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I
THE
American Geologist
A MONTHLY JOURNAL OF GEOLOTTT
AND
ALLIED SCIENCES
EDITORS AND PHOPHIETOBS
Florence Ba8€X)ic, Bryn Mawr^ Pa,
Chabi.es E. Beecrbe, JVetr Haven, Conn,
Samcel Calvist, Iowa City, Iowa.
John M. Clarke, Albany, N. Y. Persifob Fbazer, Philadelphia, Pa.
Edward W. Clatfole, Akron. Ohio. Ultb8E8 S. Ubamt, MinneapfAis. Minn
John £tericax, Ewsto,x, Pa. Wabrex Upham, St. Paul. Minn.
Marshmak E. WADSwoRTHt HouffMon, Mich.
Israel C. White, Morganiown, W, Va.
Newtox H. WmcHELL, Minneapolis, Minn.
VOLL^E XXI
Jaxuabt to Jcxe, 1898
MlSYEAPOLI^^, Ml99,
The Geoi>ogicai, TrBLi9^Hi%*, Compaxt
TeK FbaSKUY PlJ3tTTJ«r f.>^,. Pr>,
•ai^
[
CONTENTS.
JANUARY NUMBER.
Page
Joseph Francis James. G. K. Gilbert. [Portrait,
Plate I.] 1
The Determination of the Feldspars. N. H. Winchell.
[Plates II-VIII.] 12
The Pittsburg Coal Bed. I. C. White 49
Review of Recent Geological Literature. — SeventeeDth annual report
of the United States Greological Survey, Chas. D. Walcott, Di-
rector, 61. — Iowa Greological Survey, vol. 6, Annual Report, 1896,
with accompanying papers, S. Calvin, State Geologist, 64.— Vol-
canoes of North America: a reading lesson for students of Geog-
raphy and Greology, Israel C. Russell, 65.— Beitrftge zur Kennt-
niss einiger p&leozoischer Faunen Sud-Amerikas, von Herrn E.
Katsbr, 66. — Petrology for students. An introduction to the study
of rocks under the microscope, Alfred Barker, 67.— Greological
section from Moscow to Siberia and return, Persifor Frazer, 68.
Monthly AutJu>ra^ Catalogue of American Geological Literature, 68.
Correspondence. — The mechanical action of the Divining-Rod, M. E.
Wadsworth, 69.
Personal and Scientific. News, — New York Academy of Sciences, 72. —
A new meteorite, 73. — Cuvier prize, 74. — Iowa Academy of Scien-
ces, 74.
FEBRUARY NUMBER.
Additional Note on the Oceanic Current in the Utica
Epoch. R. RuEDEMANK. [Plate IX.] 75
Shell-Bearing Drift on Moel Tryfan. Warren Upham. . 81
Cote Sans Dessein and Grand Tower. C. F. Marbut.
[Plate X.] 86
The Geology of the Keweenawan Area in Northeastern
Minnesota. A. H. Elftman. [Plate XI.] 90
An Account of the Researches relating to the Great Lakes.
J. W. Spencer 110
IV Contents,
Editorial Comment, — A case of geological parasitism, 123.
Recent Geological Literature. — Geological Survey of New Jersey, 126.
Report on the Doobaunt, Kazan and Ferguson rivers and the
northwest coast of Hudson bay and on two overland routes from
Hudson bay to Winnipeg, J. Burr Tyrrell, 128. — Batesville
sandstone of Arkansas, Stuart Weller, 129.
Monthly Authors^ Catalogue of American Geological Literature, 131.
Correspondence, — Zirkelyte : a question of priority, 133.
Personal and Scientific News, 134.
MARCH NUMBER.
Geology of the St. Croix Dalles. II. Charles P. Berket.
[Plates XII and XIII.] 139
Residual Concentration by Weathering as a Mode of Gen-
esis of Iron Ores. James P. Kimball. 155
Oscillations of Level of the Pacific Coast of the United
States. William P. Blake 164
Valley Moraines and Drumlins in the English Lake Dis-
trict. Wareen Upham. 165
Some Methods of Determining the Positive or Negative
Character of Mineral Plates in Converging Polarized
Light with the Petrographical Microscope. M. E.
Wadswobth 170
The Geology of the Keweenawan Area in Northeastern
Minnesota. II. A. H. Elftman 175
Review of Recent CfeotogricaZ Ltiero^ ure.-PalsBontologiskaNotiser, Ger-
hard Holm, 188.— A Revision of the Puerco Fauna, W. D, Mat-
thew, 190. — Geology of Massanutten Mountain in Virginia, Ar-
thur CoE Spencer, 191.
Monthly Authors^ Catalogue of American Geological Literature, 192.
Correspondence. — Correlation of Moraines with Beaches on the Border
of Lake Erie, Frank Leverett, 195.— A new well at Rock Island,
111., J. A. Udden, 199.
Personal and Scientific News, 200.
APRIL NUMBER.
An Occurrence of Acid Pegmatyte in Diabase. T. A.
Jaggab. [Plate XIV.] 203
The Geology of the Environs of Tammerfors. J. J. Sed-
erholm 213
Contents. v
Note on Trellised Drainage in the Adirondacks. A. P.
Brigham. [Plat« XV.] 219
Some Resemblances between the Archean of Minnesota
and of Finland. N. H. Winchkll 222
Use of the term Augusta in Geology. Chas. R. Keyks 229
Drumlins in Glasgow. Warren Upham 235
Review of Recent Geological Literature, — Le Gypse de Paris at les min-
^raux qui 1' accompagnent, A. Lacroix, 244.
Monthly Authors^ Catalogue of American Qeological Literature^ 245.
Correspondence, — Archean Character of the Nucleus of the Antilles,
Persifor Frazer, 250. — The Interglacial deposits of Northeastern
Iowa, Samuel Calvin, 251. — The Weathered Zone (Yarmouth)
between the IlUnoian and Kansan Till Sheets, Frank Levekett,
254. — The Weathered Zone (Sangamon) between the lowan Loess
and Illinoian Till Sheet, Frank Leverett, 254. — Aftonian and
Pre-Kansan Deposits in Southwestern Iowa, H. Foster Bain, 255.
—Some Preglacial Soils, J. A. Udden, 262.
Personal and Scientific News, 264.
MAY NUMBER.
Major Frederick Hawn. G. (•. Broadhead. [Portrait.] 267
Geology of the St. Croix Dalles, III. C. P. Berkey.
[Plates XVII-XXI.J 270
The Parallel Roads of Glen Roy. Warren Upham 294
Tertiary and Quaternary Deposits in the Magellan Terri-
tories. Otto Nordenskjold 300
Champlain Submergence in the Narragansett Region.
Myron L. Fuller 310
Review of Recent Geological Literature. — The Geological Structure of
Shantung (Kiauchou) with particular reference to the Deposits of
useful minerals, F. V. RicHTHOFEN, translated by H. V. Winch
ELL, 321. — Water Resources of Indiana and Ohio, Frank Leverett,
324. — New Developments in Well Boring and Irrigation in Eastern
South Dakota, N. H. Darton, 325.
Monthly Authors^ Catalogue of American Geological Literature, 325.
Correspondence, On the formation of New Ravines, Edwin Linton, 329.
Personal and Scientific News, 330.
JUNE NUMBER.
Paleolith and Neolith. E. W. Claypole 333
Anthracite Coal in Arizona. William P. Blake 345
VI Contents,
Carboniferous Formations of Southwestern Iowa.
Charles R. Ketes 346
The Peneplain. R. S. Tarr 351
Studies on an Interesting Hornblende, occurring in a
Hornblende Gabbro, from Pavone, near Ivrea, Pied-
mont, Italy. Frank R. Van Horn 370
Ben Nevis, the Last Stronghold of the British Ice-
Sheet. Warren Upham 376
Review of Recent Geological Literature,— M.iner9\ Resources of the
United States, 1896, David T. Day, 380. — RecoDnaissance of the
Gold Fields of Southern Alaska, with some Notes on General Geol-
ogy, George F. Becker, 382.— Iowa Geological Survey. Admin-
istrative Reports, 382.— Kalgoorlite, a New Telluride Mineral from
Western Australia, E. F. Pittman, 383. — Catalogue of the Tertia-
ry Mollusca in the Department of Geology, British Museum, (Nat.
Hist.). Part I. The Australian Tertiary Mollusca, George F.
Harris, 383. — Vest&nafaltet: En Petrogenetisk Studie. (With an
English Summary), Helge Backstrom, 385.
Monthly Authors^ Catalogue of Ainerican Geological Literature, 387.
Correspondence, On Mr. Frank Leverett's "Correlation of Moraines
with Beaches on the Border of Lake Erie,'* J. W. Spencer, 393.
Personal and Scientific News, 396.
Index, 399.
Errata for Vol. XX.
Page 164, line 14, for "pot" read pool.
Page 165, line 13, for "rhyolite'* read hyalite.
Page 334. line 9 from the bottom, for '7om6idre" road tourbi^re.
Page 410, line 8. erase, the comma after vote.
Page 417, last line bat one, for ''deserve" read receive.
Page 418, line 5 from the bottom, for "Stepniow*^ read Spend iarow.
Page 420, line 2 of small type, for " west side" read east side.
Errata for Vol. XXI.
Page 70, line 1, for "Eraser" read Frazer.
Page 133, line 1, for "TyreU" read TyrreU.
Page 133, line 25, for "1898" read 1897.
Page 250, line 19 from the bottom, for "Nuclei" read Nucleus.
Page 250. line 2 from the bottom, for '%th" read 4th.
Page 328, line 10, in place of this line read ogists.] (Am. Qeol. vol. 21, pp. 213-219,
Apr. 1898.)
LiULA4. a
THE
AMERICAN GEOLOGIST
Vol. XXI. JANUARY, 1898. No. i
»
JOSEPH FRANCIS JAMES.
1857-1897.
By G. K. GiLBBBT, Washington.
(Plate I.)
Joseph Francis James was born in Cincinnati, Ohio, Feb-
ruary 8, 1857. He died in Hingham, Massachusetts, March
29, 1897. His father, Uriah Pierson James, a bookseller and
publisher of Cincinnati, devoted his leisure to scientific work,
chiefly the collection and study of the fossils of the Cincin-
nati group. As a boy Joseph was his father's companion on
collecting rambles and his scientific bent was thus early ac-
quired. Under his father's guidance he added the collecting of
living plants to the collecting of fossils, and his first publica-
tions were in the field of botany. Notes on rare or abnormal
plants appeared in the Botanical Gazette in 1877 ^^d 1879, but
he had already, at the age of sixteen, made a catalogue of the
local flora, which was afterward publisht by the Cincinnati
Society of Natural History.
In 1879 he removed to Los Angeles, California, where he
engaged in business and intended to make his permanent
home, but his plans were deranged by a disastrous fire and
finally abandoned. He then joined a railway construction
force and traveled through southern California, New Mexico
and Arizona, returning to San Francisco. This slow journey
in a land strongly contrasted, as to scenery and climate, with
the Ohio valley was an important factor in his education, and
was peculiarly effective in broadening his view of the relation
2 The American Geologist. January, i898
of life to environment. Numerous letters to newspapers were
written from the field, and his botanical notes were afterward
extensively used in more formal writings.
Returning to Cincinnati after two years of western life, he
was appointed (1881) custodian of the Society of Natural His-
tory, a position he held for six years, and he became also pro-
fessor of medical botany in the Cincinnati College of Phar-
macy. In the first part of this period his interest and work
continued in the field of botany, but paleontological and geo-
logical papers began to appear in 1884, the Cincinnati group
affording the principal themes.
In 1884 he was married to Sarah C. Stubbs, of Cincinnati,
who had been a teacher of botany and physiology in the city
high school. The union was a happy one, and his later labors
had the advantage of a sympathetic and efficient helpmeet.
With two sons she survives him.
In 1886 he was elected to the chair of botany and geology
of the Miami University, at Oxford, Ohio, but this position
was lost two years later through a disruption of the faculty
arising from religious prejudices. He was then for one year
professor of natural history in the Agricultural College of
Maryland. The work of teaching did not prevent the con-
tinuance of scientific study, and a number of papers from his
l)en appeared during this time. In these writings geology,
paleontology and botany are about equally represented, the
chief subjects being those which had occupied his attention at
Cincinnati.
While in Maryland he began work in connection with the
Ignited States Geological Survey and in 1889 was appointed
on the staff as assistant paleontologist, being assigned to the
division of paleozoic paleontology. The acquiring of this posi-
tion, which for years had been a cherisht ambition, proved
only the occasion of another disappointment, for the work it
i^ave him was largely of subsidiary and routine character, not
affording the opportunities for authorship to which he had
lookt forward. Two years later he received an appointment
in the United States Department of Agriculture, having past
liighest in a special examination by the Civil Service Com-
mission for an assistant vegetable pathologist, and in this
capacity he served for four years. Here also his duties were
Joseph Francis James. — Gilbert, 3
chiefly routine, and there was little gratification for his ambi-
tion in the direction of original research.
Having for many years struggled to support himself by
avocations in harmony with his scientific pursuits, and having,
either from the accident of environment or from lack of per-
sonal adaptation, suffered repeated rebuffs and discourage-
ments, he at last determined to adopt a more remunerative
profession and relegate science wholly to leisure hours. Still
retaining his official position and work, he devoted his even-
ings to the study of medicine, and in 1895 graduated from
the medical school of Columbian University. The following
winter was given to hospital work and bacteriologic study in
New York and London, and he then began practice in Hing-
ham, where the last year of his life was spent. A letter from
the. leader of an exploring expedition to Greenland, inviting
him to be the physician of the party, reacht his house the day
after his death.
Professor James's scientific work included the acquisition of
knowledge through research and its diffusion through popular
as well as technical publication. In research he was conscien-
tious and patient, dealing largely with details of classification,
generalization and explanation, and though enthusiastic, was
not tempted into the field of speculation. No brilliant discov-
eries nor theories were announced by him, but his contribu-
tions to knowledge are substantial and useful. In publication
he was not limited either to the record of his own investiga-
tions or to the pages of scientific journals, but being deeply
imprest with the importance of diffusing scientific knowledge,
he appeared often as an expounder of the work of others, and
made free use of newspapers and popular journals. The sub-
joined lists would have been greatly extended by including
reviews and book notices, and still more by adding the numer-
ous short articles addrest in one way or another to the general
public.
When religious beliefs were under fire at Oxford, profes-
sor James was accused of being an agnostic and defended as
being essentially a Unitarian. So far as I knew it, his religion
was an unswerving devotion to science. Science gave him
only a modicum of that fame which is so dear even to the
least selfish of her votaries, and she utterly failed to shield him
from adversity, but his fealty endured to the end.
4 The American Geologist, January. 189s
LIST OF PAPERS.*
Geological.
1885.
Evidences of beaches in the Cincinnati Group: Science, Vol. V,
March, 1885, pp. 231-233.
1886.
Geology of Cincinnati [Part I, Geology]: Jour. Cincinnati Soc.
Nat. Hist., Vol. IX, July, 1886, pp. 20-31 [84-95].
Geology and topography of Cincinnati [Part II, Topography]:
Jour. Cincinnati Soc. Nat. Hist., Vol. IX, October, 1886, pp. 136-141.
1887.
Well drilled for gas at Oxford, O.: Science, Vol. IX, June, 1887,
p. 623.
Account of a well drilled for oil or gas at Oxford, Ohio, May and
June, 1887: Jour. Cincinnati Soc. Nat. Hist., Vol. X, July, 1887, pp.
70-77; section.
Chalcedonized fossils: Science, Vol. X, September, 1887, p. 156.
1888.
Geological section of southwestern Ohio (Abstract): Proc. Am.
Assoc. Adv. Sci., 36th meeting (August, 1887), March, 1888, p. 211.
An ancient channel of the Ohio River at Cincinnati: Jour. Cin-
cinnati Soc. Nat. Hist., Vol. XI, July-October, 1888, pp. 96-101.
The Ivorydale well in Mill Creek Valley [Ohio] : Jour. Cincinnati
Soc. Nat. Hist., Vol. XI, July- October, 1888, pp. 102-104.
1889.
Remarks upon sedimentation in the Cincinnati Group: Jour. Cin-
cinnati Soc. Nat. Hist, Vol. XII, April, 1889, PP- 34-36.
Curiosities of natural gas: Pop. Sci. Monthly, Vol. XXXIV, April,
1889, pp. 821-826.
An ancient channel of the Ohio at Cincinnati (Abstract): Proc.
Am. Assoc. Adv. Science., 37th meeting (August, 1888), May, 1889,
p. 196.
The geology of the Montmorenci. A correction in a date: Am.
Geologist, Vol. IV, December, 1889, p. 387.
♦Professor James himself compiled a list of his papers "for the use
of his boys." That list forms the basis of the bibliography here given,
being abridged by the omission of newspaper articles, reviews and
short notes, and extended by the addition of a few articles publisht in
the last years of his life and one unpublisht paper. The work of veri-
fication and extension has been chiefly performed by Miss A. B. Daw-
son, and the botanical part has been revised also by Mr. E. S. Steele.
Joseph Francis James, — Gilbert. 5
1890.
On Laurentian as applied to a Quaternary terrane: Am. Geologist,
Vol. V, January, 1890, pp. 29-35.
Notes upon some of the papers presented to Section E of the Ameri-
can Association for the advancement of Science at the Toronto meet-
ing: Am. Naturalist, Vol. XXIV, February, 1890, pp. 808-810.
A cave in the Clinton formation of Ohio: Jour. Cincinnati Soc.
Nat. Hist, Vol. XIII, April, 1890, pp. 31-32.
On the Maquoketa shales and their correlation with the Cincinnati
Group of southwestern Ohio: Am. Geologist, Vol. V, June, 1890,
pp. 335-356. Postscript, Ibid., p. 394.
Section of the Makoqueta [Maquoketa] shales in Iowa (Abstract):
Proc. Am. Assoc. Adv. Sci., 38th meeting (August, 1889), July, 1890,
pp. 250-251.
On the name "Laurentian": Am. Geologist, Vol. VI, August, 1890,
pp. 133-134.
1891.
A brief history of the Ohio River: Pop. Sci. Monthly, Vol.
XXXVIII, April, 1891, pp. 739-748.
On the age of the Pt. Pleasant, Ohio, beds: Jour. Cincinnati Soc.
Nat. Hist, Vol. XIV, July, 1891, pp. 93-104. Two plates.
1893. '
The Cincinnati ice dam: Am. Geologist, Vol. XI, Mjirch, 1893,
pp. 199-202.
1894.
On the value of supposed Algae as geological guides: Am. Geolo-
gist, Vol. XIII, February, 1894, pp. 95-101.
The St. Peter's sandstone: Jour. Cincinnati Soc. Nat Hist., Vol.
XVII, July, 1894, pp. 1 15-135.
Paleontological.
1881.
Catalogue of the fossils of the Cincinnati Group. Cincinnati, 1881.
27 pages.
. 1881.
Two species of Tertiary plants: Science, Vol. Ill, April, 1884.
pp. 433-434.
1884- 1885.
Fucoids of the Cincinnati Group: Jour. Cincinnati Soc. Nat. Hist.,
Vol. VII, October, 1884, PP. 124-132; January, 1885, pp. 151-166;
4 plates.
1885.
Are there any fossil Algae? Am. Naturalist, Vol. XIX, February,
1885, pp. 165-167.
6 The American Geologist, January, isos
Remarks on a supposed fossil fungus from the Coal Measures:
Jour. Cincinnati Soc. Nat. Hist, Vol. VIII, October, 1885, pp. 157-159.
Remarks on some markings on the rocks of the Cincinnati Group,
described under the names of Ormathichnus and Walcottia: Jour. Cin-
cinnati Soc. Nat. Hist., Vol. VIII, October, 1885, pp. 160-163.
Remarks on the genera LepidoUtes, Anomaloides, Ischadites and
ReceptacuHtes, from the Cincinnati Group: Jour. Cincinnati Soc. Nat.
Hist., Vol. VIII, October, 1885, PP- 163-166.
1886.
Cephalopoda of the Cincinnati Group: Jour. Cincinnati Soc. Nat.
Hist., Vol. VIII, January, 1886, pp. 235-253. Plate.
Description of a new species of Gomphoceras from the Trenton
of Wisconsin: Jour. Cincinnati Soc. Nat. Hist, Vol. VIII, January,
1886, p. 255.
Note on a recent synonym in the palaeontology of the Cincinnati
Group: Jour. Cincinnati Soc. Nat Hist, Vol. IX, p. 39 [103].
1887.
Protozoa of the Cincinnati Group: Jour. Cincinnati Soc. Nat. Hist..
Vol. IX, January, 1887, pp. 244-252.
Sections of fossils: Science, Vol. X, October, 1887, p. 180.
1887-1888.
On the Monticuliporoid corals of the Cincinnati Group, with a crit-
ical revision of the species. By U. P. James and Joseph F. James:
Jour. Cincinnati Soc. Nat Hist, Vol. X, October, 1887, pp. 118- 141:
January, 1888, pp. 158-184; Vol. XI, April, 1888, pp. 15-47-
1887.
Microscopic sections of Corals: Science, Vol. X, November, 1887.
p. 252.
1888.
Sections of Fossils: Science, Vol. XI, January, 1888, p. 50.
On the Monticuliporoid corals of the Cincinnati Group, with a
critical revision of the species (Abstract): Proc. Am. Assoc. Adv. Sci.,
36th meeting (August, 1887), March, 1888, p. 223.
Monticulipora, a Coral and not a Polyzoon: Am. Geologist, Vol. I,
June, 1888, pp. 386-392.
American fossil Cryptogamia: Am. Naturalist, Vol. XXII, Decem-
ber, 1888, pp. 1 107- 1 108.
1889.
On variation, with special reference to certain Paleozoic genera:
Am. Naturalist, Vol. XXIII, December, 1889, pp. 1071-1087.
1891.
Fish remains of the Lower Silurian: Sci. American, Vol. LXIV,
February, 1891, p. 129.
Joseph Francis James. — Gilbert. 7
1891-1896.
Manual of the Paleontology of the Cincinnati Group: Part I, Jour.
Cincinnati Soc. Nat. Hist, Vol. XIV, April, 1891, pp. 45-72; Part II.
ibid., Vol. XIX, October, 1891-January, 1892, pp. 149-163; Part III,
ibid., Vol. XV, July, 1892, pp. 88-100; Part IV, ibid., Vol. XV, Octo-
ber, 1892-January, 1893, PP- 144-159; Part V, ibid, Vol. XVI, January,
1894, pp. 178-208; Part VI, ibid., Vol XVIII, April-July, 1895, pp.
67-88; Part VII, ibid.. Vol. XVIII, October, 1895-January, 1896, pp.
1 15-140.
1892- 1893.
Studies in problematic organisms-r-The Genus Scolithus: Bull.
Geol. Soc. America, Vol. Ill, 1892, pp. 32-44. No. II, The Genus
Fucoides: Jour. Cincinnati Soc. Nat. Hist., Vol. XVI, July-October,
1893, pp. 62-81, Plate.
1892.
The preservation of plants as fossils: Jour. Cincinnati Soc. Nat.
Hist, Vol. XV, July, 1892, pp. 75-78.
1893.
Remarks on the genus Arthrophycus, Hall: Jour. Cincinnati Soc.
Nat. Hist., Vol. XVI, July-October, 1893, PP. 82-86.
Fossil fungi. Translated from the French of R. Ferry, with re-
marks: Jour. Cincinnati Soc. Nat Hist., Vol. XVI, July-October,
1893, pp. 94-98.
1895.
[Daimonelix and allied fossil.] (Abstract of paper read before
Biological Society of Washington): Science, new series. Vol. I, April,
1895, p. 420.
Remarks on Daimonelix, or "Devil's Corkscrew," and allied fossils:
Am. Geologist, Vol, XV, June, 1895, pp. ZZ7'y^\ plates.
Sponges, recent and fossil: Am. NaturaUst, Vol. XXIX, June,
1895, pp. 536-545.
The first fauna of the earth: Am. Naturalist, Vol. XXIX, Octo-
ber, 1895, pp. 879-887; November, 1895, pp. 979-985-
The Paleontological writings of Uriah Pierson James, compiled,
annotated and illustrated by Joseph F. James. In manuscript, ready
for publication.
Botanical.
1879.
Catalogue of the flowering plants, ferns and fungi growing in the
vicinity of Cincinnati: Jour. Cincinnati Soc. Nat Hist., Vol. II,
pp. 42-68.
Seeds of Erodium cicutarium: Botanical Gazette, Vol. IV, Septem-
ber, 1879, p. 209.
8 The American Geologist. January, ih9.s
1880.
On the modes of distribution of plants: Pop. Sci. Monthly, Vol.
XVII, July, 1880, pp. 365-376.
A botanist in southern California: Am. Naturalist, Vol. XIV, July,
1880, pp. 492-498.
>Jotes on some California plants: Botanical Gazette, Vol. V, Octo-
ber, 1880, pp. 126-131.
1881.
On the geographical distribution of the indigenous plants of Europe
and the northeast United States: Jour. Cincinnati Soc. Nat. Hist, Vol.
IV, April, 1881, pp. 51-67.
The century plant: Jour. Cincinnati Soc. Nat. Hist, Vol. IV, Octo-
ber, 1881, pp. 234-236.
Botanical notes from Tuscon: Am. Naturalist, Vol. XV, Decem-
ber, 1881, pp. 978-987.
On the variability of the acorns of Quercus macrocarpa Michx. :
Jour. Cincinnati Soc. Nat Hist, Vol. IV, December, 1881-January,
1882, pp. 320-322; with plate.
1882.
Index to the genus Carex of Gtay's Manual: Botanical Gazette,
Vol. VII, supplement, February and March, 1882; 11 pages.
Parasitic plants: Vick's Monthly Magazine, Vol. V, November,
1882, pp. 330-332; with figures.
1883.
Pitcher plants: Am. Naturalist, Vol. XVII, March, 1883, pp.
283-293.
A revision of the genus Clematis of the United States (Abstract):
Proc. Am. Assoc. Adv. Sci., 31st meeting (August, 1882), 1883, p. 463.
Remarks on Dentaria as a sub-genus of Cardamine: Botanical
Gazette, Vol. VIII, April, 1883, pp. 206-207.
A revision of the genus Clematis of the United States, embracing
descriptions of all the species, their systematic arrangement, geograph-
ical distribution and synonomy: Jour. Cincinnati Soc. Nat. Hist., Vol.
VI, July, 1883, pp. 1 18-135.
Achenial hairs of Senecio: Science, Vol. II, August, 1883, pp.
201-202.
A letter from Dr. Torrey to Amos Eaton: Botanical Gazette, Vol.
VIII, September, 1883, pp. 289-291.
On the position of the Compositae and Orchidx in the natural sys-
tem: Am. Naturalist, Vol. XVII, December, 1883, pp. 1245-1254. Ab-
stract in Jour. Cincinnati Soc. Nat Hist., Vol. VI, 1883, pp. 169-170.
1884.
Expulsion of water from a growing leaf: Science, Vol. Ill, Febru-
ary, 1884, p. 245.
Joseph Francis James, — Gilbert. q
The Flora of Labrador: Science, Vol. Ill, March, 1884, p. 359.
Contributions to the Flora of Cincinnati: Jour. Cincinnati Soc. Nat.
Hist., Vol. VII, July, 1884, pp. 65-78.
How the dodder became a parasite: Pop. Sci. Monthly, Vol. XXV,
September, 1884, pp. 647-651.
A Reply [to criticism of Mr. James's remarks on Specularia and
Campanula ] : Botanical Gazette, Vol. IX, October and November,
1884, p. 176.
1885.
How the pitcher plant got its leaves: Am. Naturalist, Vol. XIX,
June, 1885, pp. 567-578; with 11 figures.
Affinities of the genus Dionaea, Ellis; Jour. Cincinnati Soc. Nat.
Hist., Vol. VIII, July, 1885, pp. 111-114.
Progress of vegetation in the Ohio Valley: Jour. Cincinnati Soc.
Nat. Hist., Vol. VIII, July, 1885, PP- nS-iiQ-
An abnormal Rudbeckia: Science, Vol. VI, August, 1885, p. 103;
with fig.
1886.
The Hickory-nuts of North America: Pop. Sci. Monthly, Vol.
XXX, Nov. 1886, pp. 70-78.
1887.
The milkweeds: Am. Naturalist, Vol. XXI, July, 1887, pp. 605-615.
1888.
Diseased plums: Botanical Gazette, Vol. XIII, July, 1888, p. 193.
New variety of Asclepias tuberosa [var. flexuosa] : Botanical Ga-
zette, Vol. XIII, October, 1888, p. 271.
Notes on the development of Corynites Curtissii: Bull. Torrey Bot.
Club, Vol. XV, December, 1888, pp. 314-315; plate.
1889.
Distribution of Vernonia in the United States: Jour. Cincinnati
Soc. Nat. Hist, Vol. XI, January, 1889, pp. 136-140.
Remarks upon Color as a distinguishing feature of certain species
of plants: Bull. Torrey Bot. Club, Vol. XVI, October, 1889, pp.
268-270.
1890.
Leaves of Liriodendron (A notice): Vick's ^lonthly Magazine,
Vol. XIII, December, 1890, pp. 385-386.
1891.
Pollen: Its development and use: Pop. Sci. Monthly, Vol. XXXIX,
July, 1891, pp. zy7-ZAZ\ with 12 figures.
1892.
Electricity in horticulture: Sci. Am. Supplement, Vol. XXXIII,
No. 841, February 18, 1892, pp. I3435-I3436.
Recent work on plant diseases by the Department of Agriculture:
Science, Vol. XIX, 1892, p. 113.
10 The American Geologist, January, i898
Spraying for the prevention of plant diseases: Sci. Am. Supple-
ment, Vol. XXXIII, No. 8S3, May 7, 1892, pp. 136?!;- 13636.
Wheat rust and smut: Science, Vol. XX, -^ugust, 1892, pp. 93-94.
1893.
Black Rot of the Grape and how to treat it: Sci. Am. Supplement,
Vol. XXXV, No. 89s, February 25, 1893, p. 14307.
Esparto Grass: Sci. American, February 25, 1893, p. 115.
The largest trees in the world: Science, Vol. XXI, March, 1893,
p. 123; also Sci. Am. Suplement, April 8, 1893.
Notes on fossil fungi: Jour. Mycology, Vol. VII, May, 1893, pp.
268-273.
Index to [Mycological] Literature, notices of papers on Mycology:
Jour. Mycology, Vol. VII, pp. 292-311. Scattered on various pages.
1894.
Fungi and insects: Science, Vol. XXIII, Jan. 1894, pp. 52-53.
Man's work in defense of plants: Sci. Am. Supplement, Nos. 996,
997, July 7 and 14, 1894, PP- I5442-I5444, I5456-IS4S7; with 5 figures.
Index to [Mycological] Literature: Jour. Mycology, Vol. VII,
August, 1894, PP- 400-430. Scattered.
1895.
Remarks on some recent fungi exsiccati: Science, new series, Vol.
II, November, 1895, pp. 654-656.
*
Miscellaneous,
1881.
The reasoning faculty of animals: Am. Naturalist, Vol. XV,
August, 1881, pp. 604-615.
1882.
The Colorado desert: Pop. Sci. Monthly, Vol. XX, January, 1882,
pp. 384-390.
Charles Robert Darwin: Jour. Cincinnati Soc. Nat. Hist., Vol. V,
July, 1882, pp. 71-77.
1883.
A prehistoric cemetery: Pop. Sci. Monthly, Vol. XXII, February,
1883, pp. 445-458.
1885.
Catalogue of the specimens in the Collection of the Cincinnati
Society of Natural History: Jour. Cincinnati Soc. Nat. Hist, Vol
VIII, April, 1885, pp. 31-48.
On the tracks of insects resembling the impressions of plants.
[Translated from the French of M. R. Zeiller] : Jour. Cincinnati Soc.
Nat. Hist., Vol. VIII, April, 1885, pp. 49-52.
Catalogue of the books and pamphlets in the Library of the Cincin-
«
nati Society of Natural History: Jour. Cincinnati Soc. Nat. Hist., Vol.
VIII, October, 1885, January, 1886, pp. 179-229.
Joseph Francis James, — Gilbert, 1 1
The English sparrow: Science, Vol. VI, December, 1885, pp.
497-498.
1886-1887.
Catalogue of the Mammals, Birds, Reptiles, Batrachians and Fishes
in the collection of the Cincinnati Society of Natural History: Jour.
Cincinnati Soc. Nat. Hist., Vol. IX, April, 1886, pp. 47-64; Vol. X,
April, 1887, pp. 34-48.
The Antarctic Ocean: Pop. Sci. Monthly, Vol. XXIX, September,
i886, pp. 660-666.
"Thumb-marks": Science, Vol. VIII, September, 1886, p. 212.
Papers on the destruction of native birds. Seventh Paper: Jour.
Cincinnati Soc. Nat. Hist., Vol. IX, October, 1886, pp. 219-220.
1887.
The Chinese Wall: Science, Vol. X, December, 1887, p. 323.
1888.
Index to the Journal of the Cincinnati Society of Natural History,
Vol. I to X inclusive. Including index to Part One of the "Proceed-
ings'* of the Society: Jour. Cincinnati Soc. Nat. Hist., Vol. XI, April,
1888, 33 pages.
Remarks on the Journal of the Cincinnati Society of Natural His-
tory: Jour. Cincinnati Soc. Nat. Hist., Vol. XI, April, 1888, pp. yd.
1889-1891.
Notes upon papers read before the Biological Society of Washing-
ton, D. C. : Am. Naturalist, Vol. XXIII, January, 1889, pp. 51, 52, 59,
61, 65; Vol. XXIV, November, 1890, pp. 1 103- 1 105; December, 1890,
pp. 1220-1224; Vol. XXV, January, 1891, pp. 88-90; March, 1891, pp.
298-299; April, 1891, pp. 400-403.
1889.
The great deserts of the earth : Sci. Am. Supplement, No. 703, June,
1889, pp. 1 1 224- 1 1 226.
EflFect of rain on earthworms: Am. Naturalist, Vol. XXIII, August,
1889, pp. 687-689.
1891.
Prehistoric man and the horse in North America: Sci. American,
Vol. LXV, September, 1891, p. 161.
1893.
The Scientific Alliance of New York: Science, Vol. XXII, Augiist,
1893, p. 66.
The American Association for the Advancement of Science:
Science, Vol. XXII, August, 1893, pp. 104-105.
1895.
Blood examination in disease: Science, New Series, Vol. II, Sep-
tember, 1895, pp. 412-413.
1-2 The Afnefican Geologist, January, i898
THE DETERMINATION OF THE FELDSPARS.
By N. H. WiNCHKLL, Minneapolis.
C'est par des efforts de co srenre que nos mdthodes microfirraphiques flniront par
conqu6rir la place qui leur est due dans les pro^rrammes universitaires at dans Ten-
sciffnement des grandes ^oiQs.—Fouqui.
C'est un devoir pour tout p6trographe qui se livre h une 6tudo nouvelle de s'ing6-
nier pour amender et porfectionner los proc6d6s do reciierche quo lui donne la sci-
ence coutempornine.— i^ougti^.
La determination precise, rapide et relativement facile de tous les 6l6ment8
foldspathiques des roches est une des conditions indispensable h r^tablissement d'une
classification rationelle.— Jl/tc^Z-JWfy.
On pent en quelque sorte jauger la valeur d'une 6tude petrograpliique au soin
apport6 par I'auteur li determiner les feidspaths de sos plaques m'mceH.— Michel -
L4vy,
Introduction.
Owing to the prevalence of the feldspars in nearly all crys-
talline rocks their accurate determination is one of the essen-
tials in practical petrography. As they appertain to the mono-
clinic and the triclinic systems, their investigation involves
most of the problems which arise in the use of the petrograph-
ical microscope. Hence, as has been remarked by Michel-
Levy* the progress of accurate methods of their determina-
tion has been the touchstone of progress in microscopical
petrography. This progress is due to the skill of several petro-
^'raphers — Descloiseaux, Fouque, Michel-Levy, Schuster,
Fedcrov and others.
The following sketch consists of a presentation chiefly of
the methods which have been devised within recent years in
♦Determination des feidspaths dans les plaques minces, 1894, p. 2.
Determination of the Feldspars, — WiJichell, 13
France, due to the genius of MM. Fouque and Michel-Levy,
whose remarkable contributions have attracted the attention
of every petrographer.* They not only embody, in the latest
advanced form, the results of all earlier petrographers, but
they extend the means of determination to greater scope and
j^reater refinement.f If it shall serve to call the attention of
American petrographers, now under the dominance of the
German school, to the excellence of the French methods, the
object of this sketch will be accomplished.
Preparatory to this it is necessary to recall briefly the prin-
cipal characters of the feldspars.
♦Following are the titles of the original publications to which refer-
ence is made above:
Michel-L^vy : —
De Temploi du microscope polarisant a lumiere parallel pour I'etude
des plaques minces des roches eruptives. Ann. d. Mines, Dec. 1877.
Mesure du pouvoir birefringent et positions d'egale intensite lumi-
neuse des mineraux en plaque mince, 1884. Bui. Soc. Min. France.
Mineraux des roches (with A. Lacroix), 1888, Baudry & Cie., Paris.
Sur les moyens: (i) de reconnaitre les sections paralleles a g' (010)
des feldspaths dans les plaques minces; (2) d'en utiliser les proprietes
optiques. Comptes Rendus des Seances de I'Academie des Sciences,
t. CXI., p. 700, 1890.
Etudes sur les roches des Puys et du Mont-Dore. Bui. Soc. Geol.
France, Reunion extraordinaire a Clermont-Ferrand, 1890, p. 674 et
suiv. Plusieurs Contributions.
Etudes sur la determination des feldspaths dans les plaques minces
au point de vue de la classification des roches. Baudry & Cie., Paris,
1894, p. 171. 8 planches.
Ditto :—
Deuxieme fascicule. Sur I'eclairement commun des plagioclases
zones: Proprietes optiques de microcline. Baudry & Cie., Paris, 1896.
Fouqui :-
Mineralogie micrographique. Roches eruptives fran^aises (avec
Michel-LevyX Mem. de la carte geol. de France. Ministere des Tra-
vaux publiques. Paris, 1879.
Contribution a Tetude des feldspaths des roches volcaniques. Bui.
. Soc. Min. Fran., 1894.
Lacroix : -
Lastly, these principles and methods have been extensively applied
by Prof. A. Lacroix in his late works: Les enclaves des roches vol-
caniques (Ann. Acad. Macon, vol. X, 1893), and Mineralogie dela
France et de ses colonies (Paris: Baudry & Co., 1893-6); where will also
be found a large number of new optic properties of the various minerals,
many of them pertaining to the feldspars.
tThe writer is under great obligation to Messrs. Michel-Levy.
Fouque and Lacroix for assistance and critical suggestions in the prepa-
ration of this sketch, and to Dr. U. S. Grant in its revision.
14 The American Geologist. Jannary, i89k
General Characters of the Feldspars.
The feldspars are all closely related as to form, and their
chemical composition varies from one to the other according
to the prevalence of the alkaline bases. They are silicates of
alumina with an alkaline base, and hence are colorless.
Forms of the Feldspars,
Orthoclase, microcline and anorthoclase may be associated
in one group on account of their near identity of form and the
similarity of their bases. Orthoclase is monoclinic*, and anor-
thoclase scarcely varies from monoclinic. Figures i, 2 and 3
represent common, simple forms of orthoclase. The angle
001 A 010 is 90°. In anorthoclase it is practically 90°. In
the upper positive quadrant of the crystal it is a little more
and on the negative quadrant a little less than 90°. In the
lower right quadrant it is less and in the lower left quadrant it
is more than 90". In microcline and anorthoclase, therefore,
as with the plagioclases, the basal plane of the crystal in its
conventional position, i. e., with the vertical axis(r) perpen-
dicular, tips not only forward toward the observer, but slightly
toward the right. The angle 001 A 100 is 116° 7' in ortho-
clase and microcline, and ii6°22' in anorthoclase.
Orthoclase is frequently elongated in the plane of sym-
metry, that is, parallel to the face 010, in the direction of the
horizontal axis (a), the crystals then taking the forms of quad-
ratic prisms, the real prism faces 1 10 and 1 10 being reduced to
comparatively insignificant dimensions (fig. 3). Anorthoclase
is often elongated parallel to the edge 110:110.
The plagioclases are distinctly triclinic, yet the angle ^r
does not depart far from 90°. Their forms therefore are quite
near that of orthoclase. The obtuse angle a (ooi A 010)
in the plagioclases is as follows: albite, 93^36'; oligoclase,
93°5o'; andesine, 93°(?); labradorite, 93°2o'; anorthite, 94*" 10'.
By the development of the faces 001 and 010 they are sub-
jected to the same elongation as orthoclase (fig. 3), and in
addition they are sometimes elongated parallel to the edge
001:100. This elongation produces the variety pericline of
albite (fig. 15), and when twinned gives rise to pericline stria-
tions which appear in all the plagioclases on 100 and 010.
♦According to Mallard orthoclase is triclinic.
Determination of the Feldspars, — Winchell.
15
lio
110
Fio. 1.
Fio. 2.
Simple Forms of Orthoclase.
Fio. 3.
Cleavages.
The feldspars all possess an easy cleavage parallel to the
base (001) and another less evident parallel to the pinacoid
010. There are also rudimentary, often irregular, and coarser
cleavages parallel to the prism faces no and no, etc. The
basal cleavage is always visible if the thin section be not too
thick, nor parallel to the base. That parallel to 010 is parallel
to the albite striations, and disappears in sections cut parallel
to 010. In orthoclase these cleavages form a right angle with
each other. In all the other feldspars they are oblique. These
cleavages are best observed in sections rather thin, and on low-
ering the condenser.
Twinning.
The feldspars are all subject to twinning*. Orthoclase is
especially frequent in the form of Carlsbad twins, but also
shows the forms of Manebach (Four-la-Brouque) and Baveno
(figs. 4, 5 and 6).
The Manebach type (fig. 4) has the basal plane as composi-
tion face, and the axis about which the crystal turns is a line
perpendicular to the base 001 (Lacroix). The cleavages 001,
of one twin, are parallel to those of 001 of the other. The same
is true of the cleavages 010. But their extinctions have oppo-
site signs, only one of the twins being in the conventional po-
sition (p. 14).
In the Carlsbad form the twins are united by some plane,
usually 010, parallel to the vertical axis (fig. 5). One is turned
180° from the position of the other about the common vertical
axis. In a thin section of a Carlsbad twin the pinacoidal
*The French word "made" might appropriately and conveniently be
substituted for the word twinning. "^
i6
The American Geologist.
January, 189H
Fio. 4.— Manobacli.
Fig. 5.— Carlsbad.
Fro. 0.— Bavom>.
cleavage (oio) in one twin is parallel with that in the other,
and unless the section be cut in a zone whose axis is either par-
allel or perpendicular to the face oio, the different cleavages
all form oblique angles with one another. If a section be in a
zone whose axis is either parallel or perpendicular to the face
OIO, the cleavages will stand at right angles.
In the Baveno twin the plane of association is the clino-
dome 02I. Sections cutting such a twinned crystal present
square or rhombic outlines, the cleavages being parallel to the
sides. The line separating the twins runs diagonally, from
corner to corner, as seen in figures 7 and 8. These sections
are not uncommon, since in the case of the Baveno-twinned
crystals they are also usually elongated parallel to the edge
001:010.
001
010
010
Bavouo twins in thin ^»(»ction,
Fig. 7.— Perijendicular section. Fig. S.— Oblique si'Ctiuu.
The basal faces and the brachypinacoids which form the
surfaces of the prism are at right angles to each other.
While these forms prevail in the monoclinic feldspars it is
not uncommon that they unite, in the triclinic feldspars, with
the albite and pericline types of twinning, which are rarely
absent in the latter.
Albite and Pericline Tzvinning. — All the plagioclastic feld-
spars are characterized by fine polysynthetic twinning, which
Determination of the Feldspars. — Wi?ichell,
17
Fio. 7a. Fio. 8a.
Albite-Twinned Foldspathic Microlitos.
produces a fine superficial striation visible to the naked eye;
it is caused by a succession of changes in direction of growth
of the crystal, each layer being turned from its fellow preced-
ing by an angle of about 172°. When the twinning axis is a
normal to 010, this twinning forms the albite type. When it is
parallel to b it forms the pericline type. In the albite type the
lamellae are parallel to 010 and produce striations on the sides
001 and 100. They are not visible in thin sections parallel
to 010, but in all others they are apparent in narrow bands
which polarize and extinguish alternately, on being rotated
between crossed nicols, the colored bands being parallel to
the pinacoidal cleavage. The external pericline striations are
visible on all faces of the crystal. If striations appear on the face
010, they are necessarily of the pericline type. In thin sections,
if the pericline twinning exists, it is visible in sections cut in
all directions except parallel to the composition face, and in
andesine this face is practically parallel to the base 001. In
the other plagioclases it is in the same zone, but makes an
angle with the base (fig. 16.)
Figures 7a and 8a represent each a pair of microlitic twins
of the albite type, the former having an elongation parallel to
the axis a and the latter a flattening parallel to 010.
Figure 9 represents a triclinic feldspar included between
the principal crystal faces 001, 100 and 010. The lines which
cross each other on the faces 001 and 100 indicate the external
striations due to the albite and pericline types of polysynthetic
twinning; those that appear on the face 010 represent the ex-
ternal striations due to pericline twinning. In the various
plagioclases the latter make different angles with the basal
The American Geo
cleavage or with the edge 001:010. In albite it is about as
shown in the figure, viz.. 13° to 22°; in oligoclase it is 4'; in
andesine it is 0° ; in labradorite from 2° to 9° in the opposite
direction, and for anorthite it is 18° in the same direction as
for labradorite (fij;. 16.)
When the polysynthetic twinning, albite or periciinc, is
again enveloped by a Carlsbad twinning, a thin section mani-
fests it by the occurrence of two pairs of bands on one side
which extinguish or polarize in sympathetic alternation, differ-
ently from two pairs of bands on the other side. Generally
the darkened line which separates the Carlsbads can be seen.
It is heavier than the other dark lines, and is apt not to agree
with them strictly in direction, or to be otherwise irregular.
The twinning of anorthociase and microcline is character-
istic. They combine the albite and pericline types, producing
a rectangular quadrillage on all sections of the zone 001:100,
except on that which is parallel to the plane of association for
the pericline law, and on all sections in the zone 001 :oio ex-
cept on that parallel to the face of association for the albite
law. In other words, the section parallel to 010 is identified
by the disappearance of the albite made and that parallel to
the plane of association of the pericline made by the disap-
pearance of the pericline marks. This last plane in anortho-
ciase, shown by the trace of its made, makes an angle of — 78°
to — 75° with the edge 001 :oio. It hence makes a large angle
with the base 001, and it is practically perpendicular to the
Detirmination of the Feldipars. — Winchell.
Fig. 12.-qundrillaB0of Microclino.
face oio. In microcline this plane, while nearly perpendicular
to ooi, and quite peq>endicular to oio, has a trace on oio
which forms an angle of — 80° to + 100° with the edge
AlbiW TwioB of Labrailorilc.
OOI :oio (fig. 16). Its position is between the faces roo and
201. The cross-hatching of microcline is represented by fig.
12. That of anorthoclase is less distinct, being extremely fine
and badly defined.
FIO. l!.-PflriclineTwiu,"of Albilfl.
With the plagioclases, properly so called, the albite and
periclinic types of twinning play an important role (figs. 13,
14, 15). They are adopted as characteristic and permanent
standards from which are measured other optic phei
20
The American Geologist,
January, 1898
The striations of the pericline made, when visible in a section
parallel to oio, make different angles with the basal cleavages
which are visible in the same section, according to the feldspar
examined. This angle varies from o** for andesine, to — 18**
for anorthite, in one direction and in the other direction it
varies to + 13° and +21** for albite. It may be represented
for all the triclinic feldspars by the diagram below (fig. 16),
which shows the face 010 of a simple crystal. '
- ^^*An/orihXis
-o«"
100
9 1
KLdhradorUe
•.2* J
74* t« - rfAnorthoclase
"^^'^"^."^ ]merocUne
Fig. 16.— Angles of the Pericline Bands on 010.
The plagioclases are also subject to twinning on the Carls-
bad, Manebach and Baveno plans, and albite also on the Roc
Toume plan. This last consists of two albite macles, again
twinned as couples by the union of the reentrant angle formed
by the faces loi, loi, of one, upon the salient angle of the
other formed by the same faces. The double crystal thus
formed is approximately a parallelogram, flattened parallel to
oio, one of the twinned pairs being thinner than the other,
as shown by figure 17.
In thin section the twinning lines of albite are fine and far
apart, often irregular and interrupted; those of oligoclase
are very clear and of very regular widths, one of the
systems being much more fine than the other — so
fine, indeed, that sometimes it is impossible to perceive
the width. In labradoiite the lamellae are equally
clear and definite, but the width varies much from one
lamella to the other, and in the same lamella (rarely)
from one point to another. In anorthite the albite lamellae are
Determination of the Feldspars, — WinchelL
21
broad and regular, while those of pericline are very frequently
distributed only in certain ones of the albite bands, which they
cross at varying angles according to the direction of the plate.
Figure i8 represents a triclinic feldspar crystal with the
Fig. 17.— Made of Roc Toarn6 (Descloizeauz).
albite and pericline striations much amplified, to show their
positions and direction for the species albite. The front face,
loo, is represented in part, but it is very rarely seen in nature.
The prism planes, i lo, i lo, obliterate it.
Chemical Composition.
According to the law of Tschermak, which is generally
adopted as a working hypothesis, at least, the plagioclase feld-
spars contain such proportions of soda and lime that each can
be considered as a mixture of a definite number of the com-
pound molecules Ab and An, in which —
One albite molecule Ab= NagO. AljO,. 6 SiO.^. or Na
AlSigOg.
One anorthite molecule ^^ An CaO. Al^Og. 2Si02. or
Ca AljSijOg.
Thus the basicity grades from albite to anorthite in a some-
what regular series.
Tschermak groups them ds follows:*
Albite
Oligoclase..
Andesine . . .
Labradorite
Bytownite . .
Anorthite . . .
Specific
Gravity
2.62
2.64
2.65
2.69
2.71
2.75
Compound
Molecules.
AbeAni
AbaAn2
Ab,An,
AbiAn,
Ab,An,
to AbsAni
to Ab2Ani
to Ab4An3
to AbiAnz
to AbiAne
to AboAa,
Percentage
of Ab
100.00 to 88.88
85.71 to 66.66
60.40 to 57.14
Percentage
of An
0.00 to I I.I I
14.28 to 33.33
40.00 to 42.86
50.00 to 33.33' 50.00 to 66.66
25.00 to 14.28,75.10 to 85.71
I I.I I to 0.0088.88 to 100.00
*Mineraux des Roches, p. 196.
26
The American Geologist,
January. 1888
more varied. It is represented in figure 24 as projected on a
plane perpendicular to the edge 001 : 010, the bisectrix «p ,
being perpendicular or at least less inclined to the surface of
the projection than % , and n^ lying approximately in the
paper. From this it appears that from albite to anorthite there
is a gradual rotation of the optic plane in a direction opposite
to the movement of the hands of a watch about a line parallel
(or nearly parallel) to ;in, and that the whole movement
p»
amounts to somewhat less than three-fourths of an entire revo-
lution.
ptr.tooto
Fig. 24.— Projection of the principal indices of the triclinic feldspars upon a
plane x)erpendicular to 001 : 010. 1, Albite : 2, Oli^roclase ; 3, Andosine
4, Labradorite ; 5, Anorthite.
The optic plane is represented in figure 25 as projected on
the face 010. From this it appears that its projection rotates
in a similar manner, from this point of view, about a line
nearly parallel to n^. The axis of least elasticity (wg) of all
the plagioclases is situated nearly in the plane perpendicular to
the edge 001 : 010, while the axis of greatest elasticity, n^ , is
nearly parallel to that edge, and in the plane of symmetry.*
The value of the acute optic angle (2 V), in the various
feldspars, and their optical signs, are shown in the following
table:
♦There is no zone of symmetry in the triclinic feldspars; but for con-
venience of reference the zone perpendiculai; to the edge 001:010 is
called the zone of symmetry in the discussion of the plagioclases.
Determifuition of the Feldspars. — WinchelL
27
Orthoclase
Microciine
Anorthoclase
Albite
Oligoclase
Andesine
Labradorite . .
Anorthite
2V
77
69^
88«
88^
770
°3o:
2E
119° to 125'
65^ to 75«
155"
2H
88«
80^ to 85^
90«
90^ to 100^
85° to 89°
85^
Sign
+
±
+
Refraction aTtd Double Refraction, ^
The feldspars all possess low refraction and double refrac-
tion, both being about the same as for quartz. By these char-
acters, therefore, it is sometimes difficult to distinguish them,
when pure, from quartz. When other diagnostics are not
available resort may be had to the Becke method of distinc-
tionf of comparative refraction. This consists in the follow-
ing very delicate process:
FUou normal
Fig. 25.— Projection of the principal indices of Albite (n^ ), Oliffoclase (n^ )
Andesine (n^ ), Labradorite (n^ ),and Anorthite (n^ ). on the plane 010.
*The values of 2 V from microciine to anorthite inclusive are taken
from Fouque, Bui. M. Soc. France, 1894, p. 428.
tUber die Bestimmbarkeit der Gesteinsgemengtheile auf Grund
ihres Lichtbrechungs Vermogens. Wien. Acad., 1893, I.
28
The American Geologist,
January, 18Ks
In convergent light with a high power (Nachet No. 7 ob-
jective), bring the focus directly upon the line of separation
between a quartz grain and a feldspar. On lowering the con-
denser and removing the analyzing nicol the field is a little
darkened, but a very fine line of white light, clearer and
brighter than the grain on either side, accompanies sharply
the line marking the contact of the two grains. When the
objective is focused so that the line is bright, if the objective
be raised very gently, and the least amount possible, this
bright line moves a little toward the more refractive mineral
before it is extinguished. If the objective be lowered in the
same way the white border line shifts a little toward the less
refractive mineral. This method is most useful for distin-
guishing between orthoclase and quartz and between the fresh
secondary plagioclases of the crystalline schists and quartz.
The other feldspars are usually distinguishable by other char-
acters. It is to be employed with one condition, viz: when
two adjacent minerals of nearly the same refractive index
happen to be cut, one perpendicular to //p and the other to n^ ,
the movement of the line might be governed by the difference
between n^ and % of the minerals, rather than by the differ-
ence of their mean refractive indices.
The table below shows the indices of refraction and the
double refraction of the feldspars as given by Levy and La-
croix (Min. des Roches, p. 323) :
Orthoclase ..
Microcline . .
Anorthoclase
Albite
Oligoclase . . .
Andesine . . .
Labradorite .
Anortbite ...
Quartz
Refraction
•
Double
Refraction.
^
^m
«P
//^-/?p
1.526
1.523
1. 519
o.cx)7
1.529
1.526
1.523
0.006
1-530
1.529
1.523
0.007
1.540
1.534
'•532
0.008
1.542
1.538
1.534
0.008
1.556
1-553
1-549
0.007
1.562
1.557
1-554
0.008
1.566
1 0.013
0.009
i
1-553
1.544
Determination of the Feldspars. — Winchcll. 29
Methods of Determination.
{a) Extitution on the Base and Brachypitutcoid,
Schuster and Mallard* established the relations existing
between the extinction angles on the base and the brachypina-
coid, and the changing acidity of the plagioclases. The preva-
lence of favorable cleavages renders it a simple matter to
obtain plates parallel to these faces. For purposes of deter-
mination it is usually necessary only to make a coarse powder
from one of the crystals, from which may be selected such
cleavage fragments as affords these two directions. These
may be distinguished not only by the difference in the facility
of the cleavage, but also by the different interference figures
given in convergent light. Cleavage pieces parallel to 001 will
appear larger and more abundant than those parallel to 010.
They will be apt to show some trace of the albite striations,
and they will never show a bisectrix, but instead will exhibit
the indefinite extinction characteristic of Wm. Anorthite
comes nearest to exhibiting a bisectrix in a basal section. On
the contrary cleavage fragments parallel to 010 are likely to
have two straight parallel edges, caused by the easy basal
cleavage. These, however, should not be confounded with the
basal fragments bounded by the prismatic cleavages. At the
same time if the fragments be parallel to 010 they invariably
reveal a bisectrix «g, either perpendicular or somewhat in-
clined to the axis of the microscope when examined in con-
vergent light. To this statement labradorite (from Abi Ani to
Abi Ana) may be considered an exception, inasmuch as the
inclination of the axis ( fif^) is so great that the point at which
it pierces the plane of the section is outside the field of the
microscope. It may still be distinguished from a basal section
which gives the same black bar by the application of the
quartz of sensitive tint, which shows the lowering of color
characteristic of the bisectrix w^ although not so decidedly
as when the axis is exactly perpendicular. In a similar man-
ner the black bar seen in labradorite in a basal section may
be shown to be associated with «p . The basal section of
*Uber die optische Orientirung der Plagioclase. Min. u. Petro-
graph. Mitt, Tschermak, 1880, III, 117-284.
Sur risomorphisme des feldspaths tricliniques. Bui. Soc. Min.,
Frartce, 1881, IV, p. 103.
/
30
The American Geologist.
January, 1898
anorthite shows the black bar associated with n^. Compare
also the page following — "Means of discovering sections par-
allel to oio."
When the examination has to do with the microlitic feld-
spars of the second consolidation, it is usually impossible to
obtain cleavage fragments for the foregoing process. It is
then necessary to search for favorable sections cut at random
in a thin section of the rock, when the same distinctions are to
be observed, or resort may be had to the methods mentioned
below. Sections parallel to oio do not show the albite twin-
ning lines.
In general, when the extinction angles on both ooi and
oio are large that fact indicates bytownite or anorthite. When
both are small the feldspar is either oligoclase or andesine.
Intermediate extinction angles are seen in albite and labrador-
ite; while the potash and soda-potash feldspars have extinction
on ooi practically parallel to the cleavages (except microcline,
which has extinction at 15** 30'), and on 010 their extinction
varies from 5** to 9**.
Following are the extinction angles of the feldspars on the
base and brachypinacoid :
Orthoclase . . .
Microcline. .
Anorthoclase
Albite
Oligoclase . .
Andesine . . .
Labradorite
Bytownite.. .
Anorthite . . .
Extinction on
CX)I.
+'
5^30'
—2^30 '
-5«30 '
-15*^ to - 25'
-36^30 '
Extinction on
GIG.
+5° to t
+5° 30 '
20®
-26^ to
-41*^30'
-32«
{b) The Statistical Method*
The method proposed by Michel-Levy, often designated
the statistical method, is applicable to all cases in which cleav-
age pieces of sufficient size cannot be obtained, but in which
still the albite twinning is evident. Since the albite twinning
forms lamellae parallel to the face 010, whose edges are inclined
*De I'emplGi du microscope polarisant a lumiere parallel pour I'dtude
des plaques minces des roches eruptives. Ann. des Mines, Dec, 1877,
pp. 392 to 471 (v. p. 451).
Determination of the Feldspars, — WinchelL
31
to each other alternately outward and inward, a thin section
cutting these lamallae at right angles to 010 would cut them
also at right angles, and the extinction angles on opposite
sides of any twinning line would be equal, but of contrary
signs since, according to the law of albite twinning, one
lamalla is turned 180** from the conventional position about a
line perpendicular to 010. In case the section be not cut in
a plane perpendicular to 010 the extinction on one side of the
twinning line is greater than on the other. The method con-
sists in finding in some feldspar grain the maximum equal ex-
tinctions on opposite sides of an albite twinning line. All
sections that have equal extinctions on adjacent sides of a
twinning line in the same species are cut in the zone perpen-
dicular to the faces 010; but only one of these affords the
maximum equal extinction. The position of the plane which
affords the maximum extinctions in the zone perpendicular
to 010, is different for the different species, and the maxima
also differ for the different species. When this maximum has
been found it serves for the index to the species according to
the following tabulation. The table, drawn principally from
Maxi-
Compo-
sition.
mum
equal
Extinc-
tion.
Position of the Plane with respect
to the bisectrices.
( )rthoclase
Microrline
Anorthoclase . .
Or.
Or.
Ab,Or.
Ab
0^
+19°
Monoclinic.
Inclined (25° N. and 25° E.).
Albite
i6«
Perpendicular to «p in the obtuse
Oligoclase
Oligoclase
AbjAni
Ab4An,
+4"
angle.
Perpendicular to «p in the acute
angle.
Inclined 30'' on «m and 25*^ from
001, downward toward the front,
i. e. S.
Inclined 4^* E. and 4® N. from «p
in the acute angle.
Inclined 10^ E. and 15° N. from
«p in the acute angle.
Perpendicular to 201, i. e. inclined
18^ E and 22^ N. from «pin the
Andesine
Labradorite . . .
Labrador-
Bytownite . . .
AbaAns
Ab,An,
Ab3An4
-1-16°
-f-27-
4-38°
Anorthite
An
+52>^^
acute angle.
Inclined ISC'* N. from the optic
axis B, and 30*^ E. from «p in
the acute angle.
32 The American Geologist, January, i898
the epures of Michel-Levy,* also expresses the position of the
plane with respect to the bisectrices. The maximum extinc-
tion angles here given are found, for each feldspar, on the ver-
tical diameters in the plates I — VII.
In the application of this method it is not necessary to ex-
amine all sections of feldspars at random, but by certain guides
those in the zonal position can be selected, (i) It is the zone
of symmetry of the albite twinning, and the alternate lamellae
extinguish at the same angle. If account be taken of the
optical sign of the direction of extinction (+ to the right of
the twinning line and — to the left) the positions of other
planes, inclined to this zone may be identified by reference to
the epures of Michel- Levy (plates I — VII). f (2) The sections
of this zone, being perpendicular to the face of association of
both the albite and the Carlsbad twinning, the albite twinning
lines ought to be extremely fine and straight. Further the
feldspathic microlites, however small, cross the thin section
perpendicularly. They seem to be elongated parallel to these
lines; their outlines are clear and their colors of double refrac-
tion are those that comport with the total thickness of the
plaque for the orientation in each case. (3) Sections that are
perpendicular to 010 have not only equal extinction angles,
but they may be identified by the fact that the two lamellae
on opposite sides of the twinning line have, on rotation be-
tween crossed nicols eight positions of equal luminosity, viz:
four at 45° from the spider lines, one in each quadrant and
four at the points of agreement with the spider lines. In these
positions the lamellae appear to belong to the same crystal,
being separated only by a very fine dark line. This test is ex-
tremely delicate and with the least obliquity to the axis of
the zone the equal luminosity does not appear.
This method, notwithstanding its tediousness, is one of
the most serviceable as well as the most reliable, owing to the
readiness with which sections perpendicular to the plane 010
can be recognized, and to the characteristic differences in the
maxima of the various feldspars. The chief obstacles that
interfere with its use are (i) the possible existence of two or
♦Determination des feldspaths dans les plaques minces, first fascicule,
1894.
t For explanation of these plates see p. 40.
Determiftation of the Feldspars. — IVinchell. 33
more feldspars in the same thin section, and (2) the possible
non-existence of the maximum equal extinction in any of the
crystals cut by the random section. The former is more likely
to arise in the examination of the acid and metamorphic rocks,
and the latter in case of a limited number of feldspar sections
in the rock cut. In the presence of two or more feldspars,
however, usually they will be found to differ in transparency
or in mode of distribution, or in other evident optical charac-
ters, and the error can be obviated. In case of the feldspathic
microlites, they are almost invariably of the same species when
formed rapidly at the second consolidation. The second obsta-
cle can only be reduced by increasing the number of feldspar
sections subjected to inspection.
These maxima, alone, are sufficient to identify the oligo-
clases (0° to 5*), the basic andesines (more than 16°, less than
22°), the labradorites (from 22° to 35°), the bytownites (from
35° to 45°), and the anorthites (above 45°).
When the feldspar microlites are twinned on the albite
plan, as frequently happens, they are amenable to this process
of examination. When they are simple their determination
is more difficult. It has been proposed by Michel-Levy, in
that case, to employ the zone 001 :oio parallel to the axis of
which they have their longest dimension, but the results ob-
tained are not sufficiently characteristic for all the species.
Extinctions of such microlites, cut in this zone and referred to
their longer dimension, are as follows:
Orthoclase o** to 5*
Microcline o** to 16'
Albite o** to 20*
Oligoclase Ab4 Am 0° to ^
Oligoclase Ab« Am o** to o*
Andesine 0° to 7**
Labradorite 0° to 18*
Labradorite (basic) .... o** to 32*
Anorthite o** to 55'
Microcline, some forms of labradorite and albite could
hardly be distinguished by their maximum extinctions in
simple microlites, but orthoclase, oligoclase and anorthite are
characterized by maxima which are sufficiently distinct.
Microcline, however, is rarely or never seen in the condition
of microlites, while the associations of labradorite and albite
.0 >
• Compare p. 43.
34 The American Geologist, January, i8«j
are so different that there is little danger of confounding them.
Labradorite is the commonest product of the consolidation
of the basic eruptives and albite almost invariably results from
metamorphism, frequently from the contact of igneous rocks
on the calcareous elastics.
There is very little reason to expect, side by side, micro-
lites of different natures. In the vast majority of cases the
microlites are formed rapidly, and present a great preponder-
ance of a single species of plagioclase.
(r) Sections Perpendicular to the Bisectrices,
This method of determination requires the use of con-
vergent light and the careful observation of the interference
figure of the axis of elasticity. It is well, also, but not always
necessary, to place a drop of iodide of methyl, or of glycerine,
on the lens of the objective, and another on the upper lens of
the condenser, in order that when they are both brought near
the slide holding the section, the liquid will spread to the right
and left, producing practical immersion. This increases the
field of possible observation without deranging the geometric
relations.
JL he details of this method have recently been elaborated
by M. Fouque,* who has confirmed it by a great number of
illustrations, and by chemical analyses. It may at first sight
appear to be a difficult task to obtain sections perpendicular
to the bisectrices «^ or Wp. But when it is remembered that
cleavage pieces or sections cut parallel to oio will nearly
always show the axis ng , and when not perpendicular may be
made so by a little oblique grinding or by the use of the tilting
stage of Fed'erov constructed by Nachet, and also that the
axis «p is in the vicinity of the edge ooi : oio, it is evident
that but little manipulation is necessary to cut a crystal per-
pendicular to either axis. Small transparent crystals are neces-
sary, or pieces of larger crystals bounded by known cleavages.
The little crystal is encased in a ball of thick Canada balsam
which can be moulded at will. This is allowed to swim in a
Balsam more liquid, enveloped in a little glass ring. Observed
thus in convergent polarized light the crystal is brought to
♦Contribution k Tetude des feldspaths des roches volcaniques. Bui.
Soc. Min. France, Vol. XVII, 1894, pp. 283-611. Also issued sepa-
rately with independent paging.
Determifiation of the Feldspars. — Winchell. 35
present the orientation in which it gives the figure of the axis
sought. The operation is facilitated by the previous knowl-
edge of its cleavages, and of the probable nature of the species
in hand.
The axis «p is preferable in the examination of the acid
plagioclases, and n^ in that of the basic. M. Fouque ascer-
tained by the examination of numerous inclined sections that,
in case of slight obliquity, the decentring of the image and
the consequent error in the result, is less in sections perpen-
dicular to «p than in those perpendicular to n^^ . He also
ascertained that the error is greater (except in the basic feld-
spars) when the inclination is in the direction of the trace ot
the plane of the optic axes than in a direction perpendicular
to it. An inclination of 5* removes the figure one-third of
the radius of the field of the microscope away from the central
position. An inclination of 10° removes it two-thirds of the
same radius.
If a bisectrix is exposed favorably in the field of the micro-
scope, as frequently happens in a rock section cut at random,
it is important to know whether it is «p or //^ . Resort may
be had to the quartz of sensitive tint, which with the feldspars
in sections not over 0.03mm in thickness, is the most ready
and reliable test. It is also possible to know whether the axis
so examined is in the acute or the obtuse angle. After some
experience the observer becomes able to judge by the appear-
ance of the interference figure, and its changes on rotation of
the stage, in nearly all cases, whether the axial angle is acute
or obtuse. Thus, in the first place, the sections perpendicular
to ;ip are more dark in parallel polarized light than those per-
pendicular to % . This observation is frequently sufficient,
at least if the angle 2V does not exceed 80°. The delicacy
of the observation is increased by interposing a quartz plate
which g^ves the rose color of the first order of the color scale.
Again it is frequently possible to judge whether the axial angle
under examination is acute by noting the comparative amount
of rotation of the stage necessary to produce a marked separa-
tion of the hyperbolas. The promptly separating hyperbolas
belong to the obtuse angle. When the hyperbolas are tardy
in moving from the black cross the angle is acute. In case
such rough observation be not sufficient, the hyperbolas may
36 The American Geologist, January, i898
be brought to the position of tangency at the margin of the
field of the microscope, first on one bisectrix and then on the
other. In each case the amount of rotation is noted in degrees
at the margin of the platine. That which requires the greater
amount of rotation to produce tangency is the axis of the
acute angle. Finally, when there remains uncertainty whether
the angle is acute or obtuse, it may be measured by the use
of the axial goniometer already described in the American
Geologist.*
Once the interference figure is well centered and the angle
known, it remains to measure the extinction angle with a trace
•of a known crystallographic character. This angle is that
made by the axial plane with a twinning (albite) lamella, or
with the cleavage parallel to ooi. Sections perpendicular
to ;ip are always measured, for this angle, on the albite twin-
ning, or, which is the same thing, on the cleavage oio. In
the case of sections perpendicular to «g the same crystallo-
graphic character is employed in examining the basic feld-
spars, but it is necessary to have recourse to some other char-
acter for the acid feldspars in which the plane perpendicular to
;/g is parallel, or nearly parallel, to the face oio, rendering the
cleavage (oio) and the albite made invisible. In that case
extinction is measured on the cleavage parallel to ooi, which
is very rarely wanting in the acid feldspars. In all the lime-
soda feldspars, except albite and anorthite, the sections parallel
to OOI and oio, and perpendicular \o n^ , appertain practically
to the same zone. For these feldspars the extinction angle
upon a section perpendicular to n^ has therefore the same
value, whatever be the cleavage, that of ooi or that of oio,
which is chosen for the measurement of extinction.
The measurement having^ been taken, reference may be
made to the following table, 'given by M. Fouque as a sum-
mary statement of the results of all his work. The beginner
may be warned against the liability of misreading the extinc-
tion angle, thus getting the complement of the extinction angle
given in this table. In that case his error consists in measur-
ing, not from the trace of the axial plane, but from a line per-
pendicular to it. In other words — ^the axial plane, i. e., the
position of extinction, should be made to coincide with the
♦Op. cit., Vol. XVII, p. 79.
Detemiuiation of the Feldspars. — WinchelL 37
vertical thread of the nicol — not with the horizontal — and the
rotation from that position towards the right, necessary to
bring the cleavage or the albite made into agreement with the
same thread, is the angle of extinction desired.
Extinctions which range from 55° upward to 88** indicate
the bisectrix n^ Those which occur between 48** and 3*
indicate n^ perpendicular to the section.
(^) Sectiotis Perpendicular to the Axis of Mean Elasticity^ n^^.
M. de Federov has studied the extinctions in sections per-
pendicular to the axis Wm. They present the highest colors
between crossed nicols, and a somewhat characteristic figure in
convergent light.
As shown by the general epures they vary, from albite to
andesine inclusive, from +2° to — 2. They are not, therefore,
sufficiently characteristic to separate the acid andesines from
the albites. The basic feldspars, on the contrary, ranging
from — 2** (Andesine, Ab» An») to — 10° for labradorite, and
to — 36** for anorthite, are susceptible of distinction in these
sections. It appears, therefore, that very diverse methods suc-
ceed in this basic series and generally fail in the acid series.
Still the sections of maximum birefringence are capable of
rendering service, especially in the absence of twinning.
(^) Sections Perpendicular to the Optic Axes.
M. de Federov has also given the extinction angles. on the
optic axes in simple crystals (i'); and to these Michel-Levy
has added those of twinned crystals, both those of the Carls-
bad type and those of the albite. The numerals (i) and (i')
are made to represent the two individuals of the albite twinned
crystal, and (2) and (2') the two adjacent albite individuals of a '
Carlsbad-twinned crystal. It is evident that the parts (i) and
(i') belong to one or the other of the parts (2), (2'). The
following table gives the extinctions on the axis (A). Col-
umns (2) and (2') and column (i) are added by Michel-Levy.
The former shows the extinctions on the individuals (2) and
(2'), and the latter the angle of the plane of the optic axes with
the trace of the cleavage 010, which can easily be obtained
from the figure in convergent light.
38
The American GeologisL
January, 189^
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<
n3 b/
<
Determination of tlte Feldspars. — Winchell,
39
Albite
(^ligoclase (Ab«Aii,) . .
Oligoclase (Ab«An,)..
Andesine
Labradorite (AbjAm).
Anorthite
(0
A+62*=^
A 90^
A— 82^*
A— 7i«>
A-49«
A— 20**
(I')
+37"
0«(2)
— 40« (2)
-48^ (2)
-40^
-53^
(2)
o
--30
--25
--22'
--10^
-25<
(2')
+28°^ I)
-25^
+22**
+35^
+27"
+15-
Notes.
(i) Near the
axis B.
(2) Near the
axis A.
For the optic axis (B) the following table gives the same
elements. It is constructed in part from the numbers of the
general epures of Michel-Levy:
Albite
Oligoclase (Ab4An,)..
Oli^oclase (AbaAn,)..
Andesine
Labradorite (Ab.An,).
Anorthite
(I)
(I')
(2)
(2')
B+63»
+40"
+45°
-32°
B 90"
go" (I)
-35°
-25°
B 82"
-42° (I)
-17°
16°
B-69"
-31° (I)
— 6°
. 0°
3-57°
-2f
--3"
+47°
+14°
B-62«
—12° (2)
-56«
Remarks.
(i) Near the
axis A.
(2) Near the
axis B.
if) The Use of Zonal Sections,
Michel-Levy has investigated the principal crystallo-
graphic zones of the feldspars, and has deduced the charac-
teristic extinction angles in each. These zones are the fol-
lowing:
1. Zone perpendicular to 010.
2. Zone normal to the edge 100:010 situated in 010.
3. Zone parallel to 100:010.
4. Zone parallel to 001 :oio.
The examination of the zone perpendicular to 010 is al-
ready described under the Statistical Method, (p. 30). With
this as a basis Michel-Levy has constructed a series of very
ingenious and complicated tables, represented graphically in
the plates (epures) for the various plagioclases (plates I, II,
III, IV V, VI and VII). These circular plates show not only
the maximum equal extinctions of the simple crystal in each
plagioclase, when cut in a plane perpendicular to 010, but
also the extinctions of the same when cut in any zone whose
axis is in 010. The former is shown by the highest number
seen along the vertical diameter of each plate, and the latter
40 TIte American Geologist Jauaary, \m>
by the figures at the intersections of the meridians and the
parallels. Any line situated in oio may, hence, be taken as
the axis of a zone, and sections cut in that zone will show the
extinctions expressed on its principal meridian for the feldspar
considered.
