal swamp, Virginia and
North Carolina; indication of the geological age of the deposit. (Proc.
Acad. Nat. Sci., Phil., Part 2, April-Sept. 1898, pp. 414—)

Wright, G. Frederick.

Glacial Observations in the Champlain-St. Lawrence valley. (Am.
Geol., vol. 22, pp. 333-334, Nov. 1898.)

Yeates, W. S. (S. W. McCallie and Francis P. King).

A preliminary report on a part of the gold deposits of Georgia.
(Bull. 4-A, Geol. Sur. Georgia, pp. 542, maps, 21 plates, 1896.)

PERSONAL AND SCIENTIFIC NEWS:

Mr. Oscar H. HERSHEY, of Freeport, Illinois, returned
home November 14th, from the Isthmus of Panama, where,
in this anda former journey, he has united geological ob-
servation with gold prospecting.

Mr. ). B. TyrrELL, for 15 years past one of the geolo-
gists of the Canadian survey, spent the past summer in the
Yukon district. He is now planning to engage in economic
explorations and surveys in the vicinity of Dawson, leaving
Ottawa about the first of January. Hewill be prepared to ~
report on the extent, character and value of mining proper-
ties.

Dr. M. E. Wapsworru has resigned the presidency of
the Michigan College of Mines, to take effect May 15, 1899.
Dr Wadsworth was also granted leave of absence from Dec.
23, prox. In his letter of resignation he calls attention to
the growth of the institution since his administration began,
and to the excellent condition in which he leaves it. ‘The
stormy and arduous duties” of president of such an institu-
tion have not such attraction as the quiet and peace of a
professorship, and Dr. Wadsworth desires to complete
sundry scientific work which was begun long ago—an ac-
complishment which he. has found impossible with the exec-
utive duties of the presidency resting on him.

Mr. GEorGE BIRD GRINNELL, in Sczence of November 18,
describes a visit made by him to the Blackfoot mountains in
northwestern Montana, accompanied by Mr. J. B. Monroe.
Two important geographic points were established, viz: the
location and character of the Pumpelly glacier, and the po-

Personal and Scientific News. 395

sition of Avalanche: basin. This glacier rises to the hight
of several hundred feet above the face of a lofty cliff, over
which portions of the glacier are constantly falling, with
tremendous reports which are heard for a long distance.
This glacier is a part of the southward flow of the ice cap
which covers almost the whole of the Blackfoot mountain,
The Blackfoot glacier flows northeastwardly from the peak
of Blackfoot mountain, six or seven miles long and three or
four miles wide. Another glacier flows northerly between
Mt. Kainah and Mt. Jackson, while from Mt. Jackson, the
highest of all these mountains, a number of smaller glaciers
flow down to the timber line. Another glacier of consider-
able dimensions lies in Pinchot’s basin, southward from Mt.
Jackson.

Dr. Orto NORDENSKJOLD, UPSALA, returning from Alaska
where he has spent the summer, passed two days at Minne-
apolis recently. Dr. Nordenskjéld has now seen the ex-
tremes of the western hemisphere, having spent last year in
southern Patagonia and Terra del Fuego. His reports on
these expeditions are awaited with much interest.

Mr. J. E. Spurr, in the service of the U: S. Geol. Survey,
has also recently returned from Alaska, stopping at Minne-
apolis en route to Washington. He left Seattle with a party
of seven April 4, and was picked up by the steamer Dora
Oct. 31 at Katmai, which was the last trip of the last steam-
er from the northern portion of Alaska for the season of 1808.
By way of Cook’s inlet, Mr. Spurr reached the Sushitna, and
then the Kuskokwim, descending the latter. Then he ascend-
ed the Kanektok to Togiak lake from w hich he descended the
Togiak river. Then partly by a coastal route and partly by
small rivers he reached Nushagak, from which he went
across Bristol bay, via Naknek river and lake and over the
Alaskan peninsula to Katmai where he was making prepara-
tions for a possible winter sojourn when he was unexpectedly
rescued by the Dora on her last trip.