These plates are stereographic projections of the sections
of the several plagioclases perpendicular to the prism. The
poles of the various planes of this prism are in the circumfer-
ence. The pole of the base (ooi) is not far from the center^
in the lower right-hand quadrant. The poles of some other
planes are also expressed. The entire surface is divided by
the meridians and parallels into quadrangular areas having
arcs of five degrees. The meridians running from right to
left all pass through the poles oio. The parallels which sur-
round the poles are the various stereographic positions of
planes inclined in different degrees to oio at intervals of 5**,
but in the zone whose axis is perpendicular to the vertical axis
c and parallel to 010. These elements are represented by
the fine black lines as meridians and parallels, and are the
same for all the plagioclases. The trace of the optic plane is
shown by the heavy black line passing through the loci of the
optic axes A and B and the bisectrices n^ and //p. The other
heavy lines show the planes connecting n^ with the bisec-
trices. About the axes of elasticity are double curves in brok-
en lines. These unite the poles having the same double re-
fraction. About the optic axes the first curve, shows the
double refraction 0.25. Then comes the curves of 0.35 to
0.85. This last surrounds the mean axis of elasticity ;/,n. At
the principal intersections of the meridians and the parallels
are figures which give, in degrees, the angles of extinction
for the planes whose poles are at those intersections. They
are counted from o** to 90° and are + on the right of the trace
010 (the albite line), and — on the left, as indicated. The ob-
server is supposed to be placed above the epure perpendicular
to each radius of the hemisphere, his body parallel to the trace
010; that is to say, to the parallels, his head higher than his
feet for the lower semicircle, but lower for the upper semi-
circle. The emergence of the optic axes is at A and B. The
axes of elasticity Wg , Wm and n^ pierce the great sphere at the
points expressed for each feldspar. They are united by great
Determination of the Feldspars, — WinchelL 41
circles in black which show the planes of principal elasticity.
The fine dotted lines unite poles of the same extinction angle.
The curves composed of crosses separate the negative from
the positive extinctions, and coincide with the curves of 0°
extinction.
The various planes of an inclined zonal axis contained in
the face 010 would find their poles arranged on an arc of a
great circle which would cross the plate along a meridian ex-
tending between the poles 010. The numbers that are seen
along this meridian denote the extinction angles for the dif-
ferent planes of such zone. The greater the inclination of the
zonal axis the greater the separation of its meridian from the
horizontal diameter of the epure.
These epures represent the projection and the optical char-
acters of simple crystals or lamellae in the conventional posi-
tion." In the case of polysynthetic albite twinning the extinc-
tion of every alternate lamella is of a negative sign, if read ac-
cording to Schuster's rule, but such negative reading would
not be that expressed on these epures. This change of sign is
owing to the rotation of the albite made 180° about an axis
perdendicular to 010. Again in the case of the Carlsbad twin-
ning in which there is a rotation of 180° about a line parallel
to the vertical crystallographic axis, it is evident that two in-
dividuals have contrary signs for the same reason. In the
case of both Carlsbad and albite twinning in the same com-
pound individual, only one albite lamella and its homologues
occupy the conventional position, although several may extin-
guish at the same point.
The zon£ normal to the edge 100:010 situated in 010 has
all its poles in the horizontal diameter of the epures already
referred to. The maximum extinction is always in the vicin-
ity of 010, and it increases regularly from a point near the
edge 100:010, as below. This zone is very characteristic for
the acid feldspars if the study is not carried to sections beyond
an inclination of 50" with the section perpendicular to the
prism. It affords a distinction between albite and andesine,
and also separates the oligoclases.
It appears, therefore, that the increments are continuous
from albite to anorthite, and this zone would be most charac-
42
The American Geologist
January, 1898
teristic and the most convenient if its sections could be found
easily.
Absolute
Maximum.
Extinction at 50^ from
100 : 010.
At the left.
At the right.
Albite.*.
6°
20°
K
90"
44°
+ I2«
+ 13°
+19"
-lYz"'
01igoclaseAb4Ani
OliffoclaseAbaAm
— 10»^°
Andesine Ab,An«
- 22 ^^^
Labradorite Abi An
^7©
Anorthite
—7(f
1 V
Zo?ie Parallel to 100:010. — This zone furnishes sections
which are not altogether conclusive, especially for the deter-
mination of the acid plagioclases, whose extinctions vary too
widely. It can be said, however, that in this zone the parts of
the Carlsbad twin extinguish symmetrically. The same is
true of the lamellae of the albite twinning. All its poles are
found in the exterior circle of the epures.
Zofie Parallel to the Edge 001:010, — ^This zone, parallel to
the two easy cleavages, is in constant application in the vario-
lytes, in arborescent forms of plagioclase, and in crystallites
formed rapidly. Such are, indeed, elongated parallel to
001 :oio. The normal alongement of orthoclase, when fibrous,
is parallel to 001:010, as shown by numerous spherulytes of
the orthophyres and of basic microgranulytes.*
The spherulytes of the plagioclases do not offer a single
known exception to the above rule. (Michel-Levy.)
The extinction numbers belonging to this zone are ranged
on the meridian which passes through the poles 001 and 010,
at about 26** below the plane perpendicular to the face 010
and to the edge 100:010. The following are in its numerical
properties: (p. 43).
There might arise uncertainty between the albites and the
most basic andesines. The smallest extinctions appertain to
the oHgoclases and the acid andesines. From labradorite
proper the maximum angle of extinction quickly exceeds the
maximum extinction applicable to the albites. It is worthy of
*"It is quite exceptional that Williams and Iddings have encoun-
tered spherulytes of orthoclase whose fibres are elongated parallel to
100:010."
Detertnination of tlu Feldspars. — Winchell.
43
Albite
Between ooi and the ob-
0^-20'^
Near oio.
•
tuse angle ooiAoio.
Oligoclase Ab^An, .
0°-^^
Between ooi and ooi
Aoio acute.
Oligodase AbjAn, .
oo-o'*
Andesine
Near ooi, between ooi
o«-7^
In oio.
*
and the obtuse angle
OOIAOIO.
Labradorite
Between ooi and ooi A
o«-i8"
Near oio.
Between
oio obtuse.
•
ooi and
acute.
ooi Aoio
Labradorite (basic)
Between ooi and ooi A
o°-32°
Near oio.
Between
010 obtuse.
ooi and
acute.
OOI Aoio
Anorthite
Between ooi and ooi A
o'-SS"
Near oio.
Between
010 obtuse.
OOI and
OOI Aoio
•
acute.
note that the zone ooi :oio always contains a plane nearly per-
pendicular to the bisectrix n^. Compare p. 33.
In making use of the crystallographic zones of the feld-
spars it is evident, therefore, that the zone perpendicular to
010 is the most reliable and has the widest application. When
the albite twinning line is visible it alone leads to characteristic
results by the shortest, most rapid and easiest way. The task
is facilitated and the distinction between albite and certain
andesines is assured, when several instances occur of the com-
bination of Carlsbad and albite twinning, which is very fre-
quently the case. The method of the positions of equal lumi-
nosity is a convenient means of searching out the different
groupings of the twinned lamellae, as well as the sections
properly oriented.
After the zone perpendicular to the brachypinacoid, which
is susceptible of universal and almost exclusive use with
microlites of small size, the zone 001 :oio affords similar ad-
vantages for every case of the variolytes and the porphyry tes,
or andesytes, in which plagioclase takes arborescent or spher-
ulitic forms.
The anorthites cannot be confounded with any other feld-
spar. As to the oligoclases, it should be remembered that
their properties are very near those of the anorthoclases. It is
convenient then to resort to the determination of the indices
of refraction, or to the measurement of the angle of the optic
axes, which in the anorthoclases is much smaller about the
acute negative bisectrix (p. 27).
44 The American Geologist January, 1898
{g) Means of Discovering Sections Parallel to oio*
(Compare p. 29, et suiv.)
The remarkable work of Max Schuster upon the plagio-
classes,f so happily completed by the theoretical application
by Mallard,J has brought to light what can be drawn from
the extinctions on any face whatever, provided its direction
can be determined.
From this point of view the face 010 is the most con-
venient, because it eliminates the albite twinning characters,
, and, further, it distributes the extinctions between numbers
sufficiently separated. The adjoining diagram (fig. 26) repro-
duces the curve of Max Schuster, and from that as a datum
adds the feldspars from the new epures (plates I- VI I).
In order to utilize§ extinctions in thin sections when the
feldspars appear scattered in a section cut at random, it is
necessary (i) to know how to recognize sections near 010,
and to judge approximately of the error committed by de-
fective orientation; (2) to be able to determine the obtuse
angle ooi A lOO.
I. a. The sections 010 being parallel to the face of the
association of the made of albite, the hemitropic lamellae
and their overlapping edges ought to widen out, and even to
disappear at last, at the same time that their extinctions be-
come the same; for the ellipse of the indicts returns upon itself
after a rotation of 180°. If in a section of the thickness of
0.02mm (e) the overlapping of the two lamellae reaches, for
example, a width (1) of 0.3mm, we should have evidently, call-
ing a the angle which 010 makes with the thin section.
tan a equals-y- equals ^0.^2. equals -^
a is less than 4°. We shall see later the error that
would be committed, from this, in the reading of the extinc-
tions.
b. The Carlsbad made has also for face of association
♦Translated from Michel-Levy. Deter, des Feldspaths, p. 46.
t Uber die optische Orientirung der Plagioclase, Tschermak. M.
P. Mittheil, 1880, III, 117.
X Sur risomorphisme des feldspaths tricliniques. But. Soc. Min.
de France, 1881, IV, 96.
§ Comptes Rendus, 10 Nov., 1890. Bui. Soc. Geol. France, 1890.
Reunion a Qermont-Ferrand, Etudes sur les roclies des Pays et du
^Tont Dore.
Determination of the Feldspars — Winc/uU.
45
«
5
Q) O
15*
I
s
4 20
-flO
-10
-20
.30
^hO
«
"^
N
\
(
Sr
•
>
kj
1
2
a»
N^
to
s
(0
7
8
10
^
^v>
s
Si
^
^
^)
"
,
^
9
s^
'>
Fig. 26.— Extinctions on 010 referred to the trace of the edge 001 : 010, positive, in the
obtuse angrleOOlAlOO, (Michel L6vy).
the face oio. It ought then to disappear in sections parallel
to oio, or, rather, it should only be visible by reason of the
superposition of two individuals of different optical orienta-
tion; for the ellipse of the indices is returned about the edge
looioio, and that of the twin takes a position in oio which is
symmetrical with respect to the direction of loo. In reality,
in the case of a Carlsbad twinning, contrary to that of albite
twinning, the junction of the twins is not a plane; there is a
reciprocal penetration which is often very irregular, and the
sections cut, although rigorously parallel to oio, very often
show two individuals adjoining and partly superposed — in a
word, penetrating each other along a line more or less sinuous
and irregular. When the traces of the easy cleavages (ooi)
46
The America?t Geologist.
January, 189S
are distinctly visible it is necessary that the angle between
them be about 128°, but that is a condition which is not suf-
ficient, and which only acquires a true value if the extinctions
of the same sign in the two twinned individuals occur sym-
metrically with respect to the bisectrix of the angle 128°.
There is then only one other plane in the zone 100:010 which
enjoys the same property. (Fig. 27.)
c. The faces which bound the supposed section parallel
to 010 can often be distinguished, sometimes by means of the
zones of increment, or growth, and sometimes by evident ex-
ternal contours. These faces are, in order of frequence, 001,,
201, 101, 1 10, 110, 201 and 203. The profile of their angles con-
stitutes a very good verification. Compare Fig. 28 for albite.
C.4»S1^
np
r-.
J11--X
Sy
W(i')
(2)(2')
1
FiQ. 27.— Carlsbad made visible ia 010.
Fig. 2^.— Face 010 in Albito.
d. Quite often the cleavage ooi is represented by fine
straight cracks, best visible in high powers and by lowering
the polarizer. Sometimes there is an excellent verification by
cracks more coarse and more visible which are parallel to the
cleavages of the prism no or no.
The discovery of the fine cracks (ooi) is facilitated by two
circumstances: They are always near the negative direction
/^p of extinction, since this last oscillates between +20** and
— 36**. They are often indicated by fine hemitropic lamella?
of the pericline twinning.
e. We have not mentioned, up to the present, this man-
ner of twinning, because, from an optical point of view, it
blends closely with the individual (lO (p. 37) of the albite law
of twinning; but it relieves all uncertainty as to the face of
association which is peculiar to it, for it may be said that, at
least for the oligoclases and the andesines, this face is almost
Determination of the Feldspars, — WinchelL 47
parallel to cx)i, and it has not appeared to me to depart sen-
sibly from it in labradorite (see Fig. 16). On the other hand,
the abundance of lamellae of the pericline type impairs the
diagnostic which might be drawn from the disappearance of
the albite lamellae, especially in anorthite in which the per-
icline made sometimes predominates over that of the albite.
In anorthite from St. Clement the face of association is about
— 15° from 001, in the zone 001:100, and in the acute angle
ooiAoio.
/. It remains to revert to the images seen in convergent
light. The bisectrix n^r is visible in the face 010 in albite,
oligoclase and andesine. The oligoclase of the second class
(Ab« Ani) gives a figure almost at the center of the field of the
microscope, with an extinction at + 6° in 010.
As the concentric zones of growth of the plagioclases very
often attain an acidity in a narrow belt at the periphery which
involves the centring of the figure seen in convergent light, it
is useful to proceed to this method of verification.
(2). Once the suitable section is chosen, it is necessary
to orient it; that is to say, to discover the trace of 001, and
that of the edge of the prism. It is to be remembered that the
extinction will be positive, according to the rule of Schuster
(p.*23,Fig. 19), when it is in the obtuse angle 001 Aoio, and
negative when it is in the acute angle.
a. The occurrence of the Carlsbad made, combined with
the trace of the easy cleavages, gives the complete solution of
the problem; it is enough then to measure the angle (cw) com-
prised between the two extinctions of the same sign. For
the purpose of avoiding all error it will be well to select from
the two supplementary angles that which has the same bisec-
trix as the angle 128° of the basal cleavages (Fig. 27).
For albite co =168° . extinction at + 20* in 010.
For oligoclase (i? =128°, extinction at o" in 010.
For andesine 00=112'', extinction at — 8** in 010.
For labradorite (^=96°, extinction at — 16* in 010.
For anorthite £^^^54°, extinction at — 37** in 010.
When one of the profiles 001, loi, 201, can be found, or
simply the cleavage of 001 and the coarse cracks parallel to
no or no, the acute angle 001 A icx) can be recognized; the
48 The American Geologist. Jauuary. i88S
trace of lOO is in fact in the obtuse angle 00 1 A lOi or ooi A2oi
But, most frequently, it is known a priore where the direc-
tion of negative extinction falls. Such is the case when it ex-
ceeds 20° and reaches the values characteristic of labradorite
or of bytownite; such also when the feldspar is bordered by
oligoclase.
(3). The search for sections 010 is often very long. The
stage devised by M. de Federov gives a useful means of cor-
recting the position of sections near 010. He has pointed out
a process for determining the direction of extinction; it con-
sists in the search for the direction of rptation necessary to
bring the nearest optic axis into the field, but it is not applica-
ble to albite, nor to oligoclase No. 2, nor to anorthit^.
It is in sections 010 that it is easiest to study the growth-
increments of the feldspars, and their changes of composition
step by step with their successive consolidations. It is not
rare to see labradorites, andesines and even oligoclases thus
succeeding each other. But the dominant type is relatively
very stable in each stage of the consolidation, and it is very
easy, generally, to specify without any uncertainty the nature
of the dominant feldspar. Whenever large crystals are sus-
ceptible of this examination in the face 010 (and the case is
very frequent) it is to be advised.
(4). To what extent do the errors of orientation affect the
readings of extinction? The general epures (plates I- VI I)
can reply to this question with precision. Let us suppose an
error of 10° made in the orientation of a section to be studied;
in other terms, let us carry forward the pole of the section to
the parallel 10° from that of 010. The epures give us, for each
position of that pole, the extinction referred to the trace of
010, and the angle of the trace of the cleavage 001 referred to
this same trace.
For albite this error of 10° in orientation of the chosen
sections gives rise to extinctions varying from 15° to 25*.
The mean error in oligoclase is, in the same manner, ±5^;
it descends in andesine to ± 4", and then rises slightly, to la-
bradorite and anorthite.
The mean error of one degree in orientation in the face
010 does not amount to half a degree in the angle of extinc-
tion on the cleavage 001. The theoretical reason for such a
Tn
4
0/0^-
fl
0To*»
I
The American Geoi4
730
iBo
TbeAI
/30
ISO
\
4
oro'
The A)
OiO
\
p
The Pittsburg Coal Bed, — White. 49
result is because, in most of the plagioclases, the zones parallel
to lines contained in 010 reach their maximum angle of ex-
tinction in the neighborhood of that section which serves ap-
proximately as the principal plane of elasticity, excepting in
anorthite. In the same manner, for the trace of 001, re-
ferred to the trace 010, in the same zones, the angles pass a
maximum in the neighborhood of 010. Their sum, or their
difference, ought, therefore, to vary but little, and 010 is hence
well chosen from all points of view.
THE PITTSBURG COAL BED.*
By I. C. White, Morgantown, W. Va.
Among the rich mineral deposits of the great Appalachian
field, the Pittsburg coal bed stands preeminent. Other coal
beds may cover a wider area, or extend with greater persist-
ence, but none surpass the Pittsburg seam in economic im-
portance and value. It was well named by Rogers (H. D.)
and his able assistants of the First Geological Survey of Penn-
sylvania, in honor of the city to whose industrial growth and
supremacy it has contributed so much. Whether or not the
prophetic eye of that able geologist ever comprehended fully
the part which this coal bed was to play in the future history
of the city which gave it a name we do not know; but certain
it is that the seven feet of fossil fuel which in Rogers' time
circled in a long black band around the hills, and overlooking
the site of Pittsburg from an elevation of 400 feet above the
waters of the Allegheny and Monongahela, extended up the
latter stream in an unbroken sheet for a distance of 200 miles,
has been the most potent factor in that wonderful modem
growth which has made the Pittsburg district the manu-
facturing centre of America, and which bids fair to continue
until it shall surpass every other district in the world, even
if it does not now hold such primacy.
That this claim for Pittsburg's supremacy is valid can
hardly be doubted when we see its iron, steel, glass and other
products going to every part of the western continent and
♦Vice-president's address before Section E (Geology and Geog-
raphy), Am. Assoc. Adv. Sci. 1897.
56 The Atnefican Geologist, January, i898
even invading the long established dynasties of the old world.
A brief account of the main characteristics of such an im-
portant member of the Carboniferous series can hardly fail
to be of some interest to geologists and others who desire
to learn more of this celebrated coal bed and hence it has
been chosen as my theme.
Age, The stratigraphical position of the Pittsburg coal
bed is at the base of the Monongahela River series of Rogers.
The thickness of this series varies from 250 to 400 feet in
different portions of the Appalachian field. It also includes
four other coal beds interstratified with sandstones, limestones
and shales, but none of these coals have much economic im-
portance since all are thin and impure except over quite
limited areas, so that the Pittsburg bed may be regarded as
the last of the great coal-making epochs of Carboniferous
time.
The lower and middle Carboniferous had passed; the
animals and most of the plants that characterize them had
vanished; the great Lepidodendra, Sigillariae, and Calamites
of the former floras had been succeeded by dwarfed and puny
species of their tribe, while the tree ferns alone of all the larger
plants appear to have flourished and attained considerable
size. The evening of the Carboniferous day was well ad-
vanced, since marine conditions in the Appalachian field had
terminated and brackish or fresh water conditions had arisen
which continued to the close of the Permian. At the end
of this latter epoch 1,500 feet of sediments had accumulated
above the Pittsburg coal + the thickness eroded since the
dose of the Palaeozoic, which latter most probably representi
a much greater thickness of rocks than the 1,500 feet re-
maining.
Prof. Fontaine and myself have shown (Report PP. 2nd
(Geological Survey of Pennsylvania) that beginning with the
horizon of the Wayncsburg coal at say about 350 feet above
the Pittsburg bed, the rocks contain a well defined Permian
flora, of types common alike to the I^crmian of Europe and
to the well recognized Permian beds of Texas (Bulletin G. S.
A. Vol. 3, pp. 217-218, 1892). Just where in the series this
flora was introduced we do not yet know because no sys-
tematic collections of fossil plants have been made between the
The Pittsburg Coal Bed, — White. 5 1
Waynesburg and Pittsburg coals, and in fact none until we
pass below the Pittsburg seam several hundred feet, and reach
marine conditions. The coal making epoch of the Appalach-
ian Carboniferous really culminated and its decline began
with the deposition of the Upper Freepprt bed at the summit
of the Allegheny River series of Rogers (No. XIII), since the
few fossil plants found in the 600 feet of the Barren or -Elk-
River strata which supervene between the Upper Freeport
and Pittsburg coals are either identical with or closely affil-
iated to Coal Measure types of plants that survive into the
Permian flora of Europe and Texas. This is also mainly true
of the last marine faunal types occuring at the horizon of the
Crinoidal limestone, about 300 feet below the Pittsburg bed.
and therefore in Bulletin 65, U. S. (i. Survey, page 19, the
dividing line between the Upper and Middle Carboniferous
was drawn through the midst of the Barren Measures (No.
XI\'), at the close of the Crinoidal limestone stage when
marine life became practically extinct in the x\ppalachian sed-
iments. Hence the 600 to 700 feet of strata extending from
the Crinoidal limestone to the Waynesburg coal, and enclosing
the great Pittsburg bed near the centre, may be considered
as of Permo-Carboniferous age, or so far as there is any evi-
dence to the contrary, they could just as well be classed as
•Permian.
The flora of this portion of the column has been studied to
only a limited extent, but so far as known, it consists as al-
ready stated mainly of those Coal Measure types which pass
on up into the undoubted Permian, while the fauna com-
prises only fresh or brackish water forms, concerning which
little or nothing is known, as the fossils (mostly minute) have
never been studied. The rocks themselves consist of a mon-
otonous succession of red shales, gray sandstones, and lime-
stones, often highly magnesian but only slightly gypsiferous,
and presenting much the same lithological appearance from
the Crinoidal limestone to the top of the Permian, 1,500 feet
above the Pittsburg coal.
The Xeuropteris morii Lx., and the large reptilian tracks
found by Lyell near (ireensburg, Pennsylvania, point to the
same conclusion with reference to the age of the Pittsburg
bed, namely that it belongs to the cjosing stage of the Car-
boniferous period, rather than to the middle of the same.
52 The Atnerican Geologist, January, i898
*
Area. Before the drill of the petroleum-seeker had pene-
trated every region of the great Appalachian basin, it was
supposed that the Pittsburg coal spread in a continuous
sheet under every portion of that area where its outcrop was
buried from view. This conclusion was based upon the un-
failing continuity of the bed southward for 200 miles from
Pittsburg to the head waters of the Monongahela, and also
westward into Ohio, and its reappearance on the river of that
name at Pomeroy, as also on the (jreat Kanawha at Ray-
mond City, Pocatallico, and Charleston. But the studies of
professor Orton and others in Ohio and my own in West
Virginia, aided by the petroleum drilling there, have shown
that the coal is absent, or but poorly developed over large
areas where it had formerly been considered present. Hence
to the list of counties of West Virginia named in Bulletin
65, United States Geological Survey, page 64, where this
coal is absent, or in poor development, must now be added
Doddridge, Tyler, and probably half of Wetzel, since two
tests with the diamond drill neai the centre of the latter
county found only two feet of coal at a depth of 425 feet
below the valley of Fishing creek. This area, together with
that previously known to be barren, or to have only a patchy
development in West Virginia and Ohio, will aggregate be-
tween 4,000 and 5,000 square miles, a rather startling figure
when subtracted from the supposed area of a coal-bed so
valuable as the Pittsburg in its developed regions.
There has been much speculation as to the area which
this coal may once have covered. The isolated patches of
the bed in the Georges creek and North Potomac region;
the few knobs of it in Preston, Barbour and Upshur counties
of West Virginia, together with its presence in the solitary
peak of Round Top in Bedford county, Pennsylvania, 45
miles from any other outcrop of the bed, and far east of the
Allegheny mountains, have led many geologists to believe
that the Appalachian Coal Measures may once have ex-
tended northwestward to the Lake region, and eastward pos-
sibly to the North mountains, or even to the Blue ridge,
having been removed from all this wide expanse by the enor-
mous erosion to which it has been subjected since Carbon-
iferous time. Whether the limits thus assigned were ever
The Pittsburg Coal Bed. — White, 53
attained by the spread of Coal Measures, we shall probably
never know to a certainty, but that there is no inherent im-
probability in the hypothesis, will appear from the fact that
the oldest member of the Carboniferous period, the very
hard and erosion-resisting sandstones of the Pocono, with
its included coal-beds, extends to the North Mountain re-
gion at several points along that great ridge. Of course if
the Coal Measures ever covered an area as wide as this
lowest member of the Carboniferous, the probabilities are
that the area of the Pittsburg bed which has escaped erosion
is only a fragment of its former extent. But however this
may be, its entire area of workable coal remaining in the
states of Pennsylvania, Ohio, West Virginia, and Maryland,
does not probably exceed 6,000 or 7,000 square miles.
Structure, Dr. J. J. Stevenson, of the University of New
York, was the first geologist to make a detailed study of the
Pittsburg coal bed, and to describe the peculiar structure
which so distinctly characterizes it, that the coal seam may
be' thereby identified with great certainty over a wide area.
In Report K, Second Geological Survey of Pennsylvania,
he shows that a series of thin parting slates and clays sub-
divide the bed into several definite members, which may be
grouped as follows:
'Roof coals.
'Over"-clay.
Breast" coal.
Parting.
Bearing-in" coal.
Parting.
Brick" coal. •
Parting.
^'Bottom" coal.
*'The "roof" coals are a number of thin layers of coal
(two to twelve inches each) separated by shales or clays of
varying thickness. Some of the layers are good coal, while
others contain much dirt and other impurities. Their num-
ber ranges from one to eight, or even more, and their com-
bined thickness seldom exceeds three and one-half to four
feet, while the separating slates and clays may be only half as
54 The American Geologist, Jauaary, uj9fe.
much, or they may often exceed the coal in thickness by two
or three times. In practical mining operations all of this
"roof" coal is wasted, because the coal layers make a good
support for the overlying strata, and are, therefore, left as
the roof of the mine. In this way about 2,000 tons per acre
of the Pittsburg coal is always lost w^ithout any attempt to
recover it. This waste is so large that some of the mining
companies are considering the question of putting in crush-
ing and washing machinery with a view to taking down these
roof coals, and thus preventing the great loss of fuel which
their abandonment entails upon any mine. There is no
doubt that the time will come, many generations hence, when
at great cost, the Pittsburg bed will be re-mined to secure
the coal which is now rejected, both in its roof and bottom
members, since all of it would be valuable fuel if freed from
the included slates and clays.
The "over-clay" is an impure fire clay, and varies much
in thickness, sometimes almost disappearing, and again
thickening up to two or even five feet. The clay is usually
mottled and much slickensided, so that it becomes a danger-
ous trap when left as a mine support, since large pieces of it
will drop from the roof without any warning sound. Hence
it is generally taken down at once, and the miner, has, there-
fore, given it the name of "draw-slate" in many regions.
It often contains what appear to be stems and rootlets of
plants.
The next succeeding (dow^ilward) division of this seam»
the "breast coal" of the miners, also often termed the "main
bench," is the most important and valuable division of the
whole bed. Its thickness gradually increases from the Pitts-
burg region (where it is usually about three feet) up the
Monongahela, attaining a maximum of six feet at Browns-
ville, while to the eastward in the (leorges creek and North
Potomac basin of Maryland and West Virginia, it increases
still more to seven and one-half or even ten feet. The top
of this member is nearly always of a bony nature for a thick-
ness of one to four inches, and frequently this must be sep-
arated and rejected in mining, but even where this is not
required, the top of the "breast" coal is distinctly harder than
the rest of it, and inclined to a cannelly structure. Westward'
The Pittsburg Coal Bed, — White, 55
to the Ohio river this "breast" division thins and in the
(jlendale and Moundsville shafts is only 21 inches, accord-
ing to Mr. J. W. Paul, state mining inspector for West Vir-
ginia. It is still perfectly distinct, however, with the twin
slates one-fourth of an inch thick each, and enclosing six
inches of "bearing in" coal immediately below.
The "bearing-in" coal is so named by the Monongahela
river miner, because in mining operations the under-cutting
of the "breast" coal is made in this layer, the latter being
then wedged or blown down, and the "brick" division subse-
(juently taken up. The "bearing-in" coal is usually brilliant
and pure, varying in thickness from three to six inches, and
enclosed by two thin parting slates, so much alike in color
and structure as to be almost indistinguishable. Their color
is usually a dark, mottled gray, and they vary in thickness
from one-fourth to one inch. The persistency of these twin
slates over all the regions drained by the Monongahela and
cast to the Georges Creek and Xorth Potomac field, while
westw^ard to Wheeling, Bellaire and the neighboring regions
of Ohio they still appear to be present, is one of the remark-
able features of this coal-bed. When, however, the areas of
this coal south of the little Kanawha river in West Virginia,
and west from the Muskingum in Ohio, are examined, these
twin slates are not found, or if represented are no longer
recognizable as the Monongahela partings, but the "roof"
coals and "over-clay" appear to be present.
The "brick" coal comes next under the lower of the twin
slates, and was so named by the Monongahela river miners
because it comes out in oblong, rectangular blocks resem-
bling the shape of common bricks. It is usually about one
foot thick. The parting which separates the "brick" coal
from the next lower member is always present along the
Monongahela from Brownsville to Pittsburg, and it is also
represented in the Georges Creek and North Potomac field,
])ut in the Fairmont region it is only occasionally present,
the bed there being generally undivided below the "bearing-
in" coal.
The "bottom" member is from twelve to twentv inches
thick along the Monongahela, and contains so many thin,
.^laty, sulphurous laminae, that it is usually not taken out in
56
TJic Americati Geologist,
Jannary, 189S
mining, and thus another thousand tons per acre of this bed
is wasted, though in the Fairmont and Cumberland (Georges
Creek) regions it is mined and sold with the rest of the coal.
The twelve to fifteen inches of good fuel in this member
could always be recovered by crushing and washing.
The structure here described can be best illustrated by
giving an actual section of the coal at its type locality. In
the Ormsby mine at Twenty-first street, Pittsburg, where
mining operations have been carried on for more than 60
years, Mr. J. Sutton Wall took the following measurements
(K 4, Second Geological Survey, Pennsylvania, page 177):
Inches.
"Roof".. \
Coal 6
Clay 2
Clay 8i
Parting o^
Coal 2
Clay g
Coal 8
Parting o|
Coal 9
Clay oj
Coal 5
Parting q\
Coal 2
Parting o\
Coal 2
^
^56"
"Over"-clay 9 "
"Breast" coal 33 " ^
Parting o\ \
"Bearing-in" coal 4 |
Parting oi J^ 6ir
"Brick" coal 10
Parting oj
"Bottom" coal 14
Total thickness 10 ' 63 "
Substantially this structure may be seen at every mine
between Pittsburg and Brownsville, and on beyond for many
miles (see Reports K and K 4, Second Geological SurveVr
Pa).
East of the Monongahela, on the Youghiougheny river,
the same structure is well illustrated by two sections which
Mr. W. S. Gresley, F. G. S. A., measured for me with great
care at the W. L. Scott estate mines, of which Mr. Gresley
is superintendent at Scott Haven, Pennsylvania. The first
one of these is near Scott Haven, and reads as follows:
The Pittsburg Coal Bed.— White.
57
Inches.
■\
Coal, several films of dirt 3l
ShaJe, black, earthy 2
Coal 2i
Shale, gray, streaks of coal near top .11
Bone (hard, dull, impure, coaly, layer) i
Coal 2l
Shale, black, coaly i
Coal 3
Slate, gray, with irregular coal streaks 4i
Coal, compact, free from "binders" . . 9^
Slate, with coal streaks \\
Coal 2i
"Over"-clay (impure, fireclay, light gray above, getting
browner and then a much darker gray with coal
streaksof irregular shapes, especially towards base) . \o\
"Breast" coal (with i^ inches of bone at top, and
next 10" harder than the rest of bench) 41 J'
Shal'e, dark grayish brown, mottled of
"Bearing-in" coal, clear and brilliant 4
Shale, dark grayish brown, mottled oj
"Brick" coal clear and brilliant : 11
Shale, parting o| ,
i' Coal with a few thin dirt layers. I2| |
"Bottom" coal ] Shale q\ \
( Coal, bright, clean 2 I
Total thickness of bed 10 ' 5I "
The other section made by Mr. Gresley is from the "Pa-
cific Mine," near Scott Haven; and three miles distant from
the section just given. It is as follows:
Inches.
\l^
Coal
iX
MO'
Shale, light 2
Coal, with a few dirt partings 5
Shale 0%.
Coal 2
"Roof " . . -i Fireclay, light, bastard \^%.
Coal, with a few dirt partings 9
Shale \\
Coal with thin dirt lenses 12
Shale oj
Coal 134:
•
i Fireclay, light, inferior, much darker
"Over"-clay \ toward base with meandering
( streaks and veins of brilliant coal .
"Breast" coal, — Upper 10 inches harder than ^
the rest 42 '
Shale, mottled oj
"Bearing-in" coal 33/
Shale, mottled o^
"Brick" coal 1 1
Shale, parting o'^
"Bottom" coal 14 ' J
Total thickness of bed 10 ' 1 1 3 «
lOJ^
\
7oh
58 The American Geologist, January. i898
A third section measured by Mr. Gresley, three miles dis-
tant from either of these differs so little from them that it is
useless to give it.
How perfectly this great coal-bed preserves the Pitts-
burg type of structure, is shown from the following sec-
tion sent me by Mr. R. L. Somerville, superintendent
of the Georges Creek Coal and Iron Company, Lonaconing,
Maryland. The locality is east of the Allegheny mountains,
and 150 miles from Pittsburg. It is as follows:
Inches.
"Roof" coal with slate parting below 20
"Breast" coal 6" of bone on top 91
"Slate" I
"Bearing in" coal 4V^
Slate oK
"Brick" coal 16
Slate oVa
"Bottom" coal IS
Total thickness of bed 12', AtVi"
This type of structure is practically universal over all of
the Pennsylvania, Maryland and eastern Ohio area of the
bed. The different members vary considerably in thick-
ness, as for instance the gradual increase of the "breast"
coal from three feet at Pittsburg to six at Brownsville, 58
miles up the Monongahela river, or to seven and even ten
feet in the Georges creek and North Potomac regions of
Maryland and West Virginia, or a decrease may take place
in the same to thirty and sometimes to twenty inches, as
in the Wheeling and Bellaire regions, but each of the main
sub-divisions can be distinctly recognized, so that whether
at Fairfax Knob, on the summit of the Allegheny mountains,
3,200 feet above the sea, or deep down in the centre of the
great Appalachian trough buried under 1,500 feet of sedi-
ments, the explorer can readily identify this great coal-bed,
not only from its associated rocks, but from its stratagraph-
ical elements as well, and often from even the fracture of the
coal. I once had a practical illustration of this latter pecu-
liarity of the Pittsburg seam. About the year 1880 a coal
bed was discovered near the summits of the hills, south from
Huntington, West Virginia, and on one of my excursions to
The Pittsburg Coal Bed, — White, 59
the southern portion of the state, with the University stu-
dents of geology, the mayor of Huntington requested me to
deterniine, if possible, to what horizon the coal belonged.
It proved an easy problem to identify it since the Crinoidal
limestone, with its characteristic fossils, was easily found in
the bed of Four Pole creek, fifty feet above the Ohio, and
above it the ordinary rock succession of the Barren or Elk
river series. But, being anxious to know what the miner
who was digging the coal thought of the matter, he was in-
terrogated, and replied as follows: "I don't know anything
about geology, but I dug coal several years in the Pittsburg
seam, along the Monongahela, and this coal reminds me of
the Pittsburg in the way it breaks into blocks." Thus had
the miner correctly diagnosed the horizon of the bed by his
own peculiar methods, though 300 miles distant from where
he had learned its structure, with only the tools of his trade
and his bright observing mind as his guidance, strong testi-
mony certainly to the persistence of even the internal struc-
ture of the bed.
The oil-well driller is required to identify this coal cor-
rectly in the great petroleum districts of West Virginia and
Pennsylvania, between the Ohio and the Monongahela rivers,
where it is buried from sight by the Permian beds all the
way from 500 to 1,500 feet. It is there a key-rock for deter-,
mining the amount of casing and the depth of the oil sands,
and thus many dollars of expense depend upon the correct-
ness of the driller's identification. This he does by observ-
ing the character of the drillings as brought to the surface
by the sand pump, or in other words he observes the strati-
graphic succession in his own peculiar way, and in the hun-
dreds and even thousand of holes drilled in this area, he has
only two or three mistakes charged against his accuracy of
discrimination.
A word of friendly criticism and kindly warning concern-
ing the methods of the United States Geological Survey,
especially in its Coal Measures work, but equally applicable
to the other formations, becomes in this connection an im-
perative duty.
In recent years a theory seems to have been adopted by
the United States geologists who have been studying the
6o The American Geologist, January, \m>
Coal Measures, that no t:oal bed can be certainly identified
beyond the area of its continuous outcrop, and hence must
be given a local name for every isolated area, thus adding
greatly to the burden of geological nomenclature, a fault of
geologists everywhere, which has become so grievous that
the International Congress has been invoked this summer
to consider a remedy for the matter. The confusion pro-
duced by this useless giving of many names to the same
thing is an evil for which a remedy must be speedily found,
or it will soon bring all geological work into deserved con-
tempt in the minds of laymen.
The United States geological survey which is doing such
splendid work along many lines ought to be a model in the
matter referred to, but is now the chief offender. Let us
hope and urge that a reform in the methods of work which
lead to such undesirable results shall soon be inaugurated.
The old and well established names of the New York,
Pennsylvania and Virginia surveys, rendered classic by the
labors of such men as Hall, Emmons, the Rogers brothers,
Lesley, and many other faithful geologists, should not be
lightly cast aside, and the work of these noble pioneers ig-
nored, unless positive error can be proven.
It is no argument in favor of the methods complained of^
to ^ay that the geologist is not reasonably certain of identity
of horizon, for that is the fault of the observer and his
methods in not wisely attacking the problems of stratigraphy.
It will hardly do to admit that the untutored miner and un-
lettered petroleum driller are better geologists than men
trained as experts in geology. What we need more than
anything else is a closer and more minute study of the in-
dividual beds, such as Mr. Gresley, for instance, has been
making on the Pittsburg coal, and if this method of work
were pursued the geologist would find but slight need of the
introduction of new names for old and well-named things.
It was with the hope of emphasizing the necessity and impor-
tance of observing the smaller details of stratigraphy more
closely, that I have dwelt at length upon the characteristic
structure of a single coal bed.
Review of Recent Geological Literature, 6i
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
Seventeenth Annual Report of the United States Geological Survey
to the Secretary of the Interior y 1895-96. Charles D. Walcott, Director.
In Three Parts. Washington, 1896. Part I. Director's Report and
Other Papers. Pages xxii, 1076; with 67 plates, and 43 figures in the
text. — Part II. Economic Geology and Hydrography. Pages xxv,
864; with 113 plates, and 74 figures in the text. — Part III. Mineral
Resources of the United States, 1895: (first volume) Metallic Products
and Coal, pages xxi, 542; (second volume) Nonmetallic Products, ex-
cept Coal, pages 543-1058; with 13 plates and 3 figures in the text.
The report of the Director, in 200 pages, gives brief summaries of the
work done by the several divisions of the survey, a detailed st£ltement
of the expenditures during the fiscal year, and a short biographical
sketch of the late Prof. George H. Williams. In geological explora-
tion and mapping, four parties worked in the New ^ England region;
seven in the Appalachian region ; four in the Atlantic Coastal Plain
region; four in the Interior or Mississippi region; six in the Rocky
Mountain region; and seven in the Pacific region. Six parties conduct-
ing field observations in paleontology are reported. In topographical
mapping, work was prosecuted in twenty-four States and Territories.
The entire area surveyed during the year was 48,066 square miles, of
which about 44,000 square miles are designed for publication on the scale
of 1:125,000, or about two miles to an inch, while the remainder is
nearly all to be on the scale of 1:62,500. The total appropriations for
the survey during the fiscal year ending June 30, 1896, were $675,530.75;
and the total expenditures $647,075.60.
Seven other papers are published in Part I, as follows: Magnetic
Declination in the United States, by Henry Gannett, pages 203-440,
with two plates and three figures; A geological Reconnaissance in
Northwestern Oregon, by Joseph Silas Diller, pages 441-520, with plates
4-16, and figures 4-17; Further Contributions to the Geology of the
Sierra Nevada, by Henry W. Turner, pages 521-762, with plates 17-47,
and figures 18-22; Report on Coal and Lignite of Alaska, by William
Healey Dall, pages 763-875, with plates 4&-58, and figures 23-25, and three
appendices (I. Report on the Fossil Plants Collected in Alaska in 1895,
as well as an Enumeration of those previously known from the same
region, with a Table showing the Relative Distribution, by F. H.
Knowlton, pages 876-897; II. Report on Palaeozoic Fossils from
Alaska, by Charles Schuchert, pages 898-906; III. Report on the
Mesozoic Fossils, by Prof. Alpheus Hyatt, pages 907, 908); The
Uintaite (Gilsonite) Deposits of Utah, by George Homans Eldridge,
pages 90^949, with plates 59, 60, and figures 26-33; The Glacial Brick
Clays of Rhode Island and Southeastern Massachusetts, by N. S. Shaler,
J. B. Woodworth and C. F. Marbut, pages 951-1004, with plates 61, 62,
and figures 34-43 (reviewed in the last Am. Geologist, p. 328); and
62 The American Geologist. January, i898
The Faunal Relations of the Eocene and Upper Cretaceous of the
Pacific Coast, by Timothy W. Stanton, pages 1005- 1060, with plates
63-67.
Mr. Gannett's paper, compiling and discussing the magnetic declina-
tion in all parts of the United States, is designed to meet the needs of
land surveyors who use the magnetic needle, or who have occasion to
deal with old surveys run by the needle. The resulting map shows lines
of equal declination for the year 1900, the extremes being about 22
degrees west on the northeastern boundary of Maine, and 23 degrees
east at Juan de Fuca strait.
The part of northwestern Oregon described by Mr. Diller extends
from the Columbia about 200 miles south to the Umpqua and Coquille
rivers, with a width of about 75 miles back from the coast. It is found
that the chief mass of the Coast range, from near the Columbia to the
Coquille, consists of Eocene rocks, which are shales and sandstones,
with basalt and associated tuffaceous materials. Oligocene, Miocene,
and scanty Pliocene beds occupy the lower country. Above these are
marine Pleistocene beds, formed during a depression of 200 feet or
more; but this was succeeded by an elevation of the land considerably
above its present hight, as shown by the submarine continuation of the
Columbia river valley. The chief mineral resources are .deposits of coal,
of which about 7S,ooo tons were mined in 1895 ; limonite, scantily mined
in several places; and gold, with platinum, iridium, and osmium, which
occur most notably in black sands along the sea beach and to a short
distance at and north of the mouth of the Coquille river.
Mr. Turner supplements his previous memoir on the Sierra Nevada,
published in the Fourteenth Annual Report of this survey, of which a
preliminary abstract appeared in the Am. Geologist (Vol. XIII) for
April and May, 1894. His later articles in this magazine for June, 1895,
and June, 1896, present portions of the subjects which are more fully
treated here. The Sierra Nevada is regarded as "a block of the earth's
crust that has been quite rigid since middle Cretaceous time, although
it has since, in common with most of California, experienced a con-
siderable elevation." This paper contains much detailed description of
the rocks of the mountain belt, both sedimentary and igneous, with
many plates of their thin sections.
The lignitic coal deposits of Alaska, described by Dr. Dall, occur in
the Kenai formation, which has an extensive geographic distribution.
They will probably be profitably mined for domestic use and for expor-
tation to California, competing with the lignite of British Columbia.
The Kenai group, consisting of conglomerate, sandy slates, and shales,
with a rich fossil flora, wood, and lignite, is regarded as probably
Oligocene and as of the same age with the Atane leaf beds of Greenland
and the plant beds of Spitzbergen, although Heer classed them all as
Miocene. The discussion of this question is accompanied by ^ood
description of the other Tertiary formations of Alaska. The ensuing
Glacial and Postglacial periods have been supposed (rightly, according
to the reviewer's opinion) to be represented by the Ground ice forma-
Review of Recent Geological Literature, 63
tion, exposed on the shore of Eschscholtz bay and in other localities,
and the overlying Kowak clays, which contain many mammoth bones
and tusks; but Dr. Dall inclines to assign them (and also the beds up to
5,000 feet in the basal part of Mt. St. Elias, containing numerous species
of marine shells, all now living, as described by Russell) to Pliocene
rather than Pleistocene time. The concluding portion of the paper and
its appendices treat very fully of Alaskan paleontology.
Immense supplies of a variety of asphalt, named uintaite by Prof. W.
P. Blake in 1885, but more recently known commercially as gilsonite,
occur in the west half of the Uinta basin of Utah. The uintaite, as
described by Mr. Eldridge, fills straight vertical cracks in Eocene strata,
its veins being from a sixteenth of an inch to eighteen feet across, and
from a few hundred yards to eight or ten miles long. The cracks are
thought to have originated when the gentle synclinal fold of this basin
was formed, and to have been immediately filled by injection of the
asphalt in a plastic or melted condition: but the author cannot suggest
the condition in which it existed prior to its flow into the cracks.
Uintaite is chiefly used in the manufacture of varnishes, for which it is
delivered in St. Louis and Chicago at $40 to $50 per ton.
Mr. Stanton, from his study of the Chico and Tejon faunas, refers
the former to the Cretaceous and the latter to the Eocene. The sup-
posed Tertiary types in the Chico fauna are shown to be few and limited
to persistent species which have changed little from the Cretaceous to
the present day. In California these formations are conformable,
wherever sections have been discovered; and it is suggested that the
later fauna was not here developed from the earlier, but succeeded to its
place by migration.
Part II comprises eight important papers, as follows: The Gold-
quartz Veins of Nevada City and Grass Valley, California, by Walde-
mar Lindgren, pages 1-262, with 24 plates, and n figures in the text;
Geology of Silver Cliff and the Rosita Hills, Colorado, by Whitman
Cross, pages 263-403, with plates 25-36; The Mines of Custer County,
Colorado, by Samuel Franklin Emmons, pages 405-472, with plate yj*
and figures 38-43; Geologic Section along the New and Kanawha Rivers
,in West Virginia, by Marius R. Campbell and Walter C. Mendenhall,
pages 473-511, with plates 38-49; The Tennessee Phosphates, by Charles
Willard Hayes, pages 513-550, with plates 50-55, and figure 44; The
Underground Water of the Arkansas Valley in Eastern Colorado, by
Grove Karl Gilbert, pages 551-601, with plates 56-68, and figures 45-49
(reviewed in the Am. Geologist, Jan., 1897, Vol. XIX, pp. 57-60);
Preliminary Report on Artesian Waters of a Portion of the Dakotas, by
Nelson Horatio Darton, pages 603-694, with plates 69-107, and figures
50-65 (reviewed in the last April Am. Geologist, pp. 274-6); and The
Water Resources of Illinois, by Frank Leverett, pages 695-828, with
plates 108- 1 13, and figures 66-70 (reviewed in the last June Am. Geol-
ogist, p. 418), to which a final chapter. An Account of the Palaeozoic
Rocks Explored by Deep Borings at Rock Island, 111., and its Vicinity,
is contributed by J. A. Udden, pages 829-849, with figures 71-74.
64 The Anurican Geologist, ' January, i898
In these economic and hydrographic papers, and in the two volumes
forming Part III, on the resources of our mines and quarries in 1895,
compiled by many specialists under the supervision of Dr. David T.
Day, a vast amount of information is presented, descriptive, historical,
and statistical, which is adapted directly to promote the industries and
material prosperity of the whole country.
The first paragraph of Dr. Day's report sums it up very concisely,
and indicates its close bearing on our business interests, as follows:
"The total value of the mineral products of the United States for the
year 1895 increased nearly one hundred million dollars beyond the
value of 1894, or from $527,144,381 to $622,687,668. This increase is a
long step toward recovery from the depression to which the mineral
industry, like all others, has been subjected. The total value is slightly
less than the greatest we have ever known, which was over $648,000,000,
in 1892. In terms of 'quantities produced, instead of value received,
189s is greatest. In other words, prices are lower."
Papers on iron ores, by John Birkinbine, and on the iron and steel
industries, by James M. Swank, occupy 49 pages; statistics of gold and
silver production, 8 pages; and a paper on copper production, mainly
statistical, by Charles Kirchhoff, 49 pages; while lead, zinc, quicksilver,
manganese, tin, aluminum, nickel and cobalt, chromic iron, antimony,
and platinum, are similarly noticed, with tables of their recent yearly
production. The paper on coal, by Edward W. Parker, fills 258 pages.
Coke (78 pages), petroleum (iii pages), and natural gas (18 pages), are
treated by Joseph D. Weeks; asphaltum (8 pages), by Mr. Parker; stone
(S3 pages), by William C. Day; clay (64 pages), by Jefferson Middle-
ton; cement (13 pages), by Spencer B. Newberry; and precious stones
(32 pages), by George F. Kunz; besides other papers, with statistics, on
flourspar and cryolite, mica, asbestos, graphite, mineral paints, barytes,
abrasive materials, phosphate rock, sulphur and pyrites, gypsum, salt,
and mineral waters. w. u.
Iowa Geological Sun/ey, Vol. 6, Annual Report, i8g6, with ac-
companying papers. Samuel Calvin, State Geologist. (555 pp., 11
pis., II maps; Des Moines, 1897.)
From the fifth annual report of the state geologist, which is includetf
in this volume, the following facts concerning the work of the Iowa
survey are taken: During 1896 six counties were surveyed and during
previous years fourteen counties. In twelve other counties the field
work is partly or wholly done, making a total of thirty-two counties in
which detailed areal investigations have been conducted. At the same
time certain features of other counties have been studied in connection
with reports on special subjects, as the report on coal deposits or that
on artesian wells. In the areal county work those counties have been
selected first which contain deposits of great economic importance or
which offer a means of solution of a large number of geological prob-
lems. During the last year special attention has been given to the
study of the Devonian, the Coal Measures and the Pleistocene, and in
Review of Recent Geological Literature, 65
the last a marked advance has been made, due largely to the work of
Messrs. Calvin and Bain. A summary statement of the results of their
study of the drift deposits has already been given in this journal (Vol.
XIX, pp. 270-272, April, 1897).
The present volume contains reports on six counties, each report
being accompanied by two maps, one showing the pre-Pleistocene and
the other the Pleistocene peology, but the latter map is omitted in the
report on Madison county. These county reports are as follows: John-
son and Cerro Gordo counties, by Samuel Calvin; Marshall county, by
S. W. Beyer; Polk and Guthrie bounties, by H. F. Bain; Madison
county, by J. L. Tilton and H. F. Bain. The reports on Johnson and
Polk counties have already been reviewed in this journal (Vol. XX, p.
273. Oct., 1897; Vol. XX, p. 334, Nov., 1897).
A geological map of the state is presented which shows the outlines
of the following divisions: Algonkian, Cambrian, Ordovician, Silurian,
Devonian, Mississippian, Des Moines, Missouriah and Cretaceous. This
map is more accurate than those formerly published, as must necessarily
be the case as the detailed work of the survey is extended. The limits
of the Cretaceous are more carefully defined and the rocks of this
system are found to cover considerably more territory than was sup-
posed a few years ago. The same increase in the known geographical
limits of the Cretaceous is also evident in the later reports of the
Minnesota survey. u. s. G.
Volcanoes of North America: a reading lesson for Students of Ge-
ography and Geology, Israel C. Russell. New York. The Mac-
millan Company, 1897. Octavo, 346 pages, $4.00.
This review is quite similar in scope and plan to the former works
of the same author on the lakes and on the glaciers of North America.
It opens with a chapter on the characteristics of volcanoes, occupying
126 pages, in which Stromboli, Vesuvius, Krakatoa, the Hawaiian
islands and the lava fields of the Deccan and of Columbia are taken as
types, to which is added also a note on the trap-rocks of the Newark
system, the last being the most recent of the volcanic epochs of the
Atlantic side of North America.
The author is responsible for many of the descriptions here given,
having examined several of the most important volcanic regions of
North America, but he has compiled from others many other descrip-
tions, some being from the reports of the United States Geological
Survey, and from the Geological Survey of Mexico. Great value is
added to the work by the fine illustrations with which it is accompanied.
The volume is a welcome addition to the geological literature of North
America, and serves to supply for America what those of Scrope and
of Geikie have given to the geology of Europe.
Without attempting a thorough review, attention may be called to
the lack of mention of recently extinct volcanoes in New Mexico, and
even in Texas, further east than has been allowed by the author. He
specifically excludes some which have been enumerated more recently
66 The American Geologist, January. 1888
by Hill in Science (Oct 15, 1897), first described by Marcou in 1857.
Again, there is some question as to the propriety of including the
central area of the Black Hills and of other similar mountain ranges
in a description of laccolitic phenomena^ and least of all in the category
of volcanoes. The axis of uplift of the Black Hills dates from Archaean
time as old as the protaxis of New England, and has certainly main-
tained an island in the ocean during all its subsequent geological history.
There have been later upliftings, both gradual and catastrophic, but there
is no evidence that the Mesozoic and Tertiary beds ever passed intact
over the summit of Custer and Harney peaks. It is well known that
the Potsdam sandstone of the region is composed of debris of the older
rocks, including Potsdam gold placers derived from lodes that must
even at that date have been elevated above the level of the ocean. There
are no known laccolites or volcanoes in the region of the Black Hills
of date earlier than the Mesozoic and probably not earlier than the
Tertiary. But Bear Butte, on the eastern side, is probably a remnant
of a late intrusion, while Heenya Kaga, on the west side is an extinct
volcanic crater later at least than the Carboniferous, and should be
added to the list of Hill of extinct craters further east than the Spanish
peaks. N. H. w.
BeitrCLge zur Kenntniss einiger Palceozoischer Faunen Sud-Amerikas,
von Herrn. E. Kayser in Marburg, Hess. (Reprint, a. d. Zeitschr. d.
Deutsch. geolog.Gesellschaft, 1897.)
This work is devoted to a description of the Paleozoic faunas of the
strata of the Argentine Confederation, chiefly its middle and northwest-
ern parts, and of lake Titicaca in Bolivia. The region is that of the
high table land on the eastern slopes of the Andes, where these moun-
tains change from a direct north to a northwest course.
Dr. Kayser had already described a number of Cambrian and other
fossils from this region, and now adds largely to the number and illus-
trates his paper with six excellent plates in which the new species are
figured.
The Cambrian fossils occur in a fine grained micaceous sandstone,
having quartz pebbles and seams of slate. The following species are
described: Liostracus steinmanni, Lingulella ci.ferruginea Salt., L.
ulrichi L. of. davisii Salt., Agnostus irugensis [Section Laevigati],
From a careful study of the species Dr. Kayser considers that these
fossils indicate the horizon of the Paradoxides beds.
The above author also revises his opinion as to the age of the Argen-
tine Cambrian fauna formerly described by him. On the strength of the
occurrence of Orthis lenticularis and of an Olenus he had referred this
fauna to the upper Cambrian, but in concurrence with Dr. W. C.
Brogger he is now inclined to think that the supposed Olenus should
be referred to Crepicephalus (Ptychoparia), and that the Orthis alone
will not confirm the reference to Upper Cambrian. This change he is
the more inclined to since the fauna described in the present paper, and
Review of Recent Geological Literature, 67
that previously made known, come from the same yellow-brown, fine-
grained micaceous sandstones.
The Lower Silurian fauna occurs in a sandstone in the province of
Salta, in northwest Argentine, but in limestone and dolomite in the
middle of that country, in the province of San Juan. The species de-
scribed are: Megalaspis sp., Bellerophon sp., Didymografptus sp.,
Illenus argentinus, Maclurea avellanidcB, Leptana sericia Sow., Orthis
ccBlligramma Dalm (?).
The species here figured with others previously described are consid-
ered to indicate a considerable range of Lower Silurian beds, including
the orthoceratite limestone at the base and other beds toward the top
of the system.
The Devonian fauna of middle Argentina is contained in clay slate
(lower part of the terrane) and slate and graywacke (upper part).
The following species are described:
Crypk(pus, PhacoPs cf. rana Green, Homalonotus sp., OrthoceraSy
sp., Naticopsis ? sp., Bellerophon %^,yBellerophon aff. murchisoni d*
Orb., Conulara quichua A. Ulrich, Tentaculites sp., Leptodomus sp.
Pholadella radiata Hall, Allorisma sp., TropidoUptus fascifer n. sp.,
Liorhynchus bodenbenderi n. sp., Liorhynchus ? brackebuschi, n. sp.
Meristella ? sp., Leptoccelia acutiplicata Conr., Vitulina pustulosa Conr.
Spirifer antarcticus Morr. and Sharpe, Orthothetes sp., Orthothetes
cf. arctostriatus Hall, Chonetes falklandica Morr. and Sharpe, Chone-
tes fuerlensis, n. sp., Chonostrophia, Lingula {Dignonia) subalveata
n. sp., Orbiculoidea cf. humilis Hall.
The fossils are considered to indicate the lower and middle parts of
the Devonian system.
In this region the Silurian (Upper) is wanting, as the Devonian beds
rest directly upon the Lower Silurian limestone, and consist of strata
)f the kind above described, having a thickness of several hundred to
two thousand metres. Three fossil iferous horizons have been recognized
in this mass of sediment.
The Devonian fossils of lake Titicaca were found in loose pieces
scattered over the surface of an island-like elevation in the lake and
plain. The fossils found were Leptoccelia flabellites Con., a Retzia
and a Homalonotus. G. F.
Petrology for Students, An Introduction to the study of rocks un-
der the microscope. By Alfred Harker. (2nd edition, revised, viii
and 334 pp.; University Press, Cambridge, 1897, price, 7s. 6d.)
The second edition of this text book, revised throughout and in
part rewritten, does not differ materially in manner of treatment from
the well known first edition, which was noted in the Geologist,
vol. xvii, p. 327, and thus does not require an extended review. The
divisions of igneous rocks — plutonic, h ypabyssal and volcanic — ^are
retained, and the amount of detail as regards reference to special types
and descriptions is increased, especially for American localities. The
68 The American Geologist. January, i«98
«
author has made it a point to devote more attention to American
rocks, and references to the work of writers on petrology on this side
of the Atlantic are numerous. u. s. G.
Geological Section from Moscow to Siberia and Return. By Persi-
FOR Frazer. (A brochure of 52 pages read before the Academy of
Natural Sciences of Philadelphia, Oct. 26th, 1897.)
The paper in question is an admirable summary of the chief points
of geologic interest seen by the author on the great excursion to the Ou-
rals previous to the meeting of the International Congress of Geologists
at St. Petersburg.
Dr. Frazer, as he states, has drawn freely upon the splendid guide
prepared with such great labor and expense by the Russian geologists
but he has so interwoven his own observations with the luminous details,
given in the guide as to make a very interesting story concerning the ge-
ology of the region traversed. A born diplomat, Dr. Frazer has treated
with much skill, and in the happiest manner, the extremely delicate
question of the disputed points in the Oural mountain region. His ready
and accurate knowledge of French has enabled him to perform a valua-
ble service for his less fortunate brother geologists, by epitomizing in
good English the main features of interest comprised in the Russian
(French) guidebook. His tribute of praise for the Tzar, the Russian
geologists, and all the Russian people, is not less happy than just.
I. c. w.
MONTHLY AUTHORS' CATALOGUE
OF American Geological Literature,
Arranged Alphabetically*
Banni8ter» H. M.
The drift and geologic time. (Jour, of Geol., vol. 5, pp. 730-74:j,
Oct-Nov. 1897.)
Berkey, C. P.
Geology of the St. Croix dalles. Pt. I. (Am. Geol., vol. 20, pp^
345-383, pis. 20-22, Dec. 1897.)
Burwashy E. M.
Geology of the Nipissing-Algoma line. (Ontario Bureau of Mines,
6th [1896] Rept., pp. 167-184, 1897.)
Chamberlin, T. C
A group of hypotheses bearing on climatic changes. (Jour, of Geol.,
vol. 5, pp. 653-683, Oct.-Nov. 1897.)
Clarke, J. M.
A sphinctozoan calcisponge from the upper Carboniferous of eastern
Nebraska. (Am. Geol., vol. 20, pp. 387-392, pi. 23, Nov. 1897.)
*Thi8 list includes titles of articles received up to the 20th of the precedinir
month, including general geology, phybiography, paleontology, petrology ana
mineralogy.
Authors' Catalogue. 69
Claypole, E. W.
Presidental address. Microscopical light in geological darkness. (25
pp. ; reprinted from Trans. Am. Microscopical Soc, 1897.)
Coleman, A. P.
Third report on the West Ontario gold region. (Ontario Bureau of
Mines, 6th [1896] Rept, pp. 71-124, 1897)
Coleman, A. P.
Anthraxolite or anthracite carbon. (Ontario Bureau of Mines, 6th
[1896] Rept, pp. 159-161, 1897.)
Cross, Whitman.
. An analcite-basalt from Colorado. (Jour, of Geol., vol. 5, pp. 684-
693, Oct.-Nov. 1897.)
Daly, R. A.
Studies on the so-called porphyritic gneiss of New Hampshire.
(Jour, of Geol., vol. 5, pp. 694-722, Oct.-Nov. 1897.)
Davis, W. M.
The Harvard geographical models. (Boston Soc. Nat. Hist., Proc,
vol. 28, no. 4, pp. 85-110, pis. 1-4, July 1897.)
Davis, W. M.
The present trend of geography. (Univ. of the State of N. Y., pp.
192-202, 1897. Paper read June 29, 1897, at the 35th Univ. Convoca-
tion.)
Dawson, G. M.
The physical geography and geology of Canada. (48 pp.; Toronto,
Rowsell and Hutchinson, 1897. Reprinted from the Handbook of
Canada, issued by the publication committee of the local executive of
the British Association.)
Dixon, R. B. (and Drew, C. D.)
Observations on the physiography of western Massachusetts. (Sci-
ence, n. ser., vol. 6, p. 847, Dec. 3, 1897.)
Drew, C D. (Dixon, R. B. and)
Observations on the physiography of western Massachusetts. (Sci-
ence, n. ser., vol. 6, p. 847, Dec. 3, 1897-)
Dumble, E. T.
Some Texas oil horizons. (Texas Acad. Sci., Trans, for 1897, vol.
2, no. I., pp. 87-92, 1897.)
Dumble, E. T.
Texas Permian. (Texas Acad. Sci., Trans, for 1897, vol. 2, no. i,
pp. 93-98, 1897.)
Ellis, W. H.
Chemical composition of the anthraxolite. (Ontario Bureau of
Mines, 6th [1896] Rept, pp. 162-166, 1897.)
Fairchild, H. L.
Glacial geology of western New York. (Geol. Mag., n. ser., dec.
4, vol. 4, pp. 529-537. pl. 21, Dec. 1897.)
70 The American Geologist. January, i898
Fraser, Persifor.
The seventh International Congress of Geologists. (Am. Geol., vol.
20, pp. 409-419, Dec. 1897.)
Frazer, Persifor.
Geological section from Moscow to Siberia and return. (Acad.
Nat. Sci. Phila., Proc. 1897, pp. 405*457, 1897.)
Hill, R. T.
The alleged Jurassic of Texas. A reply to professor Jules Marcou.
(Am. Jour. Sci., ser. 4, vol. 4, pp. 449-469i Dec. 1897.)
Holmes, W. H.
Primitive man in the Delaware valley. (Science, n. sen, vol. 6, pp.
824-829, Dec. 3, 1897.)
Jaggar, T. A., Jr.
A microsclerometer, for determining the hardness of minerals. (Am.
Jour. Sci., ser. 4, vol. 4, pp. 399-412, pi. 12, Dec. 1897.)
James, J. F.
Manual of the paleontology of the Cincinnati group. Part VIII.
(Jour. Cincinnati Soc. Nat. Hist., vol. 19, no. 3, pp. 99-118, Nov. 13,
1897.)
Kunz, G. F.
On the sapphires from Montana, with special reference to those from
Yogo gulch in Fergus county. (Am. Jour. Sci., ser. 4, vol. 4, pp. 417-
420, Dec. 1897.)
Leverett, Frank.
Changes of drainage in southern Ohio. (Bull. Sci. Lab. of Denison
Univ., vol. 9, pt. 2, pp. 18-21, pi. 2, Mch. 1897.) •
Lindahl, Josua.
Description of a Devonian ichthyodorulite, Heteracanthus uddeni, n.
sp., from Buffalo, Iowa. (Jour. Cincinnati Soc. Nat. Hist., vol. 19,
no- 3, pp. 95-98, pi. 6, Nov. 13, 1897)
Logan, W. N.
Some new cirripcd crustaceans from the Niobrara Cretaceous of
Kansas. (Kans. Univ. Quart., vol. 6, pp. 187-189, Oct. 1897.)
Lyman, B. S.
Compass variation affected by geological structure in Bucks and
Montgomery counties, Pa. (5 pp. and map; reprint from Jour. Frank-
lin Inst., vol. 144, Oct. 1897.)
Marsh, O. C.
Recent observations on European dinosaurs. (Am. Jour. Sci., sc-.
4. vol. 4, pp. 413-416, Dec. 1897.)
Martin, D. S.
Excursions of the recent International Geological Congress. (Ap-
pleton's Pop. Sci. Monthly, vol. 52, pp. 228-235, Nov. 1897.)
Osborn, H. F.
Wind River and Bridger beds in the Huerfano Lake basin. (Am.
Nat, vol. 31, pp. 966-968, Nov. 1897.)
Authors' Catalogue, yi
Palache, Chas.
The Geological Congress in Russia. (Am. Nat., vol. 31, pp. 951-960,
Nov. 1897.)
Pirsson, L. V.
On the corundum-bearing rock from Yogo gulch, Montana. (Am.
Jour. Sci., ser. 4, vol. 4, pp. 421-423, Dec. 1897.)
Pratt, J. H.
On the crystallography of the Montana sapphires. (Am. Jour. Sci.,
ser. 4, vol. 4, pp. 424-428, Dec. 1897.)
Prosser, C. S.
The Permian and Upper Carboniferous of southern Kansas. (Kans.
Univ. Quart., vol. 6, pp. 149-175, pls. 18-19, Oct. 1897.)
Sardeson, F. W.
On glacial deposits in the Driftless area. (Am. Geol, vol. 20, pp.
392-403, Dec. 1897.)
Spurr, J. E.
The measurement of faults. (Jour, of Geol., vol. 5, pp. 723-729,
Oct.-Nov. 1897.)
Tight, W. G.
Some preglacial drainage features of southern Ohio. (Bull. Sci..
Lab. of Denison Univ., vol. 9, pt. 2, pp. 22-32, pis. 3 and A-C,
Mch. 1897.)
Tight W. G.
A preglacial valley in Fairfield county [Ohio]. (Bull. Sci. Lab. of
Denison Univ., vol. 9, pt. 2, pp. 33-37, pis. 4 and D-F, Mch. 1897.)
Udden, J. A.
A brief description of the section of Devonian rocks exposed in the
vicinity of Rock Island, Ills., with a statement of the nature of its fish
remains. (Jour . Cincinnati Soc. Nat. Hist., vol. 19, no. 3, pp. 93-95,
Nov. 13, 1897.)
Upham, Warren.
Drumhns containing or lying on modified drift. (Am. Geol., vol.
20, pp. 383-387, Dec. 1897.)
Weller, Stuart.
On the presence of problematic fossil medusae in the Niagara lime-
stone of northern Illinois. (Jour, of Geol., vol. 5, pp. 744-751, i pL,
Oct-Nov. 1897.)
Whiteaves, J. F.
The fossils of the Galena-Trenton and Black River formations of
lake Winnipeg and its vicinity. (Geol. Sur. of Canada, Palaeozoic
Fossils, vol. 3, pt. 3, pp. 129-242, pis. 16-22, Apr. 1897.)
Williston, S. W.
Range and distribution of the mpsasaurs, with remarks on synonymy.
(Kans. Univ. Quart., vol. 6, pp. 177-185, pi. 20, Oct. 1897.)
Williston, S. W.
A new lab^rinthodont from the Kansas Carboniferous. (Kans. Univ.
Quart., vol. 6, pp. 209-210, pi. 21, Oct. 1897.)
^2 The American Geologist. January, vm
CORRESPONDENCE.
The Mechanical Action of the Divining-Rod. The review in
Nature (Oct. 14th, 1897, PP- 5^8, 569) of a publication relating to the
"divining rod" recalls to my mind a purely mechanical theory of that
rod, which was given me years ago by a friend.
This theory has been repeatedly tested by me and shown to be cor-
rect in the presence of my classes. The process is exceedingly simple.
Take any forked twig of reasonably tough fibre in the clenched hands
with the palms upward. The ends of the limbs forming the twig-fork
should enter the closed fist on the exterior side of each fist, i. e., on the
two sides of the clenched hands furtherest from each other.
When a twig is grasped in this position it will remain stationary if
held loosely or with only a moderately firm grasp, but thi moment the
grasp is tightened the pressure on the branches will force the end of
the twig to bend downwards. The harder the grip the more it must
curve.
The curvature of the twig is mechanically caused by the pressure of
the hands forcing the limbs to assume a bent and twisted position ; or
the force that causes the forked limb to turn downwards is furnished by
the muscles of the hands, and not by any other cause.
The whole secret of the divining rod seems to reside in its position in
the hands of the operator, and in his voluntarily or involuntarily in-
creasing the closeness of his grasp on the two ends of the branches
forming the fork.
If the above conditions are fulfilled, the twig will always bend down-
wards — water or no water, mineral or no mineral. Any one can be an
operator, and any material can be used for the instrument, provided the
limbs forming the fork are sufficiently tough and flexible.
It can be easily understood how an ignorant operator may deceive
himself and be perfectly honest in supposing that some occult force, and
not his hands, causes the fork to curve downwards.
Michigan College of Mines, Dec. 8, iBgy. M. E. Wadsworth.
Houghton, Michigan.
PERSONAL AND SCIENTIFIC NEWS.
New York Academy of Sciences, Section of Geology, No-
vember 15th, 1897. — ^^^ first paper of the evening was by Dr.
F. J. H. Merrill, of the State Museum at x\lbany, entitled,
"Geology of the Vicinity of Greater New York."
Dr. Merrill considered the distribution, relations and structure of
the crystalline, metamorphic and intrusive rocks east of the Hudson.
Personal and Scientific News. 73
He noted particularly in the vicinity of New York city the pre-Cam-
brian Fordham gneiss, overlain at certain places, as at Lowerre, Hast-
ings, Sparta and Peekskill by a very thin bed of quartzite, probably
representing the Georgian quartzite of Dutchess county. Above this
is a thick series of crystaUine limestones, forming the valleys of the
Harlem, Bronx and other rivers, and underlying most of the navigable
waterways in the vicinity of New York. The upper rocks are mica-
schists which are probably of Hudson River age, and make most of the
highlands of New York city and vicinity. These rocks are extensively
folded in a general direction of N. 40 E., with occasional cross foldings,
producing the cross valleys. The whole series is crossed by the Man-
hattanville fault, running from Manhattanville, North river, southeast-
wards to the East river, between Ward's and Blackwell's islands, into.
Astoria bay. This fault, along which there has been a throw of a num-
ber of hundred feet, was long ago described by Prof. Dana.
The second paper of the evening was by captain J. J.
Riley, entitled, **The Guano Deposits of the Islands in the
Southern Pacific, and Their Prehistoric Remains." .
Dr. Riley considered in detail the depth, value and manner of work-
ing of the guano deposits in the Chincha islands, of? the southern coast
of Peru, from which guano was first taken by Humboldt in 1804, and
which have since become very famous. Between 1850 and 1880, it is
estimated that guano to the value of 550 million dollars in gold was
taken from three islands alone. The islands lie in the rainless region,
and the preservation of the guano is due to the absence of water. Once
in about seven years there is a season of quite a little rainfall, which
has undoubtedly a great effect upon the guano, and was considered by
Capt. Riley to be the cause of the blacker bands in the layered
deposits. Two burial tombs containing bodies of great antiquity have
been discovered in the guano; the bodies were evidently of royal per-
sonages, and apparently, from the evidences of slabs containing certain
symbols, related to the Incas. These tombs were found at a depth of 35
and 68 feet; but it is not possible to ?tate whether they were buried in
the guano, or later covered by it. The islands, three in number, are
granitic in character, and were covered by a varying thickness of guano,
reaching in the more important island a depth of 203 feet in places.
The exportation of guano has, however, ceased since 1880.
In the discussion, Dr. Julien compared these islands with
other guano-bearing islands of the West Indies, paying par-
ticular attention to the absence of any evidences of human
remains showing life coincident with the formation of the
guano.
The third paper, read by title, was by Mr. Stuart Weller,
and entitled, "A New Crinoid in the Coal Measures of Kan-
sas." Richard E. Dodge Secretary.
A NEW METEORITE. Early in 1897 two pieces of meteoric
iron, weighing sixty-two and fifty-one pounds respectively,
were found three miles northwest of Mungindi postoffice. New
South Wales, but really in Queensland territory. This me-
teorite, which is called the Mungindi meteorite (G. W. Card;
Geol. Sur. N. S. Wales, Records, vol. 5, pt. 3, Sept. 1897),
apparently fell some time ago as in places weathering has
brought out naturally etched Widmanstatten figures. These
74 The American Geologist January, 188K
two pieces of iron are now in the mining and geological mu-
seum of New South Wales.
Rev.Dr. Samuel Haughton, formerly professor of geology
in Trinity College, Dublin, died on Oct. 31.
Hon. Gardiner Greene Hubbard, pres. of the National
Geographic Society, died at his home near Washington on
Dec. II, aged 75 years.
The Minnesota Academy of Natural Sciences held
meetings in celebration of its twenty-fifth anniversary on
Dec. 28, 29 and 30.
Mr. Waldemar LiNDGREN,of the U. S. Geological Survey,
is to deliver a course of lectures on mining and metallurgy
at Stanford University.
Mr. Edgar R. Cummins, of Cornell University, who grad-
uated from Union College last June with honors in geology,
has been appointed instructor in geology in the University of
Indiana. (5c/V«^^.)
Institute of France, Cuvier Prize. — At the session
of the Academic des Sciences held at Paris, Dec. 13, 1897, ^^^
Cuvier prize of 1,500 francs was awarded to professor O. C.
Marsh, of Yale Univcnsity. This prize ^''is awarded everv
three years for the most remarkable work either on the ani-
mal kingdom or on geology."
Rev. Peter Bellinger Brodie, an English geologist^
died on Nov. ist. He early manifested an interest in geolo-
gy, which was fostered at Cambridge, where he studied un-
der Sedgwick. Mr. Brodie was elected a fellow of the Geo-
logical Society of London in 1834 and in 1887 ^^^^ society
conferred upon him the Murchison medal. The November
number of the Geological Magazine contains a sketch (with
portrait) of Mr. Brodie, written shortly before his death.
The Iowa Academy of Sciences held its twelfth annual
meeting at Des Moines on December 27 and 28. The follow-
ing geological papers were presented:
Is the loess of aqueous origin? B. Shimek.
The degradation of the loess. J. E. Todd.
Sketch of the hvdrographic history of South Dakota. J. E. Todd..
Carboniferous formation of the Ozark region. C: R. Keyes.
Geographic de\'^lopment of the Crimea. C. R. Keyes.
Some geological features of the Cap au Gres region. C. R. Keyes.
Some anomalous valleys and paradoxical divides in Delaware county^
Iowa. Samuel Calvin.
Interglacial deposits of northwestern Iowa. Samuel Calvin.
The buried soil between the Iowa loess and the Illinois till sheet.
Frank Leverett.
Aftonian deposits of southwestern Iowa. H. F. Bain.
Preglacial peat beds. J. A. Udden.
The drift section and the glacial striae in the vicinity of Lamoni. T.
J. Fitzpatrick.
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Fairbanks, H. W.
Oscillations of the coast of California during the Pliocene and Pleis-
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I
THE
AMERICAN GEOLOGIST
Vol. XXI. FEBRUARY, 1898. • No. 2
ADDITIONAL NOTE ON THE OCEANIC CURRENT
IN THE UTICA EPOCH.
By R. RuEDEHANN, Dolgeville, N. Y.
(Plate IX.)
In an article, published in the June (1897) number of this
journal,* the writer described a series of observations which
led him to suppose the existence of an ocean current in the
Utica epoch in the south and southwest of the Archaean mass
of the Adirondacks. The evidence of the oceanic motion con-
sists mainly in the parallel arrangement of graptolites and
cephalopods in a NE-SW direction in the Utica shale, in
outcrops occurring in the Mohawk valley and on Nine-Mile
creek, north of Utica.t The observed directions in the last
locality, which is southwest of the crystalline area, necessitate
the assumption that the southern part of the latter was a pene-
plain, which was swept by the current, and that the mantle of
Utica shale formely extended considerably farther north than
it does at present.
C. D. Walcott reached the conclusion before, that the
Cambrian-Ordovician sea spread over the Adirondack crys-
tallines, depositing a mantle of sediments. This supposition is
illustrated by an ideal section (p. 25), in explanation of which
is said:
*Vol. XIX, No. 6, p. 367.
tCf. the sketch map, op. cit. pi. XXII.
^Second Contribution to the Studies on the Crimbrian Faunas of
North America, Bull, of the U. S. Geol. Survey, No. 30, 1886, p. 24.
76 The American Geologist. FL-bmary, x'im
"The view expressed by the section is that there was a practically
conformable deposition of sediments, against and over the Archaean
area of the Adirondack mountains, from early Cambrian times up to the
close of the deposition of the sediment forming the Utica shale, except
in the case of the unconformity by non-deposition between the Potsdam
and the Chazy. The writer has seen the deposition contact of the Utica
shale, against the granite, on the eastern side of the Adirondack moun-
tains, in Essex county. New York, and takes that as the upper line of
the ideal section, although he has little doubt that the formations over-
lying the Utica shale, even through the Silurian, were deposited against
and over the Archaean of the Adirondacks and subsequently removed
by denudation."
Lately a somewhat different view regarding the relation of
the sedimentary covering to the underlying crystallines has
been advanced by J. F. Kemp.*
A careful study of the topography and geology of the out-
liers in the eastern Adirondacks led Mr. Kemp to the con-
clusion that the Palaeozoic rocks — Potsdam sandstone and
Calciferous limestone at present, and also Trenton and Utica
beds formerly, as Mr. Kemp supposes — were deposited in pre-
existing valleys, which had been formed when, in the early
Cambrian, the Adirondack hight -of-land must have been sub-
jected to the ordinary processes of erosion and land sculpture.
Mr. Kemp admits that faulting no doubt plays a considerable
part in many of the outliers, but, at the same time, calls atten-
tion to the fact that some of the present streams, connected
with the outliers show often very low gradients for Adiron-
dack creeks and appear to be near local base levels. It is sup-
posed that the post-palaeozoic erosion, as well as the great
ice-sheet, were active in clearing the valleys of the Cambrian
and Ordovician sediments, and in reducing them to their pre-
Cambrian gradients.
Special attention is also called in Mr. Kemp's interesting
paper to the outlier of Palaeozoic rocks at Wellstown, on the
Sacandaga rivcr.t As this remarkable outlier, which consists
of Potsdam, Calciferous, Trenton and Utica beds, lies directly
in the path of the current which produced the parallel arrange-
*J. Y. Kemp. Physiography of the eastern Adirondacks in the
Cambrian and Ordovician times. Bull. Geol. Soc. Am., Vol. VIII, p.
408, i8g6, and J. F. Kemp. The Pre-Cambrian Topography of the
Eastern Adirondacks. read at the Washington meeting of the Geol.
Soc. Amor.; Abstract in Jour. Geol., Vol. V, No. i, p. loi, 1897.
tSee the map: Am. Geol., Vol. XIX, No. 6, pi. XX 11.
Oceanic Current in tJie Utica Epoch. — Ruedemann, jy
ment of the fossils on Nine-Mile creek, the writer had made
use of its existence to prove the submergence of the southern
Adirondacks in the Utica epoch. It is evident that if this out-
lier is only to be regardetl as the remnant of a deposit in a
drowned valley, the assumption of the passing of a current
across the Adirondacks as far north as Trenton Falls, is not
justified.
The outlier at Wellstown, which had been discovered and
described by Vanuxem in 1842, has been lately described more
fully by N. H. Darton.* It appears from the latter investi-
gator's description, that "the area of Palaeozoic rocks was
found lying against a fault scarp on its western side, and pos-
sibly faulted on the east side also," and that the Potsdam, Cal-
ciferous, Trenton and Utica formations have their usual char-
acteristics, and the latter two, their usual faunas. Thus, the
interesting fact that four different beds belonging to different
periods occur in the same small outlier, in a remote place in
the Adirondacks, is rendered still more remarkable by the
observation that all these beds apparently differ in no way
from the continuous terranes along the southern border of the
Archaean area. These remarkable features of the outlier and
the importance of the knowledge of its origin for the writer's
views on current action in the Utica epoch, induced him to
visit the locality.
The outlier was found to form an oblong plain surrrounded
on all sides by steeply rising ridges of crystalline rocks. The
fault-scarp at the west side is distinct, the Archaean rocks ris-
ing steeply 1,300 feet above the Potsdam level. As also on the
east sidt", the Archaean hills present a steeper slope than the
but slightly tilted Palaeozoic rocks which outcrop at their base,
the existence of a fault is very probable also on this side. The
whole outlier, therefore, seems to be the remnant of a fault-
valley or "graben.'' This fault-valley has, however, been
formed after the deposition of the Palaeozoic strata, and served
only to protect them from the destructive effects of the atmos-
phere and of glaciers. Originally, the beds belonged to a con-
tinuous mantle of Palaeozoic strata, which covered the south-
* Geology of the Mohawk Valley, Rept. of N. Y. State Geologist for
1893, pp. 414 and 429. See also: A Preliminary Description of the
Faulted Region of Herkimer, Fulton, Montgorvery and Saratoga
Counties. Kept, of N. V. State Geol. for 1894, p. 47.
78 The American Geologist. Februan-, i898
ern flank of the Archaean mass. The main argument for this
supposition is that the Potsdam, Calciferous, Trenton and
Utica form^ations, are developed here in a like manner as the
respective strata which, in the south, strike continuously along
the foot of the Adirondacks. The Potsdam — consisting of a
rusty weathering, not very coarse grained, somewhat calcare-
ous sandstone, that alternates with lighter colored beds — and
the light-colored arenaceous limestone that represents the Cal-
ciferous, differ in no way from the outcrops in the Mohawk
valley. The Utica shale, which is well exposed in a pit for
breaking road-metal, and which outcrops in a neighboring
rivulet in several places, is the typical, fine-grained, often
fissile black shale of the lower part of the formation and con-
tains scattered specimens of Diplograptus foliaceus Murch.
(=z pristis Hall). A slab in the ravine contained a greater
number of these graptolites, which were arranged between
N 50 degrees E and N 90 degrees E. In slabs found on a
road, fragments of Endoceras and casts, probably belonging
to a Modiolopsis, were met with. Neither does the light-gray,
highly fossiliferous limestone, which, for many years, has been
used for lime-burning, differ from the Trenton in the Mohawk
valley. The only remarkable feature is a bed which contains
round pebbles of a few inches diameter, and which are derived
from a lower part of the limestone. But such conglomerates
occur even much farther south in the Trenton. They are of
general interest, as the Trenton limestone has been often
regarded,* and not without good reason, as a deep-water de-
posit. A very interesting occurrence of conglomerate in the
Trenton was iound by the writer at Ingham's Mills, on East
Canada creek, in ah exposure, which has been made known
bv X. II. Darton.t
The slaty intercalation in the upper eight feet of thin-
bedded limestone, near the top of the section, was here found
to contain water-worn, rounded, flat boulders,t which reach a
diameter of several feet and are derived from the light-colored
compact layers below the typical Birdseye limestone. As the
*Compare for instance Lapworth, Trans. Roy. Soc. Can. for 1886,
V, Sec. IV, p. 176-
tGeology of the Mohawk Valley, Rept. of N. Y. State Geologist
for 1893, p. 422.
tSee Plate IX, fig. 2.
Oceanic Current in the Utica Epoch. — Ruedematm. 79
pebbles at Wellstown and at Ingham's Mills consist only of
limestone, and not of crystalline rocks thev indicate but a
temporary recession in the Trenton epoch, during which some
of the lower limestone was worked up. It is, however, re-
markable that this limestone had already hardened.
The conclusion to be drawn from the comparison of the
four Palaeozoic terranes at Wellstown, and in the lower Mo-
hawk valley, is that equal conditions existed at both places
during each of the four periods. The deposits in the Mohawk
valley are evidently those of an open, unbroken seacoast, and
it is a recognized fact that different sediments are deposited in
embayments and in the open sea. The exceptional case of
the deep fjords of Norway, which partly show the fauna and
deposits of the deeper part of the North sea off the coast of
Norway, can hardly be adduced here. Moreover, it can hardly
he assumed that the successive changes in character of sedi-
ment, taking place from the Potsdam through the Calciferous
and Trenton to the Utica formations, should have been ex-
actly repeated in a bay which, being formed by the drowning
of a valley, could not have been very wide, and, lastly, it must
be expected that the upper course of the Sacandaga river,
which emptied in that bay, would have filled it with deposits
of crystalline origin.
The writer's view, that the Utica shale at Wellstown is only
a remnant of a once continuous covering of the southern
Adirondacks, seems also to be supported by the great number
of fragments of Utica shale and the great quantities of dark
clay with included shale in the glacial drift on the southern
slope of the Adirondacks. The amount of this drift would
seem to indicate the scouring away and working up of more
shale than the valley deposits could have furnished, and it
can hardly be assumed that the fissile, easily ground shale
could have been brought from the northeast and carried over
the Archaean area.
All these conclusions refer only to the outlier at Wells-
town and to the southern slope of the Adirondacks, those in
the east of this plateau not being known to me.
The writer embraces this occasion to correct an oversight,
committed in the first paper on current action, by not men-
tioning the interesting conclusions of G. F. Matthew on the
8o Jlic American Geologist. February. i«»*
distribution of animals in Cambrian and Ordovician times.
Mr. Matthew,*in an address on the "^Diff usion and Sequence of
the Cambrian Faunas," comments upon the deep-sea charac-
ter of the various graptolitic faunas, as expressed in the com-
position of graptolites, Triarthrus, deep-water sponges, and
brachiopods. The graptolitic faunas are enumerated, the last
being that of the Utica slate. In reference to this is related
that after the irruption of the Arenig fauna and the following
restoration to more genial conditions in the beginning of the
Trenton period, a new fauna invaded the territory held in the
east by the Trenton fauna, that of the Utica slate. This fauna
succeeded in extending itself further west than its predeces-
sors of the Atlantic coast containing graptolites. Besides oc-
cupying the St. Lawrence valley, it was spread westward
across the provinces of Quebec and Ontario, and southward
through New York and Pennsylvania. In contrasting the
slow migration of shallow water forms with that of the inhab-
itants of the deeper and colder sea, the following statement is
made: "No sooner do the latter appear in Europe than al-
most simultaneously we find them (or species closely related
to them) on the Atlantic coast of the new world." This im-
plies the assumption of a migration of the deep-water forms^
characteristic of the Utica shale, from Europe to North
America.
The same idea is still farther developed in another ad-
dress,f in which Mi*. Matthew contrasts the faunas of the
warm and shallow water with those of*the colder and deeper
water, and concludes that the coralline limestones represent
the preponderance of w^arm shallow water, the graptolitic
mud deposits representing the deeper and colder parts of the
ocean. Applying this principle to the succession of calcareous
terranes, containing corals and large mollusks, and of the dif-
ferent graptolitic shaly terranes of the North American Cam-
brian and Ordovician, Mr. Matthew concludes that this suc-
cession was caused by alternating incursions of deep cold
water faunas from Europe, and of warm shallow water faunas
. from the American Mediterranean sea. Two sketch maps-
*Published in: Trans. Roy. Soc. Canada, Vol. X, Sec. IV, 1892. p. 3.
tThe Climate of Acadia in the Earliest Times. Annual Address.
Bull. Nat. Hist. Soc. New Brunswick, No. XI, 1893, p. 3^.
Shell-Bearing Drift on Moel Try fan.. — Upham, 8i
serve to illustrate these successive arrivals of faunas of diiTer-
ent origin in the northeast of North America.
While thus the Trenton contained a warm water fauna,
which had its origin in the southwest, the Utica fauna was
borne to us on the cold current from north Europe, where it
probably had its fountain-head, as the Paradoxides and Arcni«^
faunas had before. It is obvious that these interesting con-
clusions of Mr. Matthew as to the origin of the Utica fauna
find a verification in the writer's observations on the exist-
ence of an ocean current passing from northeast to southwest
along the south slope of the Adirondack Archaean area in the
Utica epoch. The writer had supposed that this current had
taken the course of the present Labrador current, and fol-
lowed the east coast of the Laurentian continental nucleus of
Canada.
EXPLANATION OF PLATE.
Fig. I. Section at Ingham's Mills:
(a). Eight feet of Trenton limestone and intercalated slate, the
latter containing limestone bowlders.
(b). Typical Birdseye limestone, the vertical columnar fucoidal
stems, producing the birds' eyes on the bedding planes, are visible on
the photograph.
Fig. 2. Conglomerate, showing the contorted shale and the im-
bedded limestone bowlders.
[European ant] Amorican Glacial GcoluKy C^tmpurorl. I.]
SHELL-BEARING DRIFT ON MOEL TRYPAN.
By Warken Uph.am, St. Paul, Miun.
This series of short papers is designed to describe briefly the
glacial geology of some important or especially interesting
European areas, or localities, examined by the writer during
the summier of 1897, and to compare them with similar Ameri-
can glacial observations and theories.
Landing in Southampton June 2nd, our party, including
also my wife and a lady friend, spent the next eight days in
London, Oxford, and Stratford-on-Avon. June nth we went
onward by way of Chester, the north shore of Wales, and Car- *
narvon, to Llanberis, a pretty village in a very picturesque
valle}' at the north base of the craggy, sharp-peaked Snowdon
82 The American Geologist. February, i898
and the rounded, grassy Moel Eilio (2,382 feet). The next
day we ascended Snowdon by its railway, rising from the
lakes of Llanberis (400 feet above the sea) to the highest sum-
mit of southern Britain, 3,570 feet above the sea. Around us,
on all sides excepting northwestward, were the steep, mostly
rugged and boldly serrate Welsh mountains, consisting of the
very ancient Cambrian rocks.
Moel Try fan (or Tryfaen), the hill which for that day was
my desired destination, lay in plain view at a distance of six
miles westward, beyond a deep valley in which we saw the
Cwellyn lake (about 500 feet above the sea) and the Snowdon
Ranger inn, with its group of Scotch pines. Toward the drift
sections displayed in the slate quarrying near the top of that
hill, visited and much discussed by many geologists during
the past sixty years, I walked down the stony path to the inn,
past the lake, beneath the northern precipice of a spur of
Mynydd Mawr, and up the drift-covered, smooth and pas-
tured ascent of Moel Tryfan. Looking back, I saw a cloud
bank enveloping the top of Snowdon and towering above to a
great altitude, though elsewhere the air and sky were mostly
clear.
The area occupied by Moel Tryfan is about a mile in
diameter. Its slopes, of moderate steepness, are almost wholly
covered by till, with frequent or abundant boulders, beneath
which, at the quarries, are extensive deposits of gravel and
sand. At shallow depths the slate is reached and quarried;
and at the summit a jagged mass of conglomerate juts up
about 15 feet above the surrounding grassy pasture. The
hight of this point is given on the Ordnance Survey map as
1,399 feet above the sea. The highest col dividing this hill
from the neighboring mountains is on the southeast, at a dis-
tance of about a mile, having an estimated altitude of about
1,150 feet, whence the next mile eastward rises to the crest of
Mynydd Mawr, at 2,290 feet. On the southwest and thence
around to the north, all the country is much lower than our
hill, and is a fine agricultural district, with the little seaport
city of Carnarvon well seen four miles northwest.
In 183 1, Trimmer discovered fragmentary marine shells
in the sand and gravel under the superficial boulders and till
at the slate quarries near the top of Moel Tryfan; and by sub-
Shell-Bearifig Drift ofi Mod Try fan. — Upham, 83
sequent collectors about 60 marine species have been found
in these sections, from about 1,275 to 1,360 feet above the sea,
including 27 lamellibranchs, 26 gastropods, two species of
Dentalium, two of barnacles, one Serpula, and two species of
the shell-burrowing sponge, Cliona.* In 1842, Darwin ob-
served that the underlying slate, "to a depth of several feet,
had been shattered and contorted in a very peculiar manner."
In 1863, Lyell noted that he saw in the lower beds of the shell-
be^fing sand and gravel several large boulders of far-trans-
ported rocks glacially polished and scratched.
Among the great number of geologists who have treated
more or less fully of this fossiliferous drift we may further
especially mention Reade,f Shone,J Mackintosh§ aud Stra-
han. I All these authors refer the deposition of the shell-
bearing stratified drift to marine action during a time when
northern Wales, with Cheshire, Lancashire, and other parts
of northwestern England, and a part of Ireland, near Dublin,
if not much greater areas, suffered a depression of 1,000 to
1,360 feet or more. In these districts various localities have
been discovered where fragments of marine shells occur in
the modified drift up to these altitudes, their maximum hight
being on Moel Try fan.
Other geologists, as Belt and Goodchild in 1874, H. Car-
vill Lewis in 1886, and Percy F. Kendajl in 1892, have at-
tributed these shell-bearing beds to deposition from the
streams of the melting British ice-sheet, while the land here
stood at nearly its present level, during the Champlain or
closing epoch of the Glacial period, ^f This view seems to me
♦J. Gwyn Jeffries. Quart. Jour. Geol. Soc, XXXVI (1880), 351-355-
T. McKenny Hughes, in the same Journal, XLII (1887), 87-97, gives
tabular enumerations of the marine fossils in the drift, of Moel Tryfan
(66 species) and of numerous other localities and districts of northern
Wales and northwestern and northeastern England, with bibliography.
tQ. J. G. S., XXX (1874), 27-42; XXXIX (1883), 83-132. Proc,
Liverpool Geol. .oc, 1892-93, pp. 36-79, with eight plates (maps and
sections) and a bibliography.
tQ. J. G. S., XXXIV (1878), 383-397.
§ld., XXXVII (1881), 351-369; XXXVIII (1882), 184-196.
i'ld., XLII (1886), 369-391 [abstract in Geol. Mag., third series, III,
(1886), 331-333].
1[See the present writer's sketch of "Prof, Henry Carvill Lewis and
his Work in Glacial Geology," Am. Geologist, II, 371-379, Dec, 1888;
and Kendall's admirable summary of the glacial geology of England
and Wales, in Wright's **Man and the Glacial Period," 1^2, pp 137-181,
with maps and sections.
84 The Americaft Geologist. February, i898
the true explanation. It regards the shell fragments as de-
rived by glacial transportation from the area of the Irish sea,
by an ice-sheet flowing southward from southwestern Scot-
land, northwestern England, and northeastern Ireland^ by
which the early Pleistocene beds of that sea basin were plowed
up and mingled with boulders from the more distant nrffch-
ern tracts of thick ice accumulation. Many of the boufders,
with much finer drift, were derived from mountains high
above the old sea bed; but I think that drift from all these
sources, both high and low, was intermingled in the l(^er
part of the moving ice-sheet, up to bights of probably i,ooo to
1,500 feet in the ice, and yielded to the streams of its final
melting the shell-bearing gravel and sand of these high levels,
as also of lower tracts down to the present coast lines.
Jeffreys states that eleven species of the Moel Tryfan
marine shells are arctic or northern, of which eight now range
no farther south than the coasts of Norway, there living at
depths of from 10 to 20 fathoms; but that the other species (a
large majority of the whole) are littoral or live in shallow
water, all of these being probably now inhabitants of the
neighboring Carnarvon bay.
With slight search I found in the sand and gravel on the
northwest side of the Alexandra slate quarry, about 50 feet
below the rock peak of Moel Tryfan, many minute particles of
shells, from the size of a pinhead to an eighth or a quarter of
an inch, and a few larger fragments, referred to three species,
as determined by Prof. Kendall, namely Leda pernula Miiller,
Tellina balthica L., and Fusus antiquus L., the last having its
Pleistocene dextral form, distinguished thus from its uniformly
sinistral Pliocene form.
The Alexandra quarry, about 30 rods in diameter, having
a depth of 75 feet or more below the lowest northeastern part
of its rim and fully 150 feet below the high western part of the
rim, is situated about an eighth of a mile east from the sum-
mit of Moel TrN'fan which rises some 40 feet above the high-
est part of the brink of this quarry. The eastern half of the
rim or brink has much till, to the depth of 10 to 15 feet, in-
closing plentiful boulders up to five feet and rarely ten feet
in diameter. Beneath this till on the southeast are a few feet
of very irregularly stratified and contorted sand and gravel,
Shell-Bearing Drift on Moel Try fan. — Upham. 85
which at the northeast increase • to a thickness of about ten
feet. Proceeding thence westward along the north rim of the
quarry, the till gradually thins to only two or three feet, while
the sand and gravel continue from 10 to 15 feet thick upon the
rising slope of the slate. Along the western and southwestern
sides the drift capping the vertical quarry walls maintains a
thickness of from 12 to 18 feet, and is almost wholly sand and
gravel, often contorted in bedding, with occasional stones up
to a foot in diameter, especially in the upper one to four feet,
while the adjoining surface bears frequent boulders.
Another quarry, of similar area and depth, has its northern
brink only 40 feet south of the southern brink of the foregoing.
Its slate is overlain around all its extent by 5 to 15 feet of
drift, thickest at the northeast. This drift has mainly the
stratification and other characters noted on the western half
of the Alexandra quarry; but it includes, on the northeast, a
thickness of several feet of overlying till. Superficial boulders
are seen here and there on all the surrounding pasture land.
From my studies of the till of drumlins in and adjoininjjf
Boston harbor, containing plentiful fragments of marine shells
which represent 55 species, all now living on our coast, but
some having mainly a southern range,* and from my discov-
ery of similar shell fragments in the modified drift forming
Cape Codjt I conclude that the modified drift and worn and
broken marine shells of Mbel Tryfan were supplied by the
melting of the southern border of the principal British ice-
sheet. In its maximum extent, that ice flow from the north
abutted against local icefields that flowed outward from the
Snowdonia mountain region. Their line or belt of junction
appears to have crossed Moel Tryfan, and eastward to have
passed over Fridd Bryn Mawr, which extends north from
Moel Eilio along the west side of Llanberis and lake Pa darn.
On this Bryn Mawr, at the hight of about 1,000 feet above
the sea, Ramsay found marine shell fragments in the drift.
More explicitly to indicate the conditions which seem to
me to have attended the deposition of the Moel Tryfan sand
♦Proc, Boston Soc. Nat. Hist, XXIV, 127-141, Dec, 1888 (also in
Am. Jour. Sci., Ill, XXXVII, May, 1889). W. O. Crosby and H. O.
Ballard, Am. Jour. Sci., Ill, XLVIII, 486-496, Dec, 1894.
tAm. Naturalist, XIII, 489-502, 552-565, Aug. and Sept., 1879.
86 The American Geologist, February, lies
and gravel and the overlying till, I can do no better than to
refer to my paper in the last number of this magazine, and to
my description there cited of the occurrence of abundant
stratified deposits under till in the basin of Lake Winnipesau-
kee in New Hampshire.* On Moel Tryfan free drainage
carried away the clay and fine silt that were supplied to the
waters of the glacial melting, and these waters appear to me to
have deposited subglacially the shell-bearing gravel and sand,
while the almost contemporaneous till was allowed to fall
from its previously englacial and superglacial position when
the ice was fully melted away.
The contour and surface deposits of this hill have no feat-
ures which I can regard as suggestive of shore lines or of
marine deposition or erosion.
COTE SANS DESSEIN AND GRAND TOWER.
By C. F. Marbut, Columbia, Mo.
(Plate X.)
Cote Sans Dessein is a narrow isolated ridge of paleozoic
rocks rising steeply from the level of the flood plain of the
Missouri river in the southeastern part of Callaway county,
Missouri. It is about a mile long, 200 feet wide and rises 100
feet above the level of the flood-plain. The latter, at this place,
is about two miles wide, and Cote Sans Dessein stands about
midwav between the northern and southern bluffs.
It is made up of horizontal beds of magnesian limestone,
identical in age, structure and lithologic character with those
outcropping in the bluffs on both sides of the flood-plain in
the vicinity. The Missouri river now flows between Cote Sans
Dessein and the southern border of the floodplain and has
occupied this position continuously since the occupation of
the region by white men; but the broad belt of typical flood-
plain lying to the north of the hill is positive evidence that
the river has recently occupied that belt.
Grand Tower is another hill whose relations to the flood-
plain of the Mississippi river are apparently the same as those
♦Am. Geologist, XX, 383-387, Dec, 1897. Geol. of N. H., Vol. Ill,
1878, pp. 131-137.
Thk Amebican Geologist, Vol. XXI.
Plate X.
Cote Sans Dessein and Grand Tower — MarbuL 87
of Cote Sans Dessein to the Missouri river flood-plain. It is
situated in Jackson county, Illinois, about 30 miles below
Chester and about the same distance above Cape Girardeau.
Like Cote Sans Dessein it is an isolated hill made up of beds
of paleozoic rocks identical in age, structure and character
with those exposed in the bluffs on both sides of the flood-
plain. It .rises abruptly above the flood-plain to a hight of
fully 100 feet. It is accompanied by an unnamed companion,
of about equal size and identical relations to surroundings,
which lies about a mile to the north. Grand Tower differs
from Cote Sans Dessein, however, in its position within the
flood-plain. That part of the plain lying between Grand
Tower and its eastern bluff is nearly five miles wide, while
that part lying west of Grand Tower is less than two miles in
width. The river at the present time occupies the belt be-
tween Grand Tower and the western bluff.
These features are members of a rather large group of
liills, occurring in many parts of the world, which are more
or less closely related to each other in origin. The greater
number of them, however, are surrounded by narrow winding
belts of lowland, while the two under consideration rise from
the midst of wide lowlands. The origin- of the former is now
well understood and they have been described from many
parts of the world.* They are known to be the result of the
formation of cutoffs in upland meandering streams and are
the homologues of the lands surrounded by crescentic lakes
so common in the flood-plains of many large rivers. Hills of
this kind occur in Missouri, but so far as nOw known they
are confined to the streams of the Ozark region. They are
known to occur on the Meramec, Bourbeuse, Grand and Gas-
conade rivers and on many small creeks. They do not occur
on either the Missouri, Mississippi or the Osage. In Europe
they are of frequent occurrence, especially in the Ardennes
region of Belgium, the lower Seine region in France and in
central Russia.
Cote Sans Dessein and Grand Tower show no evidence of
such an origin. In fact, in the case of the former, the evidence
of origin by different, though related process is clear. Its re-
*Natl. Geographic Magazine, June and July, 1896.
88 The American Geologist, February, i898
lation to the Missouri and Osage rivers shows that it is an out-
lying remnant of the upland lying between the Osage and
Missouri rivers. The Osage originally entered the Missouri
below the lower end of Cote Sans Dessein. Subsequently, by
the combined sapping of both the Missouri and Osage rivers
on opposite sides of this upland it was cut through above
Cote SanS Dessein. At that time or later the Missouri appro-
priated the lower part of the old Osage valley. Since doing
this it has doubtless widened this belt so that it is now as
wide as the old Missouri valley north of the hill. Cote Sans
Dessein lies directly in the line of prolongation of this upland
where it still exists. The meander system of both the Osage
and Missouri rivers shows also that the point where the up-
land was cut was exposed to the vigorous sapping of both
streams, being on the convex sides of meanders in both
streams. Cote Sans Dessein stands where the meandering of
the Osage at least carried the point of active sapping to the
southern side of the valley.
Grand Tower maintains the same relation to the Missis-
sippi and Big Muddy rivers that Cote Sans Dessein main-
tains to the Osage and Missouri. It is not so clearly due to
this relation, however^ as is Cote Sans Dessein. There is a
very great difference in size between the Mississippi and Big
Muddy. The latter is much smaller than the Osage, but that
part of the flood-plain lying on the Big Muddy side of Grand
Tower is much wider than the other. It may be true that the
Mississippi was diverted to the Big Muddy valley soon after
reaching grade and remained in that position until recently.
The explanation of its existence is based wholly on its position
with respect to the two streams.
The same processes have been operating in at least two
other places ift Missouri. One place is in the vicinity of the
mouth of Moreau river, which flows into the Missouri about
four miles above the mouth of the Osage. The Moreau was
originally tributary to the Osage, entering the latter stream
near the Missouri Pacific railway bridge. From that point
up to its present mouth its general course was parallel to that
of the Missouri, but instead of taking this course in a direct
line it meandered over a belt more than a mile in width. Its
own action on the convex side of the meanders combined with
Cote Sam Dessein and Grand Tower. — Marbtit. 89
the southward sapping of the Missouri, finally cut through
the upland between the two streams, at a point about two
miles above its old mouth. It then flowed into the Missouri
and abandoned the lower part of its old valley. The Missouri
river has never occupied this old valley as it has the old Osage
valley south of Cote Sans Dessein. At a later period the
Moreau again cut through the intervening highland between
its valley and that of the Missouri and now enters that stream
a little more than a mile above the first cut. At this point, how-
ever, the Moreau did not cut directly through the upland and
into the Missouri flood-plain, but cut into and occupied the
lower part of the valley of a small tributary of the Missouri.
The tributary did not flow at right angles to the course of
either the Missouri or the Moreau, but at a rather low angle
with the latter for several hundred feet on each side of the
point of capture. The Moreau began by capturing the head-
waters of the small stream. It continued to invade more and
more of the valley of the small stream until it had reached a
point where the level of the latter was the same as that of the
Moreau. The valley of the small stream was occupied and
the Moreau abandoned another section of its former vallev.
There can be no doubt that the abandoned valley is that of
the Moreau. It is continuous with the present valley and of
about the same width. The meanders of the old valley fit onto
those of the Moreau, and the* character of the meanders is the
same in both cases. The Moreau is characterized by long
swinging meanders with narrow belts of upland between, and
a meander belt more than a mile in width.
Another repetition of the same features occurs in Benton
county. Grand river, which flows into the Osage about three
miles above Warsaw is a stream whose lower course, that
through the lower Carboniferous and Silurian limestones, is
very much like that of the Moreau. The present mouth of
Grand river is the homologue of that of the Moreau after the
first and before the second capture. In this case, however,
the Osage river, the larger stream, did a relatively larger part
of the work than did the Missouri in the other. Before this
capture Grand river flowed into the Osage about three miles
below the present site of Warsaw. As in the case of the
Moreau, the character of the abandoned part of Grand river
valley leaves no doubt of its orij^in and for the same reasons.
go The Amefican Geologist, February, 1888
Little Tebo creek, which was formerly tributary to Grand
river, now flows into the Osage, reaching the latter by flowing
up the abandoned valley for about a mile and a half. Another
small stream, formerly tributary to Grand river at a point
about two miles below the old mouth of Little Tebo, is now a
tributary of the latter, turning up the old valley rather than
down it. This stream could reach the Osage in just about the
same distance that is now flows to reach it, by turning down
the old valley.
THE GEOLOGY OF THE KEWEENAWAN AREA IN
NORTHEASTERN MINNESOTA.
By A. H. ET.FTMAN, Minneapolis.
(Plate XI.)
SYNOPSIS.
Part I.— Glacial Geology.
Goiieral statement, moraines, uon-morainic till, modificnl drift, wind deposits
di.stribution of bouldera, glacial Htriee, glacial lake»> and rivers, glacial
eroi«iun.
Part 11,— GeoUtgy of ike Keweenawan Series.
OhapttM* 1.— Stratigraphy.
1. Historical review.
2. Results of the present investigation.
Chapter II.— Faulting in the Keweenawan Sorien.
f'hapter III.— The Gabbro Group.
Surface area, age, structure, differentiation varieties, niincral and chemi-
cal composition, contact phenomena.
(Uiapter IV.— The Beaver Bay Diabase Group.
1. Diabase, diabase porphy rite, etc.
2. Anorthosytes of the north shore of lake Suijorior.
8. Fragmental rocks.
Chapter V.— The Red Rock Group.
1. Intrusive ; granite and augite syenite.
2. Surface flows ; quartz- porphyry, aporhyolite.
Clinptc-r VI.— The Temperance River Group.
1. Unconformity.
2. Surface flows; diabase, etc.
H. Intrusive,
4. Sedimentary ; conglomerate, sandstone, etc.
Clmpt<'r VII.— The Later Diabase Group.
Dikes, sills,' breccia.
Chapter VIII.— Summary and discussion.
The Keiveenawan in Minnesota. — Elfttnan, 91
PART I.
' GLACIAL GEOLOGY.
General Statement. — Certain important features of the gla-
cial geology of northeastern Minnesota are found within the
areal limits of the Keweenawan series. The glacial drift oc-
curs in: ist, well defined moraines; 2nd, rolling till, and 3rd,
modified deposits. The chief moraines are limited to the cen-
tral part of this region, extending from Pigeon river to Saint
Louis river, with the northern and southern boundaries of the
morainic area equi-distant between the international bound-
ary and lake Superior. The till and modified drift is abund-
ant, and hence in this area the underlying rock is for the most
part concealed, appearing only in isolated outcrops often sev-
eral miles apart. In the rest of the region the drift is either
present in small quantities occupying the depressions and cov-
ering the rocks with a thin veneer only, or it is entirely want-
ing. The drift of northeastern Minnesota is regarded as
belonging to the Wisconsin stage of the Glacial Epoch.
MORAINES.
Mr. Warren Upham has mapped the moraines of northern
Minnesota in the twenty-second annual report of the Minne-
sota Geological and Natural History Survey, plate I. In that
portion of the state north of lake Superior widely separated
known areas of moraihic drift were provisionally correlated
by Mr. Upham with the Leaf Hills, Itasca, Mesabi and Ver-
milion moraines found in the central and western parts of the
state. The moraines thus mapped extend in a general east
and west direction across Minnesota and appear to have been
formed successively during a movement of the ice sheet prin-
cipally from the north.
Prof. J. E. Todd has called attention to several objections
to this interpretation;* namely, that the interpretation of Mr.
Upham does not duly recognize the altitude and that it does
not represent the ice sheet as retiring in the proper direction
to explain the formation of Western Superior glacial lake,
and that it does not agree with the direction of the striae and
♦Revision of the moraines in central Minnesota. Amkr. Geol., vol.
XVIII, 1896, pp. 225-226.
92 The Americaii Geologist, February, i898
•
of. the distribution of boulders. In view of these and other
facts the moraines in north central Minnesota are "referred to
two great lobes of the ancient ice sheet, a shorter one moving
southwest through the lake Superior basin and a longer one
moving around this from the northeast to the west and south-
west. In their recession, these lobes formed successive slen-
der and more or less curved reeentrant angles producing in-
terlobate moraines, one arm of each being formed on the west
side of the lake Superior lobe, and the other arm along the
east side of the Red River lobe. The apex of this angle
advanced toward the northeast until it grew into a slender
moraine probably traceable along the Mesabi Range."
Professor Todd's objections against the previous arrange-
ment of these moraines seem well founded. The lobate char-
acter of the ice sheet during its last stage of existence in
northeastern Minnesota is evident.
The accompanying map (plate XI ) showing the glacial
geology of northeastern Minnesota is intended to emphasize
the relation of the moraines. For the region west of Range
II, west of the 4th principal meridian the map and descrip-
tion accompanying it are taken from Mr. Upham's report
already cited. For the region east of range 12, the descrip-
tions are based almost entirely upon the writer's observations.
The morainic belts represented upon the map, approxi-
mately outline the very rough drift accumulations character-
ized by numerous kettle holes. Since the moraine immedi-
ately north of lake Superior does not appear to be a continua-
tion of the original Leaf Hills moraine, although probably
contemporaneous with it, the name Highland moraine will
be used in order to prevent confusion until its western and
southern connections have been determined. The correlation
by Mr. Upham of the other moraines is satisfactory so far as
the writer is able to determine.
Highland Moraine. This moraine is named from High-
land station on the Duluth and Iron Range railroad, ten
miles northwest of Two Harbors on lake Superior, and 1 107
feet above the lake. The railway station, located in a deep re-
cession in the south side of the moraine, is surrounded on all
sides by high drift hills. The railroad crosses the summit
, of the moraine a mile north of the station at an altitude of
The Keweeftawan in Minnesota, — Elftman, 93
1744 feet above the sea and 1142 feet above lake Superior.
This is the highest point reached on the railroad. The High-
land moraine has its most prominent development in the vicin-
ity of this station and can be most easily. studied along a dis-
tance of fifteen miles by trails which start from Highland
statioil.
The moraine is seen in several places along the Cloquet
river and from Highland it extends continuously in a north-
easterly direction toT, 59 N., R. 8 W., where it unites with the
Itasca moraine. With an average width of two miles it runs
nearly parallel with the shore of lake Superior at a distance
of ten to fifteen miles north of it. Its maximum width is
five miles.
Itasca Moraine. On the Duluth and Iron Range rail-
road this moraine occurs as a low belt of hilly drift from three
to five miles northwest of the Saint Louis river. From the
railroad the moraine continues in a northeasterly direction to
the north of the source of the Saint Louis river in T. 59N.,R.
II W. Its course then becomes somewhat variable but lies
in a general easterly direction following approximately the
town line between townships 59 and 60 north to its junction
with the Highland moraine in T. 59 N., R. 8 W.
East of the union of these moraines a single prominent
moraine continues in a northeasterly direction to the Pigeon
river, diminishing in size toward the east until it disappears
in the province of Ontario. This belt is well defined around
lake Harriet ,* T. 60 N., R6 W.; around the lakes at the head
of the Poplar river in T. 61 N., R. 3 W.; from the Cascade
river in the southeastern part of T. 62 N., R. 2 W., to Devil
Track lake, which lies in the midst of the moraine; in the
southern part of T. 62 N., R. i E., and crossing the Pigeon
river in sections 20 and 21, T. 64 N., R. 4 E. The mo-
raine is characterized by a range of prominent hills 50 to 200
feet high extending its entire length.
Mesabi Moraine. West of range 11 west Mr. Upham
describes this moraine as follows: "Along the Mesabi range
east to the Embarras lakes northeast of Biwabik this moraine
is merged with the Itasca moraine. At Mesaba station, on the
*H. V. Winchell, 17th Ann. Report, Minn. Geol. and Nat. Hist.
Survey, p. 102,
94 The American Geologist, February, m\s
Duluth and Iron Range railroad, and within a mile south-
eastward, this Mesabi moraine comprises many hillocks and
short ridges twenty to forty or fifty feet high. Thence con-
tinuing northeast, it is represented by characteristic knolly
and hilly drift deposits and abundant bowlders on the south
side of the western part of Birch lake in T. 6i N., R. i5 W."*
Turning southward in the next five miles the moraine con-
tinues in a slightly north of east direction into the southern
part of T. 6i N., R. 7 W., lying from two to five miles north of
the Itasca moraine. For the next fifteen miles east of T. 61 N.,
R. 7 W., this moraine has never been definitely located. East-
ward the moraine occurs in scattering morainic areas. These
consist of the bowlder ridges and morainic deposits in the
central part of T. 63 N., R. 4 W., and in the region north of
Brule lake, between this lake and Poplar lake. South and
east of Hungry Jack lake T. 64 N., R. i W., along the Grand
Marais and Rove lake road is a belt of moraine deposit sev-
eral miles wide. This belt extends northward across the
east end of Hungry Jack lake and across the international
boundary near the west end of Rove lake. In Ontario this
belt is represented by a prominent moraine west and north
of the township of Marks.
Vermilion Morai?ie. This moraine, which was first de-
scribed by Mr. Upham in 1893 ,t passes from the south shore
of lake Vermilion northward to the region north of White
Iron lake. Beyond this region the drift deposits are not thor-
oughly explored arid on account of their scarcity it is diffi-
cult to map the course of this moraine. To the writer it
seems that the drift deposits observed at the following locali-
ties determine its position: In the northeastern part of T.
63 N., R. 10 W,;. the cast central part of T.O3 N., R.8 W.; Sec.
12, T. 64N., R, 7 W.; Sec. 11, T. 64 N., R. 6 W.: several miles
northwest of Little Saganaga lake; in the southern part of
T. 65 N., R. 4W.; on the international boundary several miles
north of Gunflint lake; and northwest of the township of
Marks.
The moraines whose courses are thus outlined and indi-
cated on the accompanying map represent belts of drift quite
*22nd Ann. Rep. Minn. Geol. Sur., p. 50.
t22nd Ann. Rep. Minn. Geol. Sur., p. 51.
The Keweenawan in Mitifiesota. — Elftman, 95
distinct in character from that in other parts of this region.
Each moraine as seen from a distance forms a range of irregu-
lar hills from fifty to two hundred feet above the surface in
its immediate vicinity.
The Highland moraine, when viewed from the south, ap-
pears more abrupt, with a greater difference in elevation be-
tween it and the land southward than is seen from the north.
With the other moraines the abruptness is seen on the north
side. The moraine formed by the union of the Highland and
Itasca moraine is abrupt on both sides.
Upon a closer examination it is found that in approaching
the Highland moraine from the south, the land in general is
devoid of any marked difference in elevation or roughness
beyond that due to the position of the bedrock. The moraine
is sharply defined and generally rises suddenly in hills one
hundred and fifty feet high. The belt of irregular hills, in
which occur numerous kettle holes over fifty feet deep, varies
in width from one-half mile to five miles. Toward the north
the hills are less prominent, rarely more than fifty feet higher
than the land immediately beyond the moraine whose north-
ern limit is thus not well defined.
The Itasca moraine west of range 12 west is not extensive
but it increases in extent toward the east, forming a belt of
hills from two to five miles wide, rising from twenty to seven-
ty-five feet above the land to the south and twenty-five to two
hundred feet above the land north of it. The northern
boimdary of the moraine is well defined while the southern
boundary merges into the non-morainic drift.
East of T. 59 N.,R. 8W.,the united Itasca and Highland
moraines, hereafter designated the Itasca — Highland moraine,
have their northern and southern boundaries sharply dis-"
tinguished. This belt averages three miles wide in its entire
extent and forms the highest land within the first fifteen to
thirty miles north of lake Superior.
The Mesabi moraine is not extensive in its western con-
fines. It reaches its maximum development in T. 60 N., R.
8, 9 and 10 W., and T. 61 N., R, 8 W, In these localities it
varies from one-half a mile to four miles in width. Eastward
the moraine is quite limited in extent until it reaches Hungry
Jack lake where its hills are very conspicuous. Like the
g6 The American Geologist, Febmary, i8i*s
Itasca moraine, the Mesabi moraine on its southern side
merges into the flat drift. Its northern limit is well defined by
irregular hills rising abruptly over two hundred feet above
the average surface of the country. The northern edge of this
moraine marks the dividing line in northeastern Minnesota
between the heavily covered drift area to the south and that
part where the drift is very scarce.
The Vermilion moraine which lies in the latter area was
estimated by Mr. Upham* to have an average thickness of
twenty-two feet in its greatest development. Northwest of
the township of Marks this moraine is over a mile wide and
200 feet deep and possesses the same structure described in
the other moraines.
Between the moraines the drift presents an even surface,
occurring usually in low, rolHng ridges, increasing in eleva-
tion as they approach the front of the moraines. These depos-
its consist partly of till and partly of modified drift.
THE NON-MORAINIC TILL.
Under this term is included the unstratified glacial drift
which is found in the greater part of northeastern Minnesota
and usually of no considerable thickness. On account of the
heavily wooded condition of the region it is difficult in many
cases to distinguish it from the modified drift. South of the
Highland moraine the till is not more than twenty feet thick
and qsually only a few feet. In the greater part of this area
it is covered by the lacustrine deposits of lake Duluth. In
the triangle between the Highland and Itasca moraines the
till appears in low rolling ridges with a general slope toward
the west forming the valleys of the Saint Louis river and its
eastern tributaries. A large part of this area is covered with
the usual swamps and muskegs, so that over areas several
townships in extent the surface varies only a few feet in alti-
tude. The till in this area consists of alternating layers of
material derived from the east and the northeast. This was
described and illustrated by Upham.+ It is also evident that
in the region immediately north of the Highland moraine the
upper till layer is of eastern origin, and that in the region im-
*Op. cit. p. 52.
tOp. cit. pp. 43 and 44, and Plate II.
The Keweenawan in Minnesota, — Elftman. 97
mediately south of the Itasca moraine the upper till layer is
of northeastern origin. Between the Itasca and Mesabi mo-
raines the till is largely covered by modified deposits and
is usually not more than twenty feet thick. In T. 60 N., R.
9W., however, it attains a thickness of more than fifty feet.
North of the Mesabi moraine the till is scarce and when pres-
ent is represented chiefly by boulders.
MODIFIED DRIFT.
The modified drift consists of the stratified gravel, sand and
clay deposited by streams flowing from the retreating ice.
Kames, eskers, plateaus, river deltas and valley drift repre-
sent it.
Kames are of common occurrence and are associated with
all the moraines. They are especially well developed along
the Highland and Itasca moraines and their eastern extension,
the Itasca-Highland moraines. In the Mesabi moraine, be-
tween Hungry Jack lake and the international boundary, are
also well formed kames, one of which is traversed for one-
eighth of a mile by the portage from Rose to Rove lake. Both
of the moraines northwest of Marks township in Ontario
show a strong development of kames and kettle holes.
Eskers were observed only in a few places. The most
prominent one is in T. 62 N., R. i VV., one to two miles west
of Devil Track lake. This is a narrow ridge over a mile long
and fifty feet high, above the land on either side. It is com-
posed of fine gravel and sand, with a few large boulders. In
this vicinity are also numerous kames, which occur near the
northern edge of the Itasca-Highland moraine.
Plateaus of sand and gravel similar to the kames in struc-
ture form isolated hills rising as high as 150 feet above the
surrounding area. The most conspicuous plateaus occur
immediately south of White Iron lake in T. 62N., R. 12 W.;
at the northeast end of Gabbro lake, T. 62 N., R. 10 W.: anS
at a number of localities several miles north of the Mesabi
moraine: These plateaus are especially noticeable since they
lie at some distance from the moraine.
River deltas occur most abundantly south of the Highland
moraine. They were formed in connection with lake Duluth.
The most prominent ones observed by the writer occur from
qS The American Geologist February, i898
450 to 600 feet above the present lake Superior on the follow-
ing rivers: Knife, Encampment, Gooseberry, Beaver, Bap-
tism and Temperance rivers. Smaller deltas are found at still
lower levels on these rivers as well as the Poplar, Cascade,
Devil Track and Brule rivers. In general it may be said that
the first mentioned streams present favorable conditions for
the formation of deltas at high levels and all streams at lower
levels. The greater extent of the deltas at. higher levels is
due to the greater volume of water discharged through these
rivers. In the area north of the Highland moraine the deltas
are not as numerous nor as extensive. South of the Mesabi
moraine in T. 60 N., R. 10 and 11 W., are several small deltas.
Valley drift consists chiefly of fine sand deposited in undu-
lating and nearly level tracts between the moraines. These
deposits are well shown in gravel pits and railroad cuts along
the Duluth and Iron Range railroad. The best exposure is
found at Cloquet River station, where an embankment twenty
feet high and a fourth of a mile long shows numerous beds of
stratified sand and gravel with very prominent cross bedding.
The original deposit formed a nearly level plain about one-
fourth of a square mile in area. In T. 60 N., R. 7 to 11 W.,
between the Itasca and Mesabi moraine the valley drift is ex-
tensively developed. So far as noticed these sand deposits
usually occur above the till. In the region between the
Itasca and the Highland moraines, where several overlapping
till sheets exist, modified deposits are found under later till.
This w^as noted by Spurr in T. 51 N., R. 17 W.*
WIND DEPOSITS.
West of the small lake in the N. W. \ of section 8, T. 60 N.,
R. 9W., and in the east central part of T. 60 N., R. 10 W.,are
deposits of unstratified sand above the till and modified drift.
These deposits present an uneven surface similar to that of
the moraines. The material is composed entirely of fine sand.
These dune like hills are referred to wind deposits which
are derived from the extensive deposits of modified drift in
the immediate vicinity.
*22nd Ann. Report Geol. and Nat. Hist. Survey of Minn., p. 123.
The Keweenawufi in Minnesota. — Elftman. 99
DISTRIBUTION OF BOULDERS.
Boulders are very abundant in the drift of this region.
Locally nine-tenths of the drift is made up of boulders from
four inches to ten or fifteen feet in diameter. The boulders
found in this region may be referred to two sources: ist, the
east; and, 2nd, the north and northeast. Those derived from
the former source are composed entirely of rocks found near
lake Superior, and consist of felsytes, quartz-porphyries,
amygdaloidal diabases, Beaver Bay diabase, anorthosyte, and
sandstones; those froiji the latter source consist of granites,
schists, jasper, hematite, magnetite, slates and gabbros, rocks
known to occur in place north of the present position of the
boulders.
The areal limits of the boulders from these two sources are
easily recognizable. The Highland moraiiie is composed en-
tirely of material derived from the east. The Itasca moraine
consists of northern drift. The Itasca-Highland moraine is
composed of material derived both from the east and the
north. The derivation of the drift included in this moraine,
from two sources; was previously mentioned on the Poplar
river* and around lake Harriet in T. 60 N., R. 6 W.f The
Mesabi and Vermilion moraines are derived entirely from the
north and northeast. In the triangle between the Highland
and Itasca moraines the glacial drift is composed of alternat-
ing layers of northern and eastern drift.
While the northern limit of the southern and eastern drift
is largely determined by the Itasca moraine, still the eastern
drift has been observed at Biwabik and Birch lake on the
Mesabi range; at lake Isabelle T. 62 N., R. 8 W. and on the
Temperance river in T. 62 N., R. 4 W. The material at the
last named places is scarce, and the fragments small in size,
the largest being about two inches in diameter. As this drift
occurs at a lower altitude and lies in the valleys of rivers
whose sources are in the area covered by the eastern drift,
some of it owes its present location to river transportation.
*N. H. Winchell. Tenth Ann. Report Geol. and Nat. Hist. Sur. of
Minn., 1881, p. 105.
tH. V. Winchell. Seventeenth Ann. Report Geol. and Nat. Hist.
Sur. of Minn., 1888, p. loi.
• •_
• •• •■
- • • — . •-
«
100 The Affterican Geologist, February, i898
The eastern drift has also been observed at considerable dis-
tances west of the area described in this paper.*
The greatest distance over which the boulders in this area
have been transported extends one hundred and fifty miles.
Numerous boulders of anorthosyte are found in the Highland
moraine and to some distance north of it. They are also
found in the St. Louis river valley, seventy-five miles west of
Encampment island in lake Superior. The anorthosyte
boulders just mentioned are to be referred to a strip not over
six miles wide and forty-five miles long between Encamp-
ment island and Carlton peak on the north shore of lake Su-
perior, the distinctive lithologic characters of which will be
mentioned later.
The drift of the northern ice-lobe does not appear to have
been transported a great distance. The greater number of
boulders are trom rocks whose ledges are not over fifty miles
distant, and for the most part indeed are within twenty or
thirty miles. It is also a conspicuous feature of this drift
that in places the moraines are represented entirely by boulder
ridges.
GLACIAL STRI^.
The direction and locality of the glacial striae in north-
eastern Minnesota recorded up to 1893 have been tabulated
by Mr. Upham.f Several important new observations are
as follows:
On the rock which forms the outer part of Grand Marais
harbor are numerous parallel glacial striae and grooves from a
few feet to fifty feet in length. There are two sets of these
striae which cross each other at a small angle. The more
prominent and numerous striations run about west, the other
set bears south of west. In a number of places west of Grand
]\Iarais are found striae which run west, or a little south of
west. South of the Pigeon river all striations run westerly.
The directions of the striae in the region included in the
accompanying map and indicated by arrows, may be briefly
summarized as follows: South of the Highland and Itasca-
♦Geology of Minnesota, Final Report, vol. II, 1888. Various county
reports.
Upham. 22nd Ann. Rpt., 1893, p. 44.
Spurr. 22nd Ann. Kept., 1893, p. 123.
top. cit, pp. 35-40.
. • *
The Keweenawan in Minnesota, — Elfttnan, loi
Highland moraine the direction is about west, varying locally
to 20° north of west; at Duluth the direction of the striae
varies, having a general southwest direction intersected by
striae running in all directions.*
The glacial markings observed within ten to twenty miles
north of the Itasca moraine run south to south twenty degrees
west. The one exception at Allen Junction where the stria-
tions run south, forty degrees west, is attributable to the in-
fluence of the Giant's range five miles north of this locality.
Northwestward of the above named limits the general direc-
tion becomes more westerly, becoming on Hunter's island
S. 20« W., Rainy lake S. 40^ W., and lake of the Woods S. 45 '^^
W. In many localities are numerous intersecting striations
made during the last stages of the ice retreat.
GLACIAL LAKES AND RIVERS.
The water derived from the receding ice when hemmed in
between the ice sheet on the one side and permanent land
barriers on the others, formed lakes whose positions are
marked at the present day by stratified clay, beaches and river
deltas. The glacial lakes of the lake Superior region have
been described with more or less detail during recent years.*
The highest shore lines of the glacial lakes are approximately
located upon the map.
Lake Saint Louis.\ As the ice receded toward the east into
the lake Superior basin the first lake formed was lake Saint
Louis, southwest of Duluth. The outlet of this lake was
toward the southwest from the central part of T. 47 N., R, 18
W., through a well defined river valley, at present seen along
the Saint Paul and Duluth railroad between Barnum and Carl-
ton. The highest point in this valley has an altitude of 1,125
feet above the sea. The ice barrier stood in the northwest
part of T. 48 N., R. 16 W. Although the lake did not extend
♦Lawson 20th Ann. Rep. Geol. and Nat. Hist. Sur. of Minn., 1891,
pp. 181-289,
Upham, 22d, ditto. i«g3, pp. 54-64.
Taylor, Amer.Gkol. Vol. XIII, 1894, pp. 380-383; Vol. XV, 1895,
pp. 1 19- 120 and pp. 304-314,
fAs recently described by Prof. N. H. Winchell in a paper as yet
unpublished, read before the Minn. Acad, of Nat. Sciences Feb. 1897;
also described in his unpublished report on Carlton county.
I02 Tlie American Geologist, February, i89>i
•
over forty square miles in area, it received a large volume of
water from the Saint Louis river.
Lake Nemadji. When the ice had receded beyond the
land barrier which formed the southeastern shore of lake
Saint Louis, a lower outlet with an altitude of 1,070 feet above
sea level, was uncovered in the northeast corner of T. 46 N., R.
18 .W. This outlet crosses the northern part of the township
and joins the outlet from lake Saint Louis in the northeast
part of T. 46 N., R. 19 W. Beyond the last named locality the
abandoned river channel continues to the southwest until it
forms the valley of the Kettle river, which flows southward
into the Saint Croix river. The stage of the glacial lake de-
termined by the outlet just described is called lake Nemadji
by Prof. Winchell, from the river Nemadji, which at present
drains a large part of the region formerly occupied by this
lake. Lake Nemadji continued to exist until a lower outlet
by way of the Bois Brule and Saint Croix rivers, thirty-five
miles east of the western end was uncovered.
Lake Duluth. The present altitude of the Saint Croix
outlet, according to Upham, is 1,070 feet above the sea level.*
This is the same as the present altitude of the outlet of lake
Nemadji. Allowing an uplift of former lake levels toward
the northeast, the Saint Croix outlet when first uncovered
was about ten feet lower than that of lake Nemadji.
Upham named the lake which had its outlet through the
Saint Croix river, "Western Superior Glacial Lake."f Tay-
lor used the name lake Duluth, without definition, upon a
map recently issued. !{! The name lake Duluth is used in the
present paper as a more appropriate and less cumbersome .
name for the lake whose outlet was by way of the Saint Croix
river, and which was formed by an ice barrier extending dur-
ing the maximum extent of the lake from the region a few
miles east of Port Arthur to the next lower outlet near the.
eastern end of the lake Superior basin.
On account of the rapid rise of the surface of the land
north of lake Superior the areal extent of this lake was not
♦Upham, Geol. of Minn. Final Report, Vol. II, pp. 642, 643. Mr.
Upham has supposed that the original level was 80 feet higher, and that
by erosion it acquired its permanent stage.
t22nd Ann. Report, Minn. Geol. & Nat. Hist. Surxey, p. 54.
^''Studies in Indiana Geography" 1897, Chapter X, p. 10.
The Keweenawan in Minnesota. — Elftman. 103
much larger than that of the present lake. Lake Duluth oc-
cupied the greater part of region occupied by lake Nemadji.
The prominent features of the lake are its clay deposits,
beaches and deltas.
Clay Deposits, These deposits are abundant in the entire
area of lake Duluth. In the region southwest of Duluth the
clay does not occur at an altitude over 1,050 feet above the
sea. Along the north shore of lake Superior the highest alti-
tude of the clay rises toward the northeast. This has been
verified by numerous aneroid measurements. North of Silver
mountain, Ontario, the clay is found at an altitude of 1,200
feet above sea level.
The clay is stratified and varies in thickness from a few
inches to one hundred feet, forming locally, flat areas of con-
siderable extent. The most abundant deposits are found in
the vicinity of the mouths of the larger glacial rivers. The
clay is composed entirely of very fine grained particles. In
the admirable sections through the clay along the Port Ar-
thur, Duluth and Western railroad, from Port Arthur to Sil-
ver mountain, and in the region southwest of Duluth, it is
seen that the clay originally had a blue or gray color. The
weathered surfaces always show a yellow to red color, and a
gradation from the blue to the red is noticeable in many recent
exposures. The depth of alteration varies considerably, ex-
tending from five to twenty-five feet below the surface. Many
streams have cut gorges through the deposit and have ex-
posed the pre-lacustrine surface of glacial drift and the earlier
rock formations.
Beaches, Above the clay, and often cutting into it, are
beaches which represent the stationary periods of the lake.
These beaches are found in numerous localities, but on ac-
count of the heavy timber it is impossible to follow them con-
tinuously. The highest beach of lake Duluth is always found
above the clay, and generally represents the highest lacustrine
deposit.
In the western end of the lake the altitudes of the glacial
outlets and of the highest beaches, as they are at present re-
corded, do not agree, unless we suppose an ascent of the
beaches of three to four feet per mile toward the northeast.
This does not seem warranted by observations in other parts
104 Tite Afnerican Geologist. February, i898
of the region. It seems that a further investigation in the
field is necessary to determine whether the highest beach at
Duluth, 1,137 feet above sea level, is associated with the gla-
cial passes thus far described, and whether the Boulevard
beach at Duluth may not be regarded as the highest beach of
lake Duluth.
Along the Duluth and Iron Range railroad the highest
margin of the lake is found between five and six miles north
of Two Harbors, and at an altitude of about 1,100 feet above
sea level. The lake shore is not clearly defined on account
of the even slope of the glacial drift, but it does not appear to
extend over 500 feet above lake Superior. At mount Jose-
phine the highest beach has an altitude of i ,209 feet above sea
level. North of Silver mountain the Port Arthur, Duluth
and Western railroad crosses the highest beach, about thirty-
eight and one-half miles west of Port Arthur, at an altitude of
about 1,230 feet above sea level.
Deltas, Delta deposits are prominently developed on the
Knife, Encampment, Gooseberry, Beaver, Baptism and Tem-
perance rivers. The most extensive development of these
deltas was contemporaneous with the stages of lake Duluth.
Lake Omimi, Before the ice had receded beyond
mount Josephine it retained a lake of about 40 square miles in
area lying in the upper valley of the present Pigeon river.
The lake bed has an altitude of 1,255 to 1,360 feet above the
sea. Its lowest point is thus about 50 feet higher than the
upper stage of lake Duluth. The chief deposit consists of
stratified clay, exposed along the Pigeon river and its tribu-
taries. Beaches have as yet not been identified. The west-
ern shores of this lake were formed by high rock ridges. The
ice barrier during the largest extent of the lake stood in the
vicinity of the western end of the Grand Portage trail. The
outlet, which has not been definitely located, was most proba-
bly toward the southeast, and closely connected with the ice
barrier, which, upon receding, continually uncovered lower
ground. This lake in part occupied a portion of th*e area
previously occupied by the northern ice lobe. When the ice
receded from the vicinity of Grand Portage, lake Omimi dis-
appeared. The name Omimi is taken from the Chippewa
name for Pigeon river.
The Kewecfiawaii in Miimesota, —Elftfnan, 105
Lake Kaministiquta. This lake was described by Tay-
lor* after this paper was written. As the writer has since then
visited that region, his interpretation of the facts is added.
As it has been mentioned before the highest lacustrine de-
posits along the Port Arthur, Duluth and Western railroad
occur in the vicinity of Silver mountain and do not extend
above the altitude of 1,230 feet above sea level. The region
northwest of Silver mountain is very favorable to the deposi-
tion of lake beaches, etc., had it been submerged. On the
north side of the Giant's range, which crosses the central part
of Marks township from the southwest, lacustrine deposits
occur at an altitude of 1,500 feet and less, or about 300 feet
higher than those at Silver mountain. These higher deposits
correspond to those described by Taylor along the Canadian
Pacific railroad. It seems that the area of lake Kaministi-
quia is more restricted than that originally outlined. Lake
Kaministiquia is regarded by the writer as a lake occupying
the basin formed on the south by the Giant's range, on the
west and north by the "height of land," and on the east by the
ice sheet. The southwestern point of the ice barrier at the
time of greatest extent of the lake stood at the east end of
the Giant's range, near the Kaministiquia river. Upon the
recession of the ice beyond the high land, the lake immedi-
ately emptied into lake Duluth. It is noticeable that the lake
existed in a region occupied at an earlier date by the northern
ice lobe.
Lake Algonquin. The non-existence of lake Warren
in the lake Superior region has been quite fully discussed
by Taylorf and Upham. J The beaches below those of lake
Duluth are referred to the stages lake Algonquin. These
beaches are without strongly marked or uniform characters
which would serve to identify them without continuous trac-
ing. On this account little can be added to the previous
knowledge of this lake in the region northwest of lake Supe-
rior. East of Port Arthur the highest beach recorded by
♦Amer. Geol., Vol. XX, pp. 117.
tAMER. Geol., Vol. XVII, 1896, pp. 253-257; pp. 397-40o; Vol.
XVIII, 1896, pp. 108-120; ^'Studies in Indiana Geography/' Chap. X,
1897.
JAmer. Geol., Vol. XVII, 1896, pp. 238-240; pp. 400-402; Vol.
XVIII, 1896, pp. 169-177.
io6 The American Geologist February, mi6
Taylor and others seems to be the highest beach of lake Al-
gonquin.
Nipissing Great Lakes, The highest beach of this post-
glacial lake, called the Nipissing beach by Taylor, forms a
conspicuous feature near the level of lake Superior from
Beaver Bay to Port Arthur. The conclusions drawn by Tay-
lor with respect to this beach are satisfactory. The beach
is 6 1 feet above lake Superior at Port Arthur and is readily
recognized at lower levels, at Wauswaugoning Bay, Grand
Portage, Grand Marais, Cascade river, three miles east of the
Temperance river at Tofte postoffice, and one-half a mile west
of the Baptism river. West of the last-named locality the
beach has been obliterated by recent wave action, and proba-
bly passes below the level of lake Superior near Beaver Bay.
Taylor places its distance below the lake at Duluth at 25 feet.
This gives a rise of 86 feet toward the northeast, between Du-
luth and Port Arthur.
Lake Gabbro. North of the Mesabi moraine and east of
Gabbro lake, a glacial lake having an area of one hundred
square miles at its maximum extent, existed for some time
after the recession of the ice from the moraine. The shores
of the lake were formed by the Mesabi moraine on the south,
a high rock ridge on the west, the ice barrier on the .north
and the highlands on the southeast. This region forms a
basin, sloping toward the northwest, which is covered more
or less with stratified sand and fine clay. Beaches have not
been identified. The short duration of the lake and the
character of the region in which it existed did not present
favorable conditions for the formation of prominent beaches.
The outlet was south to the Stony river. The lake was named
lake Gabbro on account of its central location in the gabbro
area of northeastern Minnesota.
Glacial Rivers, The courses of the glacial water are
quite conspicuous in many places. The valleys of the Clo-
quet. Saint Louis and Embarras rivers show that these rivers
at one time were much larger. The extensive stratified de-
posits in these valleys indicate a drainage from the northeast.
At the headwaters of these rivers abandoned channels across
the present water divide show that their sources were further
north and east. The channel across the central part of T. 59
The Keweefiawan hi Min?tesota, — Elfttnan. 107
N., R. II W., connects the Saint Louis with the Stony river.
The southern head of the Stony and that of the Cloquet river
are on the same level. The sources of the Baptism and Isa-
bella rivers are upon the same level in a valley which cuts
through the Itasca-Highland moraine. The stratified de-
posits in this valley south of the moraine are composed partly
of material brought from the region north of the moraine,
indicating a drainage toward the south. These are the chief
glacial rivers, others of minor importance show the same
phenomena as those just mentioned.
GLACIAL EROSION.
Glacial erosion in the greater part of this region did not
extend much beyond the removal of the decomposed surface
rock. It was most active along the main direction of the ice
lobes. ' The change in the topography is not very marked.
The tendency to change the V-shaped valleys of the pre-
glacial erosion to U-shaped valleys is well exhibited along the
north shore of lake Superior where the low dipping strata are
cut off near the side of the valley. The Sawteeth mountains,
which are chiefly due to pre-glacial faulting, were not changed
to any extent beyond the rounding oil of the edges and sides
facing the direction from which the ice came. The greater
part of the rock which makes up these hills is a medium
grained compact diabase, which resists weathering better than
the amygdaloidal rocks above it, which have been largely re-
moved by glacial action.
The rocks forming the present surface are generally quite
fresh. Yet in some areas the basal gabbro is entirely decom-
posed and does not appear to have been subjected to exten-
sive erosion. The existence of these areas may be due to
deep local pre-glacial weathering. When the region was
levelled off by glaciation the lower portion of the altered rock
remained in place.
SUMMARY.
The evidence presented by the structure and composition
of the glacial drift, the striae, and other glacial phenomena,
show that the drift deposits were formed by two lobes, one of
which moved in a general southwesterly direction through
io8 The American Geologist, February, laft*
the lake Superior basin, and the other with its central axis
across the Rainy lake region, moved S 40° W.
The Superior lobe overflowed its basin and spread west-
ward and northward to the Giant's range. The ice then re-
ceded from the north at least as far as Highland, but again
advanced northward as far as Giant's range. Receding again
.to Highland another advance was made, extending north-
ward from five to ten miles. After the recession from the last
advance, the Highland moraine was formed along the rim
of the basin. Further east, in conjunction with the Rainy
lobe, it formed the Itasca-Highland moraine. During the
farther recession of this lobe' the glacial lakes Nemadji, Du-
luth, Omimi and Kaministiquia were successively formed and
drained.
The history of the Rainy lobe is more complex than that
of the Superior lobe. While the latter filled its basin, the
former filled its basin, the southern barrier of which was the
Giant's range. The till between the Highland and Itasca
moraine shows that each ice lobe alternately advanced beyond
its basin and retreated. At least two such excursions by each
lobe are recorded in cuts along the Duluth and Iron Range
railroad. The Rainy lobe, during the recession, subsequent
to the return from its last southern trip formed the Itasca,
Itasca-Highland, Mesabi and Vermilion moraines. The two
lobes were contemporary, forming the Highland, Itasca and
Itasca-IIighland moraines at the same time. While these
moraines were being formed the glacial water was carried off
by the Saint Louis and Cloquet rivers. The Superior lobe
then receded toward the northeast and its northern border re-
mained in close proximity to the Itasca-Highland moraine.
The Rainy lobe receded northward from the Itasca and
Itasca-Highland moraines. Since lake Omimi covered in
part the region occupied by this lobe, the Superior lobe had
not receded beyond mount Josephine at the time the Mesabi
moraine was being formed. The drainage of the Rainy lobe
was to the southward, chiefly through the Saint Louis, Clo-
cjuet, Isabelle-Baptism, Temperance and Pigeon rivers. The
large volume of water discharged into lake Duluth carried
with it an abundance of drift. The coarser material was de-
posited at the mouths of the rivers, forming deltas, and finer
The Keweenawan in Mtfincsota, — Elftmaju 109
material, was carried into the lake forming the extensive clay
deposits. When these waters found an outlet toward the
north, the volume emptying into lake Duluth was greatly re-
duced and the transportation of debris correspondingly dimin-
ished.
The scarcity of the drift north of the Mesabi moraine
shows that the ice did not linger long in that region. From
the position of the moraines it seems that the recession in the
western part of the region was even more rapid than' that in its
eastern portion. This would indicate that the general reces-
sion of the Rainy lobe was toward the northeast. The drain-
age, while the Vermilion moraine was being formed, was
chiefly from the northeast through valleys at present occupied
by the streams emptying into Birch lake, and from thence
westward through the Embarras river to the Saint Louis
river. After its brief rest at the Vermilion moraine the ice
receded to the northeast into Canada. Since lake Kaministi-
quia occupied in part the region covered by the Rainy lobe
after this lobe had receded beyond the Vermilion moraine,
the Superior lobe had not, at that time, receded beyond Port
Arthur.
It may be mentioned in passing that this interpretation of
the moraines may necessitate a revision of the interpretation
of the glacial phenomena in central Minnesota. So far as the
writer can judge from his observations and the descriptions*
of the glacial drift in this part of the state it seems that there
is evidence of the meeting of ice lobes from different direc-
tions; i. e., the Superior lobe from the northeast and another
lobe from the northwest. The relation of these lobes seems
to be analogous to that just described between the Superior
and Rainy lobes. It may be suggested here that the Kettle
moraine of the Wisconsin geologists, which is recognized
over an extensive territory, and whose relative chronological
position has been determined, continues into Minnesota, and
perhaps is represented by the Highland, Itasca and Leaf Hills
moraines.
*Final Report, Vol.' II, Minn. Geol. & Nat. Hist Survey, 1888,
County Reports.
no The American Geologisf. February, isas
AN ACCOUNT OF THE RESEARCHES RELATING
TO THE GREAT LAKES*.
By J. W. Spenceb, Toronto.
An old text book upon geology briefly says that the lake
basins are due to movements of the earth's crust. What the
movements were and how they affected the history of the
great lakes was left a subject of discovery for recent years.
In the mean while, theories arose as to their origin, the dis-
posal or modification of which was fraught with difficulties
as great as those of discovering the history itself. Ramsay
had attributed the origin of the American lakes to glacial ex-
cavation ;f Hunt, Newberry, Carll and many others had col-
lected the evidence of buried channels occurring in the lake
region. Gen. G: K. Warren J had followed up the observa-
tions of Prof. H. Y. Hind § in the history of the Winnipeg
basin, and proposed the northeast warping as closing the
Ontario basin, to such a degree that he may be considered
the father of lacustrine geology. l>ut the great impetus
towards the investigation of the great lakes is due to Prof. J.
S. Newberry, whose contribution was followed by one from
Prof. E. W. Claypole.1! To give a full account of the re-
searches concerning the great lakes, and to tell how each
author had contributed to the subject would make a very long
chapter. As the present writer has been so closely connected
with the pioneering study of the subject, and has announced
progress from time to time before the American Association
it seems a fitting opportunity to tell how his investigations
have been influenced by his co-workers, leaving to others the
narration of the most recent studies.
Newberry followed upon the lines of Ramsay in attributing
the basins of the lakes to glacial excavations, yet there was a
counter current in his writings which finally advocated that
the glacial excavation had taken place only after their courses
*Read at the Detroit meeting of the A. A. A. S., 1897.
tQuart. Jour. Gcol. Soc, Lond., vol. XVIII, pp. 185-204, 1862.
t Appendix J., Rep. of the Chief of Engineers, U. S. A., 1875; Am.
Jour. Sci. (3), vol. XVI, 1878. pp. 416-431.
§Report on the Assiniboine and Saskatchewan Exploring Expedi-
tion. By Henry Youle Hind. Toronto, 1859, pp. 1-20.
; 'Geology of Ohio. vol. II, 1874, pp. 72-80.
^On the pre- Glacial Geography of the region of the Great Lakes,
E. W. Claypole. Can. Nat., vol. VIII, 1877, pp. 187-206.
Researches relating to the Great Lakes. — Speticer, i \ \
had been pre-d.etermined by river action. Adopting the
teachings of Agassiz and Newberry, and going much farther,
an influential school was developed which attributed the su-
perficial features of the northern regions almost entirely to
the action of continental ice, — in spite of the teachings of Les-
ley, Dawson, Whitney and others. The extreme view^s, as
represented by Dr. G. J. Hinde,* made the ice plough dig
out the St. David's, Dundas, and other valleys, irrespective of
their direction, as compare^ with that of the ice flow. Such
speculations were most common at the close of the eighth de-
cade of the century, when the writer commenced his studies
upon lacustrine history — concerning which his first paper was
on the "Discovery of the Outlet of the Basin of Lake Erie,
ctc.,f (1881). The appearance of this "avant courier," was
due to the enthusiastic reception given by Prof. J. P. Lesley
to the writer's discovery of the reduction of rocky barriers
beneath the superficial drift, between lake Erie and the Dun-
<las valley, at the head of lake Ontario, indicating an outlet
for the Erie basin by a channel, the lower end of which is
deeply buried by drift deposits. Prof. Lesley pointed out
that this discovery satisfied the necessity for some such outlet
to the Erie basin, as Hunt and Newberry had found buried
channels beneath the lake, and Mr. J. F. Carll had discovered
that the drainage of the Upper Allegheny, and other streams,
had been reversed, having flowed northward into the Erie
basin in pre-glacial days.
The writer's paper referred to not only described the out-
let of the Erie basin, but also showed that the Niagara river
was not needed in ancient times. Shortly afterwards this
idea was confirmed by Dr. Julius Pohlman J who found that
the Niagara channel was not sufficiently deep for the drainage
of the buried valleys in the vicinity of Buffalo.
In the same paper, the valley-like features beneath the
lake waters were analvsed and established. But at that time
*Glacial and Interglacial strata of Scarboro Heights, etc. Canadian
Journal, April, 1877, p. 24,
t Discovery of the Preglacial Outlet of the Basin of Lake Erie into
that of Lake Ontario; with notes on the Origin of our Lower Great
Lakes. By J. \V. Spencer; Proc. Amer. Phil. Soc, XIX, 198, 2n.,
March 30, 1881, pp. 300-337-
JThe Life-history of Niagara. By Julius Pohlman. Trans. Am.
Jnst. Min. Eng.
1 1 2 The American Geologist, Febmary, i8»>
•
the course of the ancient drainage could not be traced be-
yond the meridian of Oswego. The writer also objected to
the theory of the glacial excavation of the basins on account
of the stream-like sculpturing of the land, and the sub-lacus-
trine escarpments; and on account of the glaciation of the re-
gion being everywhere at sharp angles to the escarpments,
whether above or below the surface of the lakes. These views
and the discovery of the outlet for the ancient Erie basin con-
firmed the teachings of Prof. J. P. Lesley, who, from being a
progenitor of the science of topography became the father of
geomorphy, of which the lake history is one of the phases.
In speaking of the origin of the lake valleys. Prof. Lesley*
says: **For a number of years, I. have been urging upon
geologists, especially those addicted to the glacial hypothesis
of erosion, the strict analogy existing between the submerged
valleys of lakes Michigan, Huron and Erie, and the whole
series of dry Appalachian 'valleys of VHP, stretching from
the Hudson river to Alabama; also of Green bay, lake On-
tario and lake Champlain, with all the 'valleys of IL and HL'
One single law of topography governs the erosion of them all,
without exception, whether at present traversed by small
streams or great rivers, or occupied by sheets of water; the
only agency or method of erosion common to them all being
that of rainwater; not in the form of a great river, because
many of them neither are nor ever have been great water-
ways."
Notwithstanding the short-comings, and what are now
known to be errors of detail, the paper on the pre-glacial out-
let of Erie attracted considerable attention as a new depart-
ure; and at the time Prof. James Geikie, who is well known
to be one of the leading glacial ists, expressed himself as fol-
lows, under date June 21, 1881: "I have always had misgiv-
ings as to glacial erosion of the great lakes, * * * and
now your most interesting paper comes to throw additional
doubt upon the theory in question. Possibly those who have
upheld that view will now give in. Your facts seem, to me at
least, very convincing. I never could understand how those
great lakes of yours could have been ground out by ice. The
* Report Q4 of the Geological Survey of Pennsylvania, 1881, pp.