Tue Merric System. The following bill, approved by
the Committee on Coinage, Weights and Measures, is pend-

ing in Congress:

Be it enacted by the Senate and House of Representatives of the
United States of America in Congress assembled, That from and after
the first day of July, nineteen hundred, all the departments of the Gov-
ernment of the United States, in the transaction of all business requiring
the use of weights and measurement, except in completing the survey of
the public lands, shall employ and use only the weights and measures of
the metric system, and from said first day of July, nineteen hundred, the
metric system of weights and measures shall be the ie standard of
weights and measures recognized in the United States

UNDE EO VOR 7 oie

A

Agassiz Geological Explorations in the
West Indies, R. T. Hill, 265.

Age of Niagara Falls, as indicated by
the Erosion at the Mouth of the Gorge,
G. Frederick Wright, 260.

American Association for the Advance-
ment of Science, 130; 248 ; 266.

Anderson, C. C., Keport on the Water
Powers of Georgia, 190.

An occurrence of Dunyte in
Mass., G. C. Martin, 830.

Another Episode in the History of Ni-
agara River, J. W. Spencer. 259.

A Recently Discovered Cave of Celes-
tite Crystals at Putin Bay, Ohio, G.
Frederick Wright, 261.

western

B

Bagg, R. M., Jr., The occurrence of Cre-
taceous fossils in the Eocene of Mary-
land, 370.

Bain, H. Foster, (and A. T. Leonard)
The Middle Coal Measures of the West-
ern Interior Coal Field, 251; Intergla-
cial deposits in Towa, 326.

Baker, Marcus, 129.

Baur, Dr. Geo., 130.

Bison Latifrons and Bos Arizonica, W.
P. Blake, 247.

Blake, W. P., Remains of a Species of
Bos in the Quaternary of Arizona, 65.

Brogger, W. C., Ueber die Verbreitung
der Euloma- Niobe fauna in Europa, 236.

Bryson, John, Drift Formations of
Long Island, 245.
Brush, Geo. J. (and S. L. Penfield),

Manual of Determinative Mineralogy,
328.

c

Calvin, 8., Geological Survey of New
Jersey, 240; Interglacial deposits in
lowa, 326.

Calymmene, Brong., J. F. Pompeckj, 384.

Cayeux, L., Contribution al’ étude des
terrains sédimentaires, 388.

Chemical and mineral relationships in
Igneous rocks, J. P. Iddings, 381,

Clark, W. B,, 375.

Classification of Coastal Forms, F. P.
Gulliver, 253.

Clayey Bands of the Drift of the Delta
of the Cuyahoga River, compared with
those of the Glacial Delta at Trenton,
N.J., G. F. Wright, 250.

Claypole, E. W., 62; Microscopical
Light in Geological Darkness, 217;
Glacial Theories—Cosmical and Ter-
restrial, 310.

Clements, J. M., A study of some exam-
ples of rock variation, 381.

Continental divide in Nicaragua, C. W.
Hayes, 253.

Contribution & 1’ étude micrographique
des terrains sédimentaires, L. Cayeux,

Crawford, J., Recent Severe Seismic
Disturbances in Nicaragua, 56; 259.

Clay industry in N. C., H. Ries, 382.

Cretaceous fossils in the Eocene of Mary-
land, R. M. Bagg, Jr., 370.

Crosby, W. O., History of the Blue
Hills Complex, 263.

Cubanite at Butte, Montana, H. V.
Winchell, 245.

Cushing, H. P., Syenite-porphyry dikes
in the northern Adirondacks, 382.

D

Daly, R. A., 130.

Dane E. §., Text-book of Mineralogy,
328.

Davis, W. M., 266.
Developments of
G. Tight, 252.

Ditferentiation of Magmas, 113.

Dikes in the vicinity of Portland, Maine,
E. C. E, Lord, 335.

Dissection of the Ural Mountains, F. P.
Gulliver, 253.

Distribution of vanadium and molyb-
denum in the United States, W. F.
Hillebrand, 380.

Drift Formations of Long Island, J.
Bryson, 245.

Drygalski’s Glacial Studies in Green-
land, 323.

the Ohio River, W.

Index.

E

Eakle, A. S., Erionite, a new Zeolite, 378
Eastman, C. R., Occurrence of Fossil
Fishes in the Devonian of Iowa, 287.