399-406.
Researches relating to the Great Lakes. — Spe?icer. i [ 3
physical conditions of the ground seem to nie very unfavora-
ble." Prof. G. K. Gilbert, on June 15, 1881, vi^rote: "My
first geological field work was in the drift of the Erie basin,
and the problem of the origin of the basins of the great lakes
has always had great attraction for me. Had I been able to
understand its solution, my working hypothesis would have
been that which you have demonstrated so thoroughly. * *
* The matter has certainly never received a demonstration
until your paper appeared. * * *"
At tliis time the writer was struggling to find the outlet of
the basins, and looked in every possible direction for buried
channels without avail. While the St. Lawrence valley, be-
yond the outlet of lake Ontario, was evidently only a continu-
ation of the drowned valley occupied by the lake, and while
the lower St. Lawrence indicated an elevation of the conti-
nental region to more than 1,200 feet (when the cafion of
the Saguenay was being excavated), the evidence of the local
oscillation of the earth's crust was not yet forthcoming. The
deep canon of the Dundas valley, and the observations of Prof.
Gilbert that the Irondequoit bay was drowned to a depth of 70
feet was taken as evidence of terrestrial oscillation, but later
the writer found that the St. Lawrence, after leaving Ontario,
was in part flowing over a valley buried or drowned to a
depth of 240 feet; accordingly the Dundas and Irondequoit
valleys were no evidence of local oscillation, which had to be
found elsewhere.
In concluding a notice of this early work,* the modern
aspect of the Niagara river was emphasized, and the valley of
St. Davids was regarded as of inter-glacial origin — in defer-
ence to the prevailing theories of the time — in place of being,
as is now known, the channel of an insignificant stream of
greater antiquity. The Finger lakes of New York were ex-
plained as closed up valleys which had formerly drained the
rivers of the highlands of New York, as for example Seneca
lake, which has since been found to be the ancient course
of Chemung and its tributaries. About this time the writer,
from the data collected by the Geological Survey of Pennsyl-
*A short study of the Features of the Great Lakes, etc. J. W.
Spencer. Proc. A. A, A. S., vol. XXX, 1881, pp. 131-146; and Surface
Geology of the Region about the western end of lake Ontario. J. W.
Spencer, Can. Nat., vol. X, 1882, pp. 213-236, and 265-312.
114 The American Geologist, Febmary, i898
«
vania, pointed out the probability that the Monongahela and
upper Ohio had formerly been reversea and drained into the
Erie valley. * This hypothesis was afterward amplified by Dr.
P. Max Foshay,t disputed by Prof. I. C. White; modified and
confirmed by Mr. F. Leverett, J and finally, with some modi-
fications, reconfirmed by Prof. I. C. White.§ In order to
test the validity of his objections to the hypothesis of glacial
excavation, the writer visited Switzerland and Norway for
the purpose of personally observing the mechanical eflFects
of modern glaciers, with the result that he saw in them only
the agents of abrasion — the ice moulding itself round obstruc-
tions, or smoothing off irregularities, and not ploughing out
channels. |! Indeed, in a more recent visit to Norway, it be-
came apparent that the great glacial valleys still preserve
many base levels of erosion — the doctrine of which has not
been applied to them, and consequently their history is as
yet unwritten. The extreme views concerning glacial ero-
sion, held a decade ago, are now greatly modified and do not
belong to the present day.
In 1882, fragments of great beaches, and others which
were delta deposits, were described as occurring about the
western end of lake Ontario at various elevations from 500 feet
above the lake down to its present level. ^ Other fragmeuts
of beaches had been known for many decades, the most nota-
ble of which were the ridge roads of New York state, that
Prof. James Hall, as early as 1842, found to be rising gently
upon proceeding eastward ;** and the same was found to be
true at the eastern end of lake Ontario. About this time
Prof. Gilbert was studying the beaches of the western lakes,
and Mr. Warren Upham those of the Winnipeg basin. The
*On the ancient upper course of the Ohio river emptying into lake
Erie. Proc. Am. Phil. Soc, Phil., vol. XIX. 1881.
tPreglacial Drainage and recent Geological History of western
Pennsylvania. Am. Jour. Sci., vol. XL, 1890, pp. 397-403-
JPleistocene fluvial plains of western Pennsylvania. Am. Jour.
Sci., vol. XLII. i8gi, pp. 200-212; and Further studies of the Upper
Ohio basin. Am. Jour. Sci., vol. XLVII, 1894, pp. 247-283.
§ American Geologist, vol. XVIII, 1896, pp. 368-379.
II The erosive power of glaciers as seen in Norway. Geol. Mag..
Lond., Dec. iii, vol. IV, 1887, pp. 167-173.
1 Surface Geology about the region of the western end of lake On-
tario, cited before. \
J ** Geology of New York. Vol. IV, 1843, p. 35i-
Researches relating to the Great Lakes, — Spencer, 1 1 5
beaches in both places were found to record the evidences
of gentle terrestrial movements. Following up his investi-
gations, Prof. Gilbert connected the various fragments of a
great beach upon the southern and eastern sides of lake
Ontario, as far as Adams Centre, near Watertown, N. Y.,*
and found that the old waterline was deformed to the extent
of several hundred feet in proceeding northeastward. This
was. an admirable piece of work, which was invaluable to the
writer, who extended the observations farther -f and made use
of them in measuring the amount of the long sought for ter-
restrial deformation at the outlet of lake Ontario, and found
that these post-glacial movements were sufficient* to account
for the rocky barrier across the Laurentian valley, producing
the basin which retains the waters of lake Ontario. The
channels across this rocky barrier, however, were closed with
drift deposits reaching to a depth of 240 feet. In thus estab-
lishing the ancient drainage of the Ontario basin, after years
of obser\'ation, often representing but little progress, the
phenomena of the basin were discovered without the glacial
theory of. erosion. Then the writer found that the drowned
channels crpss lake Huron, and passing through Georgian
bay, continued beneath hundreds of feet of drift, eastward of
the Niagara escarpment, and joined the Ontario valley a few
miles east of Toronto. A similar channel (the Huronian)
crossed the sta.te of Michigan, passed through Saginaw bay,
and over the sub-lacustrine escarpment, to the deeper chan-
nel of the Huron basin. J The Erie (Erigan river) drainage
had been found to pass into the head of the Ontario basin.
Thus was discovered the course of the ancient Laurentian
river and its tributaries of antiquity. These upper basins were
also affected by the terrestrial tilting recorded in the beaches,
as well as by the drift obstructing them.
Prof. Gilbert, who had, many years before, mapped
beaches at the head of lake Erie§ afterwards measured the
* Report of the meeting of the Am. Assc. Adv. Sci., Science, Sept.,
1885, p. 222.
tXhe Iroquois Beach: a Chapter in the Geological History of Lake
Ontario, by J. W. Spencer. Trans. Roy. Soc. Can., 1889, pp. 12^-134.
(First read before Phil. Soc, Wash., March, 1888.)
t Origin of the Basins of the Great Lakes. Q. J. G. S. (Lon.), vol.
XLVI, 1890, pp. 523-533.
§'See Geology of Ohio, vol. II, 1874.
1 1 6 The American Geologist, Februnry, i898
deformation recorded in the deserted shore at the eastern
end of the lake;* while the writer surveyed the old water
margins across Michigan, and on the Canadian sides of lakes
Ontario, Erie and Huron, and in portions of New York.f
After this, very little work was done upon the deserted shores
for several years, when Mr. F. B. Taylor commenced his re-
searches about the northeast portion of Georgian bay, lake
Michigan, etc.;J and Dr. A. C. Lawson carried on similar ob-
servations north of lake Superior,§ and Prof. H. L. Fairchild
in New York. The deserted beaches show but little terres-
trial oscillation about the western end of lake Erie, but it in-
creases to\vards the northeast and amounts to four to seven
feet per mile.
With the surveys of the deserted beaches, new questions
arose concerning the history of the lakes and of Niagara river,
which forms an inseparable chapter. At the same time, op-
posing hypotheses presented themselves.
None of the beaches have been fully surveyed. They oc-
cur at various altitudes from near the greatest elevation of the
land down to the levels of the lakes, and they have not always
been separated from other Pleistocene deposits. While there
are questions as to the higher forms, those from lower levels
have undoubtedlv been accumulated about extensive bodies
of water — the character of which is the subject of disagree-
ment. The writer has regarded them as accumulations at
sea-level, and other observers as margins of glacial lakes,
irrespective of their elevation. The theoretical aspect is not
one likely to be settled speedily. Those who advocate the
glacial character of the lakes have sought to terminate the
beaches against morainic deposits to the northeast, but their
* The History of the Niagara River. 6th Rept. Com. State Res.
Niag.. Albany, 1890, pp. 61-84.
tThe Iroquois Beach, etc., cited before. Deformation of the Iro-
(|Uois Beach and Birth of Lake Ontario, Am. Jour. Sci.. vol. XL, 1890.
pp. 443-451; Deformation of the Algonquin Beach and Birth of Lake
Tluron. lb., vol. XLI, 1891, pp. 11-21; High Level Shores in the Re-
gion of the Great Lakes, and their Deformation. lb., vol. XLI, 1891,
pp. 201-21 1 : Deformation of Lundy Beach and Birth of Lake Erie, lb.,
vol. XLVIII, 1894, pp. 207-212.
t Numerous papers recently published in Am. Jour. Sci., American
(ieologist. and Bui. Geol. Soc. Am.
§Sketc]i of the Coastal Topography of the North Side of Lake Su-
perior. 20th Report of the Geol. Sur. Minnesota, for 1891, pp. 181-289.
Researches relating to the Great Lakes. — Speticer. 117
ice dams have been frequently thrown along lines beyond
which the beaches have subsequently been traced. Thus
Prof. Claypole* made ice dams in Ontario where open water,
bounded by beaches, was afterwards found to prevail. At
Adams Centre, Prof. Gilbert drew an ice dam for the Ontario
basin, beyond which, however, the writer found that the
old shore line extended, and this was later confirmed by Prof.
Gilbert. Mr. Leverett made an ice dam at Cleveland, beyond
which the writer has been informed by two observers that the
beach extends, and Prof. Gilbert and Mr. Leverett described
another glacial dam near Crittenden, N. Y., beyond which
the beaches have been discovered by Prof. Fairchild. An-
other diagnosis of the glacial lakes is the occurrence of gravel
floors over low divides, which are regarded as the outlets of
them, and upon this feature alone many such lakes have been
named. But the advocates of these glacial outlets have not
explained how the terraces (at hundreds of feet above the
drainage) upon the southern side of them are indistinguish-
able in character from those upon the northern side.j If
these supposed outlets be evidence per se of glacial dams
then the most perfect which the writer has ever seen may be
found within 16° of the equator, at an altitude of less than
800 feet, suggesting that the Mexican gulf had a glacial dam,
discharging into the Pacific ocean across the isthmus of Te-
huantepec — a suggestion which no one would seriously con-
sider. The writer has also presented the hydrostatic objec-
tionsj to the impossible long continuance of some of the sup-
posed dams, the location of which deniands their drainage
across ice itself, which would soon be penetrated by the
warmer waters so as to reduce their level. By straightening
out the deformation recorded in the deserted shore-lines,
some of the beaches are shown to have undoubtedly been
formed at sea-level. § While recent surveys report the dis-
<.overy of additional glacial lakes, or the splitting up of those
♦Report of the meeting Am. Assoc. Adv. Sci. Science, Sept., 1895,
p. 222.
t Channels over divides not evidence per se of glacial dams. J. 'W.
Spencer. Bvll. Geol. Soc. Am., vol. Ill, 1891. p. 491.
t Post- Pliocene continental subsidence versus ice-dams, by J. W.
Spencer. Bull. Geol. Soc. Am., vol. II, pp. 465-476, 1890.
§Tlie Iroquois Beach, etc., cited before; and, Deformation of the
Iroquois Beach, cited elsewhere.
Ii8 The American Geologist. Febmary, i«^^
first described under new names, the survey of the high level
terraces in the mountain regions has suggested to the writer
counterbalancing evidence of the occurrence of glacial dams,
but this is a study which has been postponed, partly on ac-
count of the prejudice against post-glacial subsidence and
partly on account of the writer's absorption in other ques-
tions of physical changes. Whatever may be the ultimate
fate of the theory of glacial dams, the opposing hypotheses
have given zest to the investigations to the degree of ad-
vancing our knowledge of the lake history. . .. ' .
In the survey> of. the beaches,, besides the terrestrial de-
V formation recorded, there. seems to be. no more important
. discovery than when the writer found how the. Huron, Micbi-
. gan. and Superior waters (the Algonquin gulf or lake) origin-
V ally emptied to the northeastward of the Huron basin in place
^ of discharging into lake Erie ; after which by the northeastern
' tilting of the land *'the waters were backed southward and
. overflowed into the Erie basin, thus making the Erie outlet of
the. upper lakes to be of recent date."* This conclusion was
V established by. the survey of the Algonquin beach which r^-
. corded the necessary tilting. The first survey was suspended
i\ear Balsam lake, where an overflow was found; and, accord-
ingly, in the original announcement, the geaeralizations were
* not carried iartJier, although there was a lower depression in
. the vicinity of lake Nipissing, which was shortly afterwards
made use of by Prof. Gilbertt and the writer. With the
further elevation of the land, the lower beaches — rpartly meas-
ured at that time ^1887-8), represented the .surface of the Al-
gonquin water discharging by the Nipissing route alone.t
This has since been worked out by Mr. Taylor.§
Co-existing with the Algonquin gulf: or. lake was the
, Lundy gulf or lake, occupying part of the Erie basin, and ex-
. tending into the Ontario, having substantially the same level.
: Hoth of these' bodies of water extended much farther towards
. the northeast than their successors, although nwre contracted
in the opposite directions — the effect of the more recent tilt-
• *Proc. A. A. A. S.. vol. XXXVII. 1888, p. 199-
. tThe History of the Nipissing River,
t Deformation of the Algonquin Beach, cite(J before.
• ' §T1ie Ancie-ilt Strait of Nipissing. F. B. Taylor. Bull. Geol. See.
Am., vol V, 1893.
ResearcJies relatifig to the Great Lakes, — Spencer, 1 19
ing of the land. Prior to the existence of these separate
bodies of water, higher shore-lines were formed, and the
great gulf or lake bounded by them was called the Warren
water, which name the writer has defined as applicable to the
great open water of the region, until after the formation of
the Forest beach — its most perfect episode — after which it
was dismembered into the Algonquin and Lundy waters,*
During the changing stages of Warren water, its configura-
tion was somewhat varied but not sufficiently to call the water
by a multiplicity of names, according to the changing levels.
The old shore lines form prominent features, requiring
nomenclature for the most important. And additional nam-
ing only adds confusion. Some of the beaches have been re-
named by Mr. Leverett, | contrary to the usage of naturalists.
With the continued elevation of the land, the Algonquin
water sunk to the level of the Nipissing beach (of Taylor) and
the Lundy became dismembered, and formed an insignificant
lake Erie. J In the Ontario basin, the water sunk to the Iro-
quois beach and lower levels, and Niagara falls had their
birth, after the river had first been a strait. Remnants of
beaches of that time were long ago observed, not only in the
vicinity of Niagara, but also at the head of the lake. With
the temporary pauses recorded, the waters of the upper level
were speedily lowered to that of the Iroquois beach, and then
the Niagara river descended only 200 feet, in place of 326 feet,
as at present. The effect of this diminished descent upon the
excavating power of the falls was first pointed out by the
writer in i888§and published in 1889. With the continued
lowering of the waters in Ontario basin, the descent of the
Niagara increased to 80 feet more than at present, as first
shown by Prof. Gilbert ; but later, by the tilting of the earth's
crust north of the Adirondack mountains, the outlet of the
Ontario basin was raised, causing the backing of the waters,
so as to reduce the descent of Niagara river to its present
amount.
* High-level shores in the region of the Great Lakes, etc., cited be-
fore.
tOn the correlation of the New York moraines with the raised
beaches of lake Erie, by Frank Leverett. Am, Jour. Sci., vol. L, 1895,
pp. 1-20.
JProc. A. A. A. S., 1888, p. 199.
§The Iroquois Beach, etc. Trans. Roy. Soc. Can., 1889, p. 132,
120 The American Geologist, February. i8»
In 1886, after the third survey of Niagara falls (by Prof.
Woodward), the rate of recession was found to be much
greater than had formerly been supposed. Prof. Gilbert then
made a short study of the falls, the conclusions concerning
which are summed up as follows by that author:* **The
problem admits of expression in an equation:
Age of gorge equals Length of gorge
Rate of 1
recession of falls.
- Effect of antecedent drainage.
_ ** **
thinner limestone.
it
" thicker shales.
— **
" higher fall.
— **
" more floating ice.
± "
" variation of detrital load.
± "
" chemical changes.
± "
" changes of river vohune.
**The catchment basin was formerly extended by includ-
ing part of the area of the ice sheet ; it may have been abridged
by the partial diversion of Laurentian drainage to other
courses." He had divided the length of the gorge by the
maximum rate of recession, finding the product to be 7,000
years. If the equation be carefully examined, together with
the cited quotation, all the important changing effects in the
physics of the river would lessen the estimated age of the
cataract below 7,000 years, except the effect "by partial diver-
sion of the Laurentian drainage to other courses," of which
no evidence was suggested; nor was any lengthening of time
shown as necessary, by the long inferior hight of the falls.
Henceforth, Prof, (jilbert was naturally quoted as an author-
ity that the age of the falls was only 7,000 years. This con-
clusion did not satisfy the writer, who from the evidence of
the beaches, especially the Iroquois, f found that the rate of
recession must have been for long ages much less than now,
on account of the inferior hight of the falls: and also on ac-
count of the greatly diminished volume of water, owing to the
overflow of the upper lakes to the northeast, until in recent
days. ]>ut how much of the work of the falls had been done
♦The Place of Niagara Falls in Geological History. G. K. Gilbert.
Proc. Am. Adv. Sci., vol. XXXV. 1886, pp. 222-22}^'
tSec Trans. Roy. Soc. Can., i88q, p. 132: and Proc. A. A. A. S..
1888, p. 199.
Researches relating to the Great Lakes. — Spencer. 1 2 1
before the upper lakes were turned into the Niagara drainage,
for a long time seemed undeterminable, until the features of
Foster's flats were used for measuring the amount of work
performed in that early episode. This standard has since
been confirmed by other phenomena not yet published; and
from a different standpoint the distance of the early recession
has been agreed to by Prof. Gilbert, who now considers the
age of the falls far greater than that formerly suggested by
his paper in 1886. From all the available data up to 1894,
the writer computed the age of Niagara falls at 32,000 years.*
Of the various episodes, that of the cataract passing the nar-
rows of the whirlpool rapids still seems the most difficult of
explanation ; but the writer has recently found that the nar-
rows record a second reduction in the amount of fall in the
river, before the present descent was established, thus retard-
ing the recession along this section of the gorge, and increas-
ing in part the time compensation for the reduced amount of
work performed. However, further discoveries are neces-
sary to fully explain the phenomenon of the narrows. It now
seems probable that the error in determining the time re-
quired for the recession of the falls through the section of the
whirlpool rapids would not affect the computation of the
whole age of the river by more than a few per cent.
No less important than the determination of the age of the
river was that of the date when the waters of the Algonquin
basin (Huron, Michigan and Superior) were first turned into
the Niagara drainage, owing to the warping of the land,
with the greatest rise occurring along an axis trending N. 28°
E.f The date of the diversion of the waters of the upper
lakes from the Ottawa to the Niagara valley has been com-
puted by the writer at 7,200 years. This result was obtained
from the mean of three distinct methods of computation,
varying from 6,500 to 7,800 years .J- Mr. F. B. Taylor's more
recent estimate gives the range of from 5,000 to 10,000 years.
Niagara as a time piece would be incomplete without indi-
* Duration of Niagara Falls. Am. Jour. Sci., vol. XLVIII, .1894.
PP- 455-472.
tThis direction occurs e?st of Georgian bay, while at the end of lake
Ontario the direction of rise is N. 25° E. See papers by the writer
cited before.
JSee Duration of Niagara Falls, cited before.
122 Tlie American Geologist. February, ift9b
eating the changes in the near future. From the northeast-
ward tilting of the lake region, it was computed that in 5,000
years, not merely Niagara falls would cease to exist, but also
that the drainage of the deepest part of the Niagara river at
Buffalo (45 feet) would be reversed and turned into lake
Erie, whose outlet would then be through lakes Huron and
Michigan into the Mississippi river by way of Chicago. This
inference was based upon the long delayed discovery of the
rate at which the earth's crust has been rising in the lake
region, — which was found to be for the Niagara district 1.25
feet per century more than the rate of rise at Chicago.* With
this determination it was easy to calculate the rate of terres-
trial deformation for other regions, — thus northeast of lake
Huron the rise has been found to be two feet per century, and
north of the Adirondacks, the warping is progressing at 3.75
feet in a hundred vears.
The rate of deformation of 1.25 feet per century, in the
Niagara district, was the minimum calculation, with a possible
maximum of about 1.5 feet per century. The approximate
correctness of the determination has just been confirmed by
a paper presented to the American Association, by Prof. G. K.
Gilbert, immediately before this communication was read.t
He had used the bench-marks at various localities where the
fluctuations of the lake levels have been registered the last 20-
37 years. While the recorded measurements vary from about
one to two and a half inches during the periods of observa-
tion, they have been extended over the lake region, with re-
sults closely agreeing with the previous determinations of the
writer. This will be better understood using Prof. Gilbert's
application — namely, — that in 500-600 years, the Erie waters
would be on a level with those of lake Huron — in 1,000 years
they would overflow the natural divide near Chicago — in 2,500
years, the waters would cascade into the Niagara gorge only
during high water — and in 3,000 years, the falls would be en-
tirely drained. These changing conditions, based upon the
writer's previously discovered rate of terrestrial deformation,
would take — 720 years for the Erie and Huron waters to be
♦See Duration of Niagara Falls, cited before.
t Modification of the Great Lakes by earth movements. Nat. Geog.
Mag., vol. VIII, 1897. pp. -233-247.
Editorial Comment. 123
on the same level; 1,280 years for the overflow into the Missis-
sippi drainage (the artificial canal would reduce this estimate
to 720 years) ; and 2,560 years for the general drainage of the
lakes into the Mississippi. In 5,000 years, the whole river as
far as Buffalo would be drained towards the south.
In spite of taking the minimum rate of recession and the
probable errors the closeness of these results satisfactorily
confirms many of the calculations based upon Niagara as a
geological chronometer.
This paper, giving the principal results of investigations
into the lake history, thus shows the writer to have been
greatly affected by the studies of his co-workers. Indeed all
of the researches by the different observers have been very
much dove-tailed, so that our present knowledge of the his-
tory of the great lakes and Niagara falls is the result of the
labors of many individuals. Besides the names of those
already mentioned, we should add those of Shaler, Tarr,
Wright, Russell, Upham, Kibbe, Lincoln, Brigham and Sco-
vill, with the names of Hall and Lyell, too well known to need
special mention.
To complete the review mention should be made of the
writings of Mr. F. B. Taylor, in connection with his important
survey of the Nipissing outlet of the Algonquin basin, and of
the dissected shore lines of the upper lakes; and of the im-
portant investigation of Central New York by Prof. Fairchild.
EDITORIAL COMMENT.
* A Case of Geological Parasitism.
Notwithstanding the grand success, on the whole, of the
Seventh International Congress of Geologists that convened
at St. Petersburg last August, there were certain features
which tended to interrupt considerably the general good feel-
ing that otherwise prevailed during the series of most enjoya-
ble meetings, and which gave rise to not a little adverse com-
ment. It is not that the same tendencies did not exist at pre-
vious sessions, but that at the last one they became so promi-
1 24 The American Geologist, February. !»»»
nent as to call for their serious consideration and removal, if the
future gatherings are to be successful. The extraordinary gen-
erosity of his Imperial Highness the Czar and of the people
throughout every part of the great Russian empire in provid-
ing means to make the sojourn of the scientific visitors one to
be forever remembered by them with unalloyed pleasure,
brought forth an unusually large number of persons who
wished to take advantage of the "cheap rates'' to "do" a coun-
try that is out of the path of the average tourist — people who
not only had no just claim to being professional geologists,
but were not even in sympathy with the science. To this
sort of unpleasant imposition no other term than that of para-
sitism can be appropriately applied.
Of recent years there has been an increasing tendency for
persons entirely uninterested in the various subjects to take
advantage of scientific meetings on account of the special in-
ducements offered to take desirable trips at small expense.
Not the slightest objection can be offered to the attendance,
at the sessions, of non-professional persons who are really in-
terested in the different themes, or even to the presence of un-
sympathetic individuals ; all scientists are broadly charitable in
this respect. It is, however, the grossest kind of imposition,
to say the least, for these scientifically unsympathetic, though
perhaps at times thoughtless, people to rush headlong and
hoggishly, as they did in Russia, into all the excursions and
entertainments, often provided at great expense, crowding out
many who were eligible, causing no end of inconvenience,
trouble and confusion to the legitimate attendants, and creat-
ing the profoundest consternation among the entertainers.
This, in spite of the very plain, and yet perhaps too polite,
hints by the local committee, months in advance. Common
politeness should have clearly and unmistakably indicated the
proper course for these ineligibles to pursue. But the local
committee was gracious ; it swallowed the unexpected and bit-
ter dose as best it could, and put forth its very best efforts to
make the occasion pleasant for all — unwelcomed guests as
well as especially invited workers — even at an additional cost
of many thousand roubles.
Unfortunately the kindly actions of a local committee did
not universally prevail, and it will be many a long day before
Editorial Comment. 125
some of the intruders will care again to face the criticisms
received and so amply deserved. Much as direct snubbing is
to be regretted in any instance, it was a case that got beyond
human endurance. It will serve, however, as a wholesome
warning against the increase of similar parasitism in the
future. No doubt the experience will lead the next congress,
which convenes at Paris in 1900, to adopt early some rigid
restrictions as to who shall participate in the excursions and
entertainments that may be offered. Each nation, however,
moreover, should use its best endeavors not only to send its
best representatives as delegates, but should take proper
measures to induce all those who are not actually engaged in
geological work to have compassion enough on their country-
men not to disgrace them.
While the Americans were by no means the greatest sin-
ners, parasitism among them at the St. Petersburg meeting
was so prevalent that a repetition of it to the same extent will
cause Americans to lose their present creditable standing
among the geologists of the world. More than once during
their sojourn in Russia were the American geologists present
compelled to bow their heads in shame at the actions of their
countrymen who posed as scientists from the new continent,
but who had no right whatever to the courtesies that were
extended. Other nations were severely afflicted in the same
way, but that was no excuse for the existence of the scourge
among us. The extent to which the legitimate working geolo-
gists of America were made to suffer the stigma cast upon
them by their well-meaning, but perhaps thoughtless, asso-
ciates, is shown by the fact that out of the sixty credited to
America, no less than twenty-five had not the slightest excuse
for participating, further than attending the general sessions.
With certain other nations the percentages were even higher.
A hint as to the extent to which this was considered an extra
burden carried by the Russian people may be obtained from
the fact that out of about 900 who were members of the con-
gress, only 200 invitations to the reception at the Marble
palace were sent out by their Imperial Highnesses the Grand
Duke and Duchess, and it is not believed that the name of any
prominent geologist was omitted.
In order that the experience may not be repeated, it is
1 26 The American Geologist, February, i898
necessary to take certain precaution before the convening of
the next congress at Paris, three years hence. While the
French no doubt will see that the same condition of affairs
is not allowed to prevail, it is desirable for each nation to sup-
plement this effort so far as itself is concerned. The first
cause of it all, in the past, may be attributed directly to the
local committees ;though they are not to be blamed, however
much future committees may be open to criticism should they
not take warning in time to avoid the same pitfall.
The course to pursue is a simple one, notwithstanding the
fact that the life of the congress is not continuous. As the
next assembly, in 1900, is to be strictly a gathering of geolo-
gists, it is only necessary for the local committee at Paris to
send out invitations to those whom they know to be bona fide
workers in the science. The list may be prepared sufficiently
long in advance to be submitted for revision to the vice-
president of each country represented in the previous con-
gress. The application for membership of all others may be
referred in the same manner to the respective nations. An
ample as well as simple test of elegibility is found in the pub-
lished writings of the persons wishing to become members,
so also the imm ediate members of the families of participants
may be readily made associate members, with all privileges
except those of voting and participation in the excursions.
The suggestion of the last named restriction may sound some-
what severe, but in order to accomplish one of the principal
objects of the triennial gathering it is absolutely necessary to
limit the number of participants in the trips to the least possi-
ble number and to the strictly working geologists. The bur-
dens of past congresses have become at last too heavy to be
borne in the future. c. R. k.
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
Geological Survey of New Jersey, Annual Report for the Year i8g6.
John C. Smock, State Geologist. Pages xxviii, 377, with 24 plates and
a large map. Trenton, 1897.
The administrative report, by Prof. Smock, in 18 pages, gives a com-
prehensive outline of the work of the survey during 1896; and this is
followed by eight reports of its separate divisions.
Revieiv of Recent Geological Literature. 127
Prof. Rollin D. Salisbury and Mr. George N. Knapp present their
Report of Progress on the Surface Geology in 22, pages, with seven
plates. It is found that the Pensauken formation, which McGee and
Salisbury have pronounced to be the northward continuation of the
Lafayette formation in the more southern states of the Atlantic coastal
plain and Gulf region, when traced into the northeastern part of Mid-
dlesex county, adjoining the glacial drift, becomes in many places un-
stratified and incloses glacially striated stones, being almost like till.
It was formed contemporaneously with an early extension, perhaps the
maximum^ of the North American ice-sheet.
Because of this relationship, it seems to me worthy of inquiry
whether the correlation with the southern coastal plain formations studied
by McGee, Darton, Clark, and others, may be better given as follows:
I. The clay and sand beds of the lower part of the Beacon Hill series,
probably marine Miocene; 2. The upper Beacon Hill gravel, equivalent
with the Lafayette formation ; 3. The great erosion interval between
the time of the Beacon Hill gravel and the Pensauken epoch, equiva-
lent with the Ozarkian epoch of Hershey, completing the Lafayette
period; 4. etc. The Pensauken, Jamesburg. and Trenton formations,
with the Philadelphia brick clay, all of Glacial age, the first belonging
to a time of high continental elevation, and the others to the Late
Glacial or Champlain epoch of continental depression, together repre-
senting the Columbia series in its high level and low level phases. This
view, with reference of all the Yellow Gravel series in New Jersey to
fluvial deposition, not in the sea, was suggested by the present reviewer
in the American Geologist for March, 1895 (vol. xv, p. 204).
Dr. Henry B. Kiimmel, in Part II. (pages 25-88, with plate viii).
reports the progress of his field work and studies of the Newark system.
The sedimentary rocks of this system are divided, in ascending order,
into the Stockton, Lockatong, and Brunswick series. Exclusive of the
intruded sheets and overflows of trap, the thickness of these three divis-
ions is estimated to be, respectively, 4,700, 3,600, and 12,000 feet, giving
a total of 20,300 feet.
Part III is Prof. J. E. Wolff's Report on Archean Geology (pages
89-94, with plate ix), dealing with the eruptive rocks of Sussex county.
Part IV, by Lewis Woolman, includes reports on artesian wells
(pages 97-200), and notes on the stratigraphy and fossils of the Fish
House black clay and associated gravels, near Camden and Philadelphia,
which are referred to the Pensauken series. The fossils comprise
Vnio and Anodonta species, Equus compiicatus Leidy, flattened
tree and other plant stems, and peat. Mr. Woolman also notes the
occurrence of dinosaur and molluscan fossils in Cretaceous clay marls.
;ind of Fulgur and Venus casts in Beacon Hill sands near Millville,
about 40 miles south of Camden.
The remaining parts of this volume treat of the flood of February
6th, 1896, in northern New Jersey, by C. C. Vermeule; of drainage of
the Newark and Hackensack tide-marshes, also by Mr. Vermeule, with
a large folded map: of the iron-mining industry, by George E. Jenkins;
128 The American Geologist. Febraan, iw^*^
and of forestry, with notes of European countries, by John GifTord.
The vokime is completed with mining statistics for i8q6, the catalogue
of publications of the survey, and an index. w, u.
Report att the Doobattnt, Kazan and Fergusatt Riversand the Xorth-
west Coast of Hudson Bay^ and on Two Overland Routes from Hudson
Ray to Lake Winnipeg. By J. Burr Tyrrell. Part F, of the Annu-
al Report of the Geological Survey of Canada, vol. IX, for 1896. Pages
218, with eleven plates and three maps. Ottawa, 1897.
The routes of travel here described extend across an area of about
200,000 square miles, from near the east end of lake Athabasca north-
ward and eastward to Chesterfield Inlet and the west side of Hudson
bay. The explorations were carried on in the years 1893 and 1894, the
author's return from each expedition being in winter by sledging over
frozen rivers and lakes between Fort Churchill and Winnipeg. The
country consists mainly of granitic rocks and granitoid gneisses, of
Laurentian age, with several large Huronian tracts; but Cambrian sand-
stone and conglomerate adjoin Athabasca lake and also extend nearly
200 miles west from the head of Chesterfield Inlet.
On the treeless Barren Lands of the north, which comprise thf
greater part of the country, immense herds of caribou pasture in the
summer, retiring southward to the woods in winter. One herd, of whicli
two photographs arc given, was estimated to number between one and
two hundred thousand.
The contour is only slightly diversified. It presents mostly a vast
undulating plain, having an inland altitude of 1,000 to 1,500 feet, with
rare hills a few hundred feet higher, and declining gradually eastward to
the shores of Hudson bay. Much of the surface is sandy or stony till,
with only shallow and ill-defined valleys, of which the author says:
"Since the disappearance of the Keewatin glacier, the streams have had
very little power of erosion, for they are frozen up most of the year,
and each spring, as they open, the ice packs the boulders that fonn their
banks into massive walls which resist erosion almost as effectually as the
unbroken rock itself. Besides this, the time since the disappearance of
the glacier may not have been very long."
The courses of glacial striation and transportation of drift imply, a?
the author shows, that the ice-sheet in its departure became divided into
several separate areas. The reviewer thinks, however, that the maxi-
mum extensions of the confluent North American ice-^heet were nearly
contemporaneous from its Laurentide, Keewatin and Cordilleran centers
of outflow. Tlie observations of Chamberlin, Todd, and the writer of
this review, prove that continuous marginal moraines pass from the
Laurentide to the Keewatin ice front in Minnesota and the Dakotas.
south of lake Agassiz and also from the east to the west sides of that
glacial lake.
Marginal moraines and eskers were noted by Tyrrell in many places
throughout the country here reported. After the ice slieet had mostly
disappeared, the land west of Hudson bay lay nearly 500 feet lower than
Rcvkw of Recent Geological Literature. 129
now, and successive marine shore lines mark stages of the ensuing
cpeirogenic uplift of the land to its present hight.
Three appendixes are included at the end of this report. The first
gives the Chippewyan names of places; the second is a vocabulary of
words used by the Inland Eskimos who live on the Kazan and Ferguson
rivers; and the third is a list of the plants collected (excepting algae and
fungi), as determined by Prof. John Macoun, with notes of their
localities. w. u.
Batesville Sandstone of Arkansas ^ By Stuart Weller. (Trans.
New York Acad. Sci., vol. XVI, pp. 251-285, 1897.)
Until very recently the Ozark region was one of the largest tracts
in the country that remained a veritable "terra incognita" to geologists.
Of late years, however, workers in different parts of the region brought
out, more or less completely, local successions of formations, but these
were never paralleled exactly with those of neighboring districts. This
was especially true of the later Paleozoic deposits. On the north side
of the great dome the formations just referred to were finally brought
into strict accordance with the standard sections of the Mississippi
basin. On the south side of the uplift, in Arkansas, and Indian terri-
tory, little effort was made to compare the various portions of the
general section of that region with the more typical localities to the
north. In the southern district, also, an entirely new set of names was
applied, which in the absence of exact data and knowledge regarding
the northern representatives precluded any but the most general com-
parisons of their probable equivalents. About the only formation of the
lower Carboniferous, for instance, that was correlated, with any degree
of certainty, with the northern sections was the Boone chert, which was
thought to represent, in part at least, the well known Burlington lime-
stone. It was at a subsequent time that the Kaskaskia division was
clearly recognized in northwestern Arkansas and the adjoining part of
Indian territory, with indications of the St. Louis limestone nearby in
Missouri; also farther eastward on the tributaries of the White river
the Kinderhook was definitely made out, so that all four of the main
subdivisions of the Mississippian series, or Lower Carboniferous, were
differentiated around the entire northern two-thirds of the Ozark uplift.
Much of the Arkansas part of the dome remained uncorrelated.
It is, then, with special welcome that the results of the recent work
of professor Weller, in the Carboniferous of northeastern Arkansas, are
received. Under the modest title of *'The Batesville Sandstone of
Arkansas" appears one of the most important contributions to our
knowledge of the geology of the Ozark region that has yet appeared.
The succession of the Carboniferous-, as represented in the Batesville
district and of northern Arkansas generally is shown to be as clearly
defined, and with the same subdivision, as in the typical localities along
the Mississippi river. The following is the table of equivalent for-
mations:
130
The American Geologist.
February. 18»<
Batesville Section.
Ttpical Section.
Boston limestones and shales.
BatesvUle SHudstone.
Spring Creok limostono and slialos.
Boone cherts.
St. Joo marblf .
Sylamoro sandstone.
Kaskaskia limestone and shales.
Auz Vases sandstone.
St. Louis limestone.
Ozark [AuRUMta] limestone.
Kinderhook beds.
Basal sandstone of Kinderhook.
Regarding these, the author says, in conclusion:
"The BatesTille sandstone has the same stratigraphical position in the Bates-
ville section which the Aux Vases sandstone occupies in the typical section, and the
litholo|?ic characters of the two formations are similar. No fossils have as yet boeu
found in the Aux Vases sandstone, but if a fauna were found a mingling of St. Louis
and Kaskaskia species, such as are present in the Batesville sandstone fauna would
be looked for.
'^The strata of the Batesville section wore deposited otf the southern shore of the
same land, from whose eastern shore the strata of the typical section were laid
down, hence it is not surprisinjf? to find the sequence of the strata almost identical in
the two sections.
"The Mississippian serli>s was typically deposited not only along the line of the*
present Mississippi river, but off the shores and wholly surrounding the ancient
Ozark Island. The deposition varied more or less off the different shores of the
island, especially during the latter half of the period, when the body of land ceased
to bo entirely surrounded b^ water, by being i>artially or wholly joined to the main-
land toward the north ; the lower formations, however. Included in the Kinderhook
and Osage groups, may bo expected to have a similar development on all sides of the
ancient island."
The paper contains the descriptions and ilhistrations of a number of
new species of fossils that form a part of a rather extensive fauna which
was found near the base of the sandstone, and also critical annotations
on these and a number of others. The relations of the faunas of the
Batesville sandstone and of the Maxville limestone of Ohio are also
discussed. The brief clear statement regarding the stratigraphy of the
Batesville region, and of the typical Mississippian section makes the
theme complete and adds greatly to the usefulness of the account.
There are one or two points m the article that might be open to
criticism. One is the use of the word "group" in a sense that is now
generally abandoned by geologists, who have given it an exact meaning
in another connection — for a larger "group" of formations; though it
is recognized that many paleontologists still persist in applying the term
in a general, indefinite or loose way. Another point concerns the
myth of the Ozark isle. Of late the "Ozark island" has been also used
by the same author, as well as others, as the foundation of some
attractive and far-reaching generalizations regarding the distribution of
Devonian and early Carboniferous faunas, and of the land and water
areas of that time. The idea of the existence, from Cambrian times,
of an Ozark island was promulgated by some of the older geologists,
who visited the region when our knowledge of the geological events
that transpired in that part of the present continent was very much less
complete than now. Although of late special attention has been re-
peatedly called to the fact, and ample evidence set forth, it seems well
Authors' Catalogue, 131
nigh impossible to eradicate the antiquated views which still continue
to creep into the current literature relating to the region. Every bit
of evidence that has been obtained in regard to the geological history
of the Ozark uplift points conclusively to the fact that not only was the
dome or "island" character of the area not acquired until a very late
date, geologically speaking, during Tertiary times — the older formations
having been removed down to the Silurian or Cambrian during the
Cretaceous • base-leveling process that prevailed over a large area of
this portion of the continent:--but that during the later Paleozoic, up to
the epoch in which the coal deposits were laid down, sedimentation was
uninterrupted over the entire region. In substantiation of the state-
ment that the Devonian and Lower Carboniferous (up to the Kaskaskia)
strata once extended unbrokenly over the whole of the present Ozark
dome, but were almost entirely removed through subsequent erosion at
a later date, one has only to point to the fact that remnants of highly
fossiliferous beds of undoubted Devonian and Lower Carboniferous age
are still found on the highest portions of the central parts of the uplift.
C« K. IC.
MONTHLY AUTHORS^ CATALOGUE
OF American Geological Literature,
Arranged Alphabetically.*
Ball, T. H.
The Lake Michigan and 'Mississippi Valley water shed. (Indiana
Acad. Sci., Proc. 1896, pp. 72-73, 1897.)
Ball, T. H.
Some notice of streams, springs, wells and sand ridges in Lake
county, Indiana. (Indiana Acad. Sci., Proc. 1896, pp. 73-75, 1897.)
Carter, O. C S.
The upper Schuylkill river. (14 pp.; reprint from Jour. Franklin
Inst, Nov. 1897.)
Chamberlln, T. C.
Supplementary hypothesis respecting the origin of the loess of the
Mississippi valley. (Jour. Geol., vol. 5, pp. 795-802, Nov.-Dec. 1897.)
Chamberlln, T. C.
Studies for students. The method of multiple working hypotheses.
(Jour. Geol., vol. 5, pp. 837-848, Nov.-Dec. 1897.)
Corthell, E. L.
The delta of the Mississippi river. (Nat. Geog. Mag., vol. 8, pp.
351-354, Dec. 1897.)
Cragln, F. W.
Discovery of marine Jurassic rocks in southwestern Texas. (Jour.
Geol., vol. 5, pp. 813-820, Nov.-Dec. 1897.)
•This list includes titles of articles received up to the 20th of the preceding
month, including general geoloKy, physioirraph.v, i)aleontoloKy, petrology and
mineralogy.
132 The American Geologist, February, ises
Dall, W. H. (Guppy, R. J. L., and)
Descriptions of Tertiary fossils from the Antillean region. (U. S.
Nat. Museum, Proc., vol. 19, no. 11 10, pp. 303;33i, pis. 27-30, 1897.
Extras issued May 30, 1896.)
Daly, R. A.
Studies in the so-called porphyritic gneiss of New Hampshire. II.
(Jour. Geol., vol. 5, pp. 776-794, Nov.-Dec. 1897.)
Gilbert, G. K.
Joseph Francis James. (Am. Geo!., vol. 21, pp. i-ii, pi. i, Jan.
1898.)
Guppy, R. J. L. (and Dall, W. H.)
Descriptions of Tertiary fossils from the Antillean region. (U. S.
Nat. Museum, Proc., vol. 19, no. 11 10, pp. 303-331, pis. 27-30. 1897.
Extras issued May 30, 1896.)
Ingall, E. D.
Section of mineral statistics and mines. Annual Report for 1896.
(Geol. Surv. Canada, Ann. Rept., vol. 9 [1896], pt. S, 172 pp., 1897.)
IwasakI, C.
Aiidendiorite in Japan. (Jour. Geol, vol. 5, pp. 821-824, Nov.-Dec.
1897.)
James. J. F.
Sketch of, bv G. K. Gilbert. (Am. Geol. vol. 21, pp. i-ii, pi. i.
Jan. 1898.)
Merrlam, J. C.
The geologic relations of the Martinez group of California at the
typical locality. (Jour. Geol, vol. 5, pp. 767-77S1 Nov.-Dec. 1897.)
Preston, H. L.
On iron meteorites, as nodular structures in stony meteorites. (Am.
Jour. Sci., ser. 4, vol. 5, pp. 62-64, Jan. 1898.)
Salisbury, R. D.
On the origin and age of the relic-bearing sand at Trenton, N. J.
(Science, n. ser., vol. 6, pp. 977-981, Dec. 31, 1897.)
Schuchert, Charles.
On the fossil phyllopod genera, Dipeltis and Protocaris, of the family
Apodida?. (U. S. Nat. Museum, Proc, vol. 19, no. 11 17, pp. 671-670,
pi 58. 1897. Extras issued May 30, 1897.)
Smith, W. S. T.
A note on the migration of divides. (Jour. Geol, vol 5, pp. 809-812.
Nov.-Dec. 1897.)
Spencer, J. W.
On the continental elevation of the Glacial period. (Geol Mag., new
>cr.. dec. 4. vol. 5, pp. 33-38, Jan. 1898.)
Squier, G. H.
Studies in the driftless area of Wisconsin. (Jour. Geol, vol 5, pp.
^25-836, Nov.-Dec. 1897.)
Stone, G. H.
The granitic breccias of the Cripple Creek region. (.\m. Jour. Sci..
ser. 4, vol. 5, pp. 21-32, Jan. 1898.)
Correspofidence^ 1 33
Tyrell, J. B.
Report on the Doobaunt, Kazan and Ferguson Rivers and the north-
west coast of Hudson bay and on two overland routes from Hudson
bay to lake Winnipeg. (Geol. Surv. Canada, Ann. Rept, vol. 9 [1896].
pt. F, 218 pp., II pis., 3 maps, 1897.)
Wadsworth, M. E.
Zirkelite — a question of priority. (Science, n. ser., vol. 7, p. 30, Jan.
7, 1898.)
Walcott, C. D.
Cambrian Brachiopoda: Genera Iphidea and Yorkia, with descrip-
tions of new species of each, and of the genus Acrothele. (U. S. Nat
Museum, Proc, vol. 19, no. 1120, pp. 707-718, pis. 59-60, 18^7. Extras
issued Aug. 27, 1897.)
Weller, Stuart
Cryptodiscus, Hall. (Jour. Geol., vol. 5, pp. 803-808, Nov.- Dec.
1897.)
White, I. C.
The Pittsburg coal bed. (Am. Geol., vol. 21, pp. 49-60, Jan. 1898.)
White, T.G.
A contribution to the petrography of the Boston basin. (Boston
Soc. Nat. Hist, Proc, vol. 28, no. 6, pp. 1 17-156, pis. 1-5, Dec. 1897.)
Whitfield, R. P.
Observations on the genus Barrettia, Woodward, with descriptions
of two new species. (Am. Mus, Nat Hist, Bull., vol. 9, pp. 233-246,
pis. 27-'^, Nov. 19, i898l)
WIeland, G. R.
The protostegan plastron. (Am. Jour. Sci., ser, 4, vol. 5, pp. 15-20,
pi. 2, Jan. 1898.)
Winchell,N. H.
Determination of the feldspars, (Am. Geol, vol. 21, pp. 12-49, pis,
:^-8, Jan. 189&)
CORRESPONDENCE.
Zirkelyte: A Question of Priority. In the Minera-
hgical Magazine y volume XI, pp. 86-88 (read June 18th, 1895^
is described a new mineral containing zirconium, titanium, lime, iron,
etc., under the name of zirkelite. This paper was prepared by my
friend, Dr. E. Hussak, and by Mr. G. T. Prior.
Later, Mr. Prior (1. c. pp. 180-183, read Nov. 17, 1896) published
an analysis of the Same mineral.
I wish to protest against the use of the name zirkelite for this
mineral on the ground of the prior use of it to designate a commonly
occurring rock belonging to the basaltic family.
When two subjects are so intimately connected as mineralogy and
petrography, it does not seem to be for the interest of science that
1 34 The American Geologist, February, i»w
names should be duplicated in them. So true is this, that I abandoned
the name rosenbuschyte, which I had given to a class of rocks in honor
of professor Rosenbusch, because only a few weeks previously it had
liCen employed to designate a new mineral.
The term zirkelyte was used by me in 1887, or seven years before
it was taken by Messrs. Hussak and Prior. (See "PreHminary Descrip-
tion of the Peridotytes, Gabbros, Diabases and Andesytes of Minne-
sota." Bulletin No. 2. Geological Survey of Minnesota, 1887, pp.
30-32). It was used to designate the commonly occurring altered con-
ditions of basaltic glassy lavas which are often called diabase-glass, etc.
Zirkelyte occurs forming the entire mass of thin dikes, and the exterior
parts of many dikes of diabase and melaphyr, as well as the surface of
old lava flows like the melaphyrs and diabases of lake Superior, New-
foundland and elsewhere. Zirkelyte holds the same relation to tachylytc
that diabase and melaphyr do to basalt, i. Ci, an older and altered type.
The macroscopic and microscopic characters of this rock were given in
the locality cited above.
The term zirkelyte was again used in the same way in my "Report
of the Geological Survey of Michigan" for 1891-1892; (1893, pp. 90, 97,
138, etc).
It was also published in my classification of rocks given in the cata-
logue of the Michigan College of Mines (Michigan Mining School).
1891-1892. p. 104; 1892-1894, Table XI; 1894-1896, Table XI.
Further, the term zirkelyte is defined in accordance with my usage
in Loevvinson-Lessing's "Petrographischcs Lcxikon," 1893, p. 252; and
accounts of it are given in the Neues Jahrbuch fiir Mineralogie, 1893.
II, p. 292, and in Kemp's ''Handbook of Rocks," 1896, p. 170.
Michigan College of Mines, Dec. 8, i8gy. M, E. Wadsworth.
Houghton, Michigan.
PERSONAL AND SCIENTIFIC NEWS.
Mr. S. a. Miller, of Cincinnati, Ohio, died on Dec. 19,
a^ed 61 years. He is known for his work in paleontology,
and more especially for his book entitled "North American
(ieology and Palaeontology," which appeared in 1889. Two
appendices to this book have been published. During the
last few years Mr. Miller contributed many paleontological
articles to the Bulletin of the Illinois State Museum of Nat-
ural History.
Mr. Noah F'ields Drake, a graduatcstudcnt of geology at
Stanford University, has accepted a position as professor of
mining engineering and geology at Tien Tsin' University,
China.
Prof. N. H. WiNCHELL, editor of this journal, sailed from
Xew York for Havre on Jan. 15. He expects to spend several
Personal afid Sciefitific News. 135
months in Paris, engaged in investigating the petrology of
the crystalline rocks of northeastern Minnesota. The results
of his work are to be published in one of the reports of the
Geological and Natural History Survey of Minnesota.
The Geological Society of Washington at its meeting
of December 22rd, elected the following officers for the
ensuing year: President,, Arnold Hague; vice-presidents, J.
S. Diller and Whitman Cross; treasurer, M. R." Campbell:
secretaries, C. Willard Hayes and T. W. Stanton; members-
at-large of council, S. F. Emmons, G. P. Merrill, W. H.
Weed, David White and Bailey Willis.
The Geological Society of America at its meeting held
in Montreal the last week in December, elected the following
officers: President, J. J. Stevenson; first vice-president, R. K.
Emerson; second vice-president, G. M. Dawson; secretary,
H. L. Fairchild; treasurer, I. C. W^hite; editor J. Stanley-
Brown; librarian, H. P. Gushing; councillors, W. M. Davis,
Robert Bell and M. E. Wadsworth. The membership roll of
the Society, including four fellows elected at this meeting,
contains 246 names. The treasurer's report shows that the
Society's financial condition is prosperous, thus making it
])ossible to illustrate more fully future publications.
New York Academy of Sciences, Section of Geology, Dec.
20th, 1897. — The first paper of the evening was by Mr. Arthur
Hollick, entitled "Recent Explorations for Prehistoric Im-
plements in the Trenton Gravels, Trenton, X. J.'* Dr. Hol-
lick gave in his paper a summary of the present understand-
ing of the artefacts found in the Trenton gravels, a more com-
plete statement of which has already been published in
Science for November 5, 1897. The second paper of the
evening was by Prof. J. F. Kemp, entitled "Some Eruptive
Rocks from the Black Hills.'' Prof. Kemp summarized the
geological features and history of the Black hills, and gave
a bibliography of the works concerning these deposits. He
then mentioned the occurrence of some leucite bearing rocks,
in the northern part of the hills, similar in character to those
which occur in but few other places in this country, as in
Wyoming, Montana, Lower California, and Xew Jersey, near
the Franklin furnace. Richard E. Dodge Secretary.
The Minnesota Academy OF Natural Sciences at its
last regular meeting (Jan. 5) elected the following officers for
the year t8q8: Prof. N. H. Winchell, president; Prof. D. T.
MacDougal, vice-president; Mr. A. D. Roe, recording secre-
tary; Dr. C. P. Berkey, corresponding secretary; Mr. E. C.
Gaic, treasurer. At this meeting steps were taken looking to-
ward an at least temporary change from the former monthly
meeting to more important meetings to be held less frequently.
136 The American Geologist. February, law
It is possible that one meeting a year will be held away from
Minneapolis, the home of the Academy. On Dec. 28, 29 and
30, meetings in celebration of the twenty-fifth anniversary of
the Academy were held, at which twenty papers were pre-
sented. Among these the following pertained to geology:
"On a little known larviform crinoid from the lower Paleozoic, and
comparison with the living Antedon," by F. W. Sardeson, who. dis-
cussed more particularly the origin of the centro-dorsal plate of Ante-
don, tracing it apparently to three, five and six infrabasal plates, respec-
tively, in Paleozoic crinoids.
"The glacial lake Agassiz," by Warren Upham. The facts pre-
sented are found in the author's detailed report on this subject (Mon.
25 of the U. S. Geological Survey.)
"Volcanic fragmental rocks at Taylors Falls, Minnesota," by C,
B. Berkey. This subject is discussed in an article by the author in the
December number of this journal.
"The recession of the glacier from the Lake Superior region." by
A. H. Elftman. The substance of this paper can be found in the author's
article in this number of this journal.
"Significance of the fragmental eruptive debris at Taylors Falls,"
by N. H. Winchell. The author regards this eruptive debris as in
the main an oceanic deposit, forming, in part at least, a true basal con-
glomerate. Thus the diabase flows at Taylors Falls are separated into
two parts by an interval of erosion followed by one of oceanic deposi-
tion. This unconformity and the basal conglomerate are correlated with
similar phenomena in the Lake Superior region which enable us to
separate the Keweenawan eruptives into a lower (Norian) and ail upper
scries.
"Field notes in New Mexico geology," by C. L. Herrick. Some
of the more important and interesting points in the geolo^ of this
district were discussed and especial attention was called to points which
offered promising fields for investigation.
"The drift in southwestern Minnesota and northwestern Iowa," by
H. F. Bain. Detailed observations in Plymouth county, Iowa, and
the surrounding districts, showing the presence of several till, gravel
and loess deposits, were given and the following preliminary interpre-
tation was presented: (i) Kansan drift; (2) lowan drift; (3) high level
gravels connected with Wisconsin moraines; (4) erosion of river
valleys; (5) sheet loess; (6) Anadonta terrace (?); (7) Missouri River
loess proper; (8) Later terraces in the loess; (9) Wisconsin gravel trains
proper.
"The end of the ice age in Minnesota." by Warren Upham. The
author presented the main facts of the ice retreat across the state,
dwelling chiefly on the series of terminal moraines and the larger glacial
lakes. Of the latter the two lakes in the Minnesota River valley were
especially discussed.
"Certain resemblances between the Archean in Minnesota and in
Finland," by N. 11. Winchell. The resemblances between the Archean
of these two localities both in sequence of events and in lithology, were
shown to be comparatively close and the Minnesota series was more
especially discussed. The sequence in this state is as follows, beginning
with the most recent: (i) eruptive granite, at Snowbank lake and on
the Giants range: (2) Upper Kcewatin sediments, separated by an
unconformity from (3) eruptive granite, at Saganaga lake; (4) Lower
Kcewatin or Kawishiwin sediments and contemporary eruptives; the
rocks of this age consist very largely of "greenstones" most of which
the author regards as water deposited fragmental volcanic debris.
Persofial atid Scientific News, 137
^'Relations of the Saganaga granite to the surrounding rocks," by
U. S. Grant. Only that part of the granite lying in Minnesota (at the
northwestern corner of Cook county) was discussed. The granite lies
unconformably below the Animikie on the southeast, is intrusive into
the ''greenstones" on the south, which are also unconformable below
the Animikie, and is unconformable below the Upper Keewatin on the
west. Attention was called to the fact that a very large portion of the
"greenstones" of this part of the state shows no evidence of having
been deposited in the water, and also to the probability of the separa-
tion of the Lower Keewatin into two unconformable series, both of
which contain much "greenstone." The author regards the "green-
stones" immediately adjoining the Saganaga granite on the south, and
also those just south of the Basswood granite, a& probably belonging
to the lower series (Basement Complex), while the "greenstones" as-
sociated with the jaspilytes and iron ores of the Keewatin are regarded
mainly as eruptives of later date than the jaspilytes of the upper series.
A Geological Survey OF the South African Republic
has recently been decided upon by the government of that
state and has been placed under the direction of Dr. G. A. F.
Molengraaff i as state geologist. The results of this survey will
be published by means of annual reports and from time to
time of separate papers, accompanied by maps. A geological
museum and a library will be established at Pretoria in con-
nection with the survey.
Das Antlitz der Erde, by Ed. Suess, has been translated
into French under the direction of Emm. de Margerie. The
translation is entitled **La Face de la Terre," and it has an
introduction by Marcel Bertrand. This work is published by
Armand Colin & Co. (5 rue <le Mezieres, Paris), and the first
volume has recently been issued.
The Marsh Paleontological Collections.
At the meeting of the Yale Corporation, held on the 13th
inst., O. C. Marsh, professor of paleontology, formally pre-
sented to the University the valuable scientific collections be-
longing to him, now deposited in the Peabody Museum.
These collections, six in number, are in many respects the
most extensive and valuable of any in this country, and have
been brought together by Prof. Marsh at great labor and
expense, during the last thirty years. The paleontological
collections are well known, and were mainly secured by Prof.
Marsh during his explorations in the Rocky mountains. They
include most of the type specimens he has described in his
various publications.
The collection of vertebrate fossils is the most important
and valuable of all, and includes, among many others, (i) the
series of fossils illustrating the genealogy of the horse, as
made out by Prof. Marsh, and accepted by Huxley, who used
it as the basis of his New York lectures; (2) the birds with
teeth, nearly two hundred individuals, described in Prof,
^larsh's well-known monograph "Odontornithes"; (3^ the
1 38 The American Geologist. February, i8a»^
gigantic Dinocerata, several hundred in number, Eocene
mammals described in his monograph on this group; (4) the
Biontotheridae, huge Miocene mammals, some two hundred
in number; (5) pterodactyles, or flying dragons, over six hun-
dred in number; (6) the mosasaurs, or Cretaceous sea-
serpents, represented by more than fifteen hundred individ-
uals; (7) a large number of dinosaurian reptiles, some of
gigantic size. Besides there are various other groups of mam-
mals, birds and reptiles, most of them including unique speci-
mens.
Additional collections comprise extensive series of fossil
footprints, invertebrate fossils, recent osteology, American
archeology and ethnology and minerals.
The main conditions of the gift, which is for the benefit
of all departments of the University, are that the collections
shall remain in a fire-proof building and under the control of
IVof. Marsh during his life; after that under the charge of the
trustees of the Peabody Museum, and, finally, that type speci-
iricns shall not be removed from the museum building.
From the scientific point of view the value of the collec-
tions is beyond price, each one containing many specimens
that can never be duplicated and already are of historical in-
terest. Altogether this is the most important gift to natural
rcience that Yale has vet received.
The Indiana Academy of Science held its thirteenth
annual meeting at Indianapolis, on Dec. 29 and 30. Eighty
})apers were presented, of which the following pertained to
Ideology :
"Formation of quicksand pockets in the blue clay of South Bend.'*
W. M. Whitten.
"Preliminary work for the approximate determination of the time since
tlie retreat cf the first great ice sheet." G. Culbertson.
"Some faults of Indiana Coal Measures." G. H. Ashley.
"A section from Hanover to Vincennes." J. F. Newsom.
"The Knobstone groups in the region of New Albany." J.F. Newsom.
"Notes on the geolog>- of Mammoth Cave." R. E. Call.
"The upper limits of the Knobstone in the region of Borden." L. H.
Jones.
"Four sections across the Knobstone group." L. F. Bennet.
"Notes on Indiana geology." J. A. Price.
"An old river channel in Spencer county." A. C. Veach.
THE
AMERICAN GEOLOGIST
Vol. XXI. MARCH, 1898. No. 3
GEOLOGY OF THE ST. CROIX DALLES. IL
By Charles P. Berket, MiDneapoIis.
(Plates XII aad XIII.)
Part II.— MINERALOGY.
Chapter I. LitJtology of the Sedimentary Rocks.
Magnesia7i Series. A description summarizing the
lithologic character of the Jordan sandstone and St. Law-
rence shales has been published by Hall and Sardeson.*
There are few things of sufficient note, in the very limited
extent of these rocks within this area, to demand extended
discussion. The St. Lawrence, however, at this locality pre-
sents a splendid development of alternating bands of sand and
green shale, as illustrated in an accompanying figure. The
hand specimens from which the photograph was taken were
obtained at the foot of the falls at Osceola and belong to the
St. Lawrence formation. It is especially noticeable that the
sandstone bands are quite pure and in shai;p contrast with the
green shale bands. This contrast holds good even w^here the
bands are very irregular. It seems to indicate that the orig-
inal material came either from two very different sources, or
at very different rates of accumulation, or that this was the
scene of greatly disturbed sedimentation, such as might be
occasioned by an unstable ocean current or in a shallow bay
subject to violent storms.
*Bull. Geological Society of America, vol. Ill, 1892, p. 345.
140 The American Geologist. March, i898
Mention is made of the sandstone conglomerate in another
chapter. The pebbles of this conglomerate are well rounded
and of the ordinary sandstone type. A few small grains of
diabase are found in it. The cementing substance is calcare-
ous, but it does not usually produce a rock of great resistance.
In the present condition of both pebbles and matrix a sand-
stone is formed which, in common with all the sandstones of
this area, is too friable for any but the most transient struc-
tures.
A specimen of quartzyte was taken from the St. Lawrence
near a contact of the sedimentaries with the diabase. But
such a development is extremely local in extent.
'Basal Sandstone Series, This term is used throughout
the paper for a group of sandstones,* shales and conglomer-
ates, situated between the St. Lawrence formation and the
underlying igneous floor. These sandstones and shales of
the St. Croix Dalles area, as is shown in a former chapter, are
separable into three lithologically well defined subdivisions,
the uppermost being a sandstone, the middle one composed of
a glauconitic sandstone and green shales, and the lowermost
including the calcereous, pyritiferous, and argillaceous shales.
But below all these, though not exposed in this area, is a thick
sandstone f which in many other localities constitutes more
than one-half of the total thickness of the series.J
The upper member, the Franconia sandstone, is a rather
fine grained quartz sandstone. The uniform white color
varying locally to brown or yellow through ferric oxide stains,-
the rather angular character of the grains, the porous and
friable nature of the stone, the development of minute mica-
ceous flakes among the sand grains, the complex veining pro-
duced locally by infiltrated iron oxide, a thick-bedded struc-
ture exhibited by exposed bluffs, thin seams of greenish clay
shale frequently magnifying the bedded appearance and the
general lack of calcareous matter are characteristic of the
*Owen: Geological Survey of Wisconsin, Iowa and Minnesota,
1852, p. 49.
Chamberlin; Geol. Wis., vol. IV, 1882, p. 39.
Winchell: Final Report Minn. Geol. Survey, vol. II, 1888, p. 407.
Hall and Sardeson: Bull. Geol. Soc. Am., vol. Ill, 1892, p. 338.
tGeol. Wis., vol. I, 1883, p. 121.
JC. W. Hall, Artesian Well-boring in S, E. Minnesota, Bull. Minn.
Acad. Nat. Sciences, vol. Ill, no. i, 1889, p. 138.
Geology of the St, Croix Dalles, — Berkey, 141
Franconia sandstone. The few fossils which occur in lim-
ited horizons are casts from which all traces of the original
shells have been removed. A peculiarly regular distribution
of an iron compound, although the forms outlined by it can-
not be identified, is believed to indicate the position of some
soft-bodied forms, perhaps plants. Copper minerals are not
uncommon, but are always in small quantities and are usually
in the form of carbonates.
The green-sand and shale member, the Upper Dresbach,
is characterized by a bright or dark green to a greenish gray
color. The comparatively large and more evenly rounded
quartz grains in the upper portions of the subdivision, the
abundance of glauconite in the quartzose beds, a shaly and
thin-bedded appearance of exposed portions and a generally
friable nature are typical of these beds. An abundance of
broken but undecomposed shells, an occasional development of
calcareous cementation, cross-bedding in the green-sand bed
and the occurrence of several accessory minerals both orig-
inal and secondary — altogether make the green-sand and shale
member a characteristic one. Occasionally large pebbles of
quartz are found, and in one instance a pebble of quartzyte
was observed. Travertine, apatite crystals of microscopic
size, copper carbonate and iron oxide stains constitute the
principal accessory minerals.
The calcareous and pyritiferous shales, called Lower Dres-
bach, are distinguished from the middle member by differ-
ences which to some extent are the result of the peculiar local
conditions under which they were formed. They occupy the
long, narrow, pre-Cambrian valley between two diabase ridges
now followed by the St. Croix river north of the Dalles. This
valley probably became a secluded bay on the margin of the
Cambrian sea coast in whose shelter myriads of animal forms
found a favorable environment. Among the most pronounced
characters of this member are : — the highly calcareous content
which in many places develops numerous layers of limestone
from one to three inches in thickness throughout a vertical
range of 40 or 50 feet ; an abundance of fossil remains of the
Lingulepis type furnishing a plentiful supply of the carbon-
ates ; and a development in this shale of secondary concretion-
ary pyrite, w^hich furnishes by alteration the sulphates of iron
142 T}i€ Ameficaii Geologist, March, i898
and associated compounds. The argillaceous shale at the
base of the exposed column is greenish gray in color. The
sand present in it occurs in small, irregularly distributed areas,
giving a mottled appearance to the hand specimens. Some
of these sand patches have a regular outline that may indicate
organic association. Linguloid fragments are rare. A mica-
ceous mineral in small scales is accessory.
Chapter II. Hthology of the Igneous Rocks,
Several' descriptions of these rocks have been published*
and the lithologic character of the typical species is so well
known as to require no further attention than the following
brief paragraph as a summary. The rock varies from yellow-
ish green to greenish black in color. It is often porphyritic
and frequently amygdaloidal and pseudo-amygdaloidal . Usu-
ally it is rather finely crystalline and nearly always very much
altered from its original mineral composition. Lustre-mot-
tling is common. Microscopic examination reveals the con-
nection between this lustre mottling and the ophitic structure
represented by the intergrowth of augite and plagioclase. Be-
sides these two minerals, magnetite and pyrite occur as pri-
mary constitutents. The secondary constitutents are quartz,
chlorite, epidote, apatite, calcite and a grayish white granular
substance whose identity is undetermined.
This rock has* been called a melaphyr by Pumpelly, a
melaphyr porphyry by Kloos and Streng, trap by Winchell,
porphyritic trap by Owen, a diabase also by Kloos and Streng,
and an epidote diabase amygdaloid by Pumpelly. Kloos and
Streng call this rock melaphyr porphry, but point out that
olivine and an amorphous matrix are wholly wanting, while
both the essential constitutents and the alteration products
common among diabase are present; and the conclusion is
*Owen: Geol. Survey of Wis., Iowa and Minn., 1852, p. 164.
Kloos: Zeitschrift d. Deutsch. Geol. Gesells., 1871, p. 417. Trans.
by Winchell: loth Ann. Rept. Minn. Geol. and Nat. Hist. Survey.
1881. p. 175.
Kloos and Streng: Neues Jahrbuch fur Min. Geol. und Paleont.,
1877. p. 31. Trans, by Winchell: nth Ann. Rept. Minn. Geol. and
Nat. Hist. Survey, 1882, p. 30.
Kloos: Zeitschrift d. Gesells, fiir Erdkunde zu Berlin, Bd. XII.
1877. Trans, by Winchell: 19th Ann. Rept. Minn. Geol. and Nat. Hist.
Survey, 1890, p. 81.
Chamberlin (Strong): Geol. Wis., vol III, 1880, pp. 365-428.
Geology of the St, Croix Dalles. — Berkey, 143
reached that the rock could with equal correctness be called
a **diabase."
Local variations of the diabase. Although there is a
general similarity in the different outcrops over the whole
area, it frequently happens that very unlike varieties are
formed within a few feet in the same exposure. In many cases
also this difference is not reducible to any known law of posi-
tion. Porphyritic phases occur immediately adjacent to com-
pact and uniform finely crystalline phases in the same bed
and at the same level. This can be said also of many exam-
ples of the amygdaloid and pseudo-amygdaloid. In general,
however, the porphyritic varieties are most prominent in the
upper flows,* while the ophitic character is best seen in the
lower flows. These extremes of variation are noted below.
Lustre-mottled Diabase, This variety forms the bases of
nearly all of the descriptions of the rocks of this locality here-
tofore published. It is the commonest phase of the compact
uniformly crystalline rock. Its greatest development is in
the vicinity of the Dalles, although not confined to that out-
crop. On weathered surfaces it is pitted and brown-colored
from the development of secondary products. On fresh frac-
tures the rock is greenish-black and exhibits numerous spots
over the surface which reflect light from a single cleavage
plane. These spots are augite areas, and imbedded in them
are many feldspar crystals, the two minerals producing a typi-
cal ophitic structure. Other minerals are magnetite and sec-
ondary chlorite, epidote, quartz, and kaolin. Not even in the
freshest sections has there been found a grain of olivine or a
fragment of original glassy matter.
Porphyritic Diabase, At many localities the diabase
shows a marked porphyritic development. The phenocrysts
are of plagioclase feldspar near labradorite in extinction, from
gray to brick red in color, and in size reaching a length of two
or three inches. The most persistent and extensive occur-
rences of the porphyritic diabase are in the series of outcrops
in sections 13, 24 and 25, T. 34 N., R. 19 W., in the southern
portion of Taylor's Falls village along lower Mill street, and
in several localities on the Wisconsin side of the river. It is
always limited in extent. A specimen collected in S. E. } S.
♦Owen: Geological Survey of Wis., Iowa and Minn., 1852, p. 164.
144 The American Geologist. . March, i888
E. \ Sec. I, T. 33 N., R. 19 W., exhibited the porphyritic
phase developed to an unusual degree. The phenocrysts con-
stitute nearly one-half the total bulk of the rock. On weath-
ered surfaces these feldspars are much altered, the resultant
products being chiefly kaolin, quartz, chlorite and epidote.
No constant structural relation seems. to obtain, although the
higher and later flows exhibit a greater tendency to the por-
phyritic development than do others.
Amygdaloidal Diabase, The amygdaloidal zones are
not well developed in this area. Excessive alterations in the
upper portions of the several flows has apparently destroyed
any amygdaloidal structures which may have been present.
Pumpelly and Irving have noted in the rocks of the Kewee-
naw series* a similar condition. In a few cases, however,
the true amygdaloidal character is beyond question, and many
boulders of the conglomerate are also true amygdaloids. The
minerals filling the amygdules are chiefly quartz, chlorite and
epidote.
The pseudo-amygdaloid f is the most extensive alteration
development in these rocks. Chlorite is the first and most
common product, while quartz, epidote, calcite and feldspar
are abundant in varying quantities.
Schistose Structure in the Diabase^ Locally and notabh'
within the village of Taylor's Falls occur limited areas of a
grayish blue tough rock which exhibits schistose structure.
The rock is confined to the separation zones between the
flows, and in one instance it is in contact with an enclosed
fragmental bed. A specimen taken from above the boat
landing at Taylor's Falls, at the contact between the pot-hole
bench and the base of the overlying flow exhibits crumpling
to a limited extent.
Flowage. In places a wavy bandinj^ parallel to the
general trend of the flow is readily observed. Locally this
banding is evident in the completely altered phases of the
rock, while at other places the structure is more conspicuous
in the fresher and more finely crystalline diabase. This struc-
♦Geology of Wisconsin, vol. Ill, 1880, p. 32.
U. S. Geol. Survey, Monograph V, 1884, p. 136.
t Pumpelly: Metasomatic Development of the Copper Bearing
Rocks of Lake Superior. Proc. Am. Acad. Arts and Sciences, vol.
XIII, 1878, p. 268.
Geology of the St. Croix Dalles, — Berkey. 145
ture seems to be due to flowage. The microscope adds
nothing to the distinctness of these bands. They are the only
traces of flowage structure to be found in this rock with the
exception of that clearly shown in certain grains of the vol-
canic tuff.
The ophitic texture so abundantly developed, the mineral
constitution of these rocks and their holocrystalline condition
are characters belonging to a "diabase."
The porphyritic, ophitic and other structures developed
in the rock necessitate some qualifying terms. But the fact
that all these varieties are only local phases of one parent rock,
whose definition may well be broad enough for uny or all of
them, leads to the conclusion that this igneous rock belonging
to the St. Croix Dalles area is most properly designated a
"diabase." The terms "porphyritic diabase," "ophitic dia-
base" and "amygdaloidal diabase" are explanatory of its local
variations.
Volcanic Breccias. In the immediate vicinity of the upper
Dalles on both sides of the St. Croix river loose pieces of
breccia were found. Subsequently this breccia was found in
place just above the public school building in Taylor's Falls.
The fragmental nature of the rock is not readily apparent, for
the rock in place is as hard and compact as other portions
of the outcrop. But on closer inspection it is seen that the
fragments 9f diabase are angular, irregular and of all sizes,
and lie imbedded in a matrix of finely crystalline secondary
minerals, chiefly epidote and quartz. It occurs in one of the
division zones between two flows. The occurrence of a
breccia was not noted until after a division plane between
two flows had been determined upon at this point entirely
upon other characters. Later the discovery of an ash at the
points previously determined upon as divisions between flows
came as a very welcome proof of the accuracy of other ob-
servations.
A breccia results at the contact of two lava flows when-
ever the earlier one presents a surface sufficiently craggy and
vescicular for crushing into a broken mass; or whenever the
later flow supports at its front a particularly abundant crop of
cooled surface-cakes and cindery debris, which are continu-
ally rolled beneath the advancing stream.
146 The American Geologist. March. i89s
Associated with the breccia is a volcanic tuflf. Together
these fragmental rocks are proof of the existence of a series of
successive lava flows in this geographic division of the Kewee-
nawan of the Lake Superior basin.
The Volcanic Tuff, A fragmental rock of varying degrees
of coarseness has been found in place between several of the
flows in the village of Taylor's Falls. Near the intersection of
Government and West streets occurs the most extensive de-
velopment of this type of rock. Together with the breccia
which accompanies it there is a total thickness of about twen-
ty feet at this one point. No differences from the ordinary
diabase are readily noticed at a little distance, for the same
hardness and colors and surface contours prevail in this as in
other portions of the outcrop. At no other place, however,
is the fragmental nature of beds corresponding to this so
easily recognized. It is in so small amount between most of
the flows as to readily escape observation until a knowledge
of the rock structure of the district obtained from other data
is made use of in scrutinizing the most favorable points. Upon
closer inspection the clastic character cannot escape notice.
The individual particles vary in size from mere dust to the
size of an ordinary sand grain, and in the amount of abrasion
to which they have been subjected from roughly angular to
beautifully rounded grains. The upper portion pf the bed
is stratified and the banding due to water sorting is appar-
ent in many specimens. By the aid of the microscope it is
observed that these individual grains are now altered to
quartz, epidote, chlorite, actinolite and similar secondary pro-
ducts in varying degrees. Many grains have therefore en-
tirely lost their original characters, but in most cases it is
probable that the original form of the grain is fairly well pre-
served. Many grains show all the characters of a fine-
grained diabase. These were fragments broken from adjacent
rocks. Others show flowage and devitrification indicating
a more glassy nature. While still others retain nothing of
their original character and seem to have invited rapid and
complete alteration to the obliteration of everything except
external form. These are now most commonly represented
by quartz grains penetrated by actinolite needles, or by epi-
dote. or a mixture of epidote and quartz, or by epidote and
Pun Sill.