EDITORIAL COMMENT.
The Question of the Differentiation of
Magmas, 113.
The West Coast of Greenland, 189.
Drygalski’s Glacial Studies in Green-
land, 323. :
Elftman, A. H.,The St. Croix River
Valley, 58; Geology of the Keweena-
wan Area in Northeastern Minnesota,
ie 131
Erionite, a new zeolite, A. S, Eakle, 378.
Evidences of Epcirogenic Movements
Causing and Terminating the Ice-age,
Warran Upham, 250.

F

Fairchild, H. L., Glacial Geology in
America, 154; Basins in Glacial Lake
Deltas, 254.

Feldspars in Serpentine, Southeastern
Pennsylvania, T. C. Hopkins, 256.

Fjords and Submerged Valleys of Eur-
ope, Warren Upham, 101. 5

Fluctuations of North American Glaci-
ation shown by Interglacial Soils and
Fossiliferous Deposits, Warren Up-
ham, 258.

FossILs.

Tetradium Cellulosum Hall, 16.
Bos Arizonica, 65, 247.
Calymmene, 384.

G

Geography and Resources of the Sibe-
am Island of Sakalin, Benj. Howard,
26).

Geological Phenomena resulting from
the Surface Tension of Water, T. L.
Watson, 267.

Geology of the Environs of Albu-
querque, New Mexico, C. L. Herrick, 26,

Geology of the Yukon Gold District, J.
E. Spurr, 49.

Geological Survey of Canada; sum-
mary report for 1897, 52.

Geological Survey of New York; fif-
teenth report, 324.

Geology of the Keweenawan area in
Minnesota, IIT, A. H. Elftman, 131.

Geological Survey of New Jersey, J.C.
Smock, 239.

Geological Survey of Icwa, S.
240,

Geology and Geography at the Ameri-
can Association Meeting, 249.

Giants’ Kettles near Christiania and
in Lucerne, Warren Upham, 291.

‘Gilbert, G. K., 129.

Grabau, A. W., Paleontology of the Cam-
brian Terranes of the Boston Basin,
264.

Glacial Observations in the Champlain
St. Lawrence Valley, G. F. Wright, 333.

Glacial Theories—Cosinical and Terres-
trial, E. W. Claypole. 310.

Calvin,

397

Glacial Geology in 13 tO
Fairchild, 154.

Glacial Phenomena in Okanogan coun-
ty, Washington, W. L. Dawson, 203.

Glacial Rivers and Lakes in Sweden,
Warren Upham, 230.

Glacial Waters in the Finger-lake re-
gionof New York, H. L. Fairchild, 249.

Great terrace of the Columbia, I. C. Rus-
sel, 362.

Grinnell, G. B., 394.

Gulliver, F. P., Classification of Coastal
Forms, 253; Dissection of the Ural
eianteins, 253; Note on Monadnock,

Gurich, Dr. George. Das Palwozoicum
Polnischen Mittelgebirge, 53.

America,

‘H

Hall, James, 266, Fifteenth report, New
York Survey, 324.

Haworth, E., Special report on Kansas
coal, 384.

Hayes, W. C.. The Continental Divide
in Nicaragua, 253.

Herrick, C. L., Geology of the Environs
of Albuquerque, New Mexico, 26; Oc-
currence of Copper and Lead in the San
Andreas and Caballo Mountains, 285.

Hershey, O. H., 394.

Hill, R. T.. The Agassiz Geological Ex-
plorations in the West Indies, 2H5.,

Hillebrand, W. F., Distribution of
Vanadium and Molybdenum in the
United States, 380.

History of Mining and Quarrying in
Minnesota, Warren Upham, 51.

History of the Blue Hills Complex, W.
O. Crosby, 263.

Hitchcock, C. H.. 265; The Hudson
River lobe of the Laurentide Ice-sheet,
2D: P

Hollick, Arthur, Some Features of the
Drift on Staten Island, 249.

Hopkins, T. C., Some Feldspars in
Serpentine, Southeastern Pennsylva-
nia, 256.

Hovey, H. C., The Region of the
Causses in Southern France, 256.

Howard, Benj., Geography and Re-
sources of the Siberian Island of Saka-
lin, 261.

Hudson River Lebe of the Laurentide
Ice-sheet, C. H. Hitchcock, 255.