^m
m
I:-
Geology of the St. Croix Dalles. — Berkey. 147
quartz and chlorite. The finer material of the tuff is at the
same time the more angular. It is altered chiefly to epidote
and quartz. Large, well rounded grains are in relatively
small amount.
This is one of the few localities noted in the geological
literature of the Lake Superior district where a well defined
tuff derived from volvanic ash occurs. References made to
similar accumulations on Michipicotin island by Selwyn,* and
at Duluth by Winchell and Grantt are the only descriptions
with which the author is acquainted.
Alteration Processes and Products, Quartz, epidote, chlorite,
calcite, orthoclase, hematite, magnetite, hornblende, actino-
lite and copper are the usual secondary minerals of the dia-
base. Quartz, epidote and chlorite are everywhere abund-
ant. Those portions of the rock which have altered largely
to quartz and epidote are the most firm and indestructible
varieties. Many small veins are filled with a fine grained mix-
ture of these two minerals which sometimes carry native cop-
per in considerable amount. Quartz veins and cavities filled,
or partially filled, with quartz are common. Epidote is some-
times well crystallized in these cavities in small individuals.
In many instances secondary orthoclase is associated with
these occurrences. A fibrous quartz vein filling is also found,
probably a pseudomorph after other secondary minerals. The
quartz fillings of amygdules are in certain localities highly col-
ored by ferric oxide distributed throughout the quartz grains
in beautiful dendritic aggregates. Many amygdules are wholly
filled with chlorite. In others epidote is associated with the
chlorite in varying proportions to a complete replacement.
The amount of secondary quartz is also found considerably
more abundant with the epidote than with the chlorite, and
in places it is a substitute for both of these minerals. Chlorite
fills the greater number of the smaller pseudo-amygdules and
is the common secondary product derived from plagioclase
and augite. Calcite occurs in amygdules and is sparingly
distributed through the diabase of several localities. Mag-
netite and hematite are abundant secondary products. The
rock takes on a dense black color due to their presence, while
♦Science, vol. I, 1893, PP- n. 221.
tAnier. Geo!., vol. XVIII, Oct. 1896, pp. 211-213.
148 The American Geologist, March. i8»8
thin sections show that the cleavage and fracture planes of
the primary minerals as well as the interstices between them
are more or less completely filled with these alteration pro-
ducts. No titanic acid is discovered in the rock. The small
plagioclases are the only original constituents whose outline
and original character are even partially preserved where mag-
netite segregation has been most energetic. In the fresher
portions of the diabase the plagioclases are clear and com-
paratively unaltered; in the more advanced stages of altera-
tion, quartz and epidote pseudomorphs preserve, the original
crystal form in considerable perfection. The staining due to
ferric oxide is common to all phases of these rocks. Horn-
blende is not abundant. One of its most interesting develop-
ments is a fibrqus vein-hlHng which in turn is being replaced
by secondary quartz. There occurs sparingly distributed in
certain altered phases of the diabase, and quite abundantly
developed in the accompanying fragmental beds, a fibrous
secondary mineral identified as actinolite. It occurs most
commonly piercing the quartz grains which are abundant in
these altered phases.
Summary, As a summary of the observations made on
the alteration tendencies of these rocks, the following state-
ments can be made:
First, — There is an alteration towards quartz and epidote
leading to a most indestructible rock. The upper zone of each
flow is more subject to this alteration than any other portion,
although the inclination to this change is not confined to any
particular part of the flow. The rock always assumes a yel-
lowish green color in this stage.
SecoTid. — There is an alteration toward a highly ferrugi-
nous rock in which the usual secondary minerals are pres-
ent, but in which secondary hematite and magnetite are ac-
cumulated in great abundance along all boundaries and frac-
tures of the original minerals. The color of the rock be-
comes then a dense black.
Third, — There is an alteration toward a kaolinized earthy
mass in which the only minerals determinable are quartz and
kaolin and an iron oxide with more rarely copper carbonate
stains. This phase is almost wholly confined to the basal con-
glomerates in which the conditions for disintegration and the
Geology oftJie St, Croix Dalles, — Berkey, 149
removal of soluble substances are especially favorable. An
intermediate stage common in varying degrees to each line
of alteration is that of chloritization. There seems to be no
variety of this rock wholly free from this last named product.
Chapter III. Minerals,
Gold, An assay of the pyritiferous shales at Taylor's
Falls shows traces of gold, but beyond this no evidence of the
precious metal was found in any of the rocks of this area.
Copper. Native copper occurs in small quantity in the
epidotic portions of the diabase flows. A thin section cut
from a rock specimen taken from an epidote vein, Sec. i, T.
34 N., R. 19 W., shows numerous grains of copper scattered
throughout the slide. The matrix is a finely crystalline in-
termixture of secondary quartz and epidote. Copper is also
found occasionally in the glacial drift.
Pyrite, This mineral occurs sparingly in the igneous
rocks. It is most readily obtained in the railroad cut at Tay-
lor's Falls and at a similar cut on the "Soo" road, two miles
north of Dresser Junction. Pyrite occurs in great abund-
ance, however, in the Lower Dresbach shales. The finest
specimens were obtained in the small ravine below the card-
ing mill in Taylor's Falls. In portions of the shale at this
place small rounded concretions of secondary pyrite the size
of a pin head constitute fully one-fourth of the bulk of the
rock. Forms of brachiopod shells are also preserved by the
pyrite. The plentiful yellow and white efflorescences formed
on the exposed surfaces of these shales are no doubt chiefly
the result of decomposition of the pyrite.
Quartz. This mineral is crystallized sparingly in the
larger cavities of the diabase. It occurs as a coarsely crystal-
line filling in amygdules and in veins. In the form of more
or less rounded grains it constitutes the bulk of the sedimen-
tary strata of the area. A cryptocrystalline variety is noted in
certain of the sections of volcanic ash.
Magnetite. Primary and secondary magnetite is abundant
in most varieties of the igneous rocks of the area. As a pri-
mary constituent it occurs in grains of more or less regular
outline imbedded in the diabase. As a secondary constituent
it occurs in irregular aggregates and branching spear-like
1 50 The American Geologist, March, i898
forms and dense masses in badly decayed portions of the rock
from certain localities. In some instances this secondary
magnetite constitutes almost a perfect outline of an original
mineral constituent, and usually accumulates along the mar-
gins or in the crevices of such decaying minerals.
Hematite. Ferric oxide is abundant as a staining substance
in the sandstones and conglomerates. In many places the
veining produced by the accumulation of this oxide in the
sandstones produces branching figures of surprising com-
plexity. In other places accumulations are more abundant
and exhibit all the characters of hematite ore. Hematite is
also formed as a fissure filling in the diabase. And the quartz
of these rocks is highly colored by especially beautiful den-
dritic crystallizations. The rusty brown color noticeable on
decaying surfaces of the mottled diabase is ferric oxide. The
calcareous shales are so highly charged with it as to present a
brown red color on a fresh fracture. Rut in spite of its
abundance and wide distribution, there is no considerable
segregation at any single point.
Calcite. Within cavities in the conglomerate at St. Croix
Falls there are developed nun\erous well-formed calcite crys-
tals. They are chiefly of the nail head variety, although other
forms also occur. A similar crystallization of calcium carbon-
ate occurs in the conglomerate at Taylor's Falls, but the crys-
tals are not so well-formed nor so abundant as at the other
locality. Crystalline calcite occurs sparingly in the diabase.
Travertine. This variety is deposited in very compact
and well banded masses in the larger cavities and caverns of
the Dresbach formation along the river bluffs.
Dolomite. Small crystals of dolomite associated with
calcite are abundant in the conglomerate at Taylor's Fjills.
Certain compact portions of the exposure exhibit a crystalline
phase in which the chief constituent is dolomitic in composi-
tion.
Malachite. Malachite is seen in many places near a contact
of the sandstone and diabase as a green, earthy coating upon
quartz grains or in cavities among the boulders of conglom-
eratic phases of the rock. It is especially noticeable at the
Taylor's Falls conglomerate exposure. Oxide of iron con-
taining copper and coated with malachite was secured from
Sec. I, T. 33 N., R. 19 W., from the sandstone.
Geology of the St. Croix Dalles, — Berkey. 151
Aziirite. The blue carbonate has been noted in association
with malachite and dolomite. Other copper minerals have
been reported from this locality but have not been encountered
during this investigation, and visits to the sites of old mines
have not usually shown any traces of the minerals for which
they were worked.
Orthoclase. Secondary feldspar is rather well developed
in cavities of the rocks where there has been considerable
alteration. It is a flesh red mineral altering readily to quartz
and frequently exhibiting crystal outlines. It is associated
chiefly with quartz and epidote.
iMbradorite . Both original and secondary feldspars arc
])resent in the diabase rocks. The original representatives of
this group all belong to the plagioclase division near *1abra-
dorite.'' There is no essential difference between the large
phenocrysts of the porphyritic phases and tlife smaller indi-
viduals of the second generation in the ground mass. All
the feldspars show more or less alteration to kaolin, chlorite;
epidote and quartz, and in many cases nothing remains but
the outlines of these pseudomorphs to indicate the character
and position of the original constituent.
Aiigite. This mineral is prominent in the fresh eruptive
rock. It is especially well-developed in the lustre-mottled
variety, where crystals of this mineral serve as the hosts for
numerous plagioclases giving a typical ophitic structure.
Hornblende. Hornblende is not common. It occurs how-
ever, as a secondary mineral in a few sections. The speci-
mens already noted indicating a replacement of fibrous horn-
blende by quartz are the most interesting.
Actinolite. In many sections cut from the more highly
altered rocks, and especially from those carrying a consider-
able amount of secondary quartz, is a fine fibrous mineral
which is believed to be actinolite. Its finej hair-like fibers,
usually crystallized in radiating bundles, penetrate the quartz
grains in great profusion. This mineral has been noted chiefly
in the bed of volcanic tuff and in the brick-red blotches occur-
ring in the diabase at the elbow of the river on the Wisconsin
side. This is supposed to be the mineral referred to by Kloos
and Streng as apatite needles.
yinscoviit\ A light colored mica identified as muscovite
152 The American Geologist March, isw
occurs in the Franconia sandstone and in the lowest bed of
the Dresbach shales. It appears as minute glistening scales
abundantly among the other mineral constituents of this for-
mation.
Biotite, This mica is developed occasionally as a secon-
dary product in the alteration of the diabase.
Epidote, Next to chlorite the most abundant secondary
mineral is epidote. It is the yellowish green variety and gives
those portions of the rock in which it is a prominent constitu-
ent a characteristic yellowish green color. Many amygdules
are filled with this mineral, and in some them it is quite per-
fectly crystallized. Quartz and epidote are contemporan-
eously developed. Needles of epidote penetrating the clear
grains of quartz are frequently seen. Epidote is apparently of
later development than chlorite, although all the secondary
products are at times simultaneously produced.
Olivine. No olivine has yet been observed in any portion
of this rock. Certain apparently pseudomorphous develop-
ments of secondary products may possibly indicate the orig-
inal presence of this mineral. There is, in the first place, a
segregation of secondary magnetite forming the outline of a
well-defined crystal form closely resembling the usual occur-
rence of olivine. There is also a canal-like structure some-
times present in the areas of chlorite which may indicate that
it is a pseudomorph after the usual serpentinous alteration
product from olivine.
Chlorite. The mineral identified as chlorite is an amor-
phous or granular or sometimes fibrous substance which has
d uniformly deep green or bluish color. It has a hardness of
2 ; it occurs in great abundance in all phases of the diabase as
a secondary product, replacing portions of the original min-
erals and filling cavities and interstices between them. The
universal presence of this substance gives all varieties of the
rock a greenish cast. It seems to be the earliest secondary
mineral. In one of the sections a decomposing feldspar crys-
tal is seen changed first to chlorite at a considerable distance
from the lines of fracture, while after it in a narrow zone fol-
lowing the original fracture are developed quartz and epidote
in small amounts. Those localities in which the rocks are
most free from chlorite display the most highly epidotic zones.
Geology of the St. Croix Dalles. — Berkey, 153
Glauconite, An earthy granular bright green mineral
occurs abundantly in the Dresbach formations. It is recog-
nized as glauconite and is the same mineral that is so abund-
ant in the St. Lawrence formation of many localities.*
Kaolin. This mineral is present in small quantity as an
accompaniment of the process of alteration. A few speci-
mens, however, have been obtained in which kaolin is the chief
resultant of decay. This particular line of alteration seems
to have been of limited extent, as suggested in a previous
paragraph, and is most noticeable in the conglomerates of the
Dresbach formation.
Apatite. Phosphoric acid is abundant in the lower sedi-
mentary strata of this area. The Lingulepis shells give strong
tests for this compound and in the green-sand bed number-
less microscopic apatite crystals have been developed as a sec-
ondary mineral constituent. The phosphoric acid reaction is
readily obtained from the Obolella (green-sand) bed and also
from the Lingulepis (calcareous) shale. Although these mic-
roscopic crystals are very perfectly and abundantly developed,
no individuals of larger size have yet been observed.
Sulphates. The efflorescence formed on the exposed
pyritiferous Dresbach shales at the carding mill, Taylor's
Falls, has proven quite complex in its composition. The re-
sults of an analysis made by Mr. H. A. Webber, a student in
the University of Minnesota, is as follows:
Si O, 12.946 per cent.
Fe, O, 22.828
A1,0. ,4.141
K,0 1.844
' Nag 4.659 "
CaO 2.210 "
SOg 32.500
H,0 17.840 "
Organic matter traces
Total 98.968 per cent.
This analysis is similar in complexity and general range to
voltaite (Dana, p. 927), but it is not identical with any known
mineral. It is apparently a mixed substance. The most puz-
♦Magnesian Series of the Northwestern States. Bull. Geol. Soc. of
America, vol. V, 1895, p. 172.
1 54 The American Geologist, March, isds
zling parts of the analysis are: Si O2 — 12.946 per cent and
Ha O — 17.848 per cent. Silica is high and apparently out of
place, while H2 O is low for the sulphates. This substance
forms abundantly on the exposed shales as greenish yellow
rather compact and somewhat globular masses out of the
water which is constantly dripping from the lower beds.
Whenever these masses become detached or are subjected to
evaporation the efflorescence is noticeably different in charac-
ter. It is white and porous or frost-Hke, and presents the
usual appearance of the sulphates formed upon exposed mar-
casite nodules. A bitter taste to the shales at the contact op-
posite St. Croix Falls was noted by the Wisconsin geologists*
and ascribed to the formation of sulphates. A complete chem-
ical analysis of the white substance has not been made.
Explanation of Plate XII.
Fig. I. Section of Volcanic Tuff,
The figure is from a microphotograph of a section of the volcanic
tuff from Taylor's Falls. Diabasic characters are shown by the darker
grains in the figure, and one fragment especially at the right side ex-
hibits a coarser texture than is usual. Several grains near the lower
margin of the field are devitrified glasses. In grains of this character
flowage is sometimes prominent. The light colored fragments through-
out the field are now chiefly quartz. But these almost all show their
secondary character by the penetration of actinolite needles which pro-
ject in beautiful clusters. Finer fragments of a more angular outline
lie between the larger grains.
Fig. 2. The St. Lawrence Shales.
The figure is reproduced from a photograph of a hand specimen
obtained at Osceola Falls. The darker portions of the figure represent
quartz sand; the light wavy threads and bands are greenish clay shale.
A study of this specimen and a comparison with others of different
localities, especially those representing phases of the dolomites, and
also a series of chemical tests, completed since writing the paragraph re-
ferring to this figure in the text, altogether have led me to ascribe not
a little of the irregularity of banding in the shales to the removal of sol-
uble constituents subsequent to their original deposition. The St. Law-
rence formation in some localities is a dolomite. A theory of the origin
of dolomites as maintained by Hall and Sardeson in their paper on
"The Magnesian Series of the Northwestern States" (loc. cit.), argues
the removal of calcium carbonate from rocks at a greater rate than
magnesian carbonate. The result is a limestone growine by continuous
♦Geology of Wisconsin, vol. Ill, 1880, p. 418.
Concentration by Weathering,— Kimball, 155
reduction into a more arenaceous or argillaceous and a more highly
dolomitic rock, and at the same time one which is more irregular in its
bedding lines. In the true dolomites the shale and* sand constituents
have been evidently of small amount But in strata where these two
constituents are prominent, the process would doubtless result in a dis-
tortion of the sedimentary banding similar to that of the figure. This
may become, as in this case, the most noticeable distinguishing feature
of the rock.
RESIDUAL CONCENTRATION BY WEATHERING
AS A MODE OF GENESIS OF IRON ORES.
By James P. Kimball, New York.
In descriptions of important secondary deposits of sub-
specular iron ores on the south coast of Cuba in the year 1884,*
mention was made of other numerous interesting but com-
mercially unimportant, ferriferous products different in type
and likewise secondary. These were characterized as con-
centrations of ferric and magnetic oxides upon outlying sur-
faces of dioritic dykes, and also developed to some extent
within a great mantle or overflow of diorite. Involved within
the same overflow are enormous isolated masses of elevated
and disrupted coralline rock, some of which in stated circum-
stances have completely given way to replacement by hematite
and martite. Further illustrations of both types of deposits
have also been given by the present writer in a recent number
of The American GeologistI with reference to associated oc-
currences on islands of British Columbia. Incidental mention
was made in the same place to similar occurrences in cul-
minating regions of the Cascade range in Washington.
Numberless dykes in the foothills of the Sierra Maestra in
Cuba, alike in age and original character, have undergone no
such superficial alteration as above referred to, or, at least,
preserve no evidence of the kind. That such superficial con-
centrations of oxides of iron are not due to original magmatic
lifferentiation, on the Soret principle, is clear from the fact
that eroded tops of intrusive masses and dykes are apt to pre-
*Am. Jour. Sci., XXVIII, 416; Trans. Am. Inst. Min. Eng.,
XIII, 613.
tVid. Vol. XX, July, 1897.
156 The American Geologist. March, 18O8
sent the greater display of ferriferous products. Their develop-
ment is limited Jo exposed surfaces. When otherwise than a
mere speculum, the oxide is characterized by prismatic cleav-
age. Both detritus and float are then particularly rich. Dykes
in which no prismatic cleavage is pronounced exhibit as a rule
no more than a coating or specular surface of ferric oxide.
This holds true with regard to the more expansive intrusions.
When presented in outliers distinct from the overflow some
of these are of imposing aspect, bearing semblance to fine
bodies of ore. The sharp ringing sound from a blow with
the hammer serves to distinguish such masses, as well as any
form of their detritus, including even an excellent type of ore
of like origin, abundantly afforded in places as float.
From the fact that the iron ores classified in my original
descriptions as concentrations are essentially superficial, it was
argued on general grounds that little or no economic value
could attach to them. So deceptive in appearance, however,
were some of these occurrences in an unbroken state in the
year 1884 that several of them had been located by denounce-
ment, and the critical attention of geologists and capitalists
confidently invited with a view to development as ore de-
posits.
Reference .is here made to a subordinate and worthless
type of ferriferous developments rather than to the character-
istic class for which the region is renowned, because it serves
the present purpose of comparison with somewhat analogous
occurrences which have proved even more deceptive in ap-
pearance. Both occurrences are, nevertheless, significant of
one mode of genesis or differentiation of iron ores, namely,
by residual concentration of iron oxides as a result of weath-
ering action.
The second instance referred to is a remarkable differential
development of ferric and magnetic oxides from an amorph-
ous basic aggregate in the state of Washington on Cle Elum
river, one of the tributaries of the Yakima. This fine moun-
tain stream, which expands into two lakes of the same name,
distinguished as Upper and Lower, penetrates the more
mountainous parts of its course in a deep gorge several miles
long. Mountains on either side rise to elevations of several
thousand feet. The Cascade range on the west presents tow-
Concentration by Weathering, — KimbalL 157
ering escarpments rising from the river canon. On the op-
posite side foothills of the same range fall off toward the val-
ley of the Columbia.
At the time of my visit to the region, in the month of Sep-
tember, 1890, some eighteen contiguous mining claims had been
located, together forming a loop, and covering the bottom lands
and both mountain sides. The whole stretch of locations
compassed what was concluded to be remnants of a faulted
boss or dome of a stratiform ferriferous series. By subsidence
of the arch the medial portion overspreads the narrow valley
])ottom wherever not obliterated by erosion. Uneroded parts
in minor undulations traverse low hillocks. Hence gentle
quaquaversal dips and small saucer-like basins. Steep re-
treating dips of the same series enter the mountains on either
side beyond the planes of fault at different elevations, namely,
«it 4,675 feet on the east and about 1,000 feet lower on the
opposite side. From the greater part of the area of the bot-
tom lands the ferriferous beds have been eroded. Even on the
circling line of mineral locations corresponding to an outer
margin of the subsided arch their preservation is only partial.
The present river channel follows the line of the western fault.
Affected as they are by unequal erosion and somewhat
variable in section, the beds in question present a total thick-
ness of from six to eighteen feet. They constitute three divis-
ions of an amorphous aggregate. This series is underlain b\
crystalline pyroxene and surmounted by micaceous sandstone
passing into conglomerate, both conformable and of meta-
niorphic type.
The notable occurrence of iron ore, properly so discrim-
inated, is at the base of the series of ferriferous, or, rather,
ferruginous, beds. In quality and thickness this is far from
uniform. Its development is confined to wet places and ex-
posed ledges.
In circumstances thus favorable to atmospheric oxidation
and percolation of water, magnetite, martite, hematite and
limonite have been exfoliated as an insoluble residuum from
decomposition of the basic aggregate. These mixed products
have a foliated structure. The separate folia serve to dis-
tinguish progressive exfoliation of iron oxide. Thus siliceous
residuums separate lustrous folia of chromiferous magnetite.
158 The American Geologist. March, i89s
and, in the case of more thoroughly weathered material, more
or less hydrated hematite likewise chromiferous. The thick-
ness of the deposit in this particular relation varies from two
to eighteen inches. Just beneath developments of this de-
scription the basal pyroxene is, to the depth of a few inches,
commonly decomposed into a soft chloritic clay.
In places where local topography has been favorable to
weathering action this ferriferous exfoliation graduates up-
ward into an impure sub-specular product, a mixture of ferric
and magnetic oxides characterized by a remarkable prismatic
cleavage which seems wholly incidental to the partial or in-
cipient alteration. Though possessing a low specific gravity
and affording a gjeen streak and powder, this product is of a
dull sub-metallic lustre on all cleavage faces even to the min-
utest mechanical sub-division. Natural surfaces of outliers of
this base material, such as are developed by a sort of potential
cleavage, are commonly veneered with ferric oxide of sub-
metallic lustre.
In extremely favored spots, as on **Magnetic Summit/' so-
called, the peak of Emerson, or East Mt., the same di-
vision at shallow depths is more thoroughly altered into a
dense sub-specular product of high specific gravity. Similar
material likewise unequally developed on a small scale is
sometimes noticed amongst the gleanings at the several ex-
cavations in thd valley. The quantity, however, is commer-
cially insignificant, and the quality of the best indifferent.
At several of the explorations no development of distinctly
ferriferous products is observed, especially in well drained
hillocks. At others specimens of rich iron ore, chiefly from
the base of the series, can be gleaned. On the more northerly
locations, known as the Duke and the Iron Bluff, in the valley
bottom, no development of ore has taken place, the black
lustrous surface of the outliers alone affording semblance to
iron ore. The miscellaneous character of the products sub-
mitted by the explorers for analysis is proof of the indiscrim-
ination with which they had collectively been regarded. The
bulk of the whole material had, indeed, been mistaken for
iron ore, not only by local miners unfamiliar with iron ores,
but also in one instance by a professional observer specially
sent out from London.
Cance7itration by Weathering, — Kimball, \ 59
The third or upper division is characterized by a sub-
nietalHc lustre and by prismatic cleavage — both evidently de-
veloped by weathering. Although apparently of the same
mineral composition as the two lower beds, it is in places
largely made up of pebbly or spherulitic differentiations, the
origin of which is an interesting object of inquiry thus far
unaided by the microscope. Interposed between aphanitic
layers and an overlying siliceous conglomerate, this bed,
macroscopically at least, has the casual appearance of coarse
augitic psammite. Between a clastic origin and a concretion-
ary origin of the spherulitic contents there lies a doubt. These
have become pronounced, if, indeed, they have not actually
been developed, by weathering action, as manifested by partial
or complete replacement of the original material with anhy-
drous oxides of iron. In comparatively ur.altered rock, as
on the Monarch location, the only feature in obvious relation
to such occurrences is a mottled fracture suggestive of unpro-
nounced or incipient concretionary structure. In some parts
of this bed, as on the Boss and Iron Monster locations, an
iron ore of tolerable quality is developed by more or less
complete conversion of the spherulites into ferric oxide.
Isolated and protuberant examples of these products bear
resemblance to terebratuloid forms. The mineral alteration
which they have undergone is of the same kind as that which
has taken place on the surface of exposed ledges and on cleav-
age surfaces. While it is true that, the third bed which, as
the most pronounced in character must be regarded as the
physical type of the thin series, is not without features in
common with a clastic tuff of volcanic origin, the above facts,
taken along with certain negative evidence, point, as I con-
clude, to a metamorphic origin.
Every gradation in tenor of iron oxides from unaltered to
highly metalliferous material is presented by all of the beds —
sometimes within a very narrow compass. Material from all
of the beds exhibits polarity. Fragments from the middle
bed on Iron Mt., where the attitude of the series is nearly ver-
tical, act as powerful loadstones. Even the unaltered greenish
augitic material, charged with minute grains of magnetite, is
not without decided effect on the magnetic needle. The pres-
ence of lime, as shown by analysis, is doubtless an important
agent in the transformation above described. As in most
i6o
The American Geologist.
March, IMi*-
ferriferous developments from serpentine, the richer products
are also shown to be chromiferous.
Numerous commercial analyses of the material above de-
scribed had been made at the instance of the owners. Not-
withstanding a lack of full description of the samples analyzed,
the significance of these incomplete analyses, taken together,
is plain.
Samples collected at six different points by an English
engineer, and by him claimed to represent a seam or belt fif-
teen to twenty feet in thickness, afforded, upon analysis by
Dr. Edward Riley, of London, a mean percentage of iron as
high as 51. no, and of silica as low as 7.410.
That these samples, while perhaps approximately repre-
senting concentrations as above described, failed to represent
anything like the average composition of the whole formation
is sufficiently clear, beyond a doubt, after careful discrimina-
tion.
A series of seventeen partial analyses by Prof. James A.
Dodge, of the University of Minnesota, however, may be
assumed to represent several of the more ferriferous types of
material. Of the number of samples furnished to Prof. Dodge
by interested parties, nine were products ranging from 49 to
63 per cent, in iron. The rest of the analyses, though incom-
plete, indicate clearly enough the character of basic aluminous
silicates. The following are the analyses referred to:
Lm-ations.
Dudley (hematite)
Emerson (centre)
Emerson (top )
Beverly (hematite)
(4i)8 undet.)
Magnet
Stronghold
Nigger baby (limonite)
Clayton (magnetite)
Boyle (hematite) . ."
Nelson
Swak
Haskell
Mack
Cle Klum lake
Iron Yankee
West Gulch (magnetic)
Mother Hubbard (magnetic)
Me-
tallic.
Iron.
63.05
S7.51
55 84
60. q5
56.79
52-31
52.99
49.44
51-39
42.85
22.37
22.71
24.36
15.3^
42.38
40.74
39 29
Alu-
mina.
2.39
2.61
0.84
2.26
4.72
6.01
15.65
12.17
7-95
7.71
6. 19
Silica
Phos-
j) ho-
rns.
11.07
1332
6.07
9-49
14.32
24. 9«
47. OQ
47.40
37-33
20. 8()
trace
0.06
0.05
0.01
0.02
0.03
0.25
o. 18
trace
o. 16
0.03
O. II
O.OQ
0.03
O.OI
o. 15
O.OI
Sul-
phur.
0.04
none
none
t«
(t
*<
0.04
0.02
O.OI
0.02
none
0.05
O.OI
none
ChO&Mn
do
ChO, i.^^
ChO
CaO, Mn
<t
it
CrO
CaO
ChO
Concentraticni by Weathering, — KimbalL l6l
For lack of considerable development of ores of a high
class, the mineral locations here briefly described are of no
economic importance. The false estimation in which they
had been held arose from failure to distinguish between the
several kinds of material selected for analysis with due refer-
ence to their relative quantitative development. As an exam-
ple of one mode of genesis of iron ores, however, the occur-
rences on the Cle Elum are not without significance.
Specimens collected by myself to represent extreme types
of the two kinds of material, the one altered (I) and the other
unaltered(II), both from the Boss location, have been analyzed
by Mr. Cabell Whitehead, Chemist of the Bureau of the Mint
The analyses are as follows:
1 II
Ferric Oxide * 82.56 50.26
Ferrous oxide 1.24 0.69
Alumina 4.08 23.70
Chromic oxide 5.20 Not determined.
Lime 0.28 1.27
Magnesia i.oi 1.02
Manganous oxide 0.30 0.43
Oxide of Nickel 0.68 Not determined.
Silica 3. 10 1 4.40
Water 1.53 Not determined.
99.98
Metallic iron 58.77 35. 16
According to Mr. Whitehead's analysis the comparatively
unaltered product (II) is remarkable for its high, tenor of ferric
oxide in relation to the low percentage of ferrous oxide. The
figures point, of course, to epigenesis of the higher from the
lower oxide in spite of the green streak and powder of this
product.
The occurrences above noted clearly indicate, as it seems
to me, the differentiation of iron oxides from an amorphous
basic aggregate through weathering action on natural sur-
faces by residual concentration incidental to isolation and
waste of earthy residuums. Development of prismatic cleav-
age and exfoliation of the same oxides on cleavage planes,
even to the minutest sub-division, are incidental phenomena.
That the oxidation of ferrous oxide in unisilicates to the higher
oxide through meteoric influences in so dense an aggregate
is thus limited, except in wet places, is not difficult to explain.
Hie fixation of ferric oxide is probably not disconnected from
«
i62 The American Geologist, March, isp**
initial replacement of calcic carbonate through ferrous car-
bonate — both products of the splitting up of basic silicates,
the original components of which were not in stochiometric
proportions. The last inference may be drawn from the
amorphous condition of the ferriferous beds as well as from
analyses. The only evidence of any other kind of differentia-
tion is occasional segregation of calcite.
In the present example the transformation is obvious.
Equally obvious, of course, it would not be had its progress
involved the whole formation, or even uniformly a single
division. In the bearing of this example on differentiation
and concentration of ferriferous products from basic and
somewhat magnetic aggregates, it is uncommonly instructive.
Similar differentiation from eruptive basic magmas in Cuba
previously instanced as a product likewise of weathering ac-
tion, affords a further illustration of a common mode of
genesis of iron ores from basic material.
It is natural to infer that superficial and even interstitial
concentration of stable magnetite incidental to hydro-chemical
rearrangement and leaching of basic rock, of which this
mineral is a component, may be largely, if not wholly, res-
idual. Apart from such a mode of occurrence as distinguished
by special paragenesis, its presence in concrete form in non-
magnetic rocks, in numerous cases instanced by the writer in
previous pages of The American Geologist, is through
stochiometrical transformation of ferric hydrate at ordinary
temperatures. Transformation of this kind by gradation
proves to be among the more common microscopic manifesta-
tions of epigenesis of basic crystallines, attended with loss of
basicity. Diminished basicity seems invariably, so far as I
have observed, and as I have instanced in numerous descrip-
tions, to characterize and differentiate regional parts of rocks
marginal to concentrations of anhydrous iron oxides, and as
particularly witnessed in development of secondary siliceous,
or residual products like chlorite, epidote, garnet and jaspers
from gabbro, diorite, diabase, etc. Superficial, unlike inter-
stitial, concentrations in basic rocks seldom, if ever, appear of
economic importance. Far more important products are
those derived from essentially calcareous paragenesis when
iron salts, locally generated and entering into passing solu-
Concentration by Weathering. — Kimball, 163
tions, have yielded to the stronger base. While chemical
action is here only in a limited sense superficial, progression
is from without inward. Replacement of calcareous material,
like limestones, marbles and coralline rock, with ferrous salts,
is then effected, whence spontaneous development of ferric
products on receding surfaces. Among the several examples
of advanced or advancing replacement of this kind which 1
have had opportunities to study, are several where it is com-
plete, and others again where it is only partial. In the latter
class the mode of occurrence is always the more obvious.
In every case the degree of purity of the ultimate ferriferous
products depends, of course, on relative degree of siliceous
admixtures in the parent material.
The common association of the higher ferric oxides in
more or less concrete form, as on Texada and Vancouver isl-
ands, with epidotic products from epigenesis of hornblendic
aggregates, in which products the iron base is present as ferric
oxide, points to ultimate or residual concentration of the same
oxide from the secondary product by progressive epigenesis,
and perhaps also in some ratio of original distribution of fer-
rous oxide in the parent material. Beyond some ratio limit
of this kind still further development of ferriferous products
points again to extraneous or diffuse sources of ferrous solu-
tions, and likewise to circulation of alkaline carbonates
evolved from silicates.
The phenomena above described, in common with others
of the same class previously illustrated,* notwithstanding wide-
ly varying paragenesis and environment, are, in a word, all
incidental to fixation of stable iron oxides from penetrating
solutions of ferrous salts by progressive oxidation, following
as a final result from primary double decomposition with
alkaline carbonates by processes more or less regenerative.
In the memoir first cited below the cyclus referred to has
been fully discussed from a chemical point of view.
*Am. Jour. Sci., XLII, 1891, 231; XXVIII, 1884, 416^
Am. Geologist, VIII, 1891, 352; XIX, July, 1897.
Trans. Am. Inst. Min. Eng., XIII, iSSi^, 613.
HL
164 The American Geologist. March, i8»8
OSCILLATIONS OF LEVELOFTHE PACIFIC COAST
OF THE UNITED STATES.
By William P. Blake, Tucson, Arizona.
The oscillations of level of the California coast have of
late years been ably discussed by Lawson,* Ransome,t David-
son, Le Conte and others, and recently in this journal by
Fairbanks.t
In these discussions the significance of the Ocoya Creek
formation does not appear to have received the recognition
it merits.
Lying at the western base of the Sierra Nevada in undis-
turbed horizontal strata of marine origin of wide extent and
at an altitude of from 700 to 1,500 feet above the sea, this
formation records an epirogenic movement in strong contrast
with the orogenic uplifts to which the initial topography of
the Coast ranges is due. The beds consist, generally, of sandy
sediments accumulated during a period of subsidence, and
in comparatively shallow water. But they contain evidences
of considerable volcanic activity, such as beds of pumice and
even fragments of charcoal showing the prevalence of forest
fires, due, probably, to incursion of lava in the ancient forests
of the Sierra.
The marine remains consist of numerous genera and
species of Mullusca piled together in a littoral accumulation at
the base of the hills, and now some 700 feet above tide-water,
while from the tops of the- hills which rise some hundreds of
feet higher the teeth of sharks and bones of cetaceans are
strewn upon the mesa as upon the ocean floor. The evidence
of recent epirogenic uplift appears to be conclusive.
The exact altitudes of the ancient shell beds and of the tops
of the hills need to be more carefully determined than was
possible at the date of the reconnoissance in 1853, but it would
appear from those observations that the upper beds are now at
least 1,500 feet above tide. It is also desirable to have a re-
*The Post-Pliocene Diastrophism of the Coast of Southern Cali-
fornia, by Andrew C. Lawson, Univ. of Cal. Bull, of the Dept. of
Geology, I, No. 4, Dec, 1893. Also The Geomorphogeny of the Coast
of Southern California, Ibid, No. 8, Nov. 1894.
tThe Great Valley of California — A Criticism of the Theory of
Isostasy, by F. Leslie Ransome, Ibid, No. 14, May. 1896.
^Oscillation of the Coast of California during the Pliocene and Pleis-
tocene, by Harold W. Fairbanks, Oct. 1897, No. 4, p. 213.
Valley Moraines and Drumlitis, — Upliam. 165
vision of the question of the age of the formation, considered
by Conrad to be Miocene. This opinion was formed upon the
genera and species represented by the drawings made by me
upon the spot from the casts of the fossils.* In many cases
the specific character of some of ^ the common genera,
Cardium, Area, Selen, Doseniay Venus, and Cytherea,
could not be made out. The remains of cetaceans were found
by me at a second visit many years after the publication of
the results of the collection made in 1853. ^^^^ whole aspect
of the hills is more modern and recent than of any well- recog-
nized Miocene of the western coast. But whether Miocene or
Pliocene the formation records a comparatively recent uplift
of 1,500 feet or more, after a subsidence of an equal amount
and sufficient to give the Pacific ocean free access to the base
of the Sierra Nevada and to make a chain of islands of the
Coast mountains.
[European and American Glacial Qeology Compared. 11.]
VALLEY MORAINES AND DRUMLINS IN THE
ENGLISH LAKE DISTRICT.
By Warren Uphau, St. Paul, Minn.
From Llanberis we returned June 14th (1897) to Carnar-
von, and the next day to Chester, continuing thence north-
east and east through Manchester and Huddersfield to Leeds.
This railway passes in a tunnel about two miles long through
the axial part of the south to north highland belt of the Pen-
nine Chain, which is continuous along a distance of nearly 150
miles through northern England.
Under the guidance of Prof. Percy F. Kendall and Mr.
Arthur R. Dwerryhouse, of the Yorkshire College, Leeds, I
much enjoyed an excursion north nearly twenty miles to Har-
rogate and the Nidd valley at Knaresborough and westward,
♦A full description of the Ocoya Creek beds and of the fossils may
he found in my "Report of a Geological Reconnoissance in California."
4 to. 1853, pp. 164-173. Also, in Vol. V, "Pacific Railroad Surveys."
In this connection it is well to note a strange jumble of errors in a
foot note to Mr. Lawson's paper on "The Post-Pliocene Diastrophism
of the Coast of Southern California." Bull. Univ. Cal. Dept. Geol. p.
119. No Miocene fossils, or others, were found by me at San Diego,
or were handed to me there. The basis of the reference is probably an
echo of the old attempt of Prof. Gabb and the California Survey to
discredit my discovery of the Tejon Eocene.
i(>6 The American Geologist March. i89h
going from an unglaciated to a glaciated area, observing mar-
ginal till and kame deposits, and noting glacial changes in the
course of the river Nidd.
Leaving Leeds early in the morning of June 17th, our
route was west and qorth through Hellifield and Kirkby
Stephen to Appleby, there delaying about three hours for con-
nection with a train to Penrith and Keswick. The delay per-
mitted me to take a short excursion to the east and north,
seeing some of the drumlins, 40 to 60 feet high, along this part
of the river Eden, in a district well described, as to its glacial
geology, by Mr. J. G. Goodchild.* Looking northward from
Appleby, we saw snow of the previous day's storm on the top
of Cross Fell, the culminating point of the Pennine Chain,
2,930 feet above the sea; and looking west, beyond a finely cul-
tivated lowland, we saw the group of sharp-peaked mountains
which occupy the English Lake District, 20 to 40*miles distant.
In Keswick, a town of 4,000 people, near the foot of lake
Derwentwater, in the midst of the Lake District (also known
as Lakeland), surrounded on all sides by beautiful and grand
mountains, we spent the week of the Queen's Diamond Jubi-
lee, which was heartily celebrated in every city and town of
, the realm. On the evening of Tuesday, June 22d, the chief
day of the celebration, a great bonfire blazed forth on the
summit of Skiddaw; and from that mountain top more than
sixty other beacon fires were visible on the mountains and
hills of all the surrounding country.
On the preceding Saturday I had ascended Skiddaw, find-
ing glacial striae in and near the path on the slate bedrock at
two places, about 50 and 100 feet above the upper hut, or by
estimate 1,950 and 2,000 feet above the sea, bearing, respect-
ively, S. 45° W. and S. 55° W. (as referred to the true merid-
ian, allowing 20° W. variation). The glaciation is doubtless
referable to ice flowing down the mountain slope, as no drift
foreign to the mountain is found there nor upward to its sum-
mit, 3,054 feet above the sea. Snow that had fallen in a storm
on Friday lay an inch or two deep on parts of the top; but the
cold and snows of that June were quite exceptional, almost
unprecedented within the memory of the oldest people.
Tuesday morning I set out to walk from Keswick to Hel-
♦Quart. Jour. Gfol. Soc, XXXI (1875), 55h)().
Valley Morauies and Drumlins, — Upham, 167
vellyn and Scawfell (two days' journey), but clouds resting
low on the mountains forbade the ascent of Helvellyn (3,118
feet). In the Thirlmere and Grasmere valley, through which
the road passes, between an eighth and a quarter of a mile
south of its highest point, called Dunmail Raise, I found a dis-
tinct valley moraine, a knolly transverse ridge of drift, the first
of many noted in the great valleys of this mountainous dis-
trict during my further journey to Scawfell and thence down
the Derwent valley to Keswick. This moraine has a hight
of about 20 feet, a length of nearly 1,500 feet, extending up
the inclosing mountain slopes, and a width of 200 to 300 feet.
It consists of till, with many boulders up to five feet in diam-
eter, and a few up to ten feet. A larger moraine of similar till,
having nearly the same length, but covering a much wider
space with its knolls and hillocks, 30 to 75 feet in hight above
the bedrock, crosses this valley a third to a half mile farther
south ; but a quarter to a third part of each moraine has been
swept away by the stream. The crest of the road is noted on
the Ordnance map as 783 feet, and these moraines are between
800 and 700 feet above the sea.
Near Grasmere village and lake three drumlins were seen,
one 30 feet high being close west of the road about three-
fourths of a mile north of the village; another, about 100 feet
high, forming the top and greater part of the Butharlip How
hill, in the north edge of the village; and the third, about 90
feet high, on the east shore of the lake (206 feet above the sea).
Each of these drumlins has the typically oval form, with trend
in parallelism with the southwardly declining valley.
Crossing the ridge south of Grasmere, and advancing
thence west up the Great Langdale valley, I observed an ex-
ceptional depth of drift, perhaps a terminal deposit, on each
side of that valley near Elterwater village, one-fourth to three-
fourths of a mile northwest of the lake or tarn of this name.^
Along the next three miles west the valley bottom is an
alluvial plain a fourth to a third of a mile wide, with a very
gentle descent eastward, in part pro])ably marking the site of
a temporary antl shallow postglacial lake.
Farther west, as I advanced up the narrowing Mickleden
valley, a very noteworthy display of valley moraines was en-
countered from one mile to two miles beyond the Old Dungeon
1 68 TJie American Geologist March. i8»>
Gill hotel. These are crossed by the path to Scawfell, bein|^
at the southwest base of the craggy Langdale Pikes (peaks).
In the valley, between 400 and 600 feet above the sea, eight
or ten clearly defined transverse moraines of bouldery till arc
accumulated in small ridges and hillocks from 10 or 20 feet to
50 or 60 feet high. Above the more northwestern of these
moraines, a large deposit of till is spread upon the southwest
side of the valley, forming the surface of the Green Tongue,
a spur of Bow Fell, to a hight of 500 feet above the stream.
This glacial drift is covered with grass, and its bright green is
in marked contrast with the dark gray rock and talus slopes
of other parts of the mountain sides inclosing the valley.
In descending to Keswick from the rugged crest of Scaw-
fell Pike (3,210 feet), an equally interesting series of small
moraines is seen in the Derwent valley from the mouth of the
Sty Head Gill to Longthwaite church and hamlet. Alonj^
this distance of two miles, with descent of the river from soci
to 300 feet, approximately, above the sea, nine moraines were
found, five of small size being in the first half mile before com-
ing to the Seathwaite farm houses ; a most remarkable curving"
moraine, a half mile long, with abundant and large boulders,
at the Thornythwaite house, a mile farther down the valley ;
and three other knolly drift belts crossed within the last quar-
ter of a mile before coming to Longthwaite.
Probably these nine moraines were formed contemporane-
ously with the similar number in the Mickleden valley, the two
series being respectively the records of the receding Scawfell
glaciers, during the last stage of the Glacial period, on the
north and east sides of this highest mountain mass of the
Lake District. Below the Scawfell neve fields by which these
j^laciers were fed, their lengths, at the time of formation of
the lowermost in the series of moraines here noted, were only
about three miles on the north and one and a half miles on
the east. At nearly the same time the neve areas on Helvellyn
and on the great ridge running north from the Langdale Pikes
sent confluent glaciers into the southern part of the interven-
ing Thirlmere valley, forming the moraines close south of
Dunmail Raise, one and a half to two miles south of lake
Thirlmere.
Six drumlins were noted and mapped by me in Keswick
Valley Moraines and Drumlins. — Upliam. 169
and its vicinity, within a half mile north, northwest, west and
south of the town, and drumlinoid slopes of till rest on both
the northwest and southeast sides of the isolated rock knob
named Castle Head. Other drumlins await mapping within
one to two miles farther west and northwest, but none were
seen in attentive outlook from our train as we travelled thence
to Penrith, Carlisle, Melrose, Edinburgh, Aberdeen and In-
verness. Drumlins were afterward found admirablv devel-
oped, however, in Glasgow and its environs, to be described
in the next paper of this series.
The careful field observations and writings of J. Clifton
Ward* assure us that the Lake District mountains were a
center of glacial outflow during the culmination of the Ice
age in Great Britain, turning aside the Scottish ice-sheet and
its drift. Mingled with that drift in its continuation eastward
are Lakeland boulders, as the very distinct Shap granite, car-
ried over the Pennine Chain, and through its gaps, to the low-
lands of Yorkshire. The highest summits of Lakeland prob-
ablv remained as nunataks when the confluent British ice-
sheet attained its greatest extent and depth. Outflowing
glacial currents from this district, coalescing with the strong-
er currents of the surrounding general ice-sheet, seem quite
sufficient to account for the diverse directions of transporta-
tion of boulders in and around the district without referring
some of them to marine flotation of ice, as was supposed by
Ward. A great submergence, of which the shell-bearing drift
<leposits at high levels on Moel Tryfan and in other localities
were thought to bear testimony, is not needed for explana-
tion of the transportation of either the shell fragments or the
Lakeland boulders.
In North America we have scarcelv a similar case of dis-
l)ersal of boulders outward from a limited area, unless it be
in the radial glaciation of the less mountainous but larger
tract of Newfoundland, which appears to have been connected
only by an isthmus of ice with the main continental ice-sheet.
The highest mountains of New England and New York were
apparently overtopped by this ice-sheet when it became thick-
*Q. J. G. S., XXIX (1873), 422-441, with map; XXX ( 1874). ^6-104, with
map and sections: XXXI (1875), 152-166, with maps. Compare with J. E.
Marr's papers, Q. J. Ci. S., LI (18951, 35-48, and LII (i8t>6). 12-16, each
uith figures in the text.
I/O The American Geologist. March, im»*
est;* but at the end of the Ice age the Adirondacks and the
much larger region of the White and Green mountains, with
probably the greater part of iMaine, continued ice-covered
after the glacial blockade was melted through along the
Hudson-Champlain and St. Lawrence valleys. \ Still later
local glaciers, the last representatives of the departing ice-
sheet, comparable with those of the English Lake District,
existed in the Green and White mountains, forming in some
places admirable series of valley moraines accumulated by ice
flowing northerly, in directions opposite to the earlier general
glaciation.t
Our mountains in the glacial drift area are less interesting
than those of Great Britain as centers of drift dispersion, be-
cause through the greater p::rt of the Glacial period they
shared in the general southward ice movement; but they have
very significant later valley moraines, which, according to
Agassiz, rival the recent recessional moraines of the Rhone
glacier. A most inviting field for American glacialists is the
more thorough exploration and correlation of these last val-
lev moraines of the White, Green and Adirondack moun-
tains.
SOME METHODS OF DETERMINING THE POSITIVE
OR NEGATIVE CHARACTER OF MINERAL PLATES
IN CONVERGING POLARIZED LIGHT WITH
THE PETROGRAPHICAL MICROSCOPE.
BjDb. M.E. Wadswokth, Hougliton, Mich.
For the elementary work in petrography in the Michigan
College of Mines the laboratory is furnished with twenty-nine
Bausch and Lomb petrographical microscopes specially made
for the college, besides numerous other microscopes and
petrographical apparatus, making it one of the best equipped
laboratories known.
♦Appalachia, V (i88q), 2QI-312 [also in the Am. Geologist, IV, Sept.
and Oct., 1889].
tAm. Jour. Sci. (3), XLIX, 1-18, with map, Jan., i8(>5 [also, more fulK
in Twenty-third An. Rep., Gcol. Survey of Minnesota, for 1894).
IE. Hitchcock. Geology of Vt., I (1861), 82-87. L. Agassiz, Proc.
A. A. A. S., XIX (1870), 161-167 [also in Am. Naturalist, IV, 1870, and Ge-
ology of N. H., Ill, 1878]. C. H. Hitchcock, Geology of \. H., Ill, 230-
250. GJ H. Stone, Am. Naturalist, XIV, 209-302, April, 1880.
Character of Mineral Plates, — li adsworth. 1 7 1
In giving instruction in the use of the petrographical
microscope as a polariscope, I have found a few directions of
value to my students, — directions which I do not remember
of having ever seen published. Thinking that they might be
of some value to some of our readers who are interested in
optical mineralogy, these directions are published here. Since
by varying the powers, the petrographical microscope can
be used with mineral plates of any standard thickness, the
directions here given can be used with the ordinary polar-
iscope plates as well as those thinner ones prepared expressly
for use with the microscope.
I. Uniaxial Minerals,
When the mineral plate shows the common uniaxial cross
in converging light its positive or negative character can be
ascertained by means of the gypsum plate or quarts wedge,
as well as by the ordinary mica plate,
(/) Use of the Gypsum Plate,
Examine the mineral plate, which, in converging polarized
light, between crossed nicols, shows a dark cross or part of a
cross with or without colored rings or arcs. Insert the gyp-
sum plate in the slot in the body of the microscope above the
objective. The cross is then resolved into colored hyperbolas.
The central portion is red terminated on the ends with yellow
and bordered on the side by blue. If the blue that borders the
red lies on a line parallel to the axis of least elasticity, the
mineral is positive, but if it lies on opposite sides of this
line the mineral is negative. The g)rpsum plate is often
more satisfactory in its use than the mica plate for these de-
terminations.
(.?) Use of the Quartz Wedge.
Insert the quartz wedge thin end forward. When the
wedge is gradually pushed in the cross resolves itself into
colored arcs that cross the field of view from two opposite
sides of the field and pass out of sight on the other two sides.
These arcs follow each other in succession as the wedge is
pushed in. If these colored arcs advance towards the center
of a line parallel to the axis of least elasticity the mineral is
POSITIVE, But if they march toward the center from op-
posite sides of that line the mineral is negative.
1 72 The American Geologist, March, vm
The use of the quartz wedge is less liable to error than
either of the preceding; and besides it can be used in many
cases where the others give no results.
(a) If the uniaxial plate is cut so that it shows arcs of
rings, its positive or negative character can be determined
by placing the arcs so a line perpendicular to them shall make
an angle of 45** with the cross hairs. By use of the quartz
wedge, colored arcs or rings can often be brought into the
field, when otherwise none are seen. Push in the quartz
wedge with its axis of least elasticity tangent to the arcs. . If
the rings then move outwards with their convex side forwards,
and, in time, a black or partially black arc appears, the min-
eral is POSITIVE, but if the arcs move with their concave
sides forwards the mineral is negative.
As a check against any error, turn the wedge over and
push it in, so its axis of least elasticity will be perpendicular to
the arcs. If then the arcs move with the concave side for-
ward, the mineral is positive, but if they move with the
convex side forwards, and a black or partially black ring or
rings show, the mineral is negative.
(b) A uniaxial plate cut parallel to the vertical axis can
have its positive or negative character shown in converging
polarized light as follows: Place the plate at an angle of 45°
with the cross hairs so as to show the colored arcs or imper-
fect hyperbolas. Push in the quartz first with its axis of least
elasticity perpendicular to the vertical or optic axis of the
plate. If on pushing along the quartz wedge a dark hyperbola
is seen to pass over the field the mineral is positive.
:\gain, push in the quartz wedge with its axis of least elasticity
parallel to the vertical axis of the plate. If then a dark hyper-
bola is seen to traverse the field, the mineral is negative.
11. Biaxial Minerals.
In order to render intelligible the directions later given,
there is here stated the method published in the text books for
determining the positive or negative character of a biaxial
mineral plate.
If a line. of extinction of a biaxial plate properly cut is
placed parallel to one of the cross hairs, it shows a cross with
unequal arms; but if the line of extinction makes an angle of
Character of Mineral Plates, — Wadsworth. 173
45° with that cross hair, it shows two dark hyperbolas, whose
vertices or eyes mark the position of the optic axes. Accom-
panying the cross and hyperbolas are colored lemniscate fig-
ures. Oftentimes the hyperbolas are wanting and only the
colored lemniscates can be seen; but by the insertion of the
quartz wedge the hyperbolas can frequently be brought into
the field.
(a) The positive or negative character of this biaxial plate
can then be determined by placing the plate on the stage in
such a position that a line joining the hyperbola eyes or bi-
secting the lemniscates through their longest direction shall
form an angle of 45° with the cross hairs. Push in the quartz
wedge with its axis of least elasticity parallel to the line join-
ing the hyperbola eyes. If the hyperbola eyes open and move
toward the center of the lemniscate figure the mineral is
POSITIVE.
Push in the quartz wedge with its axis of least elasticity
perpendicular to the line joining the hyperbola eyes. If these
eyes open and move toward the center of the lemniscate fig-
ure, the mineral is negative.
Of course, if in either case the eyes contract and move out-
wards, this is proof, when the axis of least elasticity of the
quartz wedge is perpendicular to the line joining the hyper-
bola, that the mineral plate is. positive ; but if they move
outward when the axis of elasticity is parallel to the chosen
line, the mineral is negative.
This method is less satisfactory in practice than the one
where the eyes open and move inwards.
(b) The above method given in our text books can be
supplemented by one that can be employed in numerous cases
when both of the hyperbola eyes cannot be seen, but only one
of them or only the lemniscate arcs. In either of these cases
the positive or negative character of the mineral plate can be
ascertained; if one can determine the position of the line join-
ing the hyperbola eyes or optic axes, by the form of the inter-
ference figures, by the position of the larger arm of the cross
or by any other means. When this direction is observed,
place the arcs so that the direction of the line joining the
hyperbola vertices shall be perpendicular to, or bisect, them;
also have this line make an angle of 45° with the cross hairs as
174 The American Geologist. March, i898
before. Push in the wedge with its axis of least elasticity per-
pendicular to the arcs or parallel to the line joining the hyper-
bola eyes. If the lemniscate arcs move in towards the center
of the field with their convex side forwards the mineral is
POSITIVE.
Push in the wedge with its axis of least elasticity tangent
to the arcs or perpendicular to the line joining the vertices.
If the arcs then move in with their convex side forwards the
mineral is negative. If the arcs move outwards with their
concave side forwards the mineral in the first position of the
wedge is negative, and in the second position positive.
(c) If the distance between the hyperbola eyes is not so
great but that they lie within the field of view, the mica and
gypsum plates can both be employed to determine the positive
and negative characters when the lemniscate figure is placed
as before, with the line joining the hyperbola eyes forming an
angle of 45° with the cross hairs of the eye piece. Insert
either the mica plate with its axis of least elasticity parallel to
the chosen line, or else insert the gypsum plate with its axis of
least elasticity perpendicular to the chosen line. With either
plate in this position the arcs on one side of the hyperbola eyes
will enlarge and those on the other side contract. If the arcs
that lie on the inside of the eyes, or nearest the center of the
figure, enlarge, and those on the outside contract, the min-
eral is positive. On the other hand, if the arcs nearest the
center contract and the outside arcs expand the mineral is
negative. This method can be used with plates that have
too great an axial divergence to admit of their determination
when the unsymmetrical cross is placed with its arms parallel
to the cross hairs.
III. Chromatic Scale.
Many students find it difficult to follow the color scales
given in most text books of petrography owing to the numer-
ous subdivisions of the scales. This difficulty can be obviated
in part by each student making for himself a color scale suited
to his eyes and experience. It is found that many students
mistake their ignorance of the names of color tints for color
blindness. The scale is made by placing the quartz wedge on
the stage of the microscope with the nicols crossed. Then
Tfu Keweenawan in Minnesota. — Elftrnan. 175
push the wedge with its thin end forwards through the field of
view of the microscope. Note the colors as they rise in the
scale, as the successively thicker portions of the wedge pass
in view. The scale thus noted will be suited to the wedge
employed and to the student using it at that stage of his ex-
perience. The operation can be repeated with the nicols par-
allel if desired.
IV. Section and Plate.
I have found it convenient in practice to distinguish the
terms "section" and "plate" in the microscopic study of min-
erals and rocks as follows:
The term "section" is employed to indicate the entire mass
of the rock or mineral that is carried by the glass slide used on
the stage of the microscope. The term "plate" is introduced
to designate a particular section or slice of mineral or other
substance that forms a part of the rock or general mass car-
ried by the glass slide. A "section" is composed of "plates."
A rock "section" is usually made up of many mineral "plates'*
either held together by intercrystallization or by some cement-
ing material which material in its turn lies in an irregular
"plate" or in "plates."
"Plate" is never the equivalent of "section," unless a single
"'plate" of one mineral forms the entire "section."
THE GEOLOGY OF THE KEWEENAWAN AREA IN
NORTHEASTERN MINNESOTA. II.
Hy A. H. Et.ptmak, Minneapolis.
Part II. GEOLOGY OF THE KEWEENAWAN SERIES.
Chapter L .Stratigraphy.
/. Historical Reineu\
The Keweenawan rocks of northeastern Minnesota are
distributed over an area of about 4,500 square miles, and con-
siderable has been written concerning this area. In view of
the great diversity of opinions expressed, and as much that
has been written consists of details regarding the geographi-
cal distribution of the diflferent members of this series, and
1/6 The Americafi Geologist. March, i88i<
also because this paper attempts in part to reconcile conflict-
ing opinions, it has been thought best to present a brief state-
ment of the results reached by each investigator. The term
Keweenawan, as used by the writer, covers the rocks included
by Irving in this series. At the end of this chapter is a list of
papers relating to the geology of this area.
Norwood,* in 1852, gives many details as to the geology
of the Minnesota coast of lake Superior. Some of the rocks
were considered to be of igneous origin, but the greater part
were referred to as metamorphosed sedimentaries.
Eames,* in 1866, mentions trap, greenstone, sandstone
and metamorphic rocks.
Kloos," in 1871, mentions the gabbro at Duluth and the
porphyry tes along the Minnesota coast. The same author,*
in 1 87 1, describes gabbro, melaphyre, porphyries, amygdaloids
and dike rocks in the vicinity of Duluth; and also,* in 1877,
further describes the igneous rocks at Duluth, and shows that
the melaphyre passes insensibly into the amygdaloids.
Streng and Kloos,' in 1877, give a petrographical de-
scription of several rocks from Duluth. The igneous rocks
at the western end of lake Superior are referred to the Pots-
dam age.
Winchell (N. H.),^ in 1879, refers the igneous rocks
along the Minnesota coast of lake Superior to the Cupri-
ferous series. These rocks are associated with extensive
metamorphic shales, sandstones, quartzytes and conglomer-
ates.
Winchell (N. H.),' in 1880, regards the Cupriferous
series as Potsdam. The gabbro at Duluth is intimately asso-
ciated with a metamorphic syenitic granite. All stages of
metamorphism, from the crystalline granite to the unchanged
sedimentary layers, were noted.
Hall (C. W.),' in 1880, finds the Cupriferous series, be-
tween the mouths of Temperance and Devil's Track rivers on
lake Superior, to consist of basic igneous rocks and inter-
hedded strata of sandstone and conglomerate. The Sawteeth
mountains are due to combined igneous action, the folding
of sedimentary strata, and erosion.
Sweet,'"* in 1880, describes the Keweenawan series in the
Saint Louis river valley. The eruptive rocks are bedded.
The Keweenawan in Minnesota. — Elftman. I ^^
varying from a foot to many feet in thickness. The Keweena-
wan rests unconformably upon the Saint Louis river slates
and is older than the lake Superior red sandstone.
Winchell (N. H.)," in 1881, gives many details observed
along the lake Superior coast from Duluth to Pigeon point.
The same author," in 1881, in a discussion of the rocks of
northeastern Minnesota, considers the acid red rocks forming
the Palisades, and occurring extensively in the vicinity of
Grand Marais and in numerous other places, to be meta-
morphosed sandstone, red shales and conglomerates. "On
])assing inland from the lake shore back of Grand Marais, and
up the Devil's Track and Brule rivers, the red semi-meta-
morphic slates of the shore can be followed over a wide ex-
tent of territory, gradually becoming mere changed and
crystalline in receding from the lake shore.'' The same au-
thor," in 1882, adds numerous details concerning the geo-
graphical distribution of the Cupriferous. The gabbro, which
is found to have wide extent, and its associated red granites,
are considered as a part of this series.
Irving," -in 1883, gives a systematic account of the cop-
per-bearing rocks of lake Superior, and the petrographical
characters of the different members of the series are given in
detail. The Kew^eenawan beds in Minnesota are referred to
the lower division of that series. The following six subor-
dinate groups, having a total thickness of upwards of 20,000
feet, represent this series.
1. The Saint Louis River gabbro and associated red
porphyries. This group comprises the basal gabbro, and con-
sists of orthoclase-gabbro, orthoclase-free gabbro, fine grained
diabase, augite syenite, granitic porphyry and felsitic por-
phyry. The thickness was estimated at about 6,000 feet.
2. The Duluth group. This group was recognized at
both ends of the Minnesota coast, and has a maximum thick-
ness of 5,000 feet. It consists largely of a succession of heavy
but sharply defined beds of fine grained rocks belonging to
the ashbed diabases and diabase porphyrytes. Coarse grained
orthoclase-free gabbro, thin amygdaloids and a little inter-
leaved detrital matter are also present.
3. The Lester River group. This group was recognized
at both ends of the coast, and has a thickness of 2,600 feet.
178 The American Geologist. March, ises
It consists of distinct beds of diabase porphyryte, diabase^
amygdaloid, coarse grained gabbro and granite porphyry.
4. The Agate Bay group. This group forms the coast
line for 35 miles below the mouth of Lester river, and has a
thickness of 1,500 feet. It consists of relatively thin beds of
diabase, olivine diabase, diabase porphyryte, amygdaloids,
sandstones and conglomerates.
5. The Beaver Bay group. This group is found at both
ends of the coast, and has a maximum thickness of 6/xx) feet.
It consists of beds of bjack, coarse grained, olivine gabbro.
ashbed diabases, diabase porphyrytes, amygdaloids, red felsitic
porphyries and granite-like rocks.
6. The Temperance River group. This group forms the
middle of the Minnesota coast, and has a thickness of 2,500 to
3,000 feet. In its composition and structure it is analogous
to the Agate Bay group.
The igneous origin of all the rocks, excepting a few thin
beds of sandstone and conglomerate, is emphasized. Num-
erous faults are mentioned, but none with a displacement of
over 100 feet were recognized. The absence of volcanic ash
was noticed. The eruptive rocks include basic, intermediate
and acid kinds, but there is no such chronological relation be-
tween these as is often found in more recent eruptives. The
series rests unconformably upon the Animikie or Upper Hu-
ronian slates in the Saint Louis river valley and in the vicinity
of Grand Portage bay.
Winchell (N. H.)," in 1884, refers the igneous gabbros
and dolerytes, together with their metamorphic products, to
the Potsdam formation. The same author," in 1885, finds
the Animikie slates and quartzytes overlain by the gabbro
and red granite of the Mesabi range, which is in turn over-
lain by the trap rocks of the Cupriferous.
Winchell (Alex.)," in 1887, gives detailed observations
made on an extensive trip in northeastern Minnesota. The
northern limit of the gabbro was determined in a number of
localities, and some peculiar contact rocks were noted.
Winchell (N. H.),"* in 1887, gives many details and pub-
lishes a preliminary geological map of a part of northeastern
Minnesota embodying the results of the field investigation up
to that time. The gabbro lies unconformably upon the Anim-
ikie, Keewatin and granitic rocks associated with these.
The Keweenawan i?t Muuiesota. — Elftma7i. 179
Wadsworth/* in 1887, gives petrographical descriptions
of many of the Keweenawan rocks.
Irving,"* in 1887, emphasizes the structural break be-
tween the Huronian and the Keweenawan formations. The
Potsdam sandstone rests upon the eroded surface of the Ke-
weenawan, The same author," in 1888, published a geo-
logical map of northeastern Minnesota. The Keweenawan
is divided into two large divisions, the basal gabbro and the
remainder consiisting of the upper five groups described in
1883.
Winchell (Alex.)," in 1888, gives further details of the
gabbro area along its northern limit.
Winchell (N. H.),"*^ in 1888, describes the rocks along
the northern boundary of the gabbro from Gunflint lake west-
ward. The trap (gabbro?) lies upon the Animikie in many
places. The gabbro lies upon the Pewabic quartzyte and the
Keewatin formations. The Pewabic quartzyte is placed above
the Animikie. The same author,** in 1889, gives a summary
of the results of work on the crystalline rocks in northeastern
Minnesota. The gabbro, red rocks and Keweenawan rocks
are referred to the Paradoxides horizon of the Potsdam age.
In general the conclusions and facts presented agree with
those expressed in earlier reports.
Winchell (H. V.)," in 1889, gives many details regard-
ing the geographical distribution of the Keweenawan. The
gabbro embraces large fragments of Animikie quartzyte and
slate, thus showing its later origin. The gabbro is intersected
by greenstone dikes, and in places gave the impression that
it is on top of the Cupriferous, and hence more recent.
Grant,* in 1889, gives numerous details regarding the
geographical extent of the Keweenawan. The gaboro is cut
by veins or dikes of syenite, and the contact between these
rocks is always distinct. Portions of the Animikie beds are
included in the gabbro.
Winchell (N. H.) ," in 1889, considers the basic eruptives
consisting largely of gabbro and following the Animikie, Jmd
those of the Cupriferous formation as representing separate
epochs of eruptive activity.
Winchell (N. H. and H. V.)," in 1890, describe the
gabbro titaniferous magnetites of the Mesabi range.
■ • * • w. *
•1 '
— rv-^c* ''TIC x-
• I - 1,' »;
• I '■'» 1 1 irii
»:.
The KeweeTiawan in Minnesota. — Elftman, . i8i
Lawson," in 1893, shows that the trap sheets associated
with the Animikie slates are intrusive sills whose age is con-
sidered to be post-Keweenawan (Keweenian). On the Cana-
dian side of lake Superior these sills were found in the Ke-
weenawan, and the author states his opinion, **that many of
the heav.y sheets of dark diabase or gabbro which prevail on
the Minnesota coast, particularly in its eastern portion, and
which have been described and referred to by former ob-
servers as volcanic flows of Keweenian age, are laccolitic
sills."
Bayley,*"" in 1893, gives in detail the petrography, rela-
tions and field occurrences of the eruptive and sedimentary
rocks of Pigeon point. Bayley," reviews the basic, massive
rocks of the lake Superior region. The great gabbro of
northeastern Minnesota, whose petrographical characters are
described with considerable detail, has a typical granitic struc-
ture and shows the characters of an intrusive rock. It differs
essentially from all of the basic intrusive rocks of the Anim-
ikie and from all other Keweenawan basic rocks, none of
which have a typical granitic structure. Along the northern
border of the gabbro are peculiar basic and quartzose rocks
which are regarded as peripheral phases of the gabbro. The
author concludes that further field work will probably show
that the gabbro is either a batholite, well toward the base of
the Keweenawan series, or that it is an eroded mass upon top
of which the later Keweenawan beds have been deposited.
Grant," in 1894, states that the gabbro varies in miner-
alogical composition, at times being entirely composed of
feldspar and again exceedingly rich in olivine. The gabbro
contains fragments of the Animikie slates. The fine grained
gabbros are older than the main mass. of the gabbro. The
acid eruptives in the vicinity of Brule lake are later than the
gabbro and probably represent the deep seated magmas that
produced the extensive acid surface flows seen along the Min-
nesota coast.
Elftman,** in 1894, divides the Keweenawan into the
gabbro, diabase, red rock and later dike groups. The anor-
thosytes of the Minnesota shore of lake Superior are shown
to be detached blocks inclosed in later trap rocks, and they
do not represent the eroded surface of an older formation.
1 82 The American Geologist March, i898
Grant,** in 1894, describes the conglomerates on Grand
Portage island, and places it at the base of the Keweenawan.
Elftman,** in 1895, describes the bedded and banded
structure of the gabbro and an area of troctolyte.
Winchell (N. H.),** in 1895, states that the eruptive rocks
in Michigan, Wisconsin and Minnesota which have been in-
cluded in the Keweenawan consist of two widely different
series, of widely separated ages. The older of these series, the
Norian, includes the great gabbro mass, augite syenites, the
quartz-porphyries of the Great palisades and elsewhere along
the Minnesota coast, and the anorthosytes. The more re-
cent or Keweenawan proper includes the basal conglomerate
at Grand Portage island, at Baptism river and at Duluth, and
the later trap flows, some of which pass below the Norian
rocks at the Great palisades. The "black rocks" in the Brule
lake region are regarded as part of the Animikie slates.
Van Hise,*' in 1893, 1895 and 1896, reviews and com-
ments upon current pre-Cambrian literature.
Winchell (N. H.),*" in 1897, discusses the nature and po-
sition of the conglomerate in the Puckwunge valley. This
conglomerate is correlated with that at Grand Portage island.
Baptism river and Duluth. The unconformity below this con-
*
glomerate separates the Norian from the Keweenawan.
Winchell and Grant,** in 1896, describe volcanic ash.
2. Results of the Present Investigation,
The preceding review of the literature upon the Keweena-
wan of northeastern Minnesota shows the existence of a great
diversity of opinions as to the proper subdivision of this series.
All admit that several subdivisions are possible. Thus far no
two geologists who have written concerning this area have
agreed upon this point. The observations were confined
largely to a narrow strip along the lake Superior coast and
the northern half of the gabbro mass. Between these limits
the region remained practically a "terra incognita."
The writer, in 1893, began to map this formation for the
Geological and Natural History Survey of Minnesota, and
has devoted the greater part of five seasons of field study to
this work. It soon became apparent that none of the suggest-
ed subdivisions could be followed to any extent. Nearly all of
714^ Keweefiawan in Mitmesota. — Elftman. 183
them had some points which could be recognized over the
entire area. The "terra incognita" usually did not show the
phenomena which had been predicted for it. The following
brief outline is given in order that the reader may better un-
derstand the detailed descriptions as they are given in th'e suc-
ceeding chapters. The results given below are based entirely
upon the writer's investigation and the petrographical descrip-
tions of the groups are taken from the series of rocks collected
by the writer for the Minnesota Survey.
An important obstacle in the way of getting a satisfactory
subdivision of the Keweenawan has been the failure to recog-
nize the extent of the faulting. It is evident that there is a
belt near the lake Superior coast which contains a series of
faults, some of which show a displacement of over 1,000 feet.
This belt is conspicuous for its peculiar topography and is
known as the Sawteeth mountains.
The proposed subdivision of the Keweenawan series is
based upon the chronologic succession, the stratigraphic con-
tinuity and the distinctive lithologic characters of each
member. The eruptive rocks of each member possess a
strong similarity in lithologic characters and are closely al-
lied in their genetic relationship. This suddivision elimi-
nates the supposed promiscuous chronologic relations of
the acid, basic and intermediate eruptive rocks. The mem-
bers, here proposed, are, in order of their age, the Gabbro,
the Beaver Bay Diabase, the Red Rock, the Temperance
River and the Later Diabase.
The Gabbro member. This includes essentially the basal
gabbro of Irving and the gabbro of the Mesabi hills of Win-
chell. It is entirely of an intrusive nature and appears to be
one mass, the proportion of whose mineral constituents vary
so that locally well defined varieties of the rock are recog-
nized. On its northern side the gabbro is in contact with pre-
Keweenawan formations, and on its southern border it is asso-
ciated with later members of the Keweenawan series.
The Beaver Bay Diabase member. This member has not
been found in contact with the preceding member. The area
between the two is occupied by parts of the later members.
In the vicinity of Brule lake are some rocks which may pos-
.sibly be older than the gabbro, but these are not associated
1 84 The American Geologist, March, lfc»^
with the Beaver Bay diabase. The member consists chiefly of
the massive flows of coarse diabase which inclose the anor-
thosytes of the Minnesota coast. Above these are numerous
thinner flows of diabase, diabase porphyryte and amygda-
loidal diabase. In the upper part of the member are thin lay-
ers or patches of volcanic ash. It is evident that this member
consists of basic surface flows with more or less volcanic frag-
mental rocks. The rocks as exposed above lake Superior
show that during the accumulation of this member the sur-
face was not submerged beneath the ocean. The fragmental
rocks point toward a formation upon an exposed surface. The
position of this member in the series is such that it may be
regarded as contemporary with the gabbro. Both consist of
basic rocks; the one is intrusive and the other effusive. These
and other facts indicate that the (iabbro and Beaver Bay
Diabase members are complementary parts of one eruptive
epoch. In the present paper the two are considered as twc^
members in order to establish the individual characters of
each. When this is done a further correlation may be at-
tempted. The rocks included in this member include part of
the Duluth, Lester River, Agate Bay and Beaver Bay groupSr
of Irving. The name Beaver Bay Diabase is given to the
member because all of the essential characters appear in the
region of which Beaver Bay forms the central point. This
diabase also forms the greater part of Irving's Beaver Bay
group, and is usually referred to, by him, as "black olivine
gabbro.''
The Red Rock member. This consists of intrusives and
their equivalent effusivcs. The former include granite and
augite syenite which occur extensively in the region between
the preceding two members and as bosses and dikes within
the gabbro. Numerous dikes also cut the Beaver Bay diabase,
and extensive surface flows of quartz porphyry lie upon it.
All of the rocks are highly acid. The Red Rock member, so
named on account of the persistent red color of the rocks,
succeeds the Gabbro and Beaver liay Diabase members and
presents similar physical characters concerning its origin. The
member includes the red rocks associated with the Saint
Louis River gabbro, and parts of the Lester River and Beaver
Bay groups of Irving.
The Keweenawan in Minnesota, — Elfiman, 185
The Temperance River member. Between this and the
preceding members is a considerable unconformity. The
older members were extensively eroded. In places a con-
glomerate and quartzyte over one hundred feet in thickness
form the basal strata. Upon the quartzyte and contemporan-
eous with part of it are found basic and intermediate surface
flows. The flows which followed consist of diabase and •dia-
base porphyryte, with a strong development of amygdaloidal
structure in the upper part of each flow. Numerous inter-
bedded layers of sandstone, sometimes 250 feet thick, though
usually from a few inches to a few feet, are found in all parts
of the member. In certain parts of the older members are
found several areas of basic intrusive rocks varying in struc-
ture from that of a gabbro to that of a dia!>ase. These are
tentatively correlated with this member, and may probably
represent fissures or vents through which the surface flows
were ejected. Tlie land was submerged, and it is noticeable
that the volcanic activity decreased and the deposition of sedi-
mentary rocks increased toward the top of the formation. This
member includes the greater part of the Agate Bay, the east-
ern end of the Duluth and all of the Temperance River groups
of Irving. The unconformity at the base of the Temperance
River member, in places, has been identified by Prof. N. H.
Winchell as the division line between the Norian and the
Keweenawan. From the descriptions of these divisions, as
given by Prof. Winchell, it is evident that part of his Norian
belongs above and part of his Keweenawan belongs below this
unconformity.
The Later Diabase member. A large number of diabase
dikes and sills are found cutting all of the preceding members.
The areal distribution of these is comparatively small. Since
they are later than all of the rest of the Keweenawan at pres-
ent found in this region, they are thrown into a separate mem-
ber. These dikes may not all be of the same age. In this
member are included rocks which are found in all of Irving's
groups, especially the Duluth group south of Brule lake.
The "black rock" of Winchell forms a prominent feature of
the group. This group occurs at numerous places along
lake Superior coast and frequently is indistinguishable from
the black diabases which it cuts.
1 86 The Afnerican Geologist. March, itus
J. Bibliography of the Keweenawan Area in
Northeastern Minnesota,
1. Description of the geology of middle and western Minnesota;
including the country adjacent to the northwest and part of the south-
west shore of lake Superior; illustrated by numerous general and local
sections, woodcuts, and a map, J. G. Norwood. Report of a Geological
Survey of Wisconsin, Iowa, and Minnesota, 1852, pp. 209-418.
2. Report of the State Geologist on the metalliferous region border-
ing on lake Superior, Henry H. Eames. St. Paul, 1866, pp. 21. See
also. Geological reconnaissance of the northern, middle and other coun-
ties of Minnesota, Henry H. Eames. St. Paul, 1866, pp. 58. '
3. Geological rambles in Minnesota, J. H. Kloos. The -MinncsotJi
Teacher and Journal of Education, St. Paul, 187 1, vol. iv, no. 6.
4. Geologische Notizen aus Minnesota, J. H. Kloos, Zeitschrift der
Deutschen Geologischen Gesellschaft, 1871, Bd. 23, pp. 417-448,648-652,
map. Translated by N. H. Winchell, loth Ann. Rept. Geol. and Nat.
Hist. Survey of Minn., 1882, pp. 175-200.
5. Geognostische vmd georgraphische Beobachtungen in Staate Min-
nesota, J. H. Kloos. Zeit. Gesell. fiir Erdkunde Berlin, 1877, Bd. 12,
pp. 266-320. Translated by N. H. Winchell. 19th Ann. Rept. Geol. and
Nat. Hist. Survey of Minn., 1892, pp. 81-121.
6. Ueber die krystallinischen Gestcine von Minnesota in Nord-
Amerika, A. Streng und J. H. Kloos. Leonhard's Jahrbuch, 1877, pp.
31, 113, 225. Translated by N. H. Winchell. nth Ann. Rept. Gcol. and
Nat. Hist. Survey of Minn., 1884, pp. 30-85.
7. Sketch of the work of the season of 1878, N. H. Winchell. 7tli
Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1879, PP- 9-25.
8. The Cupriferous series at Duluth, N. H. Winchell. 8th Ann.
Rept. Geol. and Nat. Hist. Survey of Minn., 1880, pp. 22-26.
9. Field report of C. W. Hall. Ibid., pp. 126-138.
10. Geology of the western lake Superior di&trict, E. T. Sweet.
Geol. of Wisconsin, 1880, vol. Ill, pp. 303-362, with an atlas map.
11. Preliminary list of rocks, N. H. Winchell. 9th Ann. Rept. .Geol.
and Nat. Hist. Survey of Minn., 1881, pp. 10-71.
\2. The Cupriferous series in Minnesota, N. H. Winchell. Proc.
.•\m. Assoc. Adv. Sci., 29th meeting, 1881, pp. 422-425. Same article in
9th Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1881, pp. 385-387.
13. Preliminary list of rocks, N. H. Winchell. loth Ann. Rept.
Geol. and Nat. Hist. Survey of Minn., 1882, pp. 9-122.
14. The Copper-bearing rocks of lake Superior, R. D. Irving.
LT. S. Geol. Survey, 1883, Monograph V, pp. 464, maps and plates.
Cliaptcr VII gives details concerning the Keweenawan in Minnesota.
15. Note on the age of the rocks of the Mesabi and Vermilion iron
district, N. H. Winchell. nth Ann. Rept. Geol. and Nat. Hist. Survey
of Minn., 1884, pp. 168-170. Also in Proc. Am. Assoc. Adv. Sci., 1884,
33rd meeting, 1884, pp. "^^Z-yj^-
16. Notes of a trip across the Mesabi range to Vermilion lake, N.
The Keweenawan in Minnesota. — Elftman, 187
H. Winchell. 13th Ann. Rept. Geol. and Nat. Hist. Survey of Minn.,
1885, pp! 20-24- The crystalline rocks of Minnesota, N. H. Winchell.
Ibid., pp. 36-38.
17. Report of geological observations made in northeastern Minne-
sota during the season of 1886, Alexander Winchell. 15th Ann. Rept.
Geol. and Nat. Hist. Survey of Minn., 1887, pp. 5-207.
18. Geological report of N. H. Winchell. Ibid., pp. 209-399.
19. Preliminary description of the peridotytes, gabbros, diabases and
andesytes of Minnesota, M. E. Wadsworth. Bull. 2, Geol. and Nat.
Hist. Survey of Minn., 1887', I59 PP-» and 12 plates.
20. Is there a Huronian group? R. D. Irving. Am. Jour. Sci., 3rd
ser., vol. XXXIV, 1887, pp. 204-216, 249-263, 365-374-
21. On the classification of the early Cambrian and pre- Cambrian
formations, R. D. Irving. 7th Ann. Rept. U. S. Geol. Survey, 1888,
pp. 418-423, and plate XLI.
22. Report of Alexander Winchell. i6th Ann. Rept. Geol. and
Nat. Hist. Survey of Minn., 1888, pp. I33-39I-
23. Report of N. H. Winchell. Ibid., pp. 13-129.
24. Report of N. H. Winchell. 17th Ann. Rept. Geol. and Nat.
Hist. Survey of Minn., 1889, PP- 5-74-
25. Report of H. V- Winchell. Ibid., pp. 77-145.
26. Report of Uly. S. Grant. Ibid., pp. 149-215.
27. Some thoughts on eruptive rocks with special reference to those
of Minnesota, N. H. Winchell. Proc. Am. Assoc. Adv. Sci., 1888, 37th
meeting, 1889, pp. 212-221.
28. The Taconic iron ores of Minnesota and of western New Eng-
land, N. H. and H. V. Winchell. Amer. Geol., 1890, vol. VI, pp. 263-
274.
29. Record of field observations in 1888 and 1889, N. H. Winchell.
18th Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1891, pp. 7-27.
30. The iron ores of Minnesota, N. H. and H. V. Winchell. Bull.
6, Geol. and Nat. Hist. Survey of Minn., 1891, pp. 430; with a geological
map of northeastern Minnesota.
31. Notes on the petrography and geology of the Akeley lake region,
in northeastern Minnesota, W. S, Bayley. 19th Ann. Rept. Geol. and
Nat. Hist. Survey of Minn., 1892, pp. 193-210.
2i2. Correlation papers — Arcliean and Algonkian, C. R. Van Hise.
Bull. 86, U. S. Geol. Survey, 1892, pp. 51-208. See also, An historical
sketch of the lake Superior region to Cambrian time, C. R. Van Hise.
Jour, of Geol., vol. I, 1893, pp. 124-128.
ZZ' Field observations on certain granitic areas in northeastern Min-
nesota, U. S. Grant. 20th Ann. Rept. Geol. and Nat. Hist. Survey of
Minn., 1893, pp. 35-95.
34. The Mesabi iron range, H. V. Winchell. Ibid., pp. 126, 127.
35. Nomenclature of the pre-Silurian rocks of Minnesota, N. H.
Winchell. 21st Ann. Rept. Geol. and Nat. Hist. Survey of Minn.,. 1893,
table on p. 5. See also pp. 143-152.
36. The geology of Kekequabic lake. U. S. Grant. Ibid., pp. 29, 30.
See also pp. 143-152.
1 88 The American Geologist March. i»8
37. The Norian of the northwest, N. H. Winchell. Bull. 8, Gcol.
and Nat Hist. Survey of Minn., 1893, pp. i-xxxiv.
38. The anorthosytes of the Minnesota coast of lake Superior, A. C.
Lawson. Ibid., pp. 1-23.
39. Laccolitic sills of the northwest coast of lake Superior, A. C.
Lawson. Ibid., pp. 24-48.
40. The eruptive and sedimentary rocks on Pigeon point, Minne-
sota, and their contact phenomena, W. S. Bayley. Bull. 109, U. S.
Geol. Survey, with maps and plates, Washington, 1893.
41. The basic massive rocks of the lake Superior region, W. S.
Bayley. Jour, of Geology, vol. I, 1893, pp. 433-456, 587-596, 688-716;
vol. II, 1894, pp. 814-825; vol. Ill, 1895, pp. 1-20.
42. Preliminary report of field work in 1893, U. S. Grant. 22nd
Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1894, pp. 76 and 7T.
43. Preliminary report of field work in 1893, A. H. Elftman. Ibid.,
pp. 169-180.
44. Note on the Keweenawan rocks of Grand Portage island, north
coast of lake Superior, U. S. Grant. Amer. Geol., vol. XIl, pp.
437-438, 1894.
45. Notes upon the bedded and banded structures of the gabbro and
upon an area of troctolyte, A. H. Elftman. 23rd Ann. Rept Geol. and
Nat. Hist. Survey of Minn., 1895, pp. 224-230.
46. A rational view of the Keweenawan, N. H. Winchell. Amer.
Geol., vol. XVI, 1895, pp. 150-155. See also the series of articles
"Crucial Points in the geology of the lake Superior region," Amer.
Geol., 1895, vols. XV and XVI.
47. Reviews of pre-Cambrian literature, C. R. Van Hisc. Jour, of
Geol., vol. I, 1893, pp. 309-314; vol. Ill, 1895, pp. 710-721; vol. IV, 1896,
pp. 750-756.
48. Some new features in the geology of northeastern Minnesota, N.
H. Winchell. Amer. Geol., vol. XX, 1897, pp. 50, 51.
49. Volcanic ash from the north shore of lake Superior, N. H. Win-
rhell and U. S. Grant. Amer. Geol., vol. XVIII, pp. 211-213, i8g6.
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
Palceontologiska notiser. Af Gerhard Holm. (Geol. Foren. i.
Stockholm Forhandl., Bd. 19, Hft. 6, tabl. 8-9, s. 457-482, Nov. 1897.)
4. Om Bohemilla ( f) denticulata Linrs. och Remopleurides micro-
phthalmus Linrs. Tafl. 8.
5. Om skalspetsen hos Lituites. Tafl. g.
6. Om forekomsten af en Pterygoius i Dalarnes Ofersilur
In the first of these three notes, Dr. Holm revises the description of
Review of Recent Geological Literature. 189
a new species of trilobite from Jemtland, described and figured by Linn-
arsson (Geol. foren. f6rh., Bd, 2, s. 495, 1875?), ^^'^ W ^^"^ referred with
doubt to Barrande's genus Bohemilla, The author describes the revis-
ion of Barrande's work on the genus Bohemilla and family Bohemillido'
made by Dr. C. E. Beecher, based upon specimens in the Museum of
Comparative Zoology, at Cambridge, Mass., wherein he affirms that there
is no satisfactory basis for the genus Bohemilla and idixmWy Bohemillido' .
Of this determination of Beecher, Dr. Holm appears to approve.
The specimens which authenticate the species Bohemilla (?) dentic
ulata of Linnarsson, consist -of a head and a pygidium preserved in thi*
Swedish geological musem, at Stockholm. Dr. Holm, declares that this
species agrees better with the genus Angelina^ of Salter, than with any
other, and so refers it. He also refers to A, (or B,) d;nticulata the pyg-
idium connected by C. Wiman with Telephus bicuspis Ang.
Another species from the same horizon and district, Remopleurides
microphthalmus Linrs. should according to Dr. Holm be referred to Di-
cellocephalus. He figures also a head for Angelin's Centropleura serra-
ta, and claims that this also should be included in Dicellocephalus, as
has been done by other authors . There is quite a close resemblance
between this species and D. finalis Walrott of the Eureka district, Ne-
vada, as Dr. Holm points out.
But the advantage of referring these Ordovician species to Dicello-
cephalusy without limitation is questionable; they have not the cylindri-
cal glabella with transverse furrows of the typical species of Dicello-
cephalus of Owen and Hall. None of these species as shown by Hall
("Preliminary notice of the fauna of the Potsdam sandstone," of the
upper Mississippi valley) have more than two spines on the pygid-
ium. See also Trans. Roy. Soc. Can., Vol. X, p. 11.
While Dr. Holm has transferred one of Linnarsson's species of this
fauna of Jemtland to the above genus, he has removed another from it.
D. billingsi is transferred to the subgenus Parabolinella of Brogger. A
complete example also enables Dr. Holm to assert that the Triarthrus
jemtlandicus of Linnarsson is the same as Triarthrus becki Green.
5. ''On the apex of the shell in Lituites.'' Sections of the shell
of Lituites perfectus Wahl., of which figures are given, show the pecul-
iar courses of the siphon. It begins on the outer margin of the first
chamber, and about the fourth or fifth chamber becomes central; subse-
quently it works still further towards the inner side of the shell, and for
the first whorl is about a third from this side; subsequently it becomes
more central.
6. ''On the Occurrence of a Pterygotus in the Upper Silurian of
Dalecarlia.** Dr. Holm says fragments of a species of this genus were
collected by G. von Schmalensee from a dark grey limestone in the
above district in 1895, He refers the specimens to the species P. osili-
ensis Fr. Schmidt.
Dr. Holm's article is accompanied by two excellent plates showing
D. microphthalmus, D, serratus and Ufuitcs perfitus. G. F. m.
I go The American Geologist. March. iw«
A Revision of the Puerco Fauna, By W. D. Matthew. Bulletin
Amer. Mus. Natural History, vol. IX, Art. XXII, p. 259; New York, Nov.
i6th, 1897.
This article is the outcome of a careful study of the original material
on which the late Prof. E. D. Cope based his description of the Puerco
fauna. To this material has been added the collection of the Museum
expeditions of 1892 and 1896 under the guidance of Dr. J. L. Wortman,
so that the author has had exceptional opportunities to obtain a
thorough knowledge of this primitive fauna of the placental mammals.
Being the starting point in America so far ad is known of so many recent
orders of mammals this fauna, nothwithstanding the fragmentary con-
dition of most of the material, is of the greatest interest. In dealing
with it, Prof. Cope had to depend chiefly on jaws and teeth, and, even
with the new material gathered by the Museum expeditions, only for a
few forms can the skeletal characters be described.
Dr. Wortman has described the stratigraphy of the beds and written
a paper on the Edentata. The work of Dr. W. D. Matthew has con-
sisted in a rearrangement of the species and reduction of their number.
This removal of unsound species and readjustment of the remainder is a
most useful work, as giving a better basis for generalizations as to the
bearing of this fauna on later Eocene and other Tertiary mammals.
One important result of late studies and of this review is the discov-
ery that the Puerco -group really contains two faunas, contained in three
fossiliferous layers, to the two lower of which the name Puerco is now
confined, the upper being designated the Torrejon fauna. The com-
bined faunas contain the following element:
*'i. The Mesozoic group of Multituberculates culminates in the
Puerco and dies out in the Torrejon, true rodents coming in to take
its place.
"2. The main body of the fauna is composed of the primitive types
from which sprang the ungulates on the one hand, and the later crco-
donts and carnivores on the other. In the Puerco these two divisions
are hardly distinguishable; in the Torrejon they are clearly separable,
although still closely allied, and the subdivisions of each group are fore-
shadowed. But it must not be supposed that we have here the direct
ancestors of all the later types; on the contrary, there are comparatively
•few forms, even in the Wasatch, that are descended from known basal
Eocene species, and these are not the persistent types. It is clear that a
large addition to the fauna must be made before we will come across the
direct ancestors of most of the modern Ungulata. The basal Eocene
carnivores and ungulates were evolving into types corresponding to
the modern differentiation, but to a great extent analogous only, and
not ancestral.
"For such primitive carnivores the term Creodottta is universally used.
For the corresponding group of primitive ungulates the term Condyl-
arthra will here be used, making it nearly equivalent to the hypotheti-
cal Protungulata,
Review of Recent Geological Literature, 191
"3. A few more specialized lines may be separated from
this main group. The Edentata are already well advanced in their
iliflFerentiation. The AmblyPoda and Rodentia are just beginning, but
clearly recognizable. A fourth type is allied to the Primates^
Two tables are given — one to exhibit the relation of the Puerco and
Torrejon faunas to the later Tertiary faunas. This shows "the differ-
ence between the Puerco and Torrejon faunas to be mainly in the pov-
erty of the former in families. This is not due to any scarcity of speci-
mens or specie3; it points to a large immigration at the beginning of the
Torrejon. Another considerable immigration must have taken place
before the beginning of the Wasatch."
The second table shows the families and species of the animals of the
Puerco and Torrejon and the number of examples of each species ex-
amined/ in some cases over one hundred. Thirty-one species are reck-
oned to the Puerco and forty-four to the Torrejon. Most of these
species were originally described by Cope, four are ascribed to Osborn
and Earle, and one to Wortman; two new species are described by Dr.
Matthew, and another distinguished but not described.
There are several suggestive discussions of genera and families, espec-
ially the ? Rodentia (p. 265) Triisodontidce (p. 277) Ctenodon (p. 291) Con-
dylarthra^ (p. 293 and 321) Anisonchina (p. 297) Phenacodcntidce (p. 299)
EuProtogonia (p. 305) MiocioenidiE (p. 311), also a note on the foot struc-
ture of the basal ^ocene mammal, on p. 320.
This article, with its full description of the archaic placentals of the
Puerco and Torrejon faunas, accompanied, as it is, by cuts showing the
dentition of most of them, and a full synonymy of the species, is a valu-
able addition to the history of the development of the Mammalia, and
a convenient compendium for the student of these vertebrates,
G. F. M,
Geology of Massanutten Mountain in Virginia. By Arthur Coe
Spencer, (Pamphlet, pp. 54, 3 plates and map Washington, 1897.)
Among the dissertations that have recently been issued there are
none of greater interest than that on the geology of Massanutten moun-
tain by Arthur Coe Spencer, of the Johns Hopkins University. It deals
with a problem that is ordinarily much too large for the thesis required
as the final outcome of graduate work in the university. But the treat-
ment is as full and admirable as the subject matter is interesting and
instructive. The area treated of is eight miles wide by forty-five miles
long, lying between two parallel branches of the Shenandoah river.
After a general description of the main topographic features of the
surrounding region, the stratigraphy, lithological characters, structure
and local relief are considered. The principal effort is placed on the
geological history of the region as elucidated by Massanutten. The
conclusions are briefly summarized as follows: (i) After the deposition
of the Cambro-Silurian limestone a land area was elevated opposite the
region studied, with its seaward boundary in the vicinity of the present
Blue ridge; (2) subsequent to this early revolution there were many
192 The Americmi Geologist. March, is^
oscillations of the shore line resultant upon alternating elevation and
subsidence, but the average position of the coast was not greatly
changed from the position first assumed, for it was now on one side
and now on the other of the Martinsburg shore; (3) the Massanutten
syncline marks the site of an off-shore zone of maximum deposition,
and is therefore illustrative of the hypothesis of original synclines;
(4) the general post- Carboniferous folding of the Appalachian province
was shared by the Massanutten region; (s) since Paleozoic time the
region has been several times elevated, suffering, during the intervals
between the uplifts, more or less complete degradation, at least three
and perhaps four such uplifts being recognized in remnants of base level
surfaces; (6) the latest upward movement of the land has been so recent
that its effect is still evident in the grades of the rivers of the region.
Not the least valuable features of the paper are the synoptic arrange-
ment throughout, terseness of statement, and the general absence of all
those unnecessary details which so often burden most literature of this
kind.
MONTHLY AUTHORS' CATALOGUE
OF American Geological Literature,
Arranged Alphabetically.*
Agassiz, Alexander.
The islands and coral reefs of the Fiji group. (Am. Jour. Sci., ser.
4» vol. 5, pp. 1 13-123, Feb. 1898.)
Blake. W. P.
Native sodium carbonate. (Eng. and Min. Jour., vol. 65, p. 188,
Feb. 12, i8g«.)
Campbell, M. R.
Earthquake shocks in Giles Co., Va. (Science, new ser., vol. 7, pp.
233-235, Feb. 18. 1898.)
Cohen, E.
Uber ein neues Meteoreisen von Locust Grove, Henry Co., Xord-Car-
olina, Vereinigte Staaten. (Sitzungsb. d. k. preus. Akad. d. Wissensch.
zu Berlin, phys.-math. Cl., 1897, VI, pp. 76-81.)
Cohen, E.
Das Meteoreisen von Forsyth Co., Georgia, Vereinigte Staaten.
(Sitzungsb. d. k. preus. Akad. d. Wissensch. zu Berlin, phvs.-math.
Cl., i8q7> XVI, pp. 386-396.) '
*This list includuB titles of articles received up to the 20tli of the ureoediofr
month, includinflr general ffeolovy, physiography, paleoiitol«>»fy, petrology and
mineralogy.
Authors' Catalogue. 193
Elftman, A. H.
The geology of the Keweenawan area in northeastern Minnesota.
(Am, Geol., vol. 21, pp. 90-109, pi. 11, Feb. 1898.)
Ells, R. W.
Formations, faults and folds of the Ottawa district. (Ottawa Nat-
uralist, vol, 9, pp. 177-189, Jan. 1898,)
Ells, R. W.
Recent conclusions in Quebec geologv. (Ottawa Naturalist, vol.
II, pp. ^Jy^y^f Dec, 1897.)
Gilbert, G.K.
A proposed addition to physiographic nomenclature. (Science, new
sen, vol. 7, pp, 94-95, Jan. 21, 1898.)
Gilpin, E., Jr.
Some analyses of Nova Scotia coals and other minerals. (Trans.
Nova Scotian Inst Sci., vol, 9 [2nd scr., vol. 2], pt 3, pp. 246-254,
Nov. 30, 1897.)
Gresley, W. S.
Clay-veins vertically intersecting Coal Measures, ((jcol. Soc. Amer.,
Bull, vol. 9, pp. 35-58, Jan. 18, 1898.)
Kemp, J. F.
The Montreal meeting of the Geological Society of America. (Sci-
ence, new sen, vol. 7, pp. 4^53, Jan. 14, 1898; pp. 79-85, Jan, 21, i808.)
Kummel, H. B.
The age of the artifact-bearing sand at Trenton. (Science, new ser.,
ine age ot tne artitact-Deanng
vol. 7, pp. 115-117, Jan. 28, 1898.)
Marbut, C- F.
Cote Sans Dessein and Grand Tower. (Am. Geol., vol. 21, pp. 86-90,
pi. 10, Feb.. 1898.)
Orton, Edward.
Geological probabilities as to petroleum. President's address. (Geol.
Soc. Amer., Bull, vol. 9, pp. 85-100, Jan. 24, 1898.)
Pratt, J. H.
Mineralogical notes on cyanite, zircon, and anorthite from North
Carolina. (Am. Jour. Sci., ser. 4, vol. 5, pp, 126-128, Feb. i808.)
Prosser, C. S,
The Permian and Upper Carboniferous of southern Kansas. (Kans.
Univ. Quart., vol. 6, pp. I49-I75, pls. 18-19, Oct 1897.)
Roy, Andrew.
Geology of the Jackson County coal in Ohio. (Eng. and Min.
Jour., vol. 65, p. 164, Feb. 5, 1898.)
Ruedemann, R.
Synopsis of recent progress in the study of graptolites. (Am. Nat,
vol. 32, pp. i-i6, Jan. 18S98.)
194 TJu American Geologist. March, 189^^
Ruedemann, R.
Additional note on the oceanic current in the Utica epoch. (Am.
Geol., vol. 21, pp. 75-81, pi. 9, Feb. 1898.)
Sherzer, W. H.
Limestones of southeastern Michigan, with their associated sand-
stone, salt, and gypsum [Abstract], Geol. Soc. Amer., Bull., vol. 9.
pp. 10- n, Dec. 30, 1897.)
Spencer, A. C.
The geology of Massanutten mountain in Virginia. (A thesis pre-
sented to the board of university studies at Johns Hopkins Universit>
for the degree of Doctor of Philosophy, May, 1896. 54 pp., 4 pis. ; pub-
lished by the author, Washington, 1897.)
Spencer, J. W.
On continental elevation of the Glacial epoch. (British Ass. Adv.
Sci., Sec. C, Toronto, 1897; 2 pp.)
Spencer, J. W.
Great changes of level in Mexico and the interoceanic connections.
(Geol. Soc. Amer., Bull, vol. 9, pp. 13-34, pis. 1-5, Dec. 31, 1897.)
Spencer, J. W.
An account of the researches relating to the Great lakes. (Am.
Geol., vol. 21, pp. 1 10- 123, Feb. 1898.)
Taylor, F. B.
Origin of the gorge of the Whirlpool rapids at Niagara. (Geol.
Soc. Amer.,. Bull., vol. 9, pp. 59-84, Jan. 24, 1898.)
Udden, J. A-
Loess as a land deposit. (Geol. Soc. Amer., Bull., vol. 9, pp. 6-9,
Dec. 30, 1897.)
Upham^ Warren.
Niagara gorge and Saint Davids channel. (Geol. Soc. Amer., Bull.,
vol. 9, pp. loi-iio, Jan. 25, 1898.)
Upham, Warren.
Shell-bearing drift on Moel Tryfan. (Am. Geol., vol. 21, pp. 8i-86.-
Feb. 1898.)
Wadsworth, M. E.
Zirkelyte: A question of priority. (Am. Geol., vol. 21, pp. 133-134.
Feb. 1898.)
Wadsworth, M. E.
Some methods of determining the positive or negative character of
mineral plates in converging polarized light with the petrographical mi-
croscope. (Jour. Applied Microscopy, vol. i, pp. 20-21, Feb. i8g8.)
IWalcott, C. D.]
Sketch of Charles D. Walcott. (Appletons' Pop. Sci. Monthly, vol.
52, pp. 547-553, portrait, Feb. 1898.)
Ward, H. A.
Four new Australian meteorites. (Am. Jour. Sci., ser. 4, vol. 5,
pp. 135-140, Feb. 1898.)
Correipondems.
Whitaker, M. C.
An olivinite dike of the Magnolia
Willis, Bailey.
Stratigraphy and structure of the Pugei group, Washington [Ab-
stmct. (Geol.Soc. Amer., Bull., vol. t), pp. 2-6, Dec. 30, 1897.)
CORRESPONDENCE.
Correlation of Mokaines with Beaches on the Border of
[.AKE Erie, In two papers published in the American Journal of
Science (April, 1892, and July, iSgs.) I have advanced the view that
certain moraines on the south and east borders of lake Erie are correla-
tives of beaches which encircle the western end of the Lake Erie basin,
an interpretation which signifies that while a lake was occupying the
district inclosed by these beaches, the ice-sheet was occupying districts
to the east. This interpretation was based upon studies carried on in
part by Mr. Gilbert and in part by myself, Mr. Gilbert's studies being
confined mainly to the beaches and mine to the moraines. Later studies
by Mr. Warren Upham, at Cleveland, and by Prof. H. L. Fairchild, in
western New York, the results of which are published in the Bulletin
of the Geological Society of America (Upham, Vol. VII, March, 1896,
pp. 340-345, and Fairchild, Vol. VIII, March, 1897, pp. 269-281), have
brought to light the continuation of these beaches to points farther east
than had previously been observed. It seems necessary, in view of these
observations, that a brief supplementary statement should be made. 1
am especially prompted to do this because Dr. Spencer has intimated
in the February American Geologist that these later studies have re-
moved the supposed evidence of ice occupancy of the eastern part of the
region during the formation of beaches in the western part, and that
they sustain his cherished view that the shore Unes are marine. In this
"diagnosis" Dr. Spenc'er departs from the views of Mr, Upham and
Prof. Fairchild, as well as from those of Mr. Gilbert and myself.
The view that the beaches in the western end of the Lake Erie
basin pertain to a glacial lake has been adopted after due consideration
of other hypotheses. The nature of the outlet has been carefully looked
into. The pioneer work by Mr. Gilbert, in the Maumee valley of north-
ghl to Ught the south-
was clearly recognized
bert likened the upper
ver, while the portion
I at BuRalo, where it
196 The American Geologist March, i698
rushes over the outcrop of the Corniferous limestone,, the descent being
comparatively . rapid (Geology of Ohio, Vol. I, 1873, P- 5So). So far as
I am aware, no subsequent observers have questioned the view that this
outlet is the product of a stream of water having rapid descent. The
outlet has been examined in some detail by Dr. C. R. Dryer, of the
Indiana Geological Survey, by Mr. F. B. Taylor, the well known glacial
geologist, and also by the present writer. The current was sufficiently
swift to sweep away the greater part of the detritus brought in by trib-
utary streams, as well as to excavate a channel in the glacial deposits
having an average width of about one mile and depth of 50 feet or
more. In this connection it may be remarked that outlets from basins
farther west have given equally clear evidence that the lakes which dis-
charged through them stood much above sea level. The Chicago outlet,
for example, presents rapids near Joliet, where a descent of seventy feet
was made in only nine miles.
At the time of the discovery of the Wabash outlet , Mr. Gilbert ad-
vanced the view that the lake was held in at the east by a land barrier,
and concluded "that the Wabash outlet is now, in its relation to the
other parts of the great rim, not less than 170 feet higher than it then
was." (See p. 551 of work cited.) The view subsequently advocated
by Mr. Gilbert, that the lake was held in by an ice barrier at the east,
was adopted only after it was found impossible to account for the pres-
ence of the lake by a land barrier. With this recognition of the high
elevation of the lake and the absence of a land barrier, has conje the
general assent to glacial dams as the only barrier available. And yet in
the article referred to, Dr. Spencer states (p. 118) that he has postponed
further study partly on account of the prejudice against post-glacial
subsidence, thus implying that the views held by the advocates of glacial
dams are due to prejudice rather than a result of logical reasoning.
Having now stated the conditions concerning the Wabash outlet and
the absence of evidence of a land barrier to account for the lake, we
may turn to the localities examined by Mr. Upham and Prof. Fairchild
and note the bearing which the further studies have upon the question
of the correlation of the moraines with beaches.
Mr. Upham has traced the Leipsic beach from Big creek valley in
the west part of Cleveland, where it had been supposed to terminate,
eastward -about seven miles to the east part of the city, and thence north-
ward two or three miles. He considers it likely that the shore may be
traced still farther and places a probable limit at Euclid, ten miles east
of the center of the city, where one of the moraines which I have de-
scribed fades out. Concerning the correlation of this beach with stages
of the glacial recession, Mr. Upham makes the following remarks:
"Mr. Leverett has proved the successive lake stages to have been
contemporaneous with stages of the glacial retreat defined by four
distinct moraines. The Leipsic beach he supposed to have been wholly
formed before, and during, the accumulation of the Newburg moraine.
Correspondence, 197
.... From Big creek westward the Leipsic shore displays perhaps^
three or four times more wave cutting and resultant beach gravel and
sand than in the vicinity of Brooklyn and east of the Cuyahoga valley.
There, however, it is unmistakably continued northeastward beyond the
more northern deposits of the Newburg moraine, so that the later
part of the Leipsic shore work was done after the ice-sheet had receded
from its Newburg boundary." (Bulletin, Geol, Society of America,
Vol. VII, pp. 344, 345.)
It remains to be determined whether the beach extends eastward
beyond the western terminus of the Euclid moraine. In case it is found
to be developed farther east along the face of the Euclid moraine, it
would follow that the lake was still maintained at this level after the
ice had withdrawn from the moraine, and the extent of the beach along
that shore will measure the distance to which the ice had withdrawn
before the lake level had become lowered. The question of the lowering
of the lake level, it should be noted, depends not upon the withdrawal
of the ice from the moraine, but upon the opening of a lower outlet.
TKis may have occurred either during the occupancy of the moraine
or subsequent to it; in either case it would not affect the question of
the existence of an ice barrier. The significant feature brought out by
Mr. Upham is the marked change in strength of the beach upon pass-
ing eastward within the limits of the supposed correlative moraine.
The portion west from (outside) the moraine is so strong that it has
long been recognized, while the portion east has been found only after
a series of close observations by a trained observer of beach phenomena;
and this observer renders the verdict that the recently discovered east-
ward extension of the beach displays only one-third or one-fourth as
much strength as the well known portion of the beach. The discrim-
inating study carried on by Mr. Upham has served to bring out the
relationship of the ice to the glacial lake more fully than my own
studies, but has not invalidated the conclusions concerning the presence
of an ice barrier at Cleveland.
The Belmore beach, as indicated in my second paper, probably ex-
tends eastward nearly to the eastern end of lake Erie. It is well de-
fined as far as Sheridan, New York, and may possibly continue to
Hamburg, though the beach is apparently less definite than west from
Sheridan. From Hamburg eastward, so far as has yet been discovered,
this beach has no continuation. Its probable correlation with moraines
near the east end of lake Erie is set forth in the paper referred to, and
so far as I am aware no evidence against this correlation has since been
discovered. Much light concerning the outlet of the glacial lake at the
stage when the Belmore beach was forming, has been shed by Mr.
Taylor's studies in southwestern Michigan (Bulletin, Geol. Soc. Amer-
ica, Vol. VIII, Jan., 1897, PP- 39-46). From these studies it appears
that at the time the Belmore beach was in process of formation the ice-
sheet still occupied lake Huron and Saginaw bay. The outlet of the
lake is found to have crossed the "thumb" of Michigan near its north-
iqS The American Geologist March. i8C8
ern p6int, and, after expanding into a small lake at the head of the
Saginaw Bay basin, to have entered Grand river along what has been
termed by Spencer the Pewamo outlet. Mr. Taylor's studies, as
well as mine, sustain the interpretation that the eastern and northern
boundaries of the lake were found in an ice barrier, and they apparently
bring out more clearly than mine the relationship of the ice to the lake.
It remains to speak of the results of Prof. Fairchild's studies of the
extent of lake Warren in western New York. The beach marking the
upper limit of that lake (called by the writer the Crittenden, but prob-
ably the equivalent of Spencer's "Forest beach") has been traced east-
ward, from the supposed termination near Indian Falls, beyond the
Genesee river. The eastern terminus is at present unknown. As at
Cleveland, the beach is less well defined east from the supposed correla-
tive moraines than west from them, vet there appears to have been more
wave action in the portion discovered by Prof. Fairchild. than in the
case of the Leipsic beach in the east part of Cleveland. The wave ac-
tion is sufficiently marked to have attracted my attention, though no
beach was noted in connection with it. This is set forth in the fol-
lowing statement taken from my paper in the American Journal of
Science (pp. 18-19):
"Upon examining the district eastward from northwestern Gene-
see county (where the Lbckport moraine and the Crittenden beach
intersect), we found a narrow belt at about the level of the Crittenden
beach where the drift forms seem to have been somewhat modified by
the action of waves or currents of water. This is considered a possible
lake level, or perhaps a lake outlet. There is a large amount of grav-
elly drift in this belt, but so far as discovered it is not arranii^ed in beach
lines, the surface being either plane or having a gentle undulation, as
if the drift knolls had suffered reduction or modification by waves or
currents. This gravelly drift occupies usually a breadth of two or three
miles. In places it occupies the entire interval between the Lockport
moraine and the drumlin belt which lies north of it"
Concerning the views expressed in my paper, Prof. Fairchild makes
the following remarks (page 271) :
"Some of the views guardedly expressed in that article are definitely
confirmed, while others require modification. The Lockport moraine
was, undoubtedly, the eastern limit of the Warren water for a con-
siderable time, and correlates with the formation of the beach south of •
Crittenden. But the withdrawal of the ice-front from that portion did
not produce immediate lowering of the water or terminate the beach-
making process at the Crittenden level. The zone of sand and gravel
drift described by Mr. Leverett as lying north of the Lockport moraine
is the shore deposit of the enlarged lake, and is definitely bordered by
the eastern extension of the beach.
"A comparison, as regards the time involved, of the beach east of
Indian Falls, with the beach westward, is very difficult to make on
account of the difference in the topographic relief. The Crittenden
Correspondence, 199
beach is much more mature, but it lies nearly parallel with the contours
of a comparatively smooth sloping plain, and the conditions favored
the rapid maturing of the shore line. Eastward from Indian Falls the
land surface is very uneven and the shore line lies transverse to the
drumlin molding, which conditions would require a much longer time
to straighten and mature the beach. With all allowances, the impres-
sion made upon the mind is that of somewhat less duration of the
beach-making forces in the Genesee region."
With any criticism of my work which brings out more refined de-
terminations than I have made I am in full sympathy. The studies by
Prof. Fairchild, Mr. Upham, and Mr. Taylor, just noted, have all been
helpful to a better understanding of the situation. No doubt as the
work continues much more refined and delicate discriminations will be-
come possible. Faith in the harmony of the universe inspires confi-
dence that the features of debatable origin, in which Dr. Spencer has
taken refuge as a defense against glacial dams (page 117) and which
have as yet received less attention than they merit, will some time be
found consistent with the already well established facts and principles
of geology, among which facts it seems safe to include glacial dams.
Opportunity is here taken to state that, in presenting the name Crit-
tenden for the principal beach of lake Warren, I had no intention of de-
parting from the usage of naturalists, as intimated by Dr. Spencer (page
119). For I doubted its being the precise equivalent of the Forest
beach. These doubts have in a measure been removed upon discussing
the matter with Dr. Spencer. Although continuous tracing has not a^
yet been made, there seems little question that the Crittenden beach
is the equivalent of the Forest. Such being the case the name Forest
has priority. It may also be remarked that the name Belmore, sug-
gested by Prof. N. H. Winchell, has priority over the name Ridgeway,
suggested by Dr. Spencer.
Denmark, Iowa, Feb, 9, iSqS, Frank Leverett.
A New Well at Rock Island, Ills,— A new well has lately been
drilled by the Rock Island Brewing company on its premises near the
crossing of Seventh avenue and Elm street in Rock Island, Ills. The
curb of this well has an elevation of about 654 feet above sea level, and
the water rose to within 44 feet of this hight. The first 100 feet of the
hole was mad^ twelve inches in diameter; the next 185 feet, eight
inches; the next 240 feet, six inches; and the last 764 feet, five inches;
the total depth of the well being 1,289 feet. There was a water-bearing
stratum in the Trenton limestone, but the water from this rock was sul-
phurous and was shut off by a casing extending down to 912 feet below
the top of the well. The drillers furnished me with a statement of the
nature of the rocks which were penetrated. This is here given, with
my own determinations in parentheses:
1. "Clay, 100 feet." (Loess and till, and possibly some coal-meas-
ure shale.) From 654 A. T. to 554 A. T.
2, **Limestone, 30 feet" (Devonian.) From 554 to 524.
200 The American Geologist, March, ifc^i*
3. "Limestone, with shale alternating, 395 feet." (The upper twenty
feet, or so, possibly Devonian limestone, the rest is Niagara limestone
with arenaceous shale in caverns.) From 524 to 129.
4. "Shale, 205 feet." (Hudson River shale.) From 129 to — "jd.
5. "Limestone, 330 feet.*' (Galena and Trenton limestone.) From
—76 to — 406.
6. "Blue clay, 25 feet." (Shale or clay associated with the St. Peter
sandstone.) From — 406 to — 431.
7. "Sand and some shale, 204 feet." (St. Peter sandstone with,
probably, some associated shale below.) From — 431 to — 635.
The several formations differ but slightly in thickness from the gen-
eral averages of ten other wells reported from this vicinity two years
ago.* In common with two other wells lying north of this one, this
boring exhibits a considerable amount of Coal Measure shale in pocket>»
in the Niagara hmestone. The overlying Devonian limestone is studdetl
with caverns filled in the same way, and these generally follow joints,
which have a north and south trend. From the nature of the filling,
which in the uppermost caverns appears to be continuous with the basal
sediments of the Coal Measures, it appears evident that these caves must
have been tunneled out either during the later part of the Devonian
age, when sedimentation in Devonian waters had ceased, or else during,
the Subcarboniferous age. The distribution of the rocks of this latter
age is such as to indicate that, at the time they were laid down, the
drainage of this region was from north to south. This coincides with
the observed trend of the filled caverns.
Rock Island, Ills, J. A. Udden.
Dec. 2g, iSgy.
PERSONAL AND SCIENTIFIC NEWS,
New York Academy of Scienxes, Section of Geology,
Jan. 17, 1898. Meeting opened with a paper by Mr. Ar-
thur Hollick, entitled '• F'urther Notes on Hlock island;
geolog}' and botany."
Mr. Hollick gave a summary of his work done on Block island in
July, 1897, and particularly of his success in tracing eastward from
Long island the Amboy clays which had previously been determined by
pal.Tontological evidence on Staten island. Long island and Martha's
Vineyard. Something like fifteen species of Middle Cretaceous flora,
nine of them typical of the Amboy clays, have been found. Mr. Hol-
lick then classified the existing flora of the island physiographically into
that of the hills, peat bogs, sand dunes and beaches, salt marshes and
^ salt water. In the course of his work he added to the already pub-
' lished lists something like twenty-four new species, although it is not
♦Vidp An nccnunt of the PaliiH)z<>ic Riicks, etc., 17th Ann. R«»i>t. ^' '^- <»o<)l. Surv.,
P. II, p. ¥29.
Personal and Scie?itific News. 201
considered that this by any means completes the list of possible species
that might be found in the spring. The flora as a whole is distinctly
that of a niorainal country, and its nearest analogue is that of Montauk
point. ,
Mr.' Hollick then offered some suggestions to account for the present
peculiar flora of the island, and particularly for the absence of certain
iipecies that would be expected, and showed that two features are to be
taken into consideration: the geological and the human. Block island
is the only part of the terminal moraine along the New England coast
which does not have accompanying the moraine a certain amount of
plain land, which would naturally allow a variety in the flora. It is
presumable that Block island also has been practically separated from
the rest of the continent by a deep channel of more than twenty fathoms
for a considerable time, and that even before the last depression of
land, the island was connected to the mainland merely by a small penin-
sula, and hence the diversity of the flora as compared with the conti-
nent because of the length of separation. The speaker also mentioned
^'xtensive archaeological discoveries on the west shore of the island.
and gave a list of the shells and implements discovered in several of the
kitchen middens, and also of the bones of animals l>rought to light in
the old fireplaces in the sand dunes. He made particular mention also
of the great number of Littorina, the common periwinkle of Europe
which has never before been announced from Block island. The paper
was discussed by Prof. Lloyd and Dr. Martin.
The second paper of the evening was by the secretary^
•entitled "Scientific geography in education."
The speaker brought out the point that geography work may be
classified into three divisions: that for the common schools, the sec-
ondary schools and the universities, and outlined briefly a few sug-
gestions as to how the subject matter might be treated scientifically
in each of the groups, and the dependence of each group upon the
others. He paid particular attention to the difficulties of securing scien-
tific work in geography in the grade schools, and to the fact that the
present work is extremely unsatisfactory in most of our schools, prob-
ably because of the lack of inspiration owing to the neglect of the sub-
ject hitherto in universities of the country. The paper was illustrated
by exhibition of cheap and easily procurable maps, that may be used for
scientific geography work of several grades.
The meeting then closed with a few remarks by the chair-
man in reference to the famous classic entitled **Lithograph-
iae Wircenburgensis dacentis lapidum figuratorum, a potiori
insectiformium prodigiosis imaginibus exornatae, specimen
primum/* written by Dr. Beringer and published in Wiirtz-
burg in 1726. Prof. Kemp summarized the work of the
author in attempting to explain a great collection of pseudo-
fossils from a theological standpoint, the fossils having pre-
viously been made by some practical jokers and buried in
the rocks for the author to find. Richard E, Dodge, Secretary.
Prof. Wilbur C. Knjght of the University of Wyo-
ming, at Laramie, has been appointed state geologist of
Wyoming.
Geological Society of Washington. At the meeting
of February 9th, the following papers were presented:
Remarks on the classification of igneous rocks. H. \V, Turner.
202 The American Geologist March, iws
The Briceville and Wartburg folios. Arthur Keith.
Notes on the Sierra Madre near Monterey, Mexico, R. T. Hill and
Bailey Willis.
Some strati^aphic changes in the New River coal fields. W. C.
Mendenhall.
At the meeting of Feb. 23rd the following papers were
presented:
Tertiary of South Dakota and Nebraska. N. H. Darton.
The origin of the Yosemite valley, California. H. W. Turner.
The Science Series is the title of a new series of scien-
tific books to be issued by G. P. Putnam's Sons. The series
is to be edited by Prof. J. McKeen Catteli, of Columbia Uni-
versity, with the co-operation of Frank Evers Beddard, F. R.
S. The following geological volumes are expected among
the earlier ones to be issued:
Earth structure. James Geikie,
Volcanoes. T. G. Barney.
Earthquakes. C. E. Dutton.
Physiography: The forms of the land. W. M. Davis.
Mr. J. Edward Sfurr, who has been spending several
months in geological study in Germany and more recentlx'
. in Paris, sailed for New York the last week in Februar\'.
Early in the spring he will go to Alaska, under the direction
of the United States Geological Survey, to investigate the
geology and ore deposits. of the Klondike region.
Mr. a. D. Roe, of Minneapolis, recording secretary
of the Minnesota Academy of Natural Sciences, has been
placed in charge of the scientific collections of the Acade-
my and is at present engaged in rearranging the important
paleontological and mineralogical collections. He has
placed on exhibition in the museum of the Academy a part
of his private mineral collection.
Prof. John Milne has received grant No. 81 from the
'^Elizabeth Thompson Science Fund.*' The amount of the
grant is $250 and it is given to aid in a seismic survey of the
world.
The Amehii-an (iEoLoaiST, Vol. XXt.
'■f»
IHE
AMERICAN GEOLOGIST,
Vol. XXI. APRIL, 1898. No. 4
AN OCCURRENCE OF ACID PEGMATYTE
IN DIABASE.
By T. A. Jaooab, Jr., Cambridipe, Mass.
(Plate XIV.)
The presence of quartz and acid feldspar in diabase, as
primary constituents, has been frequently described,* and the
primary nature of the minerals is said to be demonstrated by
jLi^ranophyric intergrowths of quartz with feldspar,t and by the
occurrence of quartz in idiomorphic phenocrysts.t Torne-
bohm's Swedish type§ is described as containing, in the inter-
spaces of the plagioclose laths, an intergrowth like graphic gran-
ite, consisting of parallel groups of quartz needles in colorless
feldspar. Rosenbuschj| has mentioned the remarkable abund-
ance of this so-called Konga type of diabase, occurring in many
parts of the world, characterized invariably by * 'quartz-feld-
spar aggregates in most delicate granophyric intergrowth,
such as is observed elsewhere only in granite-porphyry and
quartz-porphyry." Rosenbusch states, however, that the dis-
crimination of primary and secondary quartz is very difficult,
and that, in diabase, it is more frequently secondary.
♦Zirkel, Lehrbach der Petrographie, 1894, p. 631.
tRosenbusch, Mikros. Physiographic, 1896, vol. II. p. 11 11.
Zirkel, loc, cit.
Harker, Petrology for Students, 1895, pp. 109-110.
t Zirkel, loc. cit.
§N. Jahrb. f. Min., 1887, p. 258.
liOp. cit, p. 1 144.
204 The American Geologist, April. w»>
The writer has recently studied in detail the fragmental
inclusions contained in many of the dikes of the Boston basin.
Such inclusions of mineral substance, foreign to the matrix in
which they are now embedded, frequently serve as excellent
data for recording diflFerential movement or process, affording
a unit for comparison of the effects of secondary action which
might otherwise be unrecorded in a homogeneous eruptive
mass. The evidence, from inclusions, for the secondary or-
igin of the micropegmatyte in the Medford "quartz-diabase"
forms the subject of the present paper.
The Medford diabase has been described by Wadsworth,*
Crosby,t Hobbst and Merrill.§ The rock extends as a broad
dike from Somerville, northeast of Boston, Mass., through
Medford, the next township to the north, for a distance of over
three miles. In Medford it appears as a dike of width varying
up to a maximum of several hundred feet; about the old Powder
house, further south, in Somerville, the rock occurs again,
immediately in the strike of the Medford dike, but of unknown
form or extent to the southeast; in this direction it is found
again on Granite street in Somerville, not, however, in the
Medford trend and again of unknown boundary. In Somer-
ville the diabase is intrusive through the compact pelyte which
forms the chief northern member of the Boston basin sedi-
mentaries; to the north the dike cuts the older complex of
granite, dioryte, quartzyte and felsitic flows and tuffs.
Hobbs has described this rock as a diabase with an augite-
dioryte facics; the latter occurs only in the outcrops about
the Powder house and Willow avenue. Coarse ophitic ande-
sine feldspars, with the triangular interspaces filled with aug-
ite, biotite, large apatite crystals, the ores and a host of sec-
ondary minerals, make up the normal diabase. The speci-
mens of the dioryte facies from Willow avenue which we have
studied diflPer from the description given by Hobbs in the
large proportion of chloritized biotite and the absence of rec-
ognizable augite. The hornblende is in large, deep brown,
♦Proc. Bost. Soc, vol. XIX, 1877, P. 217.
tGeology of Eastern Mass, Occasional papers of Bost. Soc. Nat
Hist, 1880.
JBull. Mus. Comp. Zoo!., vol. XVI, no. i, 1888.
§BulI. Geol. Soc. Amer., vol. VII, p. 349-
Acid Pegmatyte in Diabase,— J aggar, 205
idioniorphic crystals ; the biotite shows idiomorphic hexagonal
basal sections, in some cases with a beautiful sagenite web.
The long magnetite crystal groups, resembling single straight
prisms, mostly on the border of chloritized hornblende, are
remarkable; they have frequently a length of from 0.75 to i.o
mm. and suggest the paramorphic resorption borders of the
hornblende crystals in trachytes and andesytes, but in this
case they never completely surround a crystal, and also occur
frequently in long needles between the feldspar laths; in one
case one of these long ore needles was seen to intersect a large
apatite crystal. Pyrite occurs, and secondary infiltrations of
quartz, epidote and idiomorphic calcite occur in irregularly
bounded masses in the thin section, stringing out into fissure
fillings among the larger minerals. The feldspars are more
basic tlian in the diabase facies, giving in one case symmetrical
extinction 19° and 12° in the zone normal to M; this would
make the feldspar near to Abi Ani, an acid labra(}orite .
We have thus three facies of this rock in Somerville.
(i) Augite — biotite — andesine diabase.
(2) Hornblende — augite — labradorite dioryte (Hobbs).
(3) Hornblende — biotite — acid labradorite dioryte.
In addition a drusy quartz-microcline pegmatite is a com-
mon feature in the Granite street and Pine hill (Medford) lo-
calities; this occurs in irregular lenticular or vein-like masses
merging into the normal diabase by gradual transitions. Ap-
proaching one of these veins, the long white plagioclase crys-
tals of the diabase are seen to acquire a salmon-colored bor-
der zone of more acid feldspar ; gradually the plagioclase gives
place to nricrocline and the long laths are replaced by short
rectangular pink prisms; quartz replaces all the bisilicates
and in places the rock appears like a granite; in the open
druses prismatic milky vein quartz overlying short, well-
formed microcline crystals, with in some places a green amphi-
bole and considerable calcite, stand out on the walls, having
all the appearance of infiltration products. Webster, in 1825,
noted the presence of quartz and a granitic feldspar as abnor-
mal, saying **in some parts of the bed the feldspar predomi-
nates and has a fine flesh color; in one place the prisms of feld-
spar are an inch or more in length, and cross each other in all
directions, leaving angular spaces '^ '•'. * which contain,
2o6 The American Geologist April, l89^
rarely, distinct crystals of quartz. * * ♦ Th^ sienitic
greenstone" (pegmatyte) "is crossed in various directions by
fissures, the walls of some of which are encrusted with thin
layers of feldspar: others are filled up with this mineral."*
These fine veins of microcline and quartz are abundant on
the west wall of the Granite street quarry near its northwest
corner, where occurs also a large mass about six feet in width
of coarse drusy rock, showing long feldspar laths an inch
or more in length, usually with a triangular arrangement, the
interspaces being filled with quartz and chloritic substance.
The contact of this mass with the finer grained diabase is
quite sharply marked in sinuous curves; in the diabase dark
mica and pink feldspar are very abundantly developed near
the contact. This mass seems to have been a more coarsely
crystalline gabbroid segregation in the original diabase, in
which the coarser quality of the miarolytic pores permitted in-
filtration of the pegmatyte-forming fluids more freely. The
drusy cavities now developed by weathering are frequently
from one to two inches in length, and contain crystals of
microcline feldspar, quartz and amphibole.
Similar drusy openings are found in the pegmatyte veins
which penetrate the normal diabase; and the walls of these
veins are not sharply marked, for we find the feldspars of the
diabase kaolinized and salmon-colored in the zone next to the
pegmatyte, showing by their wavy extinctions in thin section
an acid border on the side next to the triangular interspaces.
Still nearer to the vein the ophitic structure of the diabase
gives place to the development of plump squarish microcline
crystals irregularly distributed, with occasional quartz. A
series of three thin sections, made from a single specimen of
the rock at distances of lo cm., 4 cm., and o cm. from a quartz-
microcline druse, shows the transition from the normal dia-
base structure through the "quartz-diabase" phase to a normal
vein pegmatyte. In some cases the "quartz-diabase" zone is
much wider, the rock showing for several feet a considerable
amount of interstitial quartz, always, however, accompanied
by more or less of the salmon-colored feldspar. In these lo-
calities there is no immediate evidence, in either the hand
♦Boston Journal of Philosophy and Arts, 1825, vol. II, p. 277; and
vol. Ill, p. 486.
Acid Pegmatyte in Diabase.— Jaggar, 207
specimen or the thin section, of the secondary nature of the
quartz.
Large inclusions of quartz, of irregular clastic form, are
common in the Pine hill and Granite street outcrops. These
fragments vary in size from a few inches to a foot or more in
diameter; they frequently have a faint rose color; in some
cases they are coarse vein quartz, in others quartzyte. They
have not been found by the writer in the dioryte facies of the
rock which occurs in the vicinity of the Powder house. . These
inclusions are frequently rounded and sometimes embayed by
magmatic corrosion ; one of these is now well displayed on the
west wall of the Granite street quarry, measuring twelve by
three inches, with rounded contours bounded by the wreath of
augite prisms characteristic of quartz inclusions in basalt,* and
with a narrow-necked embayment at one end three inches in
depth.
The augite wreath, or more accurately, mantle, invariably
encases these inclusions, forming in the thin section an endo-
morphic "reaction rim*' in the diabase at the contact of the
inclusion. This mantle varies with the association in the dia-
base; if in association with the quartz-pegmatytes the rim is
wide, showing successive zones from the diabase to the in-
clusion of augite, microcline, micropegmatyte and chlorite;
if in the normal diabase the rim is a simple border of augite
prisms.
Thin sections (52-53) from the contact of a large quartz
inclusion in the normal diabase at Granite street show coarse
ophitic structure in the diabase, with biotite, augite and some
brown hornblende. The quartz of the inclusion is clear, con-
sisting of very large interlocking grains which show strain,
with numerous liquid inclusions in lines; it is apparently vein
or pegmatyte quartz. The border outline of the quartz ap-
pears corroded and irregular, with long prisms of a green
amphibole and chlorite penetrating it in places, and abundant
calcite. Between this border and the diabase, closely packed
augite prisms form a continuous zone, idiomorphically ter-
minated on the diabase side, their bases on the inclusion side
♦Dannenberg, A. — Tschermaks Min. u. Pet. Mitth., 1894, Bd. XIV,
p. 17.
Lncroix, A. Les enclaves des roches volcaniques, 1893, p. 585.
Vide also Rosenbusch, p. 1034. Zirkel, vol. II, p. 871; vol. Ill, p. 102.
2i6 TJte American Geologist. April, imi^h
Hormistonlahti, the total thickness of the formation of the
schists of Tammerfors is at least from four to five thousand
metres (2,000 metres of phyllytes, 1,500 metres of the lower
tuffs, and of the conglomeratic zone, and the remainder upper
tuffs, with their intercalations of phyllyte and conglomerate).
The order of this enumeration is also that of their stratigraphic
succession, the phyllyte always outcropping alongside of the
gneisses which supported it formerly, and these last south of
the schists.
The great contrast between the straight stratification of
the phyllytes and the intense folding of the gneiss warrants the
presumption of a great hiatus between these formations. In-
deed, at several points, as at the north of Aittolahti, can be
seen dikes of granite which are abundant in the gneiss, which
never cross the phyllytes. There can be seen, in the neighbor-
hood of the contact line, only small masses of porphyritic
granite introduced in a solid state during the folding of the
phyllytes, but never anything that can be interpreted as an
injection of this rock when in the condition of a magma.
In the region to the east from Nasijarvi, north from Siuro
and in the country west of Paijanne, can be seen the clear con-
tact between the phyllytes and the porphyroidal granite. It is
there easy to see that the granite has served as a base for the
metamorphosed sediments which constitute the formation of
the schists of Tammerfors.
The granite which outcrops north of the schists shows al-
ways contact phenomena that indicate its more recent date.
It cuts the schists in numerous dikes, and the manner of pen-
etration is so intimate that over several hundreds of metres the
contact rock can be called gneiss in the form of dikes or gran-
itized schist. One can very easily study the origination of
such a rock on the w^est shore of the Nasijarvi, at the northern
contact of the outcrop of the schists of Tammerfors. On the
eastern shore, where can be seen analogous phenomena, the
porphyroid, rich in uraHte, appears to be converted into a
massive rock resembling a dioryte. In another contact zone,
at Orihvesi, the schists are changed, for a distance of more
than a kilometre from the line of contact, into a schistose rock
resembling a leptynyte rich in feldspar, which appears to have
crystallized under the influence of the surrounding:,^ granite.
Geology of Tammerfors. — Seder/iolm. 2 1 J
This granite also shows a zone of endogenous contact, in the
form of a structure at once porphyritic and evidently micro-
pegmatitic, although in part concealed by the metamorphism
which the rock has suffered since consolidation.
The granite contains, at several points, elongated bands
of schists, and everywhere very numerous fragments. These
inclosures are in general strongly granitized, and in that case
they have the structure of a dike gneiss (''gneiss a filons"),
or of a dioryte. But these enclosures show also, here and
there, the structure and the mineralogic composition of the
schists of Tammerfors, and contain sometimes undoubted
pebbles, which are incontestable proof of the sedimentary
origin of the enclosed fragments. Quite often, as for exam-
ple, north of Teiskola, these enclosures have an aspect of a
true dioryte, though of a variable structure.
The schists which outcrop in the parishes of Suodenniemi
and Lavia at the west of Tammerfors are in part more meta-
morphosed than those of which we have just spoken. Phyllyte
is here often replaced by mica schist which only differs very
little in its petrographic composition from the mica schists of
the underlying formation. Here also is a conglomerate which
has almost the aspect of a gneiss spotted with amphibole. At
Harju, in the parish of Suodenniemi, is another very interest-
ing conglomerate, on account of its almost gneissic structure.
On the surface which is attacked by the atmosphere, the con-
tours of the pebbles and their rounded forms appear very dis-
tinctly, but in the hand specimens, and especially in thin sec-
tions, their limits are confused in consequence of the presence
of numerous secondary minerals. Everywhere one can recog-
nize among the pebbles representatives of some of the rocks
that occur in the underlying gneiss, among others of the
* 'gneiss of Lavia." This porphyroidal schistose rock recalls,
when it is well preserved, a tuff or a porphyritic effusive r(j(ck
which by a profound metamorphism has been made to take
the aspect of a gneiss.
It is very interesting to see here the most positive demon-
stration of a discordance between the Bothnian schists of
Lavia and the mica schists of the underlying formation which
possess almost the same petro^^raphic characters. At Lavia, in-
deed, can be seen the clear contact of the granite cutting the
210 The America7i Geologist. ♦ April, i89si
(loo). The dichroism mentioned by Hobbs* as character-
istic of the augite of the diabase could not be detected in these
bands. The chief alteration product on the cleavage cracks
is chlorite; in several places a deep green amphibole was also
observed, in well marked basal sections, and without fibrous
structure. It seems probable that the formation of this
mineral was associated with the same process that produced
the inner zones, next to be described.
THE ZONE OF POTASH FELDSPARS, (F.) Next
to the augite wreath, on the inner side, is a row of squarish
crystals of microcline, developed base to base with the prisms
of the augite zone, in bunches idiomorphically terminated on
the proximal side. (See figure i.) In two cases the character-
istic microcline twinning is very plainly shown, though as the
section is cut transverse to the surface on which the crystals
developed, the basal section, which would show plainly the
grating structure, is rare. The M sections are common, and
in one case the extinction is 5**, with no twinning visible. The
section nearest to the basal gives an extinction of 12° on one
lamella of the albite twinning and about 17° on the other; the
pericline lamellae are indistinct and show that the section is
obliquely oriented, but the grating-structure is typical.
Furthermore, these feldspars are very largely kaolinized, the
opaque portions showing in reflected light the characteristic
salmon color.
THE ZONE OF MICROPEGMATYTE, (M.) Within
this band of microcline is a zone of varying width consisting
of quartz individuals filled with a very remarkable micropcg-
matyte intergrowth with the kaolinized feldspar; the latter
forms feather and fern-like structures of most delicate and in-
tricate patterns, sometimes anastomosing, sometimes enclos-
ing minute triangular portions of the quartz, and in other cases
with the usual microgranitic habit. A portion of this struc-
ture is shown in the accompanying microphotograph (figure
2) magnified 60 diameters, in ordinary light; the light portions
are quartz, the dark are kaolinized feldspar.
In association with this, and nearer the quartz border, cal-
cite and chlorite are abundant, the latter sending long fibrous
bundles into the crevices of the quartz (Q), the border of
♦Op. cit, p. 6.
Acid Pegmatyte in Diabase,— Jaggar, 21 1
which is corroded and embayed. The quartz inclusion is
made up of large interlocking individual grains of varying
size.
Summarizing the description of the cross-section of the
reaction rim about the inclusion, we have an outer zone of
augite prisms as is usual about quartz inclusions in basalt, and
as in most cases in this diabase. But within this is a zone of
quartz- microcline pegmatyte, of exactly the same nature as
that which fills the cavities in the adjoining rock; and the
microcline is developed as a zone of prisms on the inner sur-
face of the old augite zone while the border of the quartz in-
clusion is corroded, — phenomena that can be accounted for
only on the hypothesis that the waters or vapors charged with
the pegmatyte minerals forced their way through the pores
<-iX the old augite zone, which was not chemically affected by
them. The quartz inclusion they corroded, however, and sim-
ultaneously microcline was deposited on the inner surface of
the augite mantle, and last of all the micropegmatyte mixture.
An inner zone of acid feldspar about a quartz inclusion
has been described by Dannenberg* in basalts of the Sie-
bengebirge, and his succession of zones closely resembles that
of the Medford diabase. He notes next w^ithin the augite
zone a band of large fan-shaped bundles of feldspars of higher
acidity than the feldspar of the basalt, but he does not state
whether these are developed radial to the inner surface of the
augite mantle or to the quartz surface. He notes an inner or
second augite zone with prevalent skeletal structures; this
we have also observed occasionally.
Mention was made in a preceding paragraph of the infil-
tration minerals observed in the thin section of the diorite
facies of the rock. Merrill f has called attention to the extra-
ordinary depth to which the post-glacial disintegration of this
rock has gone, largely due "to its coarse and somewhat granu-
lar structure;" it is highly miarolytic, the ophitic framework
of feldspars forms a sort of "sponge" support when much
degeneration has gone on in the interspaces. Just as such a
♦Danneberg, A., Studien an Einschliissen in den Vulkanischen Ges-
teinen des Siebcngebirges, Tschermaks Min. u. Pet. Mittheilungen.
J894, Bd. XIV, p. 17.
tBull. Geol. Soc. Amer., vol. VII, pp. 349-362, 1896.
212 The American Geologist. April, isftj
structure permits deep penetration of waters from the surface,
so it affords easy passage to heated "mineralizers" from below,
and the evidence from the pegmatytes in question shows dis-
tinctly that they were formed by secondary infiltration.
If this be true of the case in question, however, we should
expect to find similar pegmatyte dikes cutting rocks in the
vicinity other than the diabase. Such evidence is not want-
ing; three miles to the westward the long ridge of Arlington
heights, extending to the southward, is composed chiefly of a
coarse hornblende-biotite-diortyte associated with an ancient
amphibolite gneiss. Outcrops of the gneiss occur just west
of the southern end of this ridge at Owl hill, and at numerous
points along its flanks, notably in the region immediately ad-
jacent to Spy pond on the northwest Here the gneiss is in-
terbedded with black calcareous strata and the whole series
strikes northeast with a northwest dip of 40°. Intrusions of
granite interrupt the gneissic rocks, appearing in one place
like an irregular interbedded sheet or laccolyte; the gneiss is
seen to dip directly under a granite mass. Cutting both the
gneiss and the granite are pegmatyte dikes of coarse, granular
quartz and large salmon-colored microcline crystals. Trans-
verse to the plane of the wall, one of these dikes showed a
remarkable parting, similar to columnar structure, in the
quartz; the quartz could be broken out in rectangular blocks.
As there is much evidence from thin sections that all of these
rocks have been violently strained dynamically, it is probable
that this jointage in the vein is due to pressure. These peg-
matytes, of which several dikes were found, trend east and
west as do also the basic dikes observed in the same vicinity.
Minute veinlets of epidote occur in the pegmatyte, and epidote
occurs in large idiomorphic crystals in both the granite of
Arlington and the dioryte of Owl hill, conspicuously in the
latter.
These granites and diorytes are usually believed to be very
ancient rocks, and so indeed they may be. The pegmatyte
dikes cutting them, however, are identical in composition and
microscopical structures w^th those cutting the Medford dia-
base, and the two sets are believed by the writer to be of con-
temporaneous origin. That this period followed closely on
the intrusion of the granites is not probable in this case, and
Geology of Ta?nmetfors. — Sederhobn. 2 1
->
we do not believe that these pegmatytes bear the same rela-
tion to the granite that is usually attributed to the aplyte and
lamprophyre dikes which represent the last differentiation
products of the granite magma. The word "dike" here used
for these pegmatytes is perhaps inaccurate if used in the
genetic sense of an igneous intrusion. The pegmatytes cut-
ting the gneiss are more like quartz-feMspar "veins," varying
from a few inches to two feet in width, sometimes drusy, show-
ing idiomorphic terminations to the crystals in open cavities,
sometimes an aggregate of granular quartz with very little
of the feldspar. Elsewhere the "graphic granite" structure
predominates. Were it not for these feldspathic intergrowths,
the word "vein" would both here and in the intrusions in the
diabase seem more appropriate. In both cases it is believed
that the deposits were made from super-heated waters under
pressure, which took into solution from the rocks through
which they passed (probably largely granite) the necessary
mineral matter. The period at which this took place was after
the consolidation of the Medford diabase intrusions, probably
post-Mesozoic. This is proven by the zonar growth of the
feldspars of the so-called quartz-diabase, by the pegmatyte
veinlets and by the secondary pegmatyte bands surrounding
the quartz inclusions. We thus conclude that granophyric in-
tergrowth of quartz and feldspar in a diabase is not necessarily
evidence of the primary nature of these minerals.
THE GEOLOGY OF THE ENVIRONS
OF TAMMERFORS.
By J. J. S^DEBHOLM.
[Translated from the Guide to the excursions of tliu Seventh International Con-
fcress of Geologists.]
The Archean rocks of the environs of Tammerfors can
be divided into three parts which are as follows from above
downward.
1. Post-Bothnian granite.
2. Bothnian schists.
3. Pre- Bothnian terrane of gneiss.
In the last, granites, which are essentially ipetamorphic,
prevail, in part porphyroids, and foliated gneisses which are
214 The American Geologist, April. i8»<
granetised mica schists, folded to the highest degree. There
are also typical mica schists, and, in the granites, inclusions of
dioryte and peridotyte.
All these rocks appear at the south of the city of Tammer-
fors in a belt, sometimes having the width of 40-60 kilometres,
extending toward the west to the gulf of Bothnia, and toward
the east beyond the lake Paijanne. The same formation
is also very extensive in other parts of the country.
To the north from this belt of strongly metamorphic rocks
come in the schists of Tammerfors, or Bothnian " formations.
They are in bands extending from west to east and generally
following the borders of the gneiss formation and the great
area of post-Bothnian granite which extends from the gneisses
toward the north covering an area of more than 23,000 square
kilometres . The layers of these schists are always nearly
vertical.
These schists are remarkable for their character, which is
at once crystalline and completely detrital. They are often
represented by typical phyllytes which sometimes approach
argill)rtes and sometimes pass into fine-grained mica schists,
often containing feldspar. In this case they present a gneissic
character.
The phyllytes of Nasijarvi show, by their very distinct
stratification and their internal structure, that they are a for-
mation of shale in a metamorphic state, intercalated with thin
beds of an argillaceous sandstone (leptitic phyllyte). The
phyllytes often contain a carbonaceous substance, sometimes
accumulated in thin bands, the outlines of which suggest an
organic origin.
A very typical leptyte, of a reddish color and poor in
mica (always black mica), appears in a small area west from
Tammerfors. It shows a distinct alternation of beds orig-
inally horizontal, and of layers which possess an oblique strati-
fication.
Dark green schists, rich in amphibole (and most frequent-
ly in uralite), and in plagioclase which constitutes porphyritic
crystals, are almost as widely extended as the phyllytes. These
rocks, called porphyroids, are metamorphic tuffs of Archean
effusive rocks. In them are sometimes seen intercalated beds
of true eruptive rocks, notably uralite porphyrytes and plagio-
Geology of Tarmnerfors. — Sederholm, 215
clase and orthoclase porphyrytes, which in their original state
were identical with basalts and andesytes and with modern
trachytes. A similar porphyritic rock also crosses the phyl-
lytes in dikes.
The conglomerates with a crystalline cement are, how-
ever, the ones which among the Bothnian rocks afford the
highest interest. They consist of interbedded portions, and
here they are of greater amount than in any other system
equally old.
They can be studied best on the shores of lake Nasijarvi,
and especially in the little bay of Hormistonlahti, where can be
seen four vertical layers whose thicknesses are, respectively,
1-2 metres, 200-300 metres, and 20 metres. They can be fol-
lowed toward the east for more than 30 kilometres. West-
ward from Nasijarvi they recur for a distance of 4 kilometres
in the parish of Ylojarvi, and always at the same geological
horizon.
The pebbles of this Archean conglomerate are very varia-
ble as to size, the largest having a diameter of half a metre,
and the smallest being microscopic. They are generally well
rounded, and of different forms, according to their petro-
graphic nature. The greater part consist of different prophy-
ritic effusions, and of porph)Toids, phyllyte and leptyte, all
these rocks outcropping immediately to the south of the con-
glomerate. But there are found also two varieties of granite
or quartziferous syenyte, and a quartziferous dioryte.
The cement of the conglomerate is crystalline, but under
the microscope it shows an originally clastic character. It is
composed of minute fragments of the same rocks which form
the pebbles, itiixed with fragments of plagioclase, uralitized
augite, olivine changed to biotite, etc., and of secondary min-
erals, especially of feldspar, quartz and biotite. The beds of
conglomerate alternate with a dark-green schist very rich in
uralite, which is a metamorphic tuff of a basic effusive rock.
All these beds are vertical.
North from these beds of conglomerate are found, on
point Kameeniemi, a new conglon cratic bed, with a thick-
ness of 20 metres. If this bed, as well as the tuffs and phyllytes
that appear toward the north, were originally superposed con-
formably upon the rocks which outcrop to the south from
2i8 TJu American Geologist. April, \ms
schists of thegneissicterrane with the schists of Lavia. In the
contact zone the granite presents the character of a breccia
which near the schists, assumes the aspect of a basal con-
glomerate. Evidently the surface of the granite was disinte-
grated by atmospheric action before the deposition of the sedi-
ments which in a metamorphic condition, form now the schists
of Lavia and of Tammerfors. The same phenomenon is re-
peated at several places in the same region, though in
conditions less typical.
The mass of the schists in the west of Finland formed, like
the schists of the region of Tammerfors, in the interval be-
tween the two great Archean epochs of granitic irruption in
those countries, has received the name of the ''Bothnian for-
mations." To this series of rocks belong also the uralitic
porphyrytes of Tammela and of Kalvola at the west of Taves-
tehus, and of Pellinge near Borgo. The effusive character
of those Archean rocks, accompanied by tuffs, cannot be
mistaken. Further one can also refer here probably the schists
which outcrop at Ylivieska, in the government of Uleaborg,
and perhaps also several formations in northern Sweden. All
these schists, whose layers are always almost vertical, abound
in intercalations of conglomerates.
Again, in the neighboring portions of the coast of the gulf
of Finland, where the land is composed of Archean rocks of a
different age, dislocated at the same epoch and intimately pen-
etrated by post-Bothnian granites, can be found, at several
places, debris of Bothnian rocks the original composition of
which is sufficiently preserved to be recognized.
All this country having thus undergone intense disloca-
tions at an epoch later than the deposition of the Bothnian
beds, it is not possible to doubt their pre-Cambrian age, es-
pecially if one takes into consideration that the beds of Cam-
brian and Silurian rocks of Esthonia, on the opposite shore,
south of the same gulf, are almost horizontal. It is to be re-
marked also that the pre-Cambrian sandstones of Bjorneborg
and of Kauhajoki, and the granito-porphyritic rocks called
"rapakivi" which occur in very extensive ''massifs" in the
south of Finland, do not show any sign of metamorphism.
The pre-Cambrian age of the rocks mentioned being
proved by the fact that they have been recognized in the form
Drainage in the Adirondacks. — BrigJmm, 219
of pebbles in the basal fossiliferous conglomerate of the Cam-
brian, it is plain that the folding in this region was terminated
long before the Cambrian period.
But the age of the Bothnian schists seems to be susceptible
of a still more exact determination. In the eastern portion of
Finland is a series of folded sediments more ancient than the
"rapakivi," but more recent than the Archean granites of the
type of those which cut the schists of Tammerfors. Hence
the latter are separated from the base of the paleozoic group
by two great formations (of the systemic rank) and three im-
mense discordances.
They are, further, so intimately allied to the fundamental
crystalline complex, called Archean, of the south of Finland,
that it is absolutely impossible to hope to separate them from
it. Therefore, their presence at several points is not at all
surprising to those who have made investigations on this
tcrrane of such rocks, existing at other places. In all cases
the formation of Tammerfors is such that the sedimentarv and
the metamorphic nature of the true Archean schists is shown
with the most complete evidence.
NOTE ON TRELLISED DRAINAGE IN THE
ADIRONDACKS.
By Albert Pbbrt Bbioham, Hamilton, N. Y.
(Plate XV.)
This brief paper may serve to suggest a problem in Ad-
irondack drainage. In the study of the new topographic maps
of eastern New York attention was attracted to a marked ad-
justment of drainage in the region covered by the central and
western part of the Elizabethtown sheet and the eastern part
of the Mt. Marcy sheet. The district, as limited in the ac-
companying sketch map (plate XV) traced from the sheets,
extends fourteen miles from east to west and eleven miles
from north to south. Its eastern edge is from five to seven
miles west of lake Champlain and its western edge is four and
one-half miles from the summit of Mt. Marcy, the highest of
the Adirondack peaks. In the central and southeastern part
of the district the summits commonly range between 1,500
220 The American Geologist. April, v^t
and 2,000 feet in altitude. Farther north and west the higher
mountain mass is attained, and several summits exceed 4,000,
or even approach 5,000 feet.. It is an area of bold moun-
tains and deep valleys, with a steep general slope to the
southeast. The range of relief is from Dix Mt. 4,842 feet,
to the exit of the Boquet river, at about 625 feet. The moun-
tain ridges trend northeast by southwest and are seven or
eight in number, alternating with the principal valleys. Many
subordinate valleys cross these ridges at right angles, thus
dissecting the mass in a marked fashion into rectangular
blocks. The drainage of most of the area, and that chiefly
concerned, is divided between the Boquet river on the north
and the Schroon and its branches on the south. A corner at
the northwest lies in the basin of the Ausable, and a narrow
strip on the east drains into lake George.