Hypothesis of a Cincinnati Silurian
Island, A. M. Miller, 78.

Iddings, J. P., Chemical and mineral re-
lationships in igneous rocks, 381.

Intraformational Conglomerates in the
Galena Series, F. W. Sardeson, 315.

Interglacial deposits in [Lowa;a Sym-
posium, by Calvin, Leverett, Bain, Ud-
den, 326.

J

Jerome (Kansas) meteorite, H. S. Wash-
ington, 377.

398

K

Keyes, C. R., Remarks on the Classifi-
cation of the Mississippian Series, 108;
The Principal Missourian Section, 251.

L

Ladd, G. E., Geological phenomena re-
sulting from the surface tension of wa-
ter, 367.

Lane, A. C.,Magmatic Ditterentiation
in the Copper-bearing Series, 251; Note
on a Method of Stream Capture, 252.

Leonard,*A. T. (and H. Foster Bain),
Middle Coal Measures of the Western
Interior Coal Field, 251.

Leverett, Frank, Interglacial Deposits
in Lowa, 326.

Lindgren, W.,
mineral, ee

Lord, E. CG. .On the dikes in the vicin-
ity of Posina, Maine, 335.

Low, A. P., Traverse of Northern Lab-
rador, 326.

Orthoelase as a gangue

M

Magmatic Differentiation in the Rocks
ot the Copper-bearing Series, A. C.
Lane, 251.

Manual of Determinative Mineralogy,
Geo. J. Brush, 8. L. Penfield, 328.

Martin, G. C., An occurrence of dunyte
in western Massachusetts, 3:0.

Matthew, G. F.,Studies on Cambrian,
Faunas, 50; Oldest Paleozoic Fauna,
262.

Marsh;O. C., 63.

Maryland Geological Survey, 375.

McCalley, H., The Valley Regions of
Alabama (Paleozoic Strata), 52.

McCallie, S. W., Phosphates and Marls
of Georgia, 193.

McGee, W. J., 129.

Mecklenburg’ or Baltic Moraines, War-
ren Upham, 43; Metric system, 395.

Metamorphism of rocks and rock flow-
age, C. R. Van Hise, 378 3

Microscopical Light in Geological
Darkness, E. W. Claypole, 217.

Middle Coal Measures of the Western
Interior Coal Field, H. Foster Bain and
A. 'I’. Leonard, 251.

Miller. A. M., The Hypothesis of a Cin-
cinnati Silurian Island, 78

Mineralogical notes, C. H. Warren, 379.

MINERALS.

Celestite, 261; Cubanite, 245; Mesolite,
258; Tourmaline, 251, 265; Feldspar,
256; Thomsonite, 347; Lintonite, 348:
Orthoclase, 377; Corundum, 377;
Erionite, 378; Melanotekite, 379;
Phenacite, 379 ; Topax, 379; Tapiolite,
379; Tantalite, 379; Smithsonite (co-
baltiferous,) 379.

Moberg och Moller, Om Acerocarezonen
ett bidrag till KAnnedomen om Skénes
Olenidenskiffrar, 383.

Monthly Authors’ Catalogue of Litera-
ture, 53, 124, 197, 240, 328, 391.

Mukai, Dr. Th., 1380.

Munthe, H.,On the Interglacial Sub-
mergence of Great Britain, 193.

Index.

N

Nordenskjold, O., 395.

Notes on rocks and minerals from Cali-
fornia, H. W. Turner, 377.

Notes on some igneous, metamorphic
and sedimentary rocks of the Coast
eeBees of California, H. W. Turner,

Note sur les Gisements d’or du Mexi-
gue, E. Ordonez, 124.

Note on a Method of Stream Capture,
A.C. Lane, 252,

Note on Monadnock, F. P. Gulliver,
253.
Note on the Characters of mesolite

from Minnesota, N. H. Winchell, 228.

Note on the Occurrence of Tourmalines
in California. C. R. Orcutt, 265.

Note on anthophyllite, enstatite and
beryl, J. H. Pratt, 377.

Northward on the Great Ice, R. E.
Peary, 123.

Oo

Occurrence of Copper and Lead in the
San Andreas and Caballo Mountains,
C. L. Herrick, 285.