The trellised arrangement of streams and valleys is ex-
plained ana the general principles are quite fully illustrated by
Prof. Davis, in his account of "The Rivers and Valleys of
Pennsylvania."* Willis, in his monograph on the northern
Appalachians, treats the subject briefly and gives a suggestive
sketch map.f Several atlas sheets of the Pennsylvania topo-
graphic map may also be consulted in this connection. J
The conditions apparently essential for such arrangements arc
a series of anticlinal and synclinal folds of alternating hard
and soft beds, with rising and falling axes. These conditions
are met whenever, over a considerable area, a normal series
of sedimentary beds is subjected to moderate folding. Lateral
migration along the soft outcrops, and capture by favorably
situated streams, will then produce the grapevine system. The
master streams may follow the axes after mature adjustment,
or in case of antecedent streams, or revival with different
attitude, they may cross the axes of folding.
Almost no study has been given to Adirondack drainage.
The direction of the mountain ridges is noted by Emmons
and others, and indeed is suggested by the alignment of the
lakes, upon an ordinary map. The most complete account
^National Geog. Mag., vol. I, pp. 206-219.
tNational Geog. Monographs, pp. 185-187.
tProf. R. E. Dodge, of the Teachers' College. New York, has
broiipht out this drainage system very effectively for class-room use
by n.ounting a group of sheets and tracing the streams in heavy lines.
>
a
o
3
a
»
o
D
»
3
B)
V)
m
X
O
c
3
z
•<
o
Pi
P3
OB
n
220 The American Geologist, April, i89:i
and 2,000 feet in altitude. Farther north and west the higher
mountain mass is attained, and several summits exceed 4,000,
or even approach 5,000 feet.. It is an area of bold moun-
tains and deep valleys, with a steep general slope to the
southeast. The range of relief is from Dix Mt. 4,842 feet,
to the exit of the Boquet river, at about 625 feet. The moun-
tain ridges trend northeast by southwest and are seven or
eight in number, alternating with the principal valleys. Many
subordinate valleys cross these ridges at right angles, thus
dissecting the mass in a marked fashion into rectangular
blocks. The drainage of most of the area, and that chiefly
concerned, is divided between the Boquet river on the north
and the Schroon and its branches on the south. A corner at
the northwest lies in the basin of the Ausable, and a narrow
strip on the east drains into lake George.
The trellised arrangement of streams and valleys is ex-
plained ana the general principles are quite fully illustrated by
Prof. Davis, in his account of "The Rivers and Valleys of
Pennsylvania."* Willis, in his monograph on the northern
Appalachians, treats the subject briefly and gives a suggestive
sketch map.f Several atlas sheets of the Pennsylvania topo-
graphic map may also be consulted in this connection.^
The conditions apparently essential for such arrangements are
a series of anticlinal and synclinal folds of alternating hard
and soft beds, with rising and falling axes. These conditions
are met whenever, over a considerable area, a normal series
of sedimentary beds is subjected to moderate folding. Lateral
migration along the soft outcrops, and capture by favorably
situated streams, will then produce the grapevine system. The
master streams may follow the axes after mature adjustment,
or in case of antecedent streams, or revival with different
attitude, they may cross the axes of folding.
Almost no study has been given to Adirondack drainage.
The direction of the mountain ridges is noted by Emmons
and others, and indeed is suggested by the alignment of the
lakes, upon an ordinary map. The most complete account
♦National Geog. Mag., vol. I, pp. 206-219.
tNational Geog. Monographs, pp. 185-187.
JProf. R. E. Dodge, of the Teachers' College, New York, has
broiipht out this drainage system very effectively for class-room use
by mounting a group of sheets and tracing the streams in heavy lines.
Drainage in the Adirondacks. — Brighatn. 221
of the geology of this part of the Adirondacks is by Prof. '
Kemp,* who, in his introduction, gives an outline of tfie
topography and supports with a number of considerations the
view that the valleys are mainly due to the faults and that
the mountain ridges are of the block-tilted type, though this
is affirmed to be less readily demonstrable in massive and
metamorphic rocks. This increases the interest and the
perplexity of the problem, and will make the more welcome
to physiographers the structural facts which Prof. Kemp and
others are working out in the Adirondack region. The drain-
age is also very ancient, hence through oscillation and the
baselevelling processes there may have been several oppor-
tunities for new adjustments, but through all it would appear
that the original streams consequent on folds or faults of
northeast by southwest trend have transmitted their axial
direction to their successors. If the region has ever been
baselevelled and the drainage revived, the elevation was not
accompanied by tilting of such a nature as to send the master
streams across the great structural lines. All goes to empha-
size the suggestion of Prof. Davis that "every case must there-
fore be examined for itself before the kind of re-arrange-
ment that may be expected, or that may have already taken
place, can be discovered."
It remains to note a few features shown by the sketch
map. The south fork of the Boquet river, flowing northeast,
makes two distinct elbow turns, first to the southeast and
then resumes its original direction to the northeast, in the
main valley. The extreme head waters of Lindsay brook
show a tendency to open up the Boquet valley farther to the
southeast. The north fork of the Boquet occupies another
parallel valley two miles northwest of the south fork. This
stream makes three elbows, first to a valley in line with south
fork, then to the main valley. In the case both of the Boquet
and the Schroon, tributaries flowing to the southeast are con-
spicuously longer than those flowing northwest. This is
readily explained by the steep southeastward inclination of the
country and the consequent rapid headward cutting of the
tributaries flowing from the northwest. Similar features in
♦Preliminary report on the geology of Essex county, 47th Report
\ew York State Museum, 1894.
222 The American Geologist. AprU. ifc98
the Schroon drainage will be readily suggested by inspection
of ihe map. The sharp elbows and rectangular blocks are
even more conspicuous upon the contoured sheet than in the
accompanying map. The valley of New pond is practically
continuous with that occupied by the upper transverse tribu-
taries of Lindsay and West Mill brooks, and with the valley
of Niagara brook. In a similar way the valley of Ash Craft
brook continues southwest to Lindsay brook. Mill brook
and Newport brook show a similar alignment with each other.
It is quite possible that the Boquet has robbed some territory
from the Schroon, because of its much more rapid descent and
much shorter distance to the baselevel.
If the northeast southwest valleys are due to faulting, the
long, intervening mountain blocks may have been cut up into
short rectangles chiefly by the northwest heading of trans-
verse streams as above described. This work seems to have
diverted and checked the growth of some streams along the
great structural lines. Old as the region is, adjustment ap-
pears to be by no means complete.
SOME RESEMBLANCES BETWEEN THE ARCHEAN
OF MINNESOTA AND OF FINLAND.*
By \. H. WiNCHELL, Minneapolis.
In several of the reports of the Minnesota Survey some
characters of the Archean have been described which have ap-
peared to be unique, since they have not been mentioned else-
where in the lake Superior region. The non-observance of
these characters by other geologists has rendered it necessary
to be cautious in drawing final conclusions as to their origin
and significance. Hence some of the interesting localities
have been examined several times, and additional details and
sometimes new interpretations and new facts bearing on the
genesis and succession of some of the parts of the Archean
have been derived from these later visits.
It was during the latter part of the summer of 1897 that
♦Read before the Minnesota Academy of Natural Sciences, Dec. 30th,
1897.
Archean of Minnesota and Finland. — WitichelL 223
some of the most important observations were made. * With-
out attempting here to give in extenso the evidence of the con-
clusions arrived at , the following general scheme will show
the Archean formations which exist in the northeastern part
of the state and their order from above downward, accord-
ing to all the facts now at hand. These parts are represented
by hundreds of specimens collected, and by hundreds of mi-
croscopic thin sections.
In descending order:
1, Granitic intrusion^ cutting and metamorphosing the
earlier schists and fragmentals. This granite, though gener-
ally massive and having a distinct irruptive contact on the
older rocks, is also sometimes gneissic, and the schists vary to
a banded gneiss, so that in some cases the transition from the
one to the other is screened by these similarities and is hardly
noticeable. This rock is seen about Snowbank lake and
Moose lake, about the western confines of Disappointment
lake and at Kekequabic lake. It is also supposed to constitute
the Giant's range. It is a wide-spread, irruptive granite, is
coarse-textured and fresh.
2. Upper Keewatin. Consists of conglomerate (at Stuntz
island and at Saganaga and Ogishke Muncie lakes), sericitic
schists, quartzose and also micaceous schists, graywackes,
clay slates, chloritic schists and porphyroids. •Of these rockb
which stand about vertical and are distinctly bedded by sedi-
mentary action, the conglomerates are the most remarkable,
for they seem to pervade the formation at different horizons,
and by metamorphism they acquire coarse secondary feldspar
and hornblende crystals. The whole formation becomes
changed, by the widespread effect of the pressure and dis-
turbance coincident with the intrusion of the granite above,
into mica schists and banded gneisses, and is penetrated by
many granitic dikes. Such mica schists, embracing many
conspicuous boulder-forms on the weathered surfaces, are to
be seen about Moose lake and between there and Snowbank
lake, and on the western shores of Snowbank lake; about Dis-
appointment lake, Kekequabic lake and eastward to Zeta lake.
These fragmentals are conspicuously porphyritic by secondary
*In this trip I was accompanied by Dr. U. S. Grant and by Mr. A. H.
Klftnian.
224 The American Geologist April, ishs
feldspars between Moose and Snowbank lakes, and at Zeta
lake.
3. Granitic intrusion. This intrusion is frequently char-
acterized by fine-grained granites or felsytes, but is chiefly rep-
resented by the granite of Saganaga lake, which is frequently
very coarse. The Upper Keewatin lies unconformably upon
it at Saganaga lake, with a profound erosion interval between,
but this granite cuts older greenstones and green schists (No.
4) at West Seagull lake. Such granite is seen at Ely (a little
west of the village) in the form of a light-colored felsitic dike
or quartz porphyry, which can be traced for a quarter of a
mile east and west. It also occurs on the Kawishiwi river. It
supplied numerous boulders for the conglomerates seen in the
Upper Keewatin.
4. The Kawishiivin or Lower Keewatin. This is the old-
est known formation in the state,* and is essentially a .green-
stone formation, in which the rock is both massive and frag-
mental. When stratified, as it is over large areas, it consists
of basic tuffs, agglomerates and green, stratified schists and
j^reenwackes. It contains the banded jaspilytcs and iron ores
at Vermilion lake. At Moose lake is a jaspilyte iron ore
which is at the same time a coarse conglomerate, but it is not
certain that this is in the Lower Keewatin. These green-
stones, with their attendant schists and jaspilytes and green-
wackes, are cut extensively by granite, and by quartz-porphy-
ries, as above mentioned, and are converted to mica schist
and banded gneiss, and in that form are very widely extended.
There is frequently considerable doubt whether some of the
Minnesota areas of gneiss and mica schist (Coutchiching?)
belong to the Upper or to the Lower Keewatin.
No account is here taken of the diabase dikes, whether
Keweenawan or earlier, which are not uncommon.
Unconformably above all these is the Animikie formation,
ot the age of the Taconic, the base of the Paleozoic. This
formation is tilted but not closely folded. It contains the
iron ores of the Mesabi range, as well as those of the Penokee
and, when broken and overwhelmed by the Norian, it wit-
nessed another, but less extensive, granitic intrusion.
♦In a former scheme of the structure of the Archean this was put at
the top of the Keewatin (20th re[)ort, p. 4.) but later field observations
have shown it is the oldest known rock terrane of the state.
Archean of Minnesota and Finland. — WinchelL 225
To recapitulate briefly, the descending order of the parts
of the Archean seems to be as follows :
1. Granitic protrusion and extended metamorphism of the
elastics.
2. Upper Keewatin. When not metamorphosed these are
conglomerates, gray wackes and clay slates, sometimes min-
gled with greenish debris.
3. Granitic intrusion, the intrusive rock being usually
fine-grained, but also constituting coarse granite.
4. Lower Keewatin or Kawishiwin, mainly greenstones,
both massive and fragmental.
From this it appears that some order is beginning to ap-
pear in that ancient group of rocks which for many years geo-
logists have been content to designate simply as Archean or
as the fundamental complex.
For a knowledge of the results obtained by similar studies
in Finland we are indebted to the Guide-book of the Inter-
national Congress of Geologists of the seventh session, in
which the government geologist, J. J. Sederholm, gives a suc-
cinct description.* A condensed statement of the structure
and stratification of the Finland Archean, as given by Seder-
holm, is as follows rf
In descending order:
1. Post-Bothnian granite.
2. Bothnian schists.
3. Pre-Bothnian terrane of gneiss.
At the bottom of the known Archean (No. 3 pre-Both-
nian gneiss) there is therefore, as further described by Seder-
holm, a series essentially gneissic but containing mica schists,
and porphyroids. These schists and porphyroids, on the as-
sumption that they are metamorphic fragmentals, imply the
existence of some older rocks from which the debris was de-
rived. What the nature of that older rock may have been is
not stated definitely by Sederholm, but it is possible to infer
from inclusions which he mentions in the granites that pierce
these schists that it was a basic rock. Such inclusions are
♦Reference may be made to a letter from Dr. Bascom in the Ameri
CAN Geologist, Nov. 1897, p. 339, in which is described the excursion to
Finland, with notes on the geology.
■fA translation of Sederholm's description of thise formations is gi\en
in this number of the American GEOLO(ii«T.
226 The Ante f lean Geologist. April, 18O8
stated to consist of dioryte and peridotyte. This pre-Both-
nian gneiss and the schists which accompany it are com-
parable to the gneiss and schists of the Lower Keewatin when
crystalline, to which Lawson gave, in part at least, the name
Coutchiching, and the intersecting granites when intrusive to
the earliest Minnesota granites.
To the north from this belt of strongly metamorphic and
highly folded rocks is a great, formation which Sederholm has
named the schists of Tammerfors, or the Bothnian formation,
which lies in discordance of stratification on the foregoing.
This consists of detrital matter, showing distinct sedimentary
structure, and developing a thickness of four to five thousand
metres. Its beds are nearly or quite vertical, and while
plainly of fragmental nature they are also distinctly crystalline.
They are phyllytes which approach argillytes and sometimes
pass into a fine-grained mica schist, and when they contain
feldspar they present a gneissic character. But the most re-
markable feature of the Bothnian formation is the prevalence
of conglomerates. The pebbles vary from microscopic j^^rains
to half a metre in diameter. They are well rounded, the
greater part consisting of different porphyritic effusives, but
there are also pebbles of porphyroids, phyllyte and leptyte.
This conglomerate has a crystalline cement, and, along with
the phyllytes it is converted into mica schists. The forms of
the boulders are most distinctly outlined on weathered sur-
faces, but when freshly broken they are so intimately blended
with the cement that it is impossible to distinguish their limits;
except that, frequently, the secondary feldspars are more pro-
fusely or more sparingly developed in the boulders than in the
rest of the rock surrounding. The beds of conglomerate al-
ternate with a dark green schist, which, according to Seder-
holm, is a metamorphic volcanic tuff, cotemporary with
the conglomerates. The Bothnian formation seems to par-
allelize well with the Upper Keewatin of Minnesota, both pet-
rographically and structurally.
The latest granitic invasion in Finland, as described by
Sederholm' in the guide-book of the excursions of the
Seventh International Congress of Geologists, is that which
cuts the Bothnian formation. The earlier granite, and the
earlier schists associated with it, are found in fragments in the
Archean of Minnesota and Finland. — Winchell. 227
Bothnian formation all along the contact of the basal con-
glomerate on the pre-Bothnian gneiss; but the post-Both-
nian granite, which forms a large area next north of the Both-
nian schists, never occurs as pebbles in the schist, but as dikes
which are plainly of later date than the schist. It penetrates
the schist intimately, causing them to appear like a granc-
tized schist.
These phenomena are identical with those seen in Minne-
sota, where large areas of the elastics are affected by the me-
tamorphism incident to a granitic boss rising amongst the
schists and sending into them numerous apophyses and con-
verting them to schists and gneiss. This granite therefore
may be compared with our post-Keewatin granites seen at
Kekequabic lake and about Snowbank lake.
The only representative of our greenstone Lower Kee-
watin (our Kawishiwin) in Finland so far as now appears,
is the basic inclusions found in the pre-Bothnian granites.
The Minnesota and Finland Archean seem to be adjustible
for comparison in the following m.anner:
In Minnesota, • In Finland.
Granitic protrusion and meta- Post-Bothnian granite.
morphism. Bothnian schists.
»
Upper Keewatin.
Standing vertical, distinctly bed- Conglomerates, phyllytes, lep-
ded, clay slates, gray wackes, con- tytes, frequently rendered crystal-
glomerates, of great thickness, line by metamorphism, forming
sometimes changed to mica schists mica schists and porphyroids.
and to prophyroids.
Granitic and felsitic irruption Pre-Bothnian granite
and metamorphism. and gneiss.
Lower Keewatin,
Graywackes, varying to green-
wackes by increased amount of
chloritic and uralitic incrredients. The greenstones
Conglomerate, jaspilyte; also vast seem to be wanting, or are seen
amounts of greenstone which is only as inclusions in the pre-Both-
apparently of igneous origin and nian granite,
structure, this being at the bottom.
The fragmentalk are extensively
converted into mica schists and
gneiss.
In Canada, as is well known, the basal gneiss, or funda-
mental gneiss, was described by Logan many years ago, and
was named Laurentian. Along with this was also described
an Upper Laurentian which later has been rather discarded
228 The American Geologist, April, i8dK
since its principal component, the anorthosytes of the region,
has been found to be of igneous origin, and hence not a reliable
integral in a stratigraphic scheme. The Lower Laurentian,
or Laurentian proper, is divisible into two parts, viz: the fun-
damental gneiss proper, known also as the Ottawa gneiss, and
the Grenville series. In the Grenville series are limestones,
quartzytes and other interstratified beds which were undoubt-
edly derived originally from sedimentary deposition, and this
series, according to later observations, lies non-conformably
on the Ottawa gneiss. It is not known what chronologic
relation the Upper Laurentian, later known as the Norian,
bears to the Grenville series, except that it is of later date.
It may have been its immediate successor, or there may have
been a long interval of time, not there represented in the
stratigraphy, which elapsed between their dates of formation.
General considerations, however, of stratigraphy and of litli-
ology which the writer has presented elsewhere indicate that
there was no important interval of time between them, but
that probably the event which closed the Grenville age was
the anorthosyte invasion. General considerations also show
that it is probable that the Grenville series is represented in
the Adirondack mountains, where a similar series of gneisses
associated with anorthosyte is widely extended. This series,
characterized by marbles and quartzytes, extends into Ver-
mont and southward to New York and into New Jersey. In
Vermont and in New Jersey it is found that the limestones
are fossiliferous with Taconic trilobites, and that the series is
hence of Lower Cambrian age.
It' appears probable, therefore, that the Laurentian of
Canada, as recently re-defined by some of the Canadian geolo-
gists, is divisible between the Archean and the Lower Cam-
brian, and hence ftiat the divisions which have been given to
the Archean in that country cannot be the equivalent of
divisions which appear in Minnesota and in Finland. In
other words, it is probable that the divisions above detailed
for Minnesota and Finland are wholly embraced in the lower
division of the Canadian Laurentian, i. e., in the Ottawa
gneiss, and that they have not yet been noted in Canada. How
much of the Ottawa gneiss is to be attributed to the metamor-
phosed condition of fragmental strata which in other places in
The Term Augusta tn Geology.^Keyes, 229
Canada pass under the name Huronian, the equivalent of the
metamorphosed condition of the Keewatin of Minnesota, is
unknown, but it is quite likely that, as in Minnesota and in
Finland, rocks occupying the position of the so-called Huron-
ian of Canada also become, crystalline and in that condition
could not be distinguished from the typical Ottawa gneiss.
It is worthy of note also that the fundamental gneiss of
Canada is therefore not the bottom of the geological series,
but that it is largely a sedimentary formation, and that the
debris which went into its constitution was from some still
older series, and that this older series, or at least a portion of
it, was a greenstone, in part massive and in part stratified,
as indicated by the stratigraphic succession in Minnesota.
USE OF THE TERM AUGUSTA IN GEOLOGY.
By Charlbs R. Kbtes, Bes Moine», Iowa.
In a recent paper* on "The Batesville Sandstone of Arkan-
sas" there occurs the following statement:
"Some confusion has been introduced into the nomenclature of the
Mississippian formations in the adoption, by the Geological Surveys of
Iowa and Missouri of the term Augusta in place of Osage, for this
series [Osage Group] of strata. The name Osage was first proposed
by Williams in 1891 (Bull. U. S. Geol. Sur., No. 80, p. 409 [169]) to
include the Burlington and Keokuk groups of earlier authors. In 1892
Keyes (Bull. Geol. Soc. Am., vol. 3, p. 298) adopted the same name,
giving it the same significance, but in 1893 he proposed the name Au-
gusta (Iowa Geol. Sur., vol. i, p. 59) for the same series of strata. At
the time of the proposal of the name Augusta it was recognized by its
author as synonymous with Williams' term Osage; the only excuse
offered for the adoption of the new name was that at the localities on
the Osage River, from which the name Osage was derived, only a
portion of the whole series of strata are present, while at Augusta, la.,
a more complete section is exposed. This is, of course, an invalid
reason for the introduction of juch a synonym into geologic nomen-
clature. Other series of geologic strata have been named from localities
where only a portion of the whole series is exposed. The Chemung
group in a well established division in the New York series, yet at the
typical locality, Chemung Narrows, only a small portion of the whole
Formation is exposed. Other instances of the same kind could be
♦Trans. New York Acad. Sci., vol. XVI, p. 280, 1897.
230 The American Geologist, AprU, 1815
mentioned, but this is enough to show that such a precedent has been
established."
Attention is called at this time to the central point in the
note for several reasons: (i) There are inadvertently intro-
duced into this short paragraph seven mis-statements of fact,
five misrepresentations of published opinions on the subject,
and no less than four other deceptive factors, all of which, if
allowed to pass unnoticed, will have a tendency to perpetuate
**some confusion in the nomenclature of the Mississippian for-
mations''; (2) to avoid, if possible, further expression of erron-
eous statements which have been already several times repeat-
ed ; and (3) to present more clearly, than has been perhaps here-
tofore done, the exact meaning of the term in question as un-
derstood in its original definition.
In the first place the proposal of the term Augusta for one
of the main subdivisions of the Mississippian series was not with
the intention, as implied in the paragraph just quoted, of en-
larging the already burdensome synonymy that was known to
exist in the nomenclature of the geological formations of the
continental interior. In direct opposition it was an attempt
to find a name that would not only be appropriate, but that
would meet all the requirements of a recognized definition of
a geological formation. None existed at the time for the sub-
division defined, though the title Osage, as originally pro-
posed, had been evidently intended to occupy a somewhat
similar position — not identical as is shown farther on. The
latter name possibly might have been extended so as to cover
all the formations included by the other term had it been
found otherwise suitable. Inasmuch as Osage, after careful
investigation, did not prove to be adaptable it was thought
best to suggest a term that would obviate entirely all the ob-
jections that stood so conspicuously against the other.
Previous to the time of the formal proposal to unite the
Burlington and Keokuk limestones under a single title, the
strata of the Mississippi basin that were regarded as making .
up the lower Carboniferous series were commonly grouped
under six principal heads, viz: (i) Kinderhook. (2) Burling-
ton, (3) Keokuk, (4) Warsaw, (5) St. Louis, and (6) Chester
or Kaskaskia. These were the names which were used almost
invariably to designate the formations. Each wa-^ made up of
The Term Augusta in Geology. — Keyes. 231
several minor subdivisions which were widely recognized, and
some of th^m had even received special names.
For over a quarter of a century little attempt was made to
deviate from the old classification. As the more recent work-
ers in the region came to investigate critically the formations
and their fossils, it soon became manifest that an arrangement
different from the existing one more nearly expressed the
natural sequence of events, and that several of the commonly
recognized formations which were regarded as distinct, were
really parts of a single one. Among others the Lower
Burlington, the Upper Burlington and the Keokuk limestones
appeared to be very closely related. As early as 1862 White*
had called attention to the near relationships of thecrinoidsof
the three formations. Subsequently Wachsmuth and
Springer f revived the discussion. A decade later J particu-
lar stress was laid on the desirability of uniting the two Burl-
ington limestones and the Keokuk. No name was suggested
at this time for the reason that there were strong indications
that other and higher beds should be also included. Until
these higher deposits could be carefully examined it was
thought best not to propose any new titles, and accordingly
the naming was left open. Three years afterwards,§ before
the beds referred to could be inspected over their full areal
extent, the term Osage, which had been proposed in the mean-
while for the Burlington and Keokuk together, was used pro-
visionally in an extended sense.
The term Osage was first proposed by H. S. Williams 1 to
embrace the formations previously called the Burlington and
Keokuk limestones, the Warsaw being placed in a higher or
Ste. Genevieve. The original intention was to use, in this
connection, the term Ozark, and this name was actually
printed in a paper by professor Williams entitled "A Pre-
liminary Report on the Upper Palaeozoic Faunas of Missouri,"
that was to form pages 103 to 1 10 of Bulletin 3 of the Missouri
Geological Survey, issued in 1890. Owing to certain changes
♦Jour. Boston Soc. Nat. Hist., vol. VII, pp. 224-5, 1862.
tProc. Acad. Nat. Sci., Philadelphia, 1878, p. 224.
JAm. Jour. Sci., (3), vol. XXXVIII, pp. 191-192, 1889.
§ Classification Lower Carb. Rocks Miss. Valley, Pamphlet, pp. 24,
^Vashington, 1892.
IBulL U. S. GeoL Sun, No. 80, p. 169, 18915 and Ibid. p. 205.
232 The American Geologist. April. \m^
that were to be made, the paper was withdrawn after the page
proofs had been read, and it was never publishel, as the ma-
terial was largely incorporated in another and more extensive
memoir on the same subject which was to appear at the same
time. The printed, though unpublished Williams' notes are
of interest in this connection on account of containing a clearer
expression of the real meaning of the term Ozark (Osage)
than is found anywhere else. It is as follows :
"The Ozark group (d. of my table) is a group proposed to include
the formations' heretofore described as Encrinital limestone, Burlington
limestone, Keokuk group, and their equivalents in Missouri, Illinois and
Iowa, and part, if not all, of the Siliceous group of Tennessee, all of the
faunas of which indicate a close paleontologic relationship. It is pos-
sible that some of the formations heretofore referred to the Warsaw group
may more properly belong in this group.
The name Ozark group is sugg2Sted by the fact of the prominent de-
velopment of the formations constituting the group on the southern
and western margins of the Ozark uplift."
Before the publication of the name Ozark for the Burling-
ton and Keokuk it was learned that the name Ozark was to be
used by Prof. Broadhead in another connection and that
the paper announcing the fact was already in press. At the
suggestion of the latter the term Osage was substituted.
While the matter was pending in Missouri Prof. Will-
iams also made a communication to the Arkansas Geological
Survey on the same subject, using the name Osage. Subse-
quent and more exact correlations made in Arkansas show
tnat the formations included* in the "Osage group" were quite
different from those included in the sawie group in Missouri,
and embraced also a number of strata of uncertain age, some
of which are now known to form a part of the Kaskaskia. Al-
though later investigation showed clearly that a number of
formations that do not properly belong there were included
in the Osage, there is no definite intimation that Prof. Will-
iams at any time intended to take in any other members than
those beds commonly referred to the Burlington and Keo-
kuk. Indeed every reference made by this author to the
subject seems to indicate beyond all doubt that no other mean-
ing is to be attached to the term. In every allusion to the suc-
♦Arkansas Geol. Siir., Ann. Rep., 1888, vol. IV, p. xiii, iHoi; and ibid
Ann. Rep., i8qo, vol. 1, p. 113, 1891.
The Term Augusta in Geology. — Keyes. 233
cession containing the beds in question the typical Warsaw is
carefully excluded and placed in the St. Louis, as was done
by Worthen and most others. This is most distinctly shown
by the reference, quoted above, to the ** Keokuk group" being
included in the Osage, for the "Keokuk group" expressly ex-
cluded the typical Warsaw beds.
Another important point in the proposal of the term Osage
and the selection of the name from a locality in southwest
Missouri was that, owing to the unsatisfactory and indefinite
character of the then existing literature and notes pertaining
to that region, there was thought to be a *'mingling of faunas of
both Burlington and Keokuk beds." Later investigation,
however, has shown that Chouteau and the two limestones al-
ready mentioned are as sharply contrasted lithologically, faun-
ally and stratigraphically as along the Mississippi river where
these formations are typically developed.
In the prosecution of the geological survey of Missouri the
Carboniferous deposits were given special stratigraphical at-
tention. 1 he formations of the Mississippian series (Lower
Carboniferous) were taken up inparticular and traced from the
typical localities on the Mississippi river through the central
into the southwestern part of the state. In the original loca-
tions in southeastern Iowa, the Lower Burlington, the Upper
Burlington, the Keokuk, and the Warsaw (which had been
generally placed in the St. Louis) were found to contain essen-
tially the ^ame faunae, showing a continuous and progressive
evolution from the base to the top of the sequence. South-
westwardly, around the Ozark uplift the typical section was
found as far as the Missouri river, but beyond this point, for
a distance of over 100 miles, was more or less largely removed
through erosion (previous to the deposition of the Coal
Measures). The whole Lower Carboniferous belt rapidly
narrowed from a width of 75 miles on the north and on the
south to less than a dozen miles, and at some points was re-
duced to a mere thread, with only a limited vertical exposure
m the low bluffs of some stream. In the extreme' southwest
parts of Missouri and in Indian territory and Arkansas, the
Burlington and higher formations again assumed their full
development and features almost identical with those shown in
234 The American Geologist April, i89«
the typical localities. With these conditions existing it did
not seem advisable to attempt to retain the term Osage.
Theoretically the Osage river should cut through the whole
Lower Carboniferous; in reality it touched only the lower
portion, no higher than upper part of the Lower Burling-
ton. To one who had not visited the locality it was safe to
assume that the full sequence was present; accidental circum-
stances intervened. It was not feasible either to use the
term in a sense entirely new from that originally intended, or
to modify it to such an extent as to make it meet all the ob-
jections that it presented in its original form.
On the whole, after the most careful deliberation, it was
decided that much less confusion would ensue, and the ends
of geological nomenclature would be better subserved by drop-
ping the name Osage, and using some other term, especially
since the subdivision covered by the term Osage and that to
be called by the new title were not the same. The objections
urged against the extension of the word Osage for one of the
main subdivisions of the Mississippian series were as follows:
1. The lines of demarkation for certain of the principal
subdivisions of the Mississippian series are not to be drawn at
the horizons indicated by the name Osage, if the faunal char-
acters of the sequence are to be taken into consideration, and
if the most natural divisional planes are to be sought. Were
it not for this one fact the other objections raised might be
passed over, and the application of the term extended. The
most serious stumbling block in the way of the proper con-
sideration of the Mississippian formations has been the War-
saw, and the general misconception regarding the various
beds called by this name but belonging to many different hori-
zons, has done more than any other factor in preventing a
clear understanding of the Lower Carboniferous stratigraphy
of this region.
2. The unfortunate selection of the section to be consid-
ered the typical one. As a matter of fact it is the most non-
typical one known.
3. Only a single one of the six distinctive formations
belonging to the subdivision is present in the vicinity of the
typical section of the Osage. As already staled, the Lower
I^urlington Hmestone, and this not fully, appears to be the only
Drumlim in Glasgow, — Upkam, 235
part represented on the Osage river, and the width of the belt
occupied by the formation is practically reduced to nil. It
is a mere vertical exposure of very limited extent in low river
bluffs^ with the Chouteau limestones at the base and the Coal
Measures at the top.
4. The chief reason for selecting the term Osage — that
there is a mingling or mixing of Keokuk and Burlington
forms in southwest Missouri — does not appear valid, since the
successive faunas are, in reality, as sharply defined and as
clearly separated from one another as they are farther north, in
southeastern Iowa.
The desirability of a definite term to properly express the
stratigraphical and faunal relationships of a part of the Missis-
sippian series being recognized, and no name already in use
being available, even by the most liberal modification of mean-
ing, a title was selected from the neighborhood of the typical
developments of the several formations that it was proposed
to unite. Hence the suggestion ol Augusta.
Instead of **at the time of the proposal of the name Augusta
was it recognized by its author as synonymous with Williams'
term Osage" it was considered as distinctly not synonymous.
Furthermore a recent note received from the author of Osage
states that the term Augusta will probably have to stand. It
may be inferred, therefore, that any "confusion introduced into
the nomenclature of the Mississippian formations by the term
Augusta in place of Osage'* has not been "by the Geological
Surveys of Iowa and Missouri."
[European ami American Glacial Geology Compared, III.]
DRUMLINS IN GLASGOW.
By Wahren Upham, St. Paul, Minn.
The sight of a few drumlins near Appleby, Grasmere, and
Keswick, as noted in the second paper of this series, made me
eager to see more of these peculiar drift hills, of which, so
far as they are developed in England and Scotland, little has
been written. In our journey from Keswick, over the Sol way
lowlands and past the Cheviot hills to Edinburgh, and on-
ward in the moderately hilly agricultural region of eastern
236 The American Geologist AprU, ia«
and northern Scotland to Inverness, although drumlins were
constantly looked for, none were seen and the outlook on each
side from the railways is generally extensive, ranging miles
away, over cultivated or pastured tracts, without woods to
conceal the glacial drift and the minor topographic features.
Returning southward along loch Ness and the Calendon-
ian canal, with its other lochs, in the Great Glen of Scotland,
which divides the mighty .'mountains of the Highlands by a
pass only about 100 feet above the sea, to Fort William, and
thence continuing southward by the recently built West
Highland railway, by lochs in deep mountain gorges, over
broad, high moors bearing many marginal moraines, and
through the grand and beautiful scenery of loch Lomond, loch
Long,Gare loch,and the Clyde estuary, still I saw no drumlins.
But as our train came into the northern suburbs of Glasgow,
passing Mary Hill, Possil Park, and Cowlairs stations, many
drumlins were observed, closely adjoining our railway on
each side and promising, by their admirably typical develop-
ment, that they were part of a very interesting drumlin dis-
trict.
During the next three days, July 3rd to the 5th, of last
summer, I walked nearly fifty miles in the city of Glasgow
and its near environs to map its seventy-five and more drum-
lins, which have the same irregular distribution and frequently
compound grouping as in southern New Hampshire and
northeastern Massachusetts, where I had mapped many of
these remarkable drift hills, the first so delineated and par-
ticularly described in America, twenty years ago.* In more
recent years the thorough exploration by Prof. George II.
Barton has recorded the detailed distribution and special char-
acters of the fifteen hundred drumlins of Massachusetts, a
state which has many tracts of these hills similar to Glasgow,
but scarcely any superior. The Glasgow drumlins are closely
like those of New England in their outlines, being smoothly
oval, and trending east-southeasterly in parallelism with the drift
transportation and striae; in their material, which is the usual
tiller boulder-clay, rarely containing a nucleus of rock; in their
areas, from a quarter to two-thirds of a mile long, with mostly
♦Geology of X. H., \'ol. Ill, 1878, pp. 285-30^, with a heliotype
plate, a section, and five atlas sheets.
Drumlifts in Glasgow. — Upkam, 237
a half to two-thirds as great width ; and in their altitude, which
is mostly from 50 or 75 to 125 feet above the contiguous lower
ground, while their extremes range from 30 or 40 feet up to
about 150 feet.
None of the drumlins of Glasgow are extremely elongated
and sharp-crested, like some in the Central New York district,
and like the ispatinows described and so named by Tyrrell in
the north central part of the Dominion of Canada, west of
Hudson bay; nor are any of quite circular area, like the mam-
millary drumlins of some localities in Wisconsin, as described
by Chamberlin. From whatever point of view they are seen,
the Glasgow hills rise in the graceful rounded forms which
suggested to Hitchcock the early name, "lenticular hills," ap-
plied to them in the third volume of the New Hampshire Geo-
logical Survey.
These hills, hitherto unnoted by geologists or mentioned in
the briefest terms in papers treating of other portions of the
geology of the region, are, I think, the first drumlins definitely
mapped in Great Britain; but in the lar-Connaught region ot
Ireland, somewhat more elongated drumlins, occurring in
great numbers, were mapped so early as in 1872 by Kinahan
and Close. It is to be hoped that the Scottish and English
drumlins will soon have equally elaborate mapping, that their
:^eneral distribution and grouping may be well known, lead-
ing probably, with the sunilar studies made in America, to a
j-;ccd cgrecment among geologists in their explanations of
the mode of accumulation of these prominent smooth hills of
glacial drift.
Perhaps the most significant fact concerning drumlins is
iheir gregariousness. Both in America and in the British
Isles, they are amassed on some tracts in great profusion,
while other and much more extensive drift-bearing regions
have none. On the great glaciated areas of continental Eu-
rope, only very few and limited districts bear drumlins. Their
most notable district was described by Keilhack, with map-
ping of the many drumlins, two years ago, on the east side of
the lower part of the river Oder, in northern Germany.*
♦Jahrbnch, k. preuss. ^^i)\. Landesanstalt, i8q6, pp. i6j-i88, with
inajis. About 2,200 drumlins are ina|)ped by Keilhack in this district ;
but many of small size are omitted from his map. The whole number of
drumlins in this district, which is 60 miles long from north to south and
from 20 to 40 miles wide, is estimated at 3.0(K). They are mostly from 15
to 50 feet high, but some attain liights of 80 to lop feet.
238 The American Geologist, April. j«»t*
Some of these drumlins are much elongated, to an extent of
two or three miles ; and their longer axes trend toward an ad-
jacent looped marginal moraine, betokening their deposition
and moulding by the ice-sheet at the same stage, during its
general retreat, when the moraine was formed. In Sweden,
so far as Baron De Geer has observed during very extensive
explorations, drumlins are almost entirely absent. In my
journeys through Holland, Germany, Denmark, Norway to
Trondhjem, and thence east into Sweden and south in that
country to Stockholm and Goteborg, no drumlins were found :
and I fully agree with De Geer that probably they are no-
where well developed on the Scandinavian peninsula.
Why and how did the ice-sheets form so abundant drum-
lins in some limited parts of New England, as notably about
Boston and. Worcester, also in New York and southeastern
Wisconsin, in the lar-Connaught district, and in the Clyde
valley at Glasgow, while other areas apparently not less fa-
vorably situated are destitute of such hills? and in what way
could the broad, deep sheets of slowly moving land-ice heap
up these prominent masses of the unmodified glacial drift?
It is entirely easy to account for the retreatal moraine hills
of our continental ice-sheets, of which we have the counter-
parts at the ends of now existing glaciers. Scarcely more diffi-
culty is encountered in ascertaining the mode of formation of
kames and eskers, which are knolls and ridges of modified
drift gravel and sand deposited by streams walled in part by
ice and therefore left by its melting in high pinnacles and
ridges. Drumlins, on the other hand, differ from any ob-
served product of the present puny glaciers of the Alps and
other mountain districts; but Chamberlin's observations and
photographs of the borders of the Greenland ice-sheet give
some suggestions of their origin.*
The view which appears to me to afford the fullest explana-
tion of the origin of drumlins, in a brief statement, refers their
accumulation to convergent currents of the irregularly in-
dented and channelled border of the ice-sheet during its re-
treat, when a layer of drift, having become sui)erglacial, as
on the Malaspina glacier, was enveloped by a later onflow of
♦Bulletin, Cicol. Soc. Anu-r., Vol. VI, pp. 199-220, with ti^ht plates,
PVb. 1895.
Drumlins in Glasgow. — Upham. 239
ice above it, being then amassed englacially or subglacially
in these hills very near to' the boundary of the ice, that is,
within a few miles or probably in some cases within even less
than one mile.* They are thus attributed to unusual condi-
tions of climate interrupting or slackening the recession of
the glacial boundary at the close of the Ice age, being excep-
tional accumulations of the ground moraine, somewhat an-
alogous to the knolly and irregular masses of marginal
moraines, but of much rarer development and probably no-
where traceable in such prolonged belts.
l-'or concise presentation of my notes of the Glasgow drum-
lins. they arc herewith arranged in a table: and outlines of
these hills, with their altitudes in feet above the sea, are given
on the accompanying map, which also shows the railways of
the city and their stations, while the streets, on so small a scale,
are necessarily omitted. The area mapped is about five miles
square, the greater part of which is occupied by the city, the
commercial and manufacturing metropolis of Scotland, which
has grown during the past hundred years from about 80,000
to about 900.000 people.
Beyond the limits of the map, numerous other drumlins
were seen within a few miles, and some of them were ascended
and examined. The most conspicuous of these is Gilshoc
hill, on the northwest, rising about 275 feet above the sea and
175 feet above its western base, close outside the map border.
near Mary Hill railway station and near the crossing of the
river Kelvin by the Forth and Clyde canal.
In the following table, the order of the drumlins shown
on the map is from north to south, and secondarily from west
to east, with numbering for possible reference in any later
work. \umbers i to 16 are west of the river Kelvin; num-
bers 17 to 44 are north of the Forth and Clyde canal and of
the Monkland canal continuing eastward; numbers 45 to 59
are east of the river Kelvin and south nf the canal; and num-
bers 60 to 87 are south of the river Clyde. In two columns
:iV, pp. -iz^iM. April.
zussLonbv Profs. W. M.
^oliiKisl. Vol. X, tip. 23g-
ol. XIV, ]ip. 60-83. Aug.
240
The American Geologist.
April, 1S98
KMhtrg^ltii
DRUMLINS IN Gi.ASGOW.
the altitudes of the hill tops are given, first, above the Clyde
and the sea, and, second, above the base of the hills. Exact
altitudes from the published Ordnance Survey sheet are tran-
scribed for many of the hill summits; but others, with all the
hights above the bases, are estimated. The ratios of elonga-
tion of these drumlins are stated in the quotient of the length
divided by the width. Streets crossing the drumlins in the
city* are noted, precedence being given to streets running par-
allel, or nearly so, with the trends of the hills, that is, from
west to east or southeasterly, while the second street named
crosses the other upon the hill.
DrunUins in Glasgow. — Uphant,
241
Notes of the Drumlins op Glasgow,
Name. Hifpht
in feet
above
sea.
We9t of the River Kelvin:
1. Flemin^toD hill 150
2. Asylum hill 123
3. Woodcroft hill 125
4. NextS. W 80
5. Broom or Oswald hill 126
e. Jordan hill 60
7. West Balfirray hill 177
8. Mont8:omerie hill 175
9. Close S 150
10. Garden hUl 146
11. Academy hill 150
12. Observatory hill 18.)
13. Dowan hill 140
14. Partickhill 144
15. HillHead 160
16. University hill 125
formerly Gilmore (Gil-
mour) hill.
17.
Hi^ht Length
above
base, width.
75
2
60
2
60
2
50
2
100
2
40
2
100
2
100
2
75
1.5
75
2
75
1.4
100
2.5
100.
2
120
2
J 20
1.5 •
100
1.7
Screets, and other remarks.
North of the canal :
Tam's hill, most N. W.
220
7i 1.5
18. Closes 260 125
19. NextE 210 60
20. Fossil Park hill 2.'H) 100
21. FirhillN.E 217 50
22. do., Central 271 100
23. do.,S.W 225 75
24. NextS.E 236 80
25. Hamiltonhlll 245 100
28. Keppochill, N 2\0 75
27. do.. Central 265 90
28. do.,S 2.W 75
29. Hundr<^d Acre hill 2.W 100
30. E. of Possil Park 235 5'J
31. station, four 232 50
:^. summits. N., S. 247 65
3i. E., andS. £. 220 40
34. NextE 240 6:)
35. E. of Cowlairs station 270 90
Much till is smoothly amu:ised on the
Sprlngrburn Park (360 feet above sea).
36. N. £. of SpringburnPark. 300 75
37. Peter'.shill 225
:«. Sighthill 260
:». NextS 220
40. Broom hill 224
41. Garngadhill 256
42. Barn hill 225
43. High Broomfleld hill 290
44. Blochairn hill 285
.7
.8
J
1,
2
2
"2
1.4
1.7
1.7
2
2
2
1.6
2.5
2
1.5
1.5
1.6
1.6
Beside the Great Western Road.
Koyal Lunatic Asylum.
Woodcroft House.
N. E. of Victoria Park.
Crow Road : Broom Hill Drive.
Beside Dumbarton Road.
West Balgray House.
MontKomerie Crescent.
Great Western Road.
Royal Botanic Garden.
£. of Kelvinside Academy.
Glasgow Observatory.
Crown Terrace.
Partick Hill St.
Great George St. ; HlUhead St.
Cut down n bout 50 feet from its
original hight.
Numerous large drumlin^i witliiu
two miles W. and N.
N. of Ruchill station.
Cut by railway.
Park House.
Ruchill Hospital.
RuchUl Park.
. do.
Allander St.
W. of Hamilton Hill House.
Allander St. ; Ashfleld St.
W. of Cowlairs Works.
Wardlaw St.
S. of St. John St.
Between the Saracen
Foundry and Ashfleld ;
No. 33 cut by railway.
Carlyle Si.
Hill St. ; cut by railway.
western slopes of the rock highland of
Frequent drumlins seen east-
ward ; few northward.
N. of Peter's Hill Road.
Sigh thill Cemetery.
W. of St. Roiloz station.
Two railway tunnelis.
Gamgad Hill St.
Poorhouse.
Garngad and Milton Roa<l.
iilocluiirn Road and Hou.^e.
40
1.5
75
1.8
40
65
90
50
1.6
125
12.-)
2
242
The American Geologist,
AprU, 188K
45.
46.
47.
48.
49.
50.
51.
52.
.W.
.H.
55.
56.
57.
58.
59.
60.
61.
62.
68.
64.
65.
66.
67.
68.
69.
70.
71.
72.
7H.
74.
75.
76.
77.
78.
79.
80.
81.
S2.
K\.
S4.
S5.
S<>.
S7.
East of the River Kehnn and aouih of the canal :
Kelboume hill 150 80 1.5 S. of Kelbourne St.
Sheep mount 198 125 1.6 Oxford and Cambridge Drives.
York hill 135 110 2 E. of York Hill station.
Parkhill 150 125 1.8 West End Park and Circle.
Cranston hill 85 50 1.6 Cranston St. : Lancefleld St.
Garnethill 175 100. 1.8 Hill St. ; Scott St.
Closes 137 100 1.5 Jane St. ; Douglas St.
Next E 160 100 2 Holmhead St. ; Frederick St.
CloseS.E 139 100 2 Richmond St. ; Montrose St.
Necropolis hill 195 100 1.4 Cemetery ; rock veneered with till.
North hill in Alexandra
Park 230 80 1.7 Nos. 55 and 56 in Alexandra Park.
Kennyhill 231 80 2
Haghill 174 75 2 Haghill House.
Next S 110 25 2 W. of Nursery,
Eastern Necropolis hill.... 110 50 1.6 Cemetery.
South of the River Clyde :
Craigton hill 150 90 1.6 Craigton House.
Ibrrjx hill 165 100 1.5 Bollahouston House.
NextS. W 125 60 1.6 S. of Wearieston House.
Mosspark hill 175 110 1.5 S. of Mosspark House.
S. of Bellahonston station . 120 70 2 N. of Nithsdale Road.
CJose S 147 90 2 S. of this road.
Hagrgswood hill 170 100 2 Haggbowse.
Closes. W 125 50 1.5 E. of Mossfarm Cottage.
CloseS.E 140 70 2 Haggswood Nursery.
North Wood hill 140 70 1.5 S. part of woods. '
Pollok hill 125 50 I.] E. of PoUok House.
Pollokshaws hill 150 75 2 W. of railway station.
S. W. of Pollokshields sta-
tion 125 75 2 Bruce Road.
NextS.W 120 70 2.5 Between Aytoun and Nithsdale
RoadH.
NextS 137 85 2 Newark Drive ; Leslie Road.
CloseS.E 110 60 2 Titwood Nursery.
Shawlands hill 140 75 1.8 Cut by raUway.
Closes 125 60 1.8 Maxwell St.
Constonhill 150 75 1.8 Cut by railway.
Langside hill 185 100 2 Langside House.
Camphill 211 140 1.5 Queen's Park.
Crossbill 160 90 1.6 Queen Mary's Ave. ; cut by rail-
way.
Mount Florida 175 100 2 Prosi>ect Hill Road.
Clincart hill 160 80 1.8 Cut by railway.
Coplaw hill 95 40 1.8 Nursery.
Govanhill 97 50 1.7 Go van Hill St.
Polmadie hill 140 100 1.8 S. of Polmadip House.
NextS 200 125 2 New Houhc.
In passing by railway northeast and east, through Bishop-
bridge and Falkirk, to Edinburgh, drumlins were seen in fair
development for about ten miles from Glasgow. Somewhat
fluted contour of the till is observable thence to Edinburgh
Drumlins in Glasgow. — Upham. 243
and to Dunbar, with rarely a typical drumlin; a few drumlins
being noted near Linlithgow, and again a few miles west of
Dunbar. But none were seen farther southeast and south,
on the route to Berwick, York, Cambridge, and Harwich.
The Carboniferous bed-rocks of Glasgow lie generally at
only a slight depth beneath the bases of the drumlins, form-
ing the general ascent of the country on each side of the Clyde.
A confluent ice-sheet, flowing down mainly from the
Grampian Highlands on the north and northwest, but partly
from the Southern Uplands, moved eastward over the central
Clyde and Forth lowlands and pushed against the Scandina-
vian ice-sheet, with which it was confluent on the present area
of the North Sea. During the recession and departure of
these icefields, a time came when the eastern front of the
Scottish ice withdrew from the region of Edinburgh westerly
past Glasgow; and at that time I think the drumlins of the
Clyde district, so abundantly developed in Glasgow, to have
been amassed.
Later, when the ice-sheet had retreated so far as to admit
the sea to this valley, its fossiliferous beds and shore lines,
about 50 and 25 feet above the present sea level, analogues of
those of the Champlain epoch in America, extended along the
Clyde valley. Men at that early date lived and fished here,
and lost their dug-out canoes, of which about twenty, varying
from 9 to 27 feet in length, have been found in these marine
beds in and near Glasgow. These beds overlie the bases of
the lower drumlins near the Clyde. Finally, at the end of the
Ice age, the last remnants of the Scottish ice-sheet, which
lingered as mountain glaciers, melted away; and the land, re-
lieved from its glacial burden, rose to its present hight. Sub-
sequent time has been short, in a geological sense, for the
slopes of the drumlins show scarcely any subaerial erosion;
their forms remain as they were moulded by the great over-
riding sheet of land ice.
244 The American Geologist AprU. i898
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
Le GyPse de Paris et les miniraux qui V accompagnenL A. Lacroix.
(Nouvelles Archives des Museum d' Histoire Naturelle, Paris, tome
X, 1897.)
It is probably true, as remarked by the author, that there are few
sedimentary regions as rich in minerals as the basin of Paris. It is
equally true that there are few that have been so thoroughly searched
and so long studied. Modern mineralogy may be said to have had itb
beginning in the Paris basin, and from the same center have gone out
successively the great works of Rome de Lisle, Haiiy, Brongniart,
Becquerel and Decloiseaux. The present work is no mean successor
of the earlier parts of this series. The author denominates this his
"premier memoire" on this subject, and promises to follow up the
subject, but it is difHcult to conceive what further there is to be. said.
The gypsum of the Paris basin is found to lie in strata extending
from the lower Oligocene to the Senonian of the upper Cretaceous, the
last, however, being considered to have received it by secondary deposi-
tion. The crystals of gypsum, which are often magnificent, reaching the
dimension of six to eight inches, are often twinned and repeated in a
multiplicity of ways. These forms are mineralogically described and
often illustrated by photography on a series of elegant plates.
The accompanying minerals, often formed by the transformation of
gypsum, largely by the action of pyrite and atmospheric air and water,
are the following: pyrite, common salt, celestite, menilite, calcite,
opal, magnesite, quartz, lutecite, chalcedony, fluorite, apetalite, mar-
casite, blende, websterite, melanterite, phosphorite, vivianite, siderite,
succinite.
Gypsum occurs not only in crystals, but as strata that have a
thickness sometimes reaching 90 feet. From these strata it has been
quarried for many years, furnishing the celebrated "plaster of Paris."
One of the most interesting of the above minerals is lutecite, a form
of quartz, lately discovered and described by Michel-Levy and Munier-
Chalmas (Bui. Soc. Min. France, XV, 159, 1892). It is sometimes
fibrous and sometimes in macroscopic crystals: when fibrous it differs
from both chalcedony and quartzine in the relation the fibers bear, in
their greatest dimension, to the axes of elasticity. In chalcedony they
are elongated parallel to the index of elasticity np and in quartzine
parallel to n^. In lutecite they are elongated in a direction of the
plane ng, nm, making with ng an angle which is not yet established
definitely but which is about Z2 degrees (Wallerant). When lutecite
appears in crystals they are short, hexagonal, doubly terminated pyra-
mids, always united in series by their pyramidal faces or twinned by
their bases. "♦ **• ^.
Authors^ Catalogue. 245
MONTHLY AUTHORS' CATALOGUE
OF American Geological Literature,
Arranged Alphabetically.*
Adams, F. D.
Nodular granite from Pine lake, Ontario, (Geol. Soc. Amer., Bull,
vol. 9, pp. 163-172, pi. II, Feb. 10, 1898.)
Adams, C I.
A geological map of Logan and Gove counties [Kansas]. (Kansas
Univ. Quarterly, vol 7, sen A, pp. 19-20, Jan. 1898.)
Ami, H. M.
Notes on the geology of Chelsea, Que,, and some of its bearings on
the geology of Ottawa. (4 pp.; reprinted with emendations from Ot-
tawa Naturalist, vol. 9, pp. 125-127, Sept. 1897.)
Ami, H. M.
Synopsis of the geology of Montreal. (5 pp., author's edition, Dec.
1897. Ex. British Medical Ass. guide and souvenir, pp. 45-49, Montreal,
1897.)
Becker, G. F.
The Witwatersrand banket, with notes on other gold-bearing pud-
ding stones. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 1-36, pi. i,
T897.)
Becker, G. F.
Reconnaissance of the gold fields of southern Alaska, with some notes
on general geology. (U. S. Geol. Survey, i8th Ann. Rept., pt. 3, pp.
1-86, pis. 1-31, 1898.)
Becker, G. F.
The auriferous conglomerate of the Transvaal. (Am. Jour. Sci., ser.
4. vol. 5, pp. 193-208, Mch. 1898.)
Beede, J. W.
New corals from the Kansas Carboniferous. (Kansas Univ. Quar-
terly, vol. 7, ser. A, pp. 17-18, Jan. 1898.)
Beede, J. W.
The stratigraphy of Shawnee county [Kansas]. (Kans. Acad. Sci.,
Trans., vol. 15, pp. 27-34, 1898.)
Beede, J. W.
The McPherson Equus beds. (Kans. Acad. Sci., Trans., vol. 15,
pp. 104- no, pis. 2-4, 1898.)
Beede, J. W.
Notes on Kansas physiography. (Kans. Acad. Sci., Trans., vol. 15,
pp. i!4-i20, pis. 7-9, 1898.)
*Thi8 list includes titles of articles received up to the 20th of the preceding
mnn^, includin^r general geology, physiography, paleontology, petrology and
mineralogy.
248 The Amefkan Geologist. April, iiwp
Keyes, C. R.
Structure of the coal deposits oi the Trans- Mississippian field. (Eng.
and Mining Jour., vol. 65, pp. 253-254. Feb. 26, 1898; pp. 280-281, Mch.
Kimball, J. P.
Residual concentration by weathering as a mode o( genesis of iron
ores. (Am. Geol,, vol. 2i, pp. 155-163, Mch. 1898.)
Knerr, E. B.
Baritc nodules in wood. (Kans. Acad. Sci., Trans., vol. 15, pp.
mineral waters. (Kan^.
vol. 15, pp. (KS-09, lOQO-^
Knight, W. C.
Some new Jurassic vertebrates from Wyoming. First paper. (Am.
Jour. Sci., ser. 4, vol. 5, p. 186, Mch. 1898.)
Leverett, Frank.
Correlation of moraines with beaches on the border oi lake Eric,
(Am. Geol., vol. 21, pp. 195-199. Mch. 1898.)
Luquer, L. Mel.
Optical scheme. (School of Mines Quarterly, vol. 19, pp. 93-96.
Nov. 1897-)
Matthew, W. D.
A revision of the Puerco fauna. (Am. Mus. Nat. Hist., Bull., vol. 9.
pp. 259-323, 1897.)
Mead, J. R.
The drill hole at Wichita [Kansas]. (Kans. Acad. Sci., Trans., vol.
15. pp. 20-22, 1898.)
Moses, A. J.
The gcoznelrical characters of crystals. Part I of introduction to
the study and experimental delerminaticn of the characters of crystals.
(Contributions from the Dept. of Mineralogy, Colnmbia Univ., vol. 6,
no. 10. pp. 1-84. Reprinted from School of Mines Quarterly, vol. 18.
pp. 266-286, Apr. 1897; vol. 18, pp. 385-422, July 1897; vol. 19, pp, 14-35.
Nov. 1897.)
Newberry, J. S.
New species and a 1
2-24. 1897.)
Osborn, H. F.
The Hueriano lake tuisin, s
and Bridger fauna. (.\m. Mu;
■ «97.)
Powell, J. W.
An hypothesis to aciniinl for
{Jour. Geol., vol, 6, pp. i-g, Jar
Authors' Catalogue. 249
Quereau, E. C.
Topography and history of Jameavillelake, New York. (Geol. Soc.
Amer., Bull., vol. 9, pp. 173-182, pis. 12-14, Feb. 17, 1898.)
Schuchert, Charles.
Dipeltis an insect larva. (Natural Science, vol. 12, p. 215, Mch. 1898)
Slichter, C. S.
Note on pressure wiihin the earth. Qour. Geo!., vol. 6, pp. 65-78,
Jaa-Feb. 1898.)
Smyth, B. B.
The closing of Michigan glacial lakes. (Kans. Acad. Sci., Trans.,
vol. IS, pp. 23-27. 1898.)
Smyth, B. B.
The buried moraine of the Shunganunga [Kansas]. (Kans. Acad
Sci., Trans., vol. 15, pp. 95-104, pi. I, 1898.)
Stewart, Alban.
A contribution lo the knowledge of the ichthyic fauna of the Kansas
Cretaceous. (Kansas Univ. Quarterly, vol. 7, ser. A, pp. 21-29, p's.
1-2, Jan. 1898.)
Tarr, R. S.
The physical geography of New York state. (Am. Geog. Soc, Bull,,
vol. 30, no. 1, pp. i8-56. 1898.)
Udden, J. A-
A new well at Rock Island, Ills. (Am. Geol., vol. 21, pp. 199-200,
Mch. 1898.)
Upham^ Warren.
Valley moraines and drumlins in the English Lake district. (Am.
Geol., vol. 21, pp. 165-170, Mch. 1898.)
Van HIse, C. R.
Estimates and causes of crustal shortening. Gour. Geo!., vol. 6.
pp. io-64. Jan.-Feb. 1898.)
Wadsworth, M. E-
Some methods of determining the positive and negative character
of mineral plates in converging polarized light with the petrographical
microscope. (Am. Geo!., vol. 21, pp. 170-175. Mch. 1898.)
Walker, T. L.
Examination of some triclinic minerals by means of etching figures.
(Am. Jour. Sci., ser. 4, vol. 5, PP- 176-185, Mch. 1898.)
Weller, Stuart.
248 The Ametican Geologist. April. \m>
Keyes, C. R.
Structure of the coal deposits of the Trans- Mississippian field. (Eng.
and Mining Jour., vol. 65, pp. 253-254, Feb. 26, 1898; pp. 280-281, Mch.
5, 1898.)
Kimball, J. P.
Residual concentration by weathering as a mode of genesis of iron
ores. (Am. Geol., vol. 21, pp. 155-163, Mch. 1898.)
Knerr, E, B.
Barite nodules in wood. (Kans. Acad. Sci., Trans., vol. 15, pp.
80-81, 1898.)
Knerr, E. B.
Atchison and Nemaha county [Kansas] mineral waters. (Kans.
Acad. Sci., Trans., vol. 15, pp. 88-89, 1898.)
Knight, W. C.
Some new Jurassic vertebrates from Wyoming. First paper. (Am.
Jour. Sci., ser. 4, vol. 5, p. 186, Mch. 1898.)
Leverett, Frank.
Correlation of moraines with beaches on the border of lake Erie.
(Am. Geol., vol. 21, pp. 195-199, Mch. 1898.)
Luquer, L. McI.
Optical scheme. (School of Mines Quarterly, vol. 19, pp. 93-96.
Nov. 1897.)
Mattl^ew, W. D.
A revision of the Puerco fauna. (Am. Mus. Nat. Hist., Bull., vol. 9.
pp. 259-323, 1897.)
Mead, J. R.
The drill hole at Wichita [Kansas]. (Kans. Acad. Sci., Trans., vol.
15, pp. 20-22, 1898.)
M0S68, A. J.
The geometrical characters of crystals. Part I of introduction to
the study and experimental determination of the characters of crystals.
(Contributions from the Dept. of Mineralogy, Columbia Univ., vol. 6,
no. 10, pp. 1-84. Reprinted from School of Mines Quarterly, vol. 18.
pp. 266-286, Apr. 1897; vol. 18, pp. 385-422, July 1897; vol. 19, pp. 14-35-
Nov. 1897.)
Newberry, J. S.
New species and a new genus of American Palaeozoic fishes, together
with notes on the genera Oracanthus, Dactylodus, Polyrhizodus, Sandal-
odus, Deltodus. [From a nearly completed MS. (1890-1891), edited by
Bashford Dean.] (N. Y. Acad. Sci., Trans., vol. 16, pp. 282-304, pis.
22-24, 1897.)
Osborn, H. F.
The Huerfano lake basin, southern Colorado, and its Wind River
and Bridger fauna. (Am. Mus. Nat. Hist., Bull., vol. 9, pp. 247-258,
1897.)
Powell, J. W.
An hypothesis to account tor the movement in the crust of the earth.
(Jour. Geol., vol. 6, pp. 1-9, Jan. -Feb. 1898.)
Authors' Catalogue, 249
Quereau, E. C.
Topography and history of Jamesville lake, New York. (Geol. Soc.
Amer., Bull., vol. 9, pp. 173-182, pis. 12-14, Feb. 17, 1898.)
Schuchert, Charles.
Dipeltis an insect larva. (Natural Science, vol. 12, p. 215, Mch. 1898.)
Slichter, C. S.
Note on pressure within the earth. (Jour. Geol., vol. 6, pp. 65-78,
Jan.-Feb. 1898.)
Smyth, B. B.
The closing of Michigan glacial lakes. (Kans. Acad. Sci., Trans.,
vol. 15, pp. 23-27, 1898.)
Smyth, B. B.
The buried moraine of the Shunganunga [Kansas]. (Kans. Acad.
Sci., Trans., vol. 15, pp. 95-104, pl- i, 1898.)
Stewart, Alban.
A contribution to the knowledge of the ichthyic fauna of the Kansas
Cretaceous. (Kansas Univ. Quarterly, vol. 7, ser. A, pp. 21-29, pis.
1-2, Jan. 1898.)
Tarr, R. S.
The physical geography of New York state. (Am. Geog. Soc, Bull.,
vol. 30, no. I, pp. i8-50, 1898.)
Udden, J. A-
A new well at Rock Island, Ills. (Am. Geol., vol. 21, pp. 199-200,
Mch. 1898.)
Upham, Warren.
Valley moraines and drumlins in the English Lake district. (Am.
Geol, vol. 21, pp. 165-170, Mch. 1898.)
Van Hise, C R.
Estimates and causes of crustal shortening. (Jour. Geol., vol. 6,
pp. 10-64, Jan.-Feb. 1898.)
Wadsworth, M. E.
Some methods of deterniining the positive and negative character
of mineral plates in converging polarized light with the petrographical
microscope. (Am. Geol., vol. 21, pp. 170-175, Mch. 1898.)
Walker, T. L.
Examination of some triclinic minerals by means of etching fignires.
(Am. Jour. Sci., ser. 4, vol. 5, pp. 176-185, Mch. 1898.)
Weller, Stuart.
Description of a new species of Hydrcionocrinus from the Coal
Measures of ICansas. (N. Y. Acad. Sci., Trans., vol. 16, pp. 372-374,
pi. 2fi, Feb. 1898.)
Whitfield, R. P.
Descriptions of new species of Silurian fossils from near fort Cassin
and elsewhere on lake Champlain. (Am. Mus. Nat. Hist., Bull., vol. 9,
pp. 177-184, pis. 4-5, 1897.)
250 The American Geologist, AprU, i89h
Whitfield, R. P.
Note on the hypostome of Lichas (Terataspis) grandis Hall. (Am.
Mus. Nat. Hist., Bull., vol. 9, pp. 45-46, 1897.)
Whitfield, R. P.
Descriptions of new species of Rudistae from the Cretaceous rocks
of Jamaica, W. I., collected and presented by Mr. F. C. Nicholas. (Am.
Mus. Nat. Hist, Bull., vol. 9, pp. 185-196, pis. 6-22, 1897.)
Willis, Bailey.
Drift phenomena of Puget sound. (Geol. Soc. Amer., Bull., vol. g,
pp. 111-162, pis, 6-10, Feb. 8, 1898.)
Williston, S. W.
The Pleistocene of Kansas. (Kans. Acad. Sci., Trans., vol. 15.
pp. 90-94, 1898.)
Williston, S. W.
Notice of some vertebrate remains from the Kansas Permian. (Kans.
Acad. Sci., Trans., vol. 15, pp. 120-122, 1898.)
Wilson, J. W.
Geology of Effingham ridge [Kansas]. Preliminary report. (Kans.
Acad. Sci., Trans., vol. 15, pp. 113- 114, 1898.)
Wortman, J. L.
The Ganodonta and their relationship to the Edentata. (Am. Mus.
Nat. Hist., Bull., vol. 9, pp. 59-110. 1897.)
CORRESPONDENCE,
Archean Character of the Nuclei of the Antilles. In a pa-
per read by me before the British Association for the Advancement of Sci-
ence at the 15th or Bath meeting in 1888, 1 explained the petrographic
reasons which had led me to conclude after a careful study of a large
number of specimens that the rocks forming the nucleus of the island of
Cuba were Archean. I also gave reasons why I considered it a not un-
reasonable inference that Hayti, Jamaica, Porto Rico, and the Wind-
ward islands, as well as Yucatan and Florida were likewise provided
with Archean nuclei; and that this implied a branch or fork of the Ap-
l)alachian chain and the enclosure of the Caribbean sea by an Archean
wall now largely broken down.
4n a paper recently issued by Dr. W. Bergt, on the geology of San
Domingo (Zur Geologic von San Domingo; Abhandlungen der Natur-
wissenschaftlichen Gesellschaft "Isis" in Dresden, 1807, Heft, H) the
author fully confirms the suspicion with regard to San Domingo and
agrees with my earlier statement of the probabilities of this structure.
These views received the attention of Bonney, R^nard and all the
petrographers who attended the 5th International Geological Congress,
md the 15th Session of the B. A. A. S. in 1888, and I believe the petro-
Correspondence. 2 5 1
graphic and structural arguments on which these were based obtained
the endorsement of all of them. This later confirmation by special
study of a part of the field then not explored, is interesting in itself and
in relation to the geological history of the Continent.
Dr. Bergt criticizes unfavorably Gabb's geology of San Domingo.
Persifor Frazer.
The Interglacial Deposits of Northeastern Iowa. [Ab-
stract.]* Interglacial deposits occur at two horizons in the glacial
series of northeastern Iowa. The first is the pe;^t and forest bed
which, so far as this region is concerned, was first brought to the at-
tention of science by the writings of McGee. The second is the Bu-
chanan gravels of Calvin.
Owent was the first geologist to refer to the drift of northeastern
Iowa. He was much impressed by the great bowlders strewn over the
surface, and expressed the belief that they had probably been trans-
ported to their present position by floating ice. White discussed the
drift more fully, and recognized its glacial origin, but the time had not
yet come for recognizing the complex nature of the Pleistocene deposits
and hence the numerous problems with which more recent investigators
have been chiefly concerned were not considered.
It remained for McGee to introduce methods of investigation that
finally furnished the key to the interpretation of the complex Pleistocene
system. He pointed out in numerous contributions to geological liter-
ature that the drift was certainly not single, but that it embraced
at least two distinct sheets ot till.§ He insisted that the in-
terval between the two glacial invasions was one of enormous
length. He regarded the forest bed as lying between his lower and up-
per till. He furnished criteria for discriminating the two till sheets by
their color and contents. He it was who led the way to a satisfactory
classification of the Pleistocene bed of this part of the Mississippi val-
ley.
Recent investigations show that McGee's lower till embraces two dis-
tinct drift sheets, and that it is between these two that the forest bed
invariably lies. Three drift sheets, therefore, are recognized in north-
eastern Iowa, and in recent literature referring to Pleistocene geology
they are known respectively as Sub-Aftonian, Kansan and lowan. No
forest material has been observed between the Kansan and lowan, but
in this situation there occur extensive beds of stratified sand and gravel.
The forest bed between the first and second drift sheets is frequently
I'ccompanied by beds of peat from an inch or less to three or four feet
in thickness. The peat beds often cover areas of considerable extent.
•Read before tlie Iowa Academy of Sciences, Dec, l^y?.
iReport of a Geolojfical Rc^connoissance, etc., p. 69, 184ti.
Report of a Gool. Sur. of Wits.. Iowa and Minn., p. 144, 18.V2.
^Report on Geol. Sur. of Iowa, pp. 82-102, 1870.
BMcGee's observations on the drift of tliis rt'trion is well summed up in "The Pleis-
tocene History of Northeastern Iowa," U. S. (ieol. Sur., Ehnentli An. Rpt., pp. 18;*-
577,18«1.
252 The American Geologist AprU, i898
Where peat is absent at this horizon there is often evidence of an
ancient soil, humus stained and weather stained as is the case with
modern soils. This soil, peat and forest horizon is correlated with the
Aftonian interglacial deposits of southwestern Iowa. It has been en-
countered in hundreds of wells and has been revealed in not a few
instances in railway cuttings. Its development in the great railway cut
at Oelwein, Iowa, is discussed in the Proceedings of the Iowa Academy
of Sciences,* and its relations to the Sub-Aftonian and Kansan till
sheets are well set forth in the extensive series of well sections published
by McGee.t
Buchanan gravels were first recognized as a distinct interglacial
deposit at the gravel pit of the Illinois Central railway in section 32 of
Byron -township, Buchanan county, Iowa. A description of this type
locality was read before the Iowa Academy of Sciences two years ago
and was published in the American Geologist. X The beds to which the
name was applied consist of stratified sand and gravel. The bedding is
in places oblique, showing action of strong currents. Scattered through
the deposit are bowlders ranging up to twelve or fifteen inches in diame-
ter, and many of the bowlders still retain perfectly the facets and
scratches due to glacial planing. They may have been transported by
floating ice. At all events they have not been rolled or abraded to any
appreciable extent.
The materials composing the Buchanan gravels have been derived
chiefly from northern sources. Furthermore they possess the charac-
teristics of pebbles and bowlders found in the Kansan drift. Certain
granites and other rock species are completely decayed, and crumble
to fine particles on the application of slight force. Finally the gravels
are exceedingly ferruginous and weather stained, particularly near the
top of the deposit, the weathered portion taking on a characteristic rusty,
reddish brown color.
At the typical locality the Buchanan gravels rest on blue till of Kan-
san age and are overlain by a bed of fresh lowan till from two to eight
feet in thickness. The lowan till contains a great number of large
sized, light colored granite bowlders, some of which are perched on the
brink of the pit, while some have been undermined and have fallen to
the bottom. The gravels here clearly lie between two sheets of till.
The weathering, oxidation and decay the materials have suffered afford
in some degree a measure of the length of the interglacial interval. Two
years ago it was the current belief that the Pleistocene deposits of Iowa,
except in the area occupied by the Wisconsin lobe, contained a record
of two ice invasions and of two only. Accordingly the Aftonian gravels
and soil beds which had previously been observed in Union county were
assumed to lie between McGee's lower and upper till, and since the
Buchanan gravels plainly occupied what seemed to be a similar position,
they were first referred to the Aftonian stage. Our knowledge of Pleis-
*Vol. IV. pp. 54-68 18»7.
tPleistocene History of Northoastem Iowa, pp. 515-540.
$Vol. XVII, p. 76. Feb. 1896.
Correspondefice. 253
tocene deposits has moved with tremendous strides during the past two
years. A few points only can be noted. First, Bain showed that the
till overlying the Aftonian beds was Kansan; the lower till of McGee,
and not the low^an as had been assumed. This observation necessitated
adjustment of views previously held. It added a new drift sheet to the
known glacial series of Iowa. It demonstrated that the Aftonian and
Buchanan interglacial beds belonged to different horizons. Before that
adjustment Chamberlin* had published his classification of American
glacial deposits which recognized only the Kansan, lowan and Wiscon-
sin glacial stages, with two interglacial stages, the Aftonian being re-
ferred to the interval between the Kalisan and the lowan. Bain's demon-
stration of the true position of the Aftonian left the Buchanan gravels
as the only recognized deposit, so far published, representing this inter-
val, and the term Buchanan offered itself as a convenient designatioi;
for the second interglacial period. In the meantime Levcrettf was
pushing investigations on a sheet of till younger than the Kansan, but
much older than the lowan, and furnishing proof that the enormously
long interval between the Kansan and lowan ice invasions was not a
unit, but comprised three distinct stages of the glacial series. One of
these stages, the lUinoian, was glacial, the other two interglacial. When
therefore in 1896 ChamberlinJ revised his classification of glacial deposits,
there were five drift sheets to be recognized in place of three. The
Aftonian beds were assigned to their true place beneath the Kansan,
and the term Buchanan was used for the second interglacial stage.
The Buchanan gravels are connected genetically with events imme-
diately following, or intimately attending the withdrawal of the Kansan
ice. The materials were evidently derived directly from the Kansan
drift. So far as their deposition is concerned they belong to the very
beginning of the interglacial stage following the Kansan. They are
much more widely distributed than was at first supposed. They are ex-
posed, in cases with a thickness of thirty feet, at scores of points in each
of a number of counties examined, and sometimes hundreds of acres arc
embraced in a single continuous area. Within the region invaded by
lowan ice they are usually overlain by lowan till with characteristic
lowan bowlders strewn over the surface. In the northeast corner of
Delaware county, and at other points within the Kansan area but out-
side the margin of the lowan drift, they are overlain by loess.
The use of the term Buchanan as a name for an interglacial stage
is open to criticism. It came into use tentatively before the recognition
of the Illinoian drift, as a stage distinct from either Kansan or lowan,
had been published; when the whole period of time between the retreat
of the Kansan, and the invasion of the luwan ice was supposed to be
a single, uninterrupted interglacial interval. It was first used in the
precise sense in which the term Aftonian was originally used, and as a
•Jonr. of Geol. Vol. Ill, p. 270, April-.Mny, I.S75.
The Great Ice Age, Jamon (^'ikif, 3il cni., ni». 724-774, 1895.
f Levorett had reco^iized the Illinoian drift as the representative* of a div<;tinct
1,'lacial stage as early a^ 1.S94, hut tho fact \va» not published until 1886.
{Jour, of Geol., vol, IV, p. 874, OcU-Nov., IhuS.
254 ^^ American Geologist. April, iws
substitute for that term when it was shown that the Altonian soils and
gravels preceded the Kansan stage. Since the recognition of the lUi-
iioian glacial stage the term has been used for the interval following the
Kansau in publications by Chamberlin, Calvin and Scotl. No great
objection to its continued use can be urged. In fact it is much to be
desired that names once introduced should remain undisturbed; but it
in^y after all be a decided gain to Pleistocene geology to select a name
for tlie interval between the Ksnsan and the Illinoian from some local-
ity where true inierglacial deposits are clearly intercalated between
Kansan and Illinoian sheets of drift. Samuel Calvis.
The Weathered Zone (Yarmouth) between the Illinojas
AND Kansan Till Sheets. [Abstract. [* The extent of overlap of
the Illinois glacial lobe upon the Kansan sheet of drift deposited by a
neighboring tobe on the west is briefly considered. The question of the
occurrence of a sheet of drift of Kansan age in the series deposited by
the Illinois lobe is left open.