Occurrence of Fossil Eishes in the De-
vonian in lowa, C. R. Eastman, 237.
Oldest Paleozoic Fauna, G. F. Mat-

thew, 262.

Oldest Known Rock, N. H. Winchell,
262.

Om Acerocarezonen ett bidrag till Kane-
domen om Skanes Olenidenskittrar,
Moberg och Moller, 383.

On the Interglacial Submergence of
Great Britian, H. Munthe, 193.

On the Development of Tetradram
Cellulosum Hall, R. Ruedemann, 16.
On the Origin of corundum in the
peridotytes of North Carolina, J. H.

Pratt, 377.

Ordonez, E., Note sur les gisements
d’or du Mexique, 124.

Orcutt, C. R., Note on the Occurrence
of Tourmalines in California, 265.

Origin of the Archean Igneous Rocks,
N. H. Winchell, 299.

Orthoclase as a gangue mineral, W.
Lindgren, 377.

Osage vs. Augusta, Stuart Weller, 12.

P

Paleontologische und Stratigraphische
Notizen aus Analolien, J. F. Pompeckj.
Byil,

Paleontology of the Cambrian Ter-
ranes of the Boston Basin, A. W. Gra-
bau, 264.

Paleozoicum Polnischen Mittelgobirge
Dr. Geo. Gurich, 53.

Patton, H. B., Tourmaline and Tour-
maline Schists from Belcher Hill, 251.
Peary, R. E., Northward over the

Great Ice, 123.

Penfield, Satie (and Geo. J. Brush),
Manual of Determinative Mineralogy,
328.

Periodic Variation of Glaciers, H. F.
Reid, 265.

Index. 399

Phosphates and Marls of Georgia, S.
W. McCallie, 193.

Physical Geegraphy of New Jersey. R.
D. Salisbury and C. C. Vermeule, !23.
ompeckj, J. F., Paleontologische und
stratigraphische Notizen aus Anato-
lien, 51; Ueber Calymmene, Brong., 384.

Pratt, J. H., Notes on Anthophyllite,
Enstatite and Beryl, 377; Origin of
Corundum, 377. '

Primitive Man in the Somme valley,
Warren Upham, 350, :

Principal Missourian Section, C. R.
Keyes, 251,

R

Raised Shorelines at Trondhjem, War-
ren Upham, 149.
Recent Severe Seisonie Disturbances in
Nicaragua, J. Crawford, 56; 259.
Region of the Causses in Southern
France, H. C. Hovey, 256. ;
Reid, H. F., Stratification of Glaciers,
pee? Periodic Variation of Glaciers,
Remains of a Species of Bos in the Qua-
ternary of Arizona, W. P. Blake, 65.
Remarks on the Classification of the
Mississippian Series, C. R. Keyes, i08.
Richardson, C. H., The Washington
Limestone in Vermont, 257.
Ruedemann, R., On the Development of
Tetradium Collulosum Hall, 16.
Russell, I. C., The great Terrace of the
Columbia, 362.

S

Salisbury, R. D., Physical Geography of
New Jersey, 123.

sandberger, Karl Ludwig Tridolin, 64.

Sardeson, F. W., Intraformational Con-
glomerates in the Galena Series, 315.

Significance of the Fragmental Eruptive
Debris at Taylor’s Falls, Minn., N. H.
Winchell, 72.

Smock, J. C., Geological Survey of New
Jersey, 239.

pay Eh, C. H., Jr., Weathering of Alnoyte,

Solosbergyte and tinguayte from Essex
Co. Mass., H. S. Washington, 380.

Some Features of the Drift on Staten Is-
land, A. Hollick, 249.

Special Report on Kansas Coal, E. Ha-
worth, 384.

Spencer. J. W., Another Episode in the
History of Niagara River, 259; Evi-
dence of recent Great Elevationin New
England, 262.

Spurr, J. E., Geology of the Yukon Gold
District, 49; 395.

St. Croix River Valley, A. H. Elftman, 58.

Stratification of Glaciers, H. F. Reid, 249.

Studies on Cambrian Faunas, G. F,
Matthew, 50.

Study of some examples of Rock Varia-
tion, J. M. Clements, 381.

Supposed Corduroy Road of the Late
Glacial Age at Amboy, Ohio, G. F.
Wright, 259.

Syenite-porphyry dikes in the northern
Adirondacks, H. P. Cushing, 382.

2)

T

Tarr, R.S., Wave-formed Cuspate Fore-
lands, 1; 61.

Text-book of Mineralogy, E.S. Dana, 328.

Thomsonite and lintonite from the north
shore of Lake Superior, N. H. Win-
chell, 347.

Tight, W. G., The Developmeut of thé
Ohio River, 252.

Time of Erosion of the Upper Mississippi,
Minnesota and St. Croix Valleys, War-
ren Upham, 258.

Torell, O. M,, 129.

Tourmaline and Tourmaline Schists from
eieher Hill, Colorado, H. B. Patton,

i.

Traverse of Northern Labrador, A, P
Low, 326.

Turner, H. W., Notes on rocks and min-
erals from California, 377; Notes on
some igneous, metamorphic and sedi-
mentary rocks of the Coast Ranges of

Jalifornia, 381.

Tyrrell, J. B., 394. '

U

Ueber die Verbreitung der Euloma-Niobe
Fauna in Europa, W.C. brogger, 236.
Udden, J. A., Interglacial Deposits in

fowa, 326.

Upham, Warren, The Mecklenberg or
Baltic Moraines, 43; History of Mining
and Quarrying in Minnesota, 51; Fjords
and Submerged Valleys of Europe, 101;
Raised Shorelines at Trondhjem, 149;
Glacial Rivers and Lakes in Sweden,
230; Geology and Geography at the
American Association Meeting, 248;
Evidences of Epeirogenic Movements
Causing and Terminating the Ice Age,
250: Fluctuations of North Ameriean
Glaciation shown by Interglacial Soils
and Fossiliferous Deposits, 258; Time
of Erosion of the Upper Mississippi,
Minnesota and St. Croix Valleys, 258;
Giants’ Kettles near Christiania and
in Lucerne, 291: Primitive man in the
Somme valley, 350.

Vv

Valley Regions of Alabama, H. McCalley,
52

Van Hise, C. R., Volume Relations of the
Original and Secondary Minerals in
Rocks, 252; Metamorphism of rocks
and rock flowage, 378. d

Vermeule, C. C., Physical Geography of
New Jersey, 123.

Volume Relations of Original and Sec-
ondary Minerals in Rocks, C. R. Van
Hise, 252.

Ww

Wadsworth, M. E., 394.

Warren, C. H.. Mineralogical notes, 379.

Washington, H.S., The Jerome (Kansas)
meteorite, 377; Solosbergyte and tin-
guayte from Essex Co., Mass., 380.

400

Washington Limestone in Vermont, C.
H. Richardson, 257. :

Waterpowers of Georgia, C. C. Anderson,
196,

Watson, T. F., Weathering of Diabase
near Chatham. Virginia, 85.

eared Cuspate Forelands, R. S.
Parmele

Weathering of Diabase near Chatham,
Virginia, T. L. Watson, 85.

Weathering of alnoyte in “Manheim, N.
Y.,C. H. Smyth, Jr., 382.

Weller, Stuart, Osage vs. Augusta, 12.

West Coast of Greenland, 189.

Winchell, H. V., Cubanite in Butte, Mon-
tana, 245.

Winchell, N. H., 62; Significance of the
Fragmental Eruptive Debris at Tay-

lndex.

lor’s Falls. Minnesota, 72; Oldest
Known Rock, 262; Note on the Charace-
ters of Mesolite from Minnesota, 22s;
Origin of the Archean Igneous Rocks,
299; Thomsonite and lintonite from the
north shore of lake Superior, 347.

Woodworth, Jay, 266.

Wright, Geo. F., Clayey Bands of the
Cuyahoya Delta compared with those
of the Glacial Delta at Trenton, N. J.,
250; Supposed Corduroy Road of late
Glacial Age at Amboy, Ohio, 259: The
Age of Niagara Falls as indicated by
the Erosion at the Mouth of the Gorge,
260; A Recently Discovered Cave of
Celestite Crystals at Put-in-Bay, Ohio.
261; Glacial Observations in the Cham.
plain—St. Lawrence Valley, 333.

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OIS-URBANA

085267836

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