The name Yarmouth, taken from a village standing on the marginal
lidge of the Illinoian till sheet in southeastern Iowa, represents the lo-
cality where the break between the Illinoian and Kansan till sheets was
first recognized by ilie writer (November, 1888),
The sections showing this break are presented, there being in one
section a peat bed 15 feet in depth containing much woody materia)
and also bones of the rabbit and skunk. The latter were brought to
notice by Mr. W J McGee in the Eleventh Annual Report of the U. S.
Geo logical Survey.
Natural exposures and well sections along the belt of overlap art'
presented which show that the development of a soil horizon and tin-
leaching of the Kansan till suriacc is about as marked as in the Sanga-
mon weathered zone. These exposures extend from Davenport. Iowa.
southward to the vicinity of Quincy, Illinois, distance of fully 100
miles, and are found at frequent intervals throughout the portion of
Iowa covered by the Illinois glacial lobe. Fortunately there was suffi-
cient overlap of the Illinois lobe upon the Kansan till surface to make
clear the interpretation that the Illinoian is a markedly younger sheet
than the Kansan. This difference in age was suspected to occur from a
comparison of the maturity of valleys in the two districts; but the testi-
mony of the weathered zone preserved beneath the Illinoian till sheet was
necessary to confirm it.
The Weatherki) Zosie IS,
ASI> Ii.LiNotAN Til. I, Sheet.
<>f the Illinoian till sheet, the
Buchanan to the interval betw
,Ls follows:
■"Manifestly the deposition
■Ki.Hc( b-fi>re IW !..«■« .\™Hom> ..
Correspondence, 255
small part of the time between the Kansan retreat and the lowan ad-
vance. Unless therefore the subsequent weathering be included under
this name, the Buchanan does not fill an interglacial stage. Were there
no lUinioian glacial stage to break the continuitj' of interglacial condi-
tions from the Kansan to the lowan stage of glaciation it would seem
unnecessary to introduce other names. But in view of this glacial inter-
ruption there seems need for names which will stand for the weathered
zones above and below the Illinoian till sheet It is for this reason
that the name Sangamon is here proposed for a weathered zone between
the lowan loess and the Illinoian till sheet The name Yarmouth is
introduced in an accompanying paper for the weathered zone between
the Illinoian and Kansan till sheets. The name Buchanan may still be
retained with the significance given it by Prof. Calvin; and if weathering
be included may perhaps be used to cover the time involved in the two
interglacial stages and intervening glacial stage which occur between
the Kansan retreat and the lowan advance."
The name Sangamon is taken from the county and drainage basin
of that name in central Illinois where exposures showing the break
J>etween the lowan loess and Illinoian till were first discussed in print.*
At the type locality the break is filled to a large degree with the accumu-
lation of a bed of peaty muck. This is a feature which characterizes a
large part of the Sangamon drainage basin and is one that is perhaps
more likely than any other interglacial product to draw attention. It
is not, however,* the most common and widespread phase. A much
more common phase is a reddish brown leached surface of the till sheet
This appears to have been developed in all places where there was good
drainage. The black muck indicates poor drainage conditions, and
where it is present the reddened zone is weakly developed. Leaching
of the surface of the calcareous till is found to have reached an average
depth of about six feet prior to the deposition of the loess. The loess
deposition is referred chiefly to the lowan stage of glaciation: the
change in the Illinoian surface therefore took place between these two
pflacial stages. Several noteworthy exposures are cited, in one of which
peat reaches a denth of 13 feet, and in several of which a soil and leach-
ing fully equal to that commonly displayed by the Wisconsin or the
lowan may be seen. A kodak view of one exposure taken at a dis-
tance of about one-fourth mile shows the Sangamon soil clearly.
Valley excavation during the Sangamon interglacial stage is touched
upon briefly. It is shown that conditions were favorable only for the
])roduction of shallow valleys, but that these valleys reached in some
cases a breadth much greater than the modern valleys of the same
streams. Frank Leverett.
The Aftonian and Pre-Kan.san Deposits in Southwestern
lowA, [Abstract.]t The Aftonian deposits of southwestern Iowa have
peculiar interest in that within the area is the type locality for the
Aftonian. So far neither the drift of the region nor the Aftonian as a
•A. H. Wcitthen, Geology of Illinois, vol. V. 1S73. pp. :«>8-a09.
^Soad before the Iowa Academy of Sciences, Dec. 1897,
2s6 The American Geologist. April. i»<
unit has received a general discussion. It should be remembered that
the exposures of the Aftonian and the sub-Aftonian are scattered; that
their importance was unsuspected until quite recently; that in ihe nature
of things the phenomena may be expected to be somewhat illusive and
that but little of the area has received detailed study. In view of these
facts the present must be taken as a preliminary statement only and
subject to considerable future revision.
The Atton-Thayer exposures were visited by McGee and Chamber-
lin in company, and the evidence of an inierglacial interval here, in con-
nection with the facts derived from a study of other portions of the Mis-
sissippi valley, was considered sufficient to warrant the reference of the
beds to Iwo distinct periods of glaciation. With a wise conservatism
the two periods were assumed lo be the same as had been demonstrated
in northeastern Iowa, and accordingly in the nomenclature eventually
proposed by Chamberlin* the upper drift at Afton was considered to
be the lowan, and the lower the Kansan. The Aftonian beds proper
were considered to represent the interval between the Kansan and the
lowan. It is important to note that in the original paper by Chamber-
lin tjje term Aftonian was not applied to the gravels which form so
conspicuous a feature of the Afton-Thayer sections. These were con-
sidered to represent rather kame-Iike accumulations upon the surface
of the older drift sheet. This distinction has not been always clearly
observed.
The Afton-Thayer outcrops are for many reasons thfe most important
of those bearing on the question of an interglacial interval in south-
westein Iowa and will be described in some detail. Preliminary to
this it is desired lo examine briefly what sort of evidence may properly
be required to establish the presence of two drift sheets. In southern
Iowa the most important criteria have been found to be forest beds
..nd buried soils, leached horizons, ferrtiginaled lones ("ferretto hori-
zons"), water-laid beds, topographic changes, and the physical charac-
ter of the till. The cumulative value of this sort of evidence is believed
lo be important.
The A/ton- Thayer Exfiosiirrs.
The Aftonian beds are not positively known lo occur in or immedi-
ately adjacent to the city of Afton; the latter is, however, the best
known place near the original exposures. The beds are seen well ex-
posed at three abandoned gravel pits located three to six miles east of
Afton proper. These are (i) between Afton Junction and Talmage:
(■2) about one mile southeast of the Junction on the south side of Grand
river; (3) about three-quarters of a mile west of Thayer on the south
side of the C, B. and Q. railway. For convenience the*e will be called
ihe Afton Junction, Grant
Afton Junction pits show t!
gravels, with certain buried
river exposure shows the 1
CorrespondeTice, 257
iween. The Thayer exposure shows the gravels and the overlying drift
with certain sands and fine clays between.
Afion Junction, The pits at this place are about 1,500 feet north
of the railway station on the west side of the Chicago Great Western,
They have been opened alopg the sides of a small stream running
east and emptying into Grand river. The north side of the pit is
bilobate, the minor lobe being to the east and not directly in line with
the main face of the pit. The two lobes in fact form an arc of a rude
circle rather than a straight face. Between the two lobes is a small
stream which has cut down to, but not through, the gravels. The
main face is about 1,000 feet long and has a maximum hight of probably
seventy feet. The minor or east lobe is about 400 feet long and 60 feet
high. The bottom of the pit, said to rest on "quick sand," is cut down
to about the level of Grand river bottom (1,030 A. T.). The stream is
here of the post-Kansan age. The section exposed at the main face is as
follows:
Feet.
Loess of the usual uplift or older typo characteristic of the
region Itt
Yellow boulder clay with upper portion much oxidized
letiched and highly colorad, lower portion running in-
to a blue with weathered joint cracks. Containing
much weathered material and planed and stri-
ated bowlders, Characteristic Kansan 30
Gravel, corase, cross-bedded, iron stained, cemented in part
into hard conglomerate ; made up to considerable ex-
tent of very badly weathered material. Manifestly an
old gravel 40
Down to the gravels this is the normal section for the region and
could be duplicated at hundreds of points. The ferretto zone is well
developed and its coloring is dark enough to show excellently in a pho-
tograph. The drift and loess are identical in every particular with that
found throughout southern Iowa and there can be no doubt whatever
that the drift is Kansan.
The drift shown in the east lobe is of the same character as that
overlying the gravels in the main face, and the identity of the two has
not been questioned so far as is known to the writer by any who have
visited the place. Among the latter may be mentioned Profs. T. C.
Chamberlin, Albrecht Penck, Samuel Calvin and S. W. Beyer. Prof.
G. F. Wright and others have seen the exposure, but their opinions on
this point are not known to the writer. The drift in the east lobe lies
at a considerably lower level than in the main face, extending in fact
down to the bottom of the pit. As the railway near the station just
cuts into the top of the gravel a few feet, this was, when first seen, in-
terpreted to mean that the gravels formed a kame-like ridge with a north-
west-southeast trend and that the drift had been laid over this ridge run-
ning down over its side. It was thought likely that there had been
some erosion whereby an eastern extension of the gravels had been
cut away before the drift of the east lobe was laid down, and that, ac-
cordingly, the position of the drift indicated, or at least accorded with,
258 The American Geologist, April, 1888
a certain time interval between the gravel and the overlying drift. Re-
cent studies fail to sustain this view. The Great Western railway com-
pany undertook to open up the gravels at the point near the* station
where they showed above the track. As the steam shovel travelled to
the north it was found that the gravel contained more and more clay
until ordinary bowlder clay was being handled and the work was
stopped. An examination of the east lobe of the old pit shows that
the same ti'ansition may be traced. In this drift faint lines of stratifica-
tion may be noticed running through the bowlder clay. So faint are
these in the portion some distance from the gravels that they were at
first entirely overlooked. Reexamination showed, however, that the
bowlder clay passes into the gravel and vice versa. This relationship
lias been somewhat obscured by the circumstances of the stream pouring
down at the contact; but, when a careful examination is made, the facts
are seen to be unmistakable. There is no evidence of erosion, nor are
there dynamic phenomena at the contact, such as might have been ex-
pected had the gravels been present and a later drift shetft pushed against
them. Indeed there is no contact, but rather a transition; that is, the
gravels are contemporaneous with the drift and of Kansan age. As
this is a point of some moment it may be mentioned that the Reynolds
ford gravels in Decatur county, doubtless the extension of those near
Afton Junction, show the same lateral transition into drift of presuma-
ble Kansan age.
At the extreme east end of the east lobe there is an exposure show-
ing the beds below the drift. This exposure is in a borrow pit made
in getting material for the railway fill. The overlying bed here is the
yellow clay of the Kansan. It is here so far from the gravels that it
shows no signs of stratification nor indeed anything to indicate that it
is anything more than the ordinary yellow clay of the Kansan. It can.
liowever, be traced step by step through the slightly stratified drift and
from that through the more distinctly stratified beds and so into the
gravel. Beneath the yellow bowlder clay there occurs a pebbleless clay
resembling the loess. Indeed one might imagine it to be the ordinary
drift-loess section of the region reversed and minus the ferretto zone.
In fact that is exactly what it is; a loess buried beneath yellow bowlder
clay. In all important respects it so closely resembles the ordinary
upland loess that the two could probably be discriminated only with
difficulty. As the loess shows under the stratified beds at one point in
the pit several hundred feet from this exposure, it is clearly not to be
explained as a hillside creep. Indeed it is probable that the "quick
sand" found beneath the gravel is this loess.
Grand River Section. The exposure on the river proper is about
one mile away and one exposure is in view from the other. Between or-
dinary erosion has cut away the connecting beds; but looking across the
amphitheatre the connection is obvious. This section is the only one in
the region showing the lower till and is accordingly of exceptional in-
terest. The full exposure shows the loess Kansan drift, and gravels
as seen elsewhere. Beneath them are the following beds:
Corre$pond€7tce, 259
Fejt.
Boulder clay (sub-Aftotiian), a blue black clay non weath-
ered at top and coming: into sharp contact with the
ferruglnatedgravolSfContaining mainly small pebbles,
predominantly of vein qaartz but with a fair propor-
tion of grrauite. Many if not most of the pebbles fresh
and hard 40
Red and blue shales uf Missourian stage 20
The peculiar physical character of the lower bowlder clay. is striking.
It is dense, and breaks usually in flakes rather than joint blocks. It
is of a strikingly dark color. There are few joint cracks and these
show no special signs of weathering. The sharpness of the contact
between the gravels and the bowlder clay with the presence of many
hard pebbles indicates apparently one of two things (i) either this
lower clay was not exposed to surface action before the gravels were
laid down or (2) it was so vigorously eroded immediately before the
deposition of the gravels as to cut away all evidence of former sur-
face exposure. The balance of probabilities between the two will be
discussed later.
Thayer Section, The Thayer section is of interest since it seems
that here the evidence of two drifts was first detected. The section
a.s now shown, varies a little from point to point in the pit. but a repre-
sentative exposure shows the following beds:
Feet. Inches.
9. Blacksoil : 6
8. Reddish gravelly clay (ferrel to) 1
7. Yellow bowlder clay becoming gravelly below
and containing quartzyte. greenstone and
granite ; flat^tenod and striated pebbles with
lime concretions 10-20
6. Fine sand 1 6
5. Drab to blue pebbly clay with sticks and bits
of undetermined wood 4
4. Fine sand 3
3. Drab pebbly clay as above 12
2. Fine sand 2
1. Qravel as seen befon*, stratified and crf>SK-bedd-
od ; pebbles mainly less than 1 V% inch in
diameter but with some largo bowlders.
Material of the usual Kansan facies, much
weathered and highly colored 15-20
Stimmarizing the above we have the loess and yellow and blue clay
phases of the Kansan with the underlying gravels. The blue clay phase
of the Kansan is unusual in the presence of interstratified beds of fine
sand and the abundance of woody material. It is dark and might read-
ily be taken for a buried soil, but it is believed that this is not the true
interpretation. The exposure does not now show the beds as seen by
Messrs. McGee and Chamberlin. The same horizon as exposed some
feet eastward shows merely the blue black pebble clay as mentioned
above. The presence of so much wood in the bowlder clay is difficult
to explain unless it be regarded as basal, and the beds as now exposed
have no thoroughly satisfactory explanation on either hypothesis. Re-
garding the clay, however, merely as the blue clay phase of the Kansan
^'^^
26o The American Geologist, April, 1888
the whole series of phenomena become concordant and consistent and in
the question of the presence or absence of a distinct sub-Aftonian till
sheet the beds to be considered lie all at one horizon — below the gravels.
There are certain concordant phenomena which must be kept in mind
in framing a h)rpothesis to explain the Afton exposures. The gravels
themselves are exposed at several points. A peat bed is found in wells
near Afton, and forest beds are found near Lamoni, Murray, Fon-
tanelle, Washington, Sigourney, and at various points in Taylor county,
Iowa, and Harison county^ Missouri. The peculiar blue black bowlder
clay is occasionally exposed throughout the state. There is a gumbo
between drifts at points in Clarke and Decatur counties, and an old
soil shows on Grand river. The exposure near Hastie, in Polk county,
is considered very significant.
Summary,
In considering the conclusion to be drawn from the evidence now in
hand the remarks relative to the value of the various lines of evidence
should be kept in mind.
First. It is submitted that there is widespread evidence of buried
forest and peat beds in the region. It is admitted that nothing of im-
portance bearing on the character of this flora as regards climate is
known. It is further admitted that these notes on forest beds have not
been sifted and much of the evidence is of uncertain value. It is on
the other hand to be noted that certain of the beds are well attested
as to position, occupying a horizon fitting well with the hypothesis of
two drifts and that some are of a thickness worthy of consideration.
Tpon the whole, however, the argument from forest beds probably has
little independent value.
Second. Buried soils have been shown to be not unknown, though
the value of the evidence derived from them is uncertain.
Third. It has been impossible so far to apply the ordinary tests
based on leached and ferretto zones to the sub-Aftonian.
Fourth. Waterlaid beds are present at several points at the Aftonian
horizon. In Polk county they are believed to be notably earlier than
the overlying drift. At Afton they seem to the writer to represent
kame-like aggregations made during the advance of the Kansan. In
general the waterlaid beds are such as might have been formed by
agencies closely connected with the ice. The possible exception is the
buried loess at Afton Junction which, however, would only necessitate
a considerable change in the vigor of deposition between the time of its
formation and the laying down of the overlying gravel.
Fifth, Since the presumed sub-Aftonian drift is thought to be
wholly covered by the Kansan and is certainly known to be in the
region studied, there is but little chance to contrast the topographic
development of the two drift surfaces. Relative to erosion in the
period between the two drift sheets it may be stated that the Hastie ex-
posure strongly favors such a supposition. In considering the matter
whether or not the exposures near Afton also favor such an hypothesis
Corresponderue. 261
the presence of the buried loess at Afton Junction should not be for-
gotten. This loess is of the old type, and if, as seems probable from
several lines of evidence, the older loess or white clay owes its peculiar
properties as much to secondary change as to conditions of original
deposition, it alone would show a considerable time interval. At the
Grand river exposure it will be recalled that the upper surface of the
lower drift showed apparently no signs of either loess or weathering.
One would hesitate long before basing any argument upon a local dis-
tribution of such loess as occurs in northeastern Iowa, but it is not so
hazardous to use such an argument when discussing the older loess.
The latter is uniformly widespread over the surface of the Kansan and
Illinoian in southern Iowa. Its character gives one some confidence in
assigning to water a considerable part in its formation and, inasmuch
as the buried loess is of the same type as that now found over the up-
land, it seems well in accordance with what conservatism demands to
expect it to have at least a considerable distribution. Certainly we
would look for its presence in the Grand river exposure scarcely a mile
away. Its absence then becomes . a legitimate argument favoring
erosion before the gravels were laid down. One might suggest that
this erosion was due to the ice except that in that event one would
expect till and not water-laid beds to be the first deposits. Further-
more, while we are becoming able to understand how a glacier may
deposit over soft beds without disturbing them, we have as yet no case
of glacial erosion of unconsolidated beds leaving as sharp and un-
marked a surface as that of the top of the till at the point in question.
If then erosion be granted it must be held to have been pre- Kansan, and
in view of the freshness of the underlying till, it must have been consid-
erable. Upon the whole this is believed to be the best explanation of
the phenomena.
Sixth. It has been shown that there are exposures in the region
of a drift of peculiar physical type; that this drift is wholly unlike any
known phase of the Kansan, and that in every instance there are some
independent phenomena favoring the hypothesis that it is distinctly older
than the Kansan. Whatever one may think of correlations based upon
physical characters, these facts are certainly of some significance.
Furthermore the same facts are true of the known exposures of the
presumed pre-Kansan drift at Muscatine, Oelwein, Albion, and indeed
throughout the state.
General conclusion. It is believed that the argument for a pre-Kan-
san drift sheet derived from erosion is strong and that it has independent
value. The arguments from other sources tend to greatly strengthen
it, and the cumulative force of the whole is believed to be sufficient to
put the burden of proof upon those, if any, who would attempt to deny
the existence of ore- Kansan drift. All would, however, probably agree
to the statement which the writer believes warranted by the evidence
in hand, and which he expects future investigations to amply confirm,
but for anything beyond which there is probably as yet no sufficient
262 The American Geologist. Apni, i8et>
evidence, that there are in Iowa traces of a drift sheet older than thr
Kansan and separated from it by an unknoimi but probably considerable
interval *
It may be mentioned in conclusion that it has been suggested, nota-
bly by Chamberlin,* that a complete series of deposits recording a
glacial period should theoretically include a series of early minor ad-
vances culminating in a period of maximum glaciation, followed by a
second series of advances of decreasing intensity. We have for some
time faced the anomaly that the earliest glaciation of which we had
record was that of showing the maximum extent of the ice. The pre-
Kansan fills in the gap and answers apparently to one of these earlier
and minor stages of advance. Additional work along the extreme drift
border may possibly prove that the pre-Kansan extends out beyond the
limits of the Kansan, but this is considered improbable. It is to be
noted that according to the theory there should be more than one pre-
Kansan advance and partial retreat of the ice, just as we have several
post- Kansan ice sheets. These earlier drifts may oj may not have been
separated by notable intervals as in the case of the later drifts. It is
quite possible that the pre-Kansan we now know of is not all one thing,
and for this reason, as well as the incompleteness of our knowledge .of
it, it seems best that this earlier drift should not be given a definite for-
niational name, certainly not until more is known of it. For the pres-
ent, the term pre-Kansan may be used, and just as pre-Cambrian, in a
much older portion of the geological column has come to have an ac-
cepted meaning, it is believed that the term will be valuable. The pre-
Kansan of Iowa may or may not belong with the Albertan of Dawson.
It may be older or younger. Probably we shall never know very much
about its divisions, though we may justly expect to know much more of
its distribution and character. It should be noted that the original cor-
relation of the forest bed of eastern Iowa with the Aftonian deposits
proves now to be essentially correct, since the former includes deposits
hotli above and below the drift now known as Kansan. Possibly
further study may indicate the advisability of a return to original nomen-
clature, though that outcome is not thought to be probable.
H. Foster Bain.
Some Pr?:(;lacial Soils. [Abstract.lt In the rc^non south of tht-
Wisconsin driftlcss area an old soil is occasionally found under the
Kansan 'drift, generally resting on bed rock, and often associated with
laminated, water-bedded clay and other silt. An exposure of such a
soil occurs under a bluff of drift in the southern part of Muscatine.
I(jwa. The material here is dark brown in color, mottled with small
Mack fra^iiunts of vegetable tissue. The upper part is a dark mucky
(.lay. The whole bed is only two or three inches in thickness. It lies
below what appears to be pre-Kansan drift. A similar bed was un-
roNcrcd on the east side of Eastern avenue at Davenport. Iowa. This
*(iroat Ico Ako i(T(Mkii»>, p. 7:i6. 1.h<j5.
tRcad boforo tho Iciwa Acadomy of Sciences, Dec. \Wi.
Correspaiidetice. 263
bed is somewhat darker than that at Muscatine. At Rock Island, Illi-
nois, the same bed has been encountered in several wells. In one of
these, near the crossing of Thirty-fifth street and Seventh avenue, the
materials penetrated consisted of loess, apparently two sheets of till, silt
varying from a black to a grayish loess, with small gasteropods, and
then a greenish, sticky clay containing fragments of the bed rock, but
apparently no Archean pebbles or bowlders. This latter clay was ^-^^
feet in thickness and rested on shales and clays of the Coal Measures.
It seemed to be residual material of preglacial age. The silt and muck
above it contained fragments of wood, one of which measured nearly
two feet in length. Silt of the same and in the same position, but oxi-
dized and without fragments of wood, has been exposed in grading some
of the streets near by. On Thirty-ninth street it contained the follow-
ing fossils: Helicina occulta Say, Pupa alticola Ingersoll, Pyramidula
striatella Anthony and Succinea avara Say. Similar deposits, without
fossils, occur under the drift in the bluffs east of Cordova, IlHnois, and
in. the northern part of Clinton, Iowa. At the latter place they are
finely laminated and are associated with a peaty or soil-like layer. A
deposit which appears identical with the loess-like silt on Thirty-fifth
street, Rock Island, is found underlying till on the east line of section
12, T. 17 N., R. I W., south of the city, and another occurs in the bluffs
tjf the Mississippi river in the west end of the county. At the first of
these localities the deposit rests on Coal Measures and contains the fos-
sils already mentioned as occurring at Thirty-ninth street. At the ex-
I'Osure in the west end of the county the underlying beds are not seen.
The total thickness of the overlying drift is about 100 feet. Shells are
abundant, and according to the determinations of Dr. W. H. Dall they
include Helicina occulta Say, Hclicodiscus lineatus Say, Limncea hunnlis
S^iy.Pupa armifert} Say, Pyramidula perspective Say, Pyramidula striat-
flla Anthony, Strobilops labyrinthiea Say, Succinea avara Say, Succinea
luteola Say, Polygyra, sp,. Vitrcea arborea Say.
These loess-like deposits have a bluish green color in fresh expos-
ures, but one season of weathering gives them a reddish gray hue to
the depth of one or two feet, and then their resemblance to the loess in
color as well as in structure is quite marked. Even the tubular, fer-
ruginous concretions of the latter deposit appear.
The precise relation of the soil beds to this deposit and to the lamin-
ated silts with which it seems to be assocfated, and the relation that
the two latter have to each other, can not be fully made out from the
known exposures. In the well on Thirty-fifth street there seemed in-
deed to be two soil horizons. The section under the Kansan till was as
follows, beginning above:
1. Black .sticky muck with lar^'c fraKment.s of wood 4 feet.
2. Loo88-Iiko, aa!i colored material, with pulmonate fossils. 8
:i Black Muck i
4. Residual clay full of li>cal r(»ck fraKments ^
5. Coal M&asui-e» (Exposed.)
41
It
t.
^x
»»n' r
TTr-
l-T^. 1'
r^'rrSair
/ / ^•
Ttacr
' * y. M
:3i :i
-'^ «..
' .'1"^'i* Tr
- ^.-r
> ^* *. 1. f
Personal and Sckntijic Nezvs, 265
be fully appreciated by those who personally visit the fields.
In his more strictly geological work the constructional
materials received most attention. While in Missouri he
mapped, in conjunction with Dr. Haworth, large areas of the
crystalline district in the southeastern part of the state; located
and took copious notes on a large number of iron deposits,
being associated with Mr. Nason in this work; and collected
much information on the clays and building materials, which
was intended finally to form an elaborate report on those sub-
jects. In Iowa his main efforts were directed towards collect-
ing data for an exhaustive report on the clays of the state.
The vast amount of information attained regarding the de-
posits, their character and properties, and the condition of the
industry attest the vigor with which his work was prosecuted,
and the enthusiasm which the work aroused in him. The
work in connection with the U. S. Geological Survey was
entirely topographical, t1:e fields of o])eration being in Mis-
souri, Minnesota and Indian Territory.
Mr. Lonsdale contributed a number of articles of great
value to the trade journals. His more strictly scientific papers
have appeared in the proceedings of the learned societies and
the reports of the geological surveys. The beautiful topo-
graphic map of the Mine la Motte district and a part of that
of the Iron Mountain area, Missouri, are his work. The
"(jeology of Montgomery County, Iowa" is the first detailed
geological work ever undertaken in western Iowa. The main
work of his life on the "Clays of Iowa,'' which would have
occupied a large volume, was not finished at the time of his
death.
Mr. Lonsdale was a member of a number of scientific and
engineering societies, and was usually in attendance at the
meetings, in which he took an active part. c. r. k.
Government P^xplorations in Alaska. — The work
in .Alaska during the coming summer, under the direction of
the United States Geological Survey, will be divided between
f(nir parties, each of which will conduct geological and topo-
g-raphical investigations. The arrangements for the parties
are in general charge of ^Tr. G. C. Eldridge. The parties are
as follows: (i) Mr. G. C. Eldridge, geologist, in charge, and
Mr. Muldow, topographer. They will explore the Sushitna
drainage. (2) Mr. J. E. Spurr, geologist, in charge, and Mr.
Post, topographer. They will explore theKuskc kwim drain-
2ig^- (3) Mr. Peters, topographer, in charge, and Mr. A. H.
Brooks, geologist. They will go up the White river and
down the Tanana river. (4) A topographical party in charge
of Mr. Barnard. This party will make a more detailed sur-
266 The American Geologist. April, i898
vey of the Forty Mile district. Mr. Arthur C. Keith, geolo-
gist, will cooperate with Mr. Barnard's party in this district.
In addition to these parties two geologists from the United
States Geological Survey, Messrs. F. C. Shraeder and W. C.
Mendenhall, will accompany expeditions sent out by the War
department. It is expected that the first of these gentlemen
will go up the Copper river, and that the second will proceed
inland between the Copper and Sushitna rivers. All of the
above mentioned gentlemen expect to return to Washington
the coming fall.
New York Academy of Sciences. Section of Geology
and Mineralogy, March 21st, 1898. The paper of the even-
ing, illustrated by lantern, was by Dr. Heinrich Ries, entitled,
"The Clay and Kaolin Deposits of Europe." Dr. Ries
sketched briefly the geographical distribution of the kaolin
deposits, and their relation and comparison to similar deposits
of America. He then gave special attention to the deposits
of Great Britain, Belgium, Denmark, Germany and Austria,
and mentioned briefly those found in other regions. He de-
scribed particularly the deposits of Cornwall, which are found
in association with veins of tin in granite areas, where it is
supposed that the feldspar has been changed to kaolin through
the influence of fluoric fumes rising from below. These
products are very pure, containing 97^ per cent of clay sub-
stance. He also spoke of the ball plastic clays found in south-
western England, which occur in lenses in large beds of sand,
and are used to mix with non-plastic kaolins. Refractory
clays are found in England and Scotland in the Carboniferous
rocks and are worked by underground mining. Impure clays,
used for bricks, are particularly found in the vicinity of Lon-
don. The Staffordshire blre brick. Fuller's earth and Bath
brick deposits were sketched briefly, and the technological
treatment in Great Britain, Genrany and the United States
was compared. The latter part of the paper was devoted
to a rapid summary of the position, quality, uses and manner
of mining of the famous clays of Bornholm, Denmark; of the
Glasspot clays of southeastern Belgium \ of the kaolin deposits
of Limoges, France, and the deposits of Prussia.
Prof. Henry F. Osborn described the progress made this
year, through international effort, in correlating the larger
divisions of the fresh water Te rtiary deposits of Europe by a
study of the vertebrate remains.
Prof. James F. Kemp was elected chairman of the section,
and Dr. Heinrich Ries secretary, for ensuing year.
Richard E. Dodge, Sec'y.
FREDERICK HAWN.
THE
AMERICAN GEOLOGIST
Vol. XXI. MAY, 1898. No. 5
MAJOR FREDERICK HAWN.
By G. C. Broadhead, Columbia, Mo.
[Plate XVI. J
Forty years ago the name of Maj. Frederick Hawn was
often heard in geological circles. He was bom in Herkimer
county, New York, January 5, 18 10, and died in Leaven-
worth, Kans., January 31, 1898, aged 88 years. He was of
Revolutionary German stock, his grandfather, Conrad Hawn,
having been killed .in the battle of Oriskany. He devoted his
early life to civil engineering, and assisted in constructing
the first railroad in Pennsylvania, and in 1831 saw the first
locomotive placed on its track.
In 1835 he was engaged in railroad construction in Illi-
nois, but soon after settled in the town of Weston, Missouri.
In 185 1 he was engineer on the Hannibal and St. Joseph
railroad, but soon after was appointed by Prof. G. C. Swal-
low as an assistant on the Missouri Geological Survey, and
assigned to the duty of making an examination of the country
along and near the line of the Hannibal and St. Joseph rail-
road. He made partial examinations of twelve counties of
Missouri near the railroad line from the Mississippi to the
Missouri river. The report was published in Swallow's geo-
logical report of Missouri, 1855. It called particular atten-
tion to the lands and the valuable coal beds near the railroad,
and its circulation greatly assisted the railroad company in
268 The American Geologist, May, isoh
the sale of its lands, and thus enabled the company to com-
plete its road at an early day.
Soon after, Maj. Hawn assisted in the linear surveys in
Kansas. While thus engaged he took careful notes on Kan-
sas geology, being really the pioneer in that field, and
brought together a very interesting collection of organic re-
mains. These were brought to Columbia and carefully
studied with Prof. Swallow, ^nd on February 22, 1858, Prof.
Swallow, in a communication to the St. Louis Academy of
Science, announced the discovery of the Permian in Kansas,
and at the same meeting Prof. Swallow offered a paper for
publication entitled '*The Rocks of Kansas," by G. C. Swal-
low and F. Hawn. This was published in Volume I. of the
Transactions of the Academy, pages 173 to 198. In the same
volume of Transactions, pages 171 to 172, Maj. Hawn con-
tributes a paper on the Trias of Kansas. This was the first
announcement of such beds being found in Kansas.
The series of fossils collected by Maj. Hawn in Kansas
awakened great interest in western geology, and soon after
Meek and Shumard also published papers on the Permian.
Between the years 1865 and 1870 Prof. Swallow was state
geologist of Kansas, with Hawn assisting in the work. Swal-
low says (letter of Transmission, Jan. 8, 1866): '*Maj. Hawn
has given the survey the full benefit of his intimate and ex-
tensive knowledge of the state and its resources. His reports
are full of scientific and nractical information." Swallow's
geological report of Kansas includes Hawn's report of 25
pages, with brief notices of the geology of the counties of
Linn, Chase, Doniphon, Brown, Greenwood, Lyon, Butler,
( )sage and Morris.
In 1853 Lieut. E. H. Ruffner, corps of engineers U. S. A.,
under the direction of the war department, made a reconnois-
ance of the Ute country in southwest Colorado. Maj. Hawn
accompanied the expedition as geologist and meteorologist,
and Lieut. Ruffner, in his report to the war department, says
of Hawn, 'That Professor Hawn has been as faithful to his
trust as could be desired is undoubted, and that little has
escaped his eye is a natural consequence of his untiring in-
dustry. I speak decidedly in giving my testimony to the
efficiency of the geologist's assistant, L. Hawn. I beg to
Major Frederick Hawn. — Broadkead, 269
state that although I have slightly altered the form of the
geological report I have endeavored • to change nothing in
its sense." In his geologic work Maj. Hawn was assisted by
his son, Laurens Hawn.* Hawn's report accompanied that
of Ruffner's, and includes a geological reconnoisance along
the route, as well as a report on the Ute country, list of mines,
fossils, rocks and ores.
Maj. Hawn's letters to the eastern papers during the in-
fancy of Kansas assisted very much in drawing immigration
to the territory. Following his advice prospecting for coal
was done at Leavenworth, and a shaft sunk and coal obtained,
and now, for a number of years, Leavenworth has been a
distributing point for coal and the city has prospered.
Maj. Hawn, through life, was more or less a student of
science, his later life being chiefly devoted to meteorology,
and independently of others he showed conclusively that hot
air waves were not generated by surface heat in their path,
but by the bearing down or descending air evolving heat
by pressure.
Maj. Hawn was a quiet, modest man, and the later years
of his life were spent in retirement with his family, delighting
in his fruits and flowers. The day before his death he com-
pleted an article on meteorology for Colman^s Rural World.
Although he gradually became more feeble in body as he grew
older, yet his mind was bright to the last.
Geological Publications of Frederick Hawn.j
[Report on country between the Mississippi and Missouri rivers
near the line of the Hannibal and St. Joseph railroad.] Geol. Survey of
Mo., ist and 2nd Ann. Repts., pt. 2, pp. 121-136, 1855.
The Trias of Kansas. St. Louis Acad. Sci., Trans., vol. i, no. 2.
pp.171-172, 1858.
The rocks of Kansas. By G. C. Swallow and F. Hawn. St. Louis
Acad. Sci., Trans., vol. i, no. 2, pp. 173-197, 1858.
[Report on Brown, Doniphon, Chase, Linn, Greenwood, Lyon,
Butler. Osage and Morris counties, Kansas.] Geol. Survey of Kans.,
Swallow's Preliminary Report, pp. 97-122, 1866.
[Report on the geology of the Ute country, etc., in southwest Col-
orado] Report of reconnaissance in the Ute country, made by Lt. E. H.
Ruffner in 1873; pp. 59-89, 1874. ist session of 42nd Congress.
*Xow probate judge, Leavenworth, Kansas.
tPrepared by his son. Judge Laurens Hawn.
270 The American Geologist. May, \^>
GEOLOGY OF THE ST. CROIX DALLES. III.
By Charles P. Berket, Minneapolis.
(Plates XVII-XXI.)
Part III. PALEONTOLOGY.
# Chapter L Review of the Faiina^
Since the publication of the reports of Owen* and Hall^
upon this and neighboring localities, there have^been few ad-
ditions to the fauna of the lowest rocks of the upper Missis-
sippi valley. The most notable exception to this statement is
the work by Whitfield. t This period of comparative inactivity
is the result of the greater immediate demand for investigation
in other directions rather than any tendency to consider this
field exhausted. In this connection it is interesting to read
the words of Hall from his general summary (op. cit.) of the
faunas of this region. He says: "Whenever this locality, and
the region about it, shall be more fully investigated, we may
confidently predict that additions of much value and interest
will be made to the primordial fauna of the Upper Mississippi
valley." P. 180.
A protracted search in the last two seasons has revealed an
extensive group of fossils many of which are believed to be
undescribed. These forms belong to the Basal Sandstone
series and, in order that a better understanding of their re-
lationship may be secured, a summary of the species previ-
ously described from overlying strata is here added.
Mdgncsian Scries. The uppermost representative of this
scries within the district is the yit^n/^'?;/ sandstone. The follow-
ing^ species arc found in this formiition. ^
Btlltrophon atttiquatus Whitticld.
Pleurotoniaria {Holopca\ xTivr// (Whitfield) Sar.
Ophilrta sp. (?)
Miinhisotiia sp. (?)
Lifij^ii/ii sfontuifiii Whitfield.
O ft his pepina Hall.
Raphistotna ffiinnt'sohnsc (Owen) Sar.
Tryhlidium ( Mctoptonni \ barahucnsis ( Whitfield ).
Ai^nostits disparilis Hall.
*()\ven: Geol. Siirv. of Wisconsin, Iowa and Minnesota, 1852.
tllall: i6th Rep. N. Y. Mus. Nat. Hist.. 1863.
JWhitfield: An. Rep. Geol. Surv. of Wisconsin for 1877. Geology
of Wisconsin, vol. IV, 1882.
TWO GENERIC TYPES.
Ftg. I. Chellocephalus
FlK- 2. Hypseloconus r
Geology of the St, Croix Dalles, — Berkcy. 271
A. parilis Hall.
Aglaspis barrandii Hall.
Dicellocephahis osceola Hall.
Illcenurus quadratus Hall.
In addition to these, many fragments of trilobites of unde-
termined species are found. Osceola, Wisconsin, and Rapi-
dan, Minnesota, are well known localities. Within the district
besides the Osceola occurrence, there are a few trilobite frag-
ments to be found in the sandstone conglomerate mentioned
in a former chapter as the most northern outcrop of the
Jordan sandstone.
From the St. Lawrence shales the following have been
reported.
Dicellocephalus minnesotensis Owen.
D. pepinensis Owen.
D. spiniger Hall.
Lonchocephalus chippewaensis Owen.
Ptychoparia anatina Hall.
P, diademata Hall.
P. eryon Hall.
P, oweni Hall.
Lingula aurora Hall.
L. mosia Hall.
L. winona Hall.
Or this pepina Hall.
Euomphatus vaticinus Hall.
Raphistoma fninnesotense (Owen) Sar.
Serputites murchisoni Hall.
The principal localities from which fossils have been de-
scribed are Marine Mills, Trempeleau and La Grange moun-
tain.
The remarkable group of fossils from near Baraboo, Wis-
consin, referred to the Lower Magnesian by Whitfield*, evi-
dently, as suggested by Irvingt, belong to a lower horizon.
They will be discussed in more detail in another chapter.
The Basal Sandstone Series.
In Wisconsin to the southeast of this area the floor of the
basin in which Cambrian strata lie is occupied by a great sand-
stone bed. This is followed by a series of shales above the
middle of the formation, which series is in turn succeeded by
♦Geology of Wisconsin, vol. IV, 1882, p. 194.
tGeology of Wisconsin, vol. II. 1877, P- 537-
272 The American Geologist, May, i8»8
another sandstone reaching to the base of the Mendota* (St.
Lawrence). The average relative thickness is estimated to be :
Lowest sandstone, 300 feet.
Middle shales (Dresbach), 100 feet.
Upper sandstone (Franconia), 150 feet.
A similar succession is indicated in Minnesota by such
evidence as the boring of deep wells affords. The series of
shales and upper sandstones are well exposed and present
sufficient distinctness to allow subdivision. The lowest repre-
sentative of the Cambrian strata in the Northwest, the lowest
formation of the Basal Sandstone series, attaining a great
depth on the floor of the Pre-Cambrian basin, is not exposed
at any point within the St. Croix Dalles area. Therefore the
fauna of these strata seen at Taylor's Falls and vicinity does
not represent the earliest faunal characters of the Cambrian
as it is developed in Wisconsin and Minnesota. The lowest
sandstone member doubtless carries a fauna as characteristic
as other divisions of the formation. What variation there may
be is not yet known.
The Franconia sandstone includes the third trilobite bed
of Owen. Several species described by Hall also clearly be-
long to this formation. The following species are reported
from Franconia, Minn.:
Agraulus {ArioneUus)bipunctatus Shiimard.
Crepicephalus [^Conocephalites] diadernatiis Hall.
DiceUocephahis misa Hall.
Hypsehconus franioniensis^ n. sp.
Other localities have added:
Ai^nosfusjosepha Hall.
Chariocephahis whitficidi Hall.
Crcpicrphahts miftiscensis Owen.
Diccllocephalus misa Hall.
Lone hoc cphalus haniuius Owen.
Z. wisconsensis Owen.
Pfyc/iaspis {DiceUocephahis) granulosa Owen.
P. (Dicellocephalus) miniscensis Owen.
Ptychoparia {Conocephalites) anatina Hall.
P, {(\ynocepha/i/es) nasufus Hall.
P. " patersoni Hall.
P. " perseus^?\\.
P. " shumardi HaW.
♦Geology of Wisconsin, vol. I, p. 121, 1883.
Geology of the St, Croix Dalles, — Berkey. 273
The principal localities are Franconia, Chippewa river,
Trempeleau,Minneiska, Black river, Marine Mills and Kicka-
poo river.
Fossils from this formation are poorly preserved. No part
of the shell is present and this sandstone is so friable as to
render the casts which alone represent the fauna extremely
fragile materials to work upon.
The Dresbach sandstones and shales are in great contrast
to the Franconia sandstone. Whereas in the Franconia for-
mation there are no shells and few casts ; on the contrary, in
the Dresbach shales immediately below they are so abundant
that a single hand specimen from a favorable point contains
hundreds of fragments of brachiopod shells. The range of
species is limited and the considerable addition which is made
in this paper as to variety of forms has not indicated a very
extended geographic distribution. These new forms are de-
scribed in a later chapter. Fossils reported from the Dres-
bach at Taylor's Falls and St. Croix Falls are:
Lingula ampla Owen.
. L, antiqua Hall.
{LinguiePis pinniformis Owen.)* Lingulepis acuminata Con.
Obolella polita Hall.
In addition to these the following were found recently
by me:
Hyalithes primordialis Hall.
Hypseloconus {Metoptoma) recurvus (Whitfield).
Agraulus convexus Whitfield.
Ptychoparia calymenoides Whitfield.
and a considerable number of new species which are de-
scribed in a following chapter. Other localities have re-
ported the following species from this horizon:
Crepicephaliis {Conocephalites) eos Hall.
Dicelhcephalus iowensis Owen.
Ptychoparia ^^Conocephalites) minor Shumard.
Hyalithes primordialis Hall.
Platyceras primordialis Hall. {Sccpvogyra probably.)
In addition to these foregoing species noted with compara-
tive certainty under their respective formations, there are a
*A recent article by C. D. Walcott makes Lingulepis pinniformis
Owen a synonym for Lingulepis acuminata Con.
274 The American Geologist May, i*ft
number whose horizons are so uncertain or so poorly defined
that any attempt to limit them to a definite formation is
largely a matter of conjecture. They are therefore grouped
in a list by themselves with this explanation, that they prob-
ably represent a vertical range from the Jordan sandstone of
the Magnesian series down to the lowest beds of the Basal
Sandstone series.
Palaophycus plumosum Whitfield.
Aglaspis etoni Whitfield.
Agraulus luoosteri Whitfield.
A. {Arionellus) convexus Whitfield.
Crepicephalus gibbsi Whitfield.
C. onustus Whitfield.
Ellipsocephalus curtus Whitfield.
Dicellocephalus lodensis Whitfield?
D. latifrons Shumard.
Ptychaspis batabuensis Winchell.
P. [Conocephalites] quadrata Whitfield.
P. minuta Whitfield.
P. striata Whitfield.
Arenicolites woodi Whitfield.
Leptctna barabuensis Whitfield.
Triplesia Pritnordialis Whitfield.
Ophileta {Straparollus) primordialis Winchell.
Piettrotomaria advena Winchell.
Scolithus linearis Hall.
The remarkable group of fossils from Eikie's quarry, near
Baraboo, Wisconsin, bears such a striking resemblance to the
new forms from the Dresbach at Taylor's Falls that it seems
most proper to enumerate them here. Notwithstanding the
difficulties of stratigraphy at Baraboo and the inclination of
the Wisconsin geologists to place them much higher in the
series of formations, it is at least clear that the two faunas are
in all essential respects similar. The Baraboo fossils are:
Ltptcpna {Orthis) barabuensis Winchell.
Euomphalus strongi Whitfield.
Tryblidium {Metoptoma) barabuensis (Whitfield).
T. {Metoptoma) simi/is Whitfield.
T, {Metoptoma) retrorsa Whitfield.
Hypseloconus {Metoptoma) reeuri'us (Whitfield).
Sccevogyra eleifata Whitfield.
S, obiiqua Whitfield.
S, swezeyi Whittle Id.
Geology of the St. Croix Dalles. — Berkey. 275
Dicellocephalus bar&buensis Whitfield.
D. etoHi Whiifield.
Illdttunis convexus Whiitield.
Chapter II. Additions to the Fauna.
The greater part of the sedimentary strata in this area is
made up of porous friable sandstones and shales unfavorable
for the preservation of organic remains. Calcareo-j.s portions"
of the lower Dresbach shales are, however, favorable for pres-
ervation and in them are crowded great numbers of Lingu-
lepis pinniforinis and related forms. Certain pcrtions of the
green-sand horizon also are packed with the broken fragments
of shells. Although fragments are so abundant it is almost
impossible to obtain specimens from the green-sand bed suffi-
ciently well preserved to be identified. Portions of the finer
grained sandstones still preserve the imprints of numerous
forms, although in most cases no trace of the original shell
remains. These occurrences are always limited in extent, and .
consequently in many outcrops they are not to be found at all.
One of the most promising localities for fossils is Lawrence
creek gorge at Franconia, from which several good fossilifer-
ous slabs were taken. The marginal conglomerates have
proved most fruitful, and recently a fauna has been discovered
in these conglomerates which is unique. Several new species
and a few rare types are included in it. The general character
of the fauna is essentially that represented in the Baraboo
fossils described by Whitfield in Geology of Wisconsin (loc.
cit.). Over a hundred specimens have been obtained and
the range of variability which they exhibit throws some hgnt
upon classification of the early forms of gastropods. The
gastropods are almost wholly of the conical type with oval
aperture. They thus belong to Tryblidium and related
genera.
lumber of spe-
ong to the dis-
pecies of cont-
■e placed in the
lecies of all re-
in outline. Ii>
descriptions of
2/6 The Americofi Geologist May, law
these primitive types and the detailed study of considerable
material the following statements may be conceded to have
the support of all facts at hand.
Nothing is known as to the real nature or internal struct-
ure of the earliest forms classed as gastropods, and in the
absence of biologic evidence the only rational basis of classifi-
cation is that of variation in form.
Results based upon material of exceptional value for such
investigation, and a tentative recast of the related forms de-
scribed from the Cambrian, lead to the conclusion :
1st, that the simple symmetrical cone was probably the
earliest form of gastropod.
2nd, that this form is represented by a group of fossils
whose specific variation consisted in:
a. Variation in highl.
b. Variation of aperture in shape between the circle and symmetri-
cal ellipse.
c. Variation in striation, growth lines and radial striae being at
most only specific characters and subject to obliteration in the process
of fossilization.
d. Variation in thickness of shell.
ft
Following the line suggested by a study of the material
in hand there seems to be two steps in variation exhibited:
1st, a tendency to acuminate aperture followed by or ac-
companied by excentricity of apex.
2nd, a tendency to a more irregular aperture usually
more or less triangular or notched followed by or accompan-
ied by more or less excentricity of apex.
The first of these lines of variation gives rise to two di-
vergent branches: ist, those anteriorly (acuminately) inclined;
2nd, those posteriorly (obtusely) inclined or recurved. The
first is the Tryblidium type. The second is typified in a new
genus TJypselocoftus,
Specific distinctions are chiefly questions of
a. Size.
b. Comparative excentricity of apex.
c. Apical angle.
d. Striations of all kinds.
e. Variation ffom typical aperture. ,
f. Comparative curvature of the sides.
Geology of the St. Croix Dalles. — Berkey. 277
These two lines of variation are valid morphologic grounds
for generic distinction and division. They exhibit an un-
broken series of forms leading to independent but perhaps
closely related genera. Regarding internal muscle scars it
is evident that a statement recently made in a work upon this
subject by Mr. Ulrich needs revision. His statement is es-
sentially as follows:* An examination of all forms on which
muscle scars are known supports this biologic or structural
law that:
1st, all forms in wliich the muscle scars are interrupted
are anteriorly (acuminately) excentric.
2nd, all forms in which the muscle attachment is continu-
ous are posteriorly (obtusely) excentric, i. e., the apex in-,
clines toward the larger rounded margin of the aperture.
Notwithstanding this general statement by Mr. Ulrich, I
must insist that it does not apply to the forms to be described.
Paired muscle scars have been detected in both lines of varia-
tion. A few of the obtusely inclined forms show the marks
so well and are at the same time such typical specimens of
their own group that no rule of such sweeping generalization
could be formulated, especially since most primitive types
show nothing for or against such conclusions.
Faunal Relatiomhips, — There have been no less than nine
diflferent generic names proposed for the simple cone-like,
shells which occur fossil in Palaeozoic rocks. Among these
most all possess characteristics either of form or muscle at-
tachment sufficiently constant to hold an independent place
in classification. A few of them, however, seem to be based
upon characters of too questionable value for generic distinc-
tions, notwithstanding their apparent value in distinguishing
species or varieties or individuals. Such a character, for ex-
ample, is that of surface marking. With the large number
of specimens in hand it seems to be shown in these forms, as
has been long known in many others, that fine or coarse stria-
tion either radially or concentrically or even strong plication
are characters of comparatively little taxonomic importance.
Among the obstacles to a correct adjustment is the magni-
fied apparent discrepancies of type arising from great difFer-
*Geol. and Nat. Hist. Surv. of Minn., Final Rep., vol. Ill, part II.
1897, p. 828.
278 The Antefican Geologist. May, l88^
ences in size and state of preservation, e. g., between certain
species referred to Tryblidium and some of thfe forms referred
by authors to StenotJieca it is difficult to describe, a satisfac-
tory difference beyond the fact that one is twenty times the
size of the other, although a glance would seem to be suffi-
cient to separate them.
The tendency among American paleontologists until re-
cently was to place many unlike forms in the genus Mctop-
toma^ Phillips, 1836. Since 1872, however, as new forms
have been studied, distinctions have been made which allow of
a considerably more complete subdivision.
The Metoptoma type is truncated under the apex and has
a horse-shoe shaped muscle scar. These two points together
serve to distinguish the genus. No materials in the Taylor's
Falls collection belong to this genus.
Lcpetopsis, Whitfield, 1882, is from later formations and
is sufficiently well distinguished from all of the more primitive
types by its dextrally coiled nucleus.
SccfuUa, Billings, 1872, includes patelliform shells with cir-
cular or oval aperture and subcentral apex. Muscle attach-
ments form a complete circle so far as known.
Stefiothica, (Salter), Hicks, 1872, and PaltBacnujeay Hall
and Whitfield, 1873, may be divisions worthy of generic dis-
tinction, but in the present condition of our knowledge they
can scarcely be given more than sub-generic rank with any as-
surance, smce surface ornamentation alone cannot be very gen-
erally accepted as a generic character.
CoHchopiltis, Walcott, 1876, is a lobed form and of so
irrej^ular outline and altogether of so uncertain affinities that
it need not claim serious attention in a study of the types in
hand.
AtrhindctlLu Ulrich. 1807. presents some perplexities. In
so far as a continiunis muscle attachment coupled with the
outline of Tryblidium is substantiated by actual specimens
there seems to be a place for the genus. But since a major-
ity of tlie species referred by I'lrich* to this genus do not
exhibit well marked muscle attachn^ent of any kind and in
at!<iition contv^^nn close! v in oittline eitV.er to TrxbUdiHm or to
Tico! ai:v] Nat Hist. Siirv. of Mir.^\. Firt.i! Rep., vol III, part 11.
Geology of the St, Croix Dalles. — Berkey. 279
Scenella, there would seem to be reason for setting the term
aside for the present in doubt.
Tryblidium, Lindstrom, 1880, is a well defined genus,
which as shown by known materials comprises patelliform
shells with oval or anteriorly acuminate aperture and with
muscle scars forming a circle of six (or more) pairs. The
apex of the shell is directed anteriorly, i. e., toward the acum-
inate margin of the aperture.
Helcionopsis, Ulrich, 1897, is based upon but one charac-
ter, i. e., fine radiating striae upon the surface of the shell. It
is clearly a Tryblidium. The distinction is certainly of no
more than specific value.
Another group of which a large number of specimens have
been collected during work upon the "Geology of the St.
Croix Dalles" comprises conical shells with the apex bent
backward. The curve from apex to posterior (broader) mar-
gin is therefore concave instead of convex as in Tryblidium,
Muscle scars are similar to Tryblidium as indicated on the
casts. This group is in fact united with Tryblidium through T.
rectilaterale , n. sp., but is separated into a new genus because
of the direction of development which is toward Eccyliompha-
lus instead of toward Patella and on account of the radically
different form which at once develops in this line. T rec-
tilaterale again when compared with Hypseloconus ap-
proaches H, cylindricus, n. sp., most closely which is only
slightly acuminate and excentric and its musculature is un-
known. H. cylindricus differs from Hyolithes chiefly in its
direct non-oblique and oval aperture T, rectilatcrale has
the oblique aperture but. not the triangular cross section of
Hyolithes while Hypseloconus recuri'us, var. triangidatus^ has
a suggestion of the triangular outline but not the typical
aperture. There seems to be indicated altogether a primi-
tive relationship between the Patellidce, Euompltalidce, and
perhaps also a more remote relationship to the Pteropoda.
Description of Species.
gastropoda.
Genus Tryblidium, Lindstrom, 1880.
In conformity with the facts just noted bearing upon specific varia-
bility, it is deemed best to include a greater range of forms within this
genus than has been at times customary.
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Geology of the St. Croix Dalles, — Berkey. 281
Tryblidium barabuensis (Whitfield.)
Metoptoma barabuensis Whitfield. Ann. Rept. Wis. Geol. Survey for
1877, p. 60, 1878.
Metoptoma barabuensis V^\i\\.^^\A, Geol. Wis., vol. iv, p. 195. 1882.
Metoptoma barabuensis Sardeson. Minn. Acad. Nat, Sciences, vol.
IV, part I, p. 97, 1896.
Plate XX, Fitfs. 18 and 19.
It was first thought that the form described as T, convexum above
was identical with Metoptoma barabuensis of Whitfield, but the fol-
lowing points of difference were considered of too much importance for
such identification:
The apical angle of T. barabuensis is 70° : the apex also falls outside
of the anterior margin, and the posterior slope is quite convex, while
the anterior slope is slightly concave. A specimen collected and identi-
fied by Dr. Sardeson from Osceola conforms closely to this type, dif-
fering chiefly from Whitfield's specimen in the less broadly oval outline
of the aperture and the rather strongly developed growth plications.
Formation and locality: The Jordan sandstone, Osceola, Wisconsin.
Tryblidium extensum, n. sp.
Plate XX. Figs. 16 and 17.
Conical shell, inclined far forward so as to project considerably be-
yond the anterior margin; greatest hight of shell at a point immediately •
over the anterior margin, equal to 10 mm.; aperture is broadly oval,
slightly acuminate anteriorly; posterior slope uniformly more convex
than T, barabuensis ; anterior slope strongly concave; surface closely
concentrically striated; length 20 mm.; apical angle about 40°; distance
from the posterior margin to apex 26 mm.
This specimen is defective, but is sufficiently complete to allow res-
toration of all missing parts. It forms an important step in the mor-
phologic series.
Formation and locality: Dresbach. Found at Taylor's Falls in the
conglomerate.
This species is similar in general form to T. exsertum Sardeson
[Stenotheca exserta Llrich) from the Trenton, although it is very dif-
ferently marked and less acute at the apex.
Tryblidium corpulentum, n. sp.
Plato XX, Fitfs. 21 and 22.
Shell small, conical; apex obtuse and inclined beyond the anterior
margin; posterior slope very convex; anterior slope concave; aperture
broadly oval, nearly circular, surface smooth. The convexity of the
sides gives this form a decidedly plump appearance. The relative width
is much greater than in any. of the closely related species. It resembles
some described species of Stenot/ura, but the gradation from this species
to the next one, which is clearly of the Tryb/iifium type, is so complete
in the specimens at hand that I have no hesitation about its position.
Highest part of shell a little forward of the middle, 6 mm.; hight of
/ ' " /'• • ' ' i '/•<.. J'.**- zrf.z^ t:L I. p. J9)»
' / / ' ,/••'' .% ' '. •'.•T^.. 2- r«> shr-ws this lateral
^ ^ /'.,.»-... y/'^/^^'/'it ^T.'i from a later forma-
1 ,. J M.l . ♦ mI |(» • Mill H^ liiivr t)fcn secured which arc of the
I I , n|M .Mini l»v I/' /''/'A'/z^Mz-v/z/T'ir Whitfield.* A study 0/
I ,,,, III, III. » nil iliM'^t «»Mi»r / 'm 7» //«//;/w type ami others 'u:-
I ,,1. »lm On \ lMl«>nn tt> rt now iffcnuj^. The \-amt!:'n ^^
, ,,,, \ I, ^^^^ \^ \A io ^ \<\\ \\\^cvcwx line cvi deve:':;--?"*
V \ . ' » o,^v ^^-'.^^ <^^^»c «':r t^:c ^t" r :: '- -
-^
Geology of the St, Croix Dalles, — Berkey. 283
the aperture under a new generic name. The forms collected rep-
resenting this genus are so extremely variable among themselves and
even on diflFerent parts of the same individual that it has been found
inexpedient at this time to subdivide them very closely into species.
Accordingly the greater number of specimens are grouped together
under the specific name recurvus already in use as defined by Whit-
field. The particular individual or varietal form however which Whit-
field described and figured is not considered the best type of the
genus. It seems to be an extreme or abnormal individual. There-
fore one which is represented by several perfect casts was chosen in
its place, (see plate XIX, figs, i and 2). I am of the opinion that M,
retrosra Whitfield is essentially of the Tryblidium type and should
not be transferred to the new genus. The apex of this specimen
is defective and my experience with some of the peculiarities of these
types leads me to believe that the recurved character of the apex is
overdrawn in the reconstruction by Whitfield. It is believed that
Metoptoma alta Whitfield, M. venilia Billings. M. orythyia Billings,
and perhaps others should be transferred to this genus.
The shells of all specimens are quite thin. On the only specimen
preserving a part of the shell it measures from .25 mm. to .45 mm. in
thickness. On many others the original thickness is readily estimated
by the separation of the walls of the cast and the results indicated
in this way are very little greater than those given above. Variation
in size is as great as in any other particular. The largest fragment
indicates an aperture of more than 50 mm. through the longer axis.
A portion of the cavity once filled by one of these forms has been
estimated to require a shell over 100 mm. in length.
Several of these specimens have a well defined slightly depressed
area extending completely or almost completely round the cast usual-
ly about one^fourth to one-third the distance from the base to apex.
The persistence in occurrence and position of. this band strongly sup-
ports the view that it represents the position of muscle scars of/this
genus. On several casts there is a circle of slightly raised areas lying
in. this position on the cone. On only a few casts are these well pre-
served but in all such cases the marks are the same in form and po-
sition and number. It is therefore added as a character of the genus,
— that the muscle attachments form a circle of six pairs of scars con-
siderably above the aperture and parallel to it.
Description. Shell conical, high; apex smooth and more or less
curved or recurved toward or even beyond the broader margin of the
oval aperture; aperture entire and more or less acuminate anteriorly;
surface smooth or striated; muscle scars in six pairs forming a circle
parallel to the aperture and about one-third the distance from base to
apex.
284 Tlu American Geologist. May, i8»*
Hypseloconus recurvus (Whitfield), var. elong^atus, n. var.
yfetoptoma recunfa Whitfield. Ann. Rept. Wis. Geol. Survey for
1877, P- 61, 1878.
Metoptoma recun»a Whitfield. Geol. of Wis. vol. IV, p. ig6. 1882.
Plate XYII, PUr. I. PUt« XIX. Fi«s. 1 and 2. Plate XXI. Figs. 2. 14 aod 21.
Shell conical, very high, upper portion of shell curved very moder-
ately toward the broader posterior margin of the aperture; apex
>lightly posteriorly excentric, smooth and erect; aperture entire, plane,
and a very flat oval in outline, broader posteriorly- ; length 21 mm;
wiiit'.i It mm: highi of shell ^ mm; surface bears strong growth
plications or fine growth lines or is entirely smooth. Apical angle.
40*^ X 30' : apical excentricity 5 mm.
Formation and locality: Upper Dresbach. Tajlor's Falls con-
glomerate.
In addition to this particular form there are among these speci-
mens many individuals showing marked ditferences among themselves
but connected in each case by intermediate forms, and who>c exist-
ence makes further subdivision at this time inad\*isable. The more
prominent of these individuals are figured in plate XIX. Figures 5
and & represent a peculiarity of the anterior slope similar to that noted
Ny \\>.;tr.eM in 7*. •.V*^/v*/*.Vi^j n/r-rrsj. This peculiarity resolves
!tse!: hc^wever into a mere constriction of the aperture during its
'ater gTo\*".h and cannot be cor.s-.dered very imp«."»rtant- It shows
:^^■ust:^. :n aiiii-.r.on a niore acute aperture anteriorly ihan most of the
>;-<-c:rcr.>. T:::> :r.ii:v:d:'al is a'>o represented in p'ate XXI. fig. 12.
a F'.gs. ,x. 4. 7. J^ .21 ard j;.: are forms ir.terme^iiaie between the
:}pe a* rt presented :n r.jrs- 1 ar.d 2* ard that t:ir-red by Whitfield
iS .«.'. •.•.x-i.i . These are a'l necur^ed. ihe apex :s anterior to the
ctr:er. bet the pv >:cr:cr >\ ;H^ :s not reir'y >t% abr.orma!!y developed
;.> \\ '.:.:f:t\:"> >:xv-.tr. r\4:c XXI. f.g it. :s frcizi a photograph
~: . r.e c: :ht>e s7Kv:r.-er.s
h F-*:> ->~ *'- V rtrroer.; a <j'»ec-r:e': m:h apex much extend-
V'. T>t i:i-^--< i"-' :< •~';:ch -^v^^c ^on-^cv.: thar. rr-.-^t of the forms.
T'-^e rv^ic— r >' .x ^c^-": t> :"-c rc-'e h> \\'".:rt'c more closely.
F *:n .:5 i"i z^ :.T.i ^'yr r.c \? v ' r ite XX I represent two
'■jxc — v~> •• *• >-c A-:ir " >' :< :> ^^i*:-.::.- — icir-rj: a consfriction
.! ^ ^"^ \> ,'~v- '4. *5 <?-'"-*- •" '"v .'^v-^v''! z- -i a ^venniens in which
:"c ;..vx -^ ,:rv .. > — — t .\.~v":"c f.v- >::''"i-4r''i' ard the gcn-
i^L i: .:":.'v-c ."" :x '*■* »: .> .-£ :'t - : ""i-- r. :hit there is a
r -.-v-r.< - ?•' --: - ;."> : ---\--t >\ r-^:.-^'f~c-.'t>. biit these
... » _- . .- ^. . ^ . ~. -^ ^ ^ ^ > .. ._ ..^ ^ ..^^ ^^^ which ai-
-,--"■- -' . N . - V- • V ■ , - - V ■ c ■-,.-: -: hi> been fooud
,. ' .- . ' ^ ■ .* " V- :• -. s :- • . . ^ -. -: ~ -:>> wrrhtu this
Geology of the St, Croix Dalles, — Berkey, 285
gatus), group a^ var. erectus, b, var. attenuatus, c, var. triangulatus^ d,
var. marginatus.
Hypseloconus cornutiformis, n. sp.
Plate XIX, Figs. 11 and 12.
Form high and curved far beyond the posterior margin, forming
one quarter volution; surface smooth; curve regular; aperture a
flattened oval acuminate anteriorly; hight above base 30 mm; length
18 mm; width 12 mm; apical angle small; apical excentricity 7-10
mm. beyond the broad margin. The apex of the specimen is defec-
tive.
Formation and locality: Upper Dresbach, Taylor*s Falls.
Hypseloconus capuloides, n. sp.
Plate XIX. Figs. 19 and 20.
Shell small, high, strongly curved equal to one-third volution; surface
smooth; aperture entire and much flattened; highest part of shell im-
mediately above posterior margin, extremity curved slightly down-
ward. Hight 10 mm.; length 8 mm.; width 4^. mm.; apical angle
small; apical excentricity 2 mm. beyond margin.
Formation and locality: Upper Dresbach, Taylor's Falls.
Hypseloconus franconiensis, n. sp.
Plate XIX. Fiffs. 17 and 18. Plate XXI. Fig. 10.
Shell small, slender, uniformly coiled to one-half volution; apex
smooth, curved downward and slightly inward beyond the posterior
margin; aperture defective but apparently entire and oval; surface
smooth: hight above base 10 mm.; length of base 8 mm.; apex 5 mm.
beyond margin.
Formation and locality: The Franconia sandstone, Franconia, Minn.
This form might possibly be placed with the genus Eccyliomphalus .
But on account of the series with which it is associated it seems
preferable to describe it with them as a representative of one of the
extremes of variation in the genus.
Hypseloconus cylindricus, n. sp.
Plate XIX. F1k«. 9 nod 10.
Form very high, conical, approximating a circular outline of sec-
tion, but slightly compressed anteriorly; apex absent, but a slight in-
clination is easily observed; sides almost straight; surface strongly
growth marked even to extent of plications: apex subcentral to sub-
marginal. Reconstruction indicates these measurements; hight 25
mm.; lentJ^th 12 mm.; width 10 mm.; apical angle 20**. A smaller
specimen measures 21, 8 and 6 mm.
Formation and locality: Upper Dresbach, Taylor's Falls.
This and the following form might possibly be classed with See-
.^^ ^z ;;-:■.£.-=-
-zzi : z^ ^cTci'iz ce:-
' ' • ' "r •■' I i ..-r.-r^-j^ ^-,^ r»: j-,^^ 2T1C a hall to t\»o u-
''''"' '' M- ' av'»'»; th*r b'iCT "w-faur!: expanding rapido-
• • *« < i «« ■ « \ny : fiMv»':Tjjr aii indicauoii of the tmnipet lonn <^'^
' i\t / < ••* /. i»'w ]iTje* paraljel to the apertnre are regular.
1 1'» • '• '•'" »i tiiifnhrr of volutions, and aperture arc snfficient ti-
\ fi'M li \\ (tiiftt \\\%' Utiown "species.
( . iM.i»i..fi timl '\x\K.\\\\y\ The Dresbach at Taylor's Falls in the
I I > 1 1 tn • t 'I I •
I <
H, I'.p \ \ Mus. Kat. Hist., 1863, p. 136.
Geology of tfie St. Croix Dalles. — Berkey. 287
Genus Euomphalus, Sowerby, 1812.
Euomphalus strong:! Whitfield, var. sinistrorsus, n. var.
Euomphalus strongi Whitfield. Ann. Rept. Wis. Geol. Survey for
1877, P- 66, 1878.
Euomphalus strongi V^\{\\&e\^. Geol. Wis., vol. IV, p. 200, 1882.
• Plato XX, Fiff. 23. Plate XXI, Fig. 9. .
The specimen identified as E. strongi presents the characters given
by Whitfield in most particulars. These differences however should
be noted. Number of volutions one and a half; cross section of body
sub-circular, slightly sub-angular at the outer side; inner side decided-
ly flattened and slightly indented by preceding whorl; coiled a little
out of the same plane indicating a tendency to the sinistral spire.
Formation and locality: Dresbach, Taylor's Falls, in the con-
glomerate. Originally described from Baraboo, Wisconsin, by
Whitfield.
Gen.? sp.?
Plata XX. FiK. 2U. Plate XXI, Fig. 15.
The specimen represented by these figures was the first one found
of the large number from the conglomerates at Taylor's Falls. The
fisrure is from, a fragment of a mould and is not complete enough to
warrant reconstruction and description. It appears to indicate a
tendency to spiral coiling of the dextral type, about one-half volution.
It is to be hoped that other and more perfect specimens may be found.
TRILOBITES.
Trilobites are found in the conglomerates at Taylor's Falls more
abundantly than any other fossils with the exception of. Obollela
polita. In this case also a greater distribution is noted. Many speci-
mens of a species of Dicellocephalus were found in the Franconia
sandstone in a horizon at least loo feet higher than the conglomerate
strata. All but two specimens are referred to the genus Agraulus
and are closely related as a group to A. convexus Whitfield, the
greater number of specimens clearly belonging to that species. One
of the other above-mentioned specimens is regarded as identical with
Ptychoparia (Conocephaliies) calynienoides Whitfield, while the othc*
is so clearly distinct from any form with which I am familiar that it
is described as the type of a new genus.
Genus Agraulus, Hawle and Corda, 1847.
The trilobites found in this conglomerate are very closely related
to A. convexus Whitf. Many specimens are no .doubt of the same
species while those showing a considerable difference have been as-
signed new specific names. A considerable range of variation is al-
lowed for Whitfield's species on the grounds suggested in a later
paragraph. The described differences are of necessity confined to
the head parts and their proportions since the other parts of the
animal are poorly preserved.
288 The American Geologist May, isss
In all of the forms here referred to Agraulus the eyes are far re-
moved from the glabella, and the facial suture extends from the eye
with a slight curve directly to the lateral margin cutting it at nearly
a right angle, and posteriorly it cuts the margin just within the genal
angle. The glabella is clearly defined but shows marked differences
in the several groups of specimens.
Agraulus convexus Whitfield.'
Arionellus [Agraulos) convexus Whitfield. Ann. Rept. Wis. Geol.
Survey for 1877, P* 57» '878.
Arionellus con^fexus Whitfield. Geol. of Wisconsin, vol. IV, p. 190,
1882.
Plate XX, Fiffs. 9, 10 and 11. Plate XXI, FiRe. 3 and 7.
Cephalic shield strongly convex; glabella strongly defined by the
dorsal furrows, somewhat narrower at anterior extremity and bound-
ed by almost a straight line which curves narrowly to the dorsal fur-
rows; three faint oblique lateral furrows on the glabella; occipital fur-
row deep above but disappearing at the dorsal furrows and again
continued faintly across the posterior portion of the fixed cheek; fixed
cheeks a little more than half as wide as the glabella, strongly arched
at the eyes: frontal limb deeply cut by a 'median groove which marks
oflf an anterior marginal rim, wider and more prominent in front
than at the lateral margins, forming a rounded and thickened projec-
tion extending at a considerable angle beyond the general convex
contour of the shield. Facial suture runs from the eyes anteriorly out-
ward so as to cut the lateral margin at almost a right angle and pos-
teriorly runs abruptly to the margin within the genal angle; eyes pos-
terior to middle of glabella; length of glabella 7 mm. without ring;
length of- shield 12 mm.; width of glabella anterior ^Y^ mm.; poster-
ior 6 mm.; width of cheek 3 mm.; frontal limb zVa nim. The pygid-
ium, fig. II, is supposed to belong to this species.
Formation and locality: Upper Dresbach, Taylor's Falls.
In addition to the form for which the above description was writ-
ten there are two others which are so similar in most points except
size that they are provisionally regarded as stages in the growth of
this species. One (A) is larger and the other (B) smaller than the
measurements given. The former is probably a senile individual and
the latter an immature form.
Variety A.
Plato XX. FiRs. 1 and 2. Plate XXI, Fig. 5.
Cephalic shield more flattened giving a broader aspect to the
head. Markedly less convex over the eyes. Occipital furrow imper-
fectly marked; glabella smooth; median groove very faintly traced
and the marginal rim follows the general convex contour of the rest
of the shield.
Variety B.
Plate XX. Figs. 5 and 6.
Form rather small. The cephalic shield is semicircular to lunate,
strongly convex, greater width than length; glabella anteriorly con-
Geology of the St. Croix Dalles. — Berkey. 289
vergent with broadly and uniformly rounded termination, strongly
outlined; three pairs of lateral furrows inclining forward, anterior pair
very faint, lateral pair prominent; occipital ring very prominent, the
neck furrow passing laterally across fixed cheeks; fixed cheeks large,
convex, continued as a margin to the glabella sloping into a deep
transverse furrow separating it from a narrow cord-like marginal rim.
Length of glabella 5 mm.; inner margin less than 2 mm.; marginal
rim I mm.
Agraulus hemisphericus, n. sp.
riato XX, Fi«s. 14 and 15.
Cephalic shield strongly and uniformly convex, in general outline
resembling liicenus. Glabella very faintly outlined, elongate with
slowly converging sides to a point two-thirds the distance to anter-
ior margin where it is terminated by a faint groove parallel to the
margin; surface of glabella smooth; occipital ring outlined indistinct-
ly and continued across the fixed cheeks similarly; fixed cheeks large
and conforming to the general convexity; frontal limb without groove
and continues the curve of the glabella; eyes far removed a little pos-
terior to the middle of the glabella from which the facial sutures pass
anteriorly outward cutting the margin at right angles and posteriorly
with a short lateral curve cutting the margin evidently within the genal
angle. Length of head 15 mm.; width 21 mm.; length of glabella 10
mm. exclusive of occipital ring; anterior width 7 mm.; posterior
width 9 mm.
Formation and locality: Upper Dresbach, Taylor's Falls.
Ptychoparia calymenoides (Whitfield).
Conocephalites calymenoides Whitfield. Ann. Rept. Wis. Geo!. Sur-
vey for 1877, p. 52, 1878.
Cottocephalites calymettoides Whitfield. Geol. Wis. vol. IV, p. 179,
1882.
Plate XX. Fiffs. \\ and 4. Plate XXI. FIr. 4.
A specimen agreeing accurately with that described by Whitfield
has been obtained. Unfortunately the head is not preserved, and the
same difficulty as Whitfield encountered is in the way of more accurate
description.
Formation and locality: Dresbach, Taylor's Falls.
Genus Cheilocephalus, new genus.
Etymoloffv: cheiloa, a lip or rim, and cephale, head.
Description. Cephalic shield semicircular, strongly convex, about
equal to one-fourth part of a spheroid; anterior (frontal limb) formed
by a narrow ring projecting at a right angle beyond the general sur-
face of the shield; glabella broad, convex, anteriorly slightly con-
vergent and reaching to the narrow marginal rim, surface nearly
smooth, with 2 pairs of scarcely perceptible furrows, marginal grooves
not strongly marked; faint occipital ring (neck ring) but more strong-
ly marked on the cheeks; fixed cheeks broad and conforming to the
general spherical outline; the posterior margin developed into a spine
290 The American Geologist. May, i898
like projection a little removed from the glabella; eyes a little anter-
ior to the middle and remote from the glabella; facial sutures extend
from the eyes forward almost parallel to the sides of the glabella and
backward with a double curve to the genal angle.
Movable cheeks unknown as are also the other parts of the form.
The description is based on one specimen excellently preserved.
Cheilocephalus st. croixensis, n. sp.
Plate XVII, Fi«. 1. Plate XX. Figs. 7 and 8. Plate XXI, Fig. 19.
Size of head, width 25 mm.; length 16 mm.; marginal rim, width,
ij^ to 2 mm.; glabella length 15 mm.; width anterior 9 mm.; poster-
ior 13 mm.
Formation and locality: Upper Dresbach, Taylor's Falls.
Genus Dicellocephalus, Owen, 1862.
A number of specimens whose affinities were doubtfully referred to
either Ptychoparia or Dice Hoc epalus were upon a comparison of the
detailed descriptions of older species finally grouped und^r a single
species D. tnisa Hall,* 1863.
In a paragraph following the original description of this species an
explanation is made by the author which throws a good deal of light
upon these forms and accounts to a certain extent for the rather more
than usual difficulty in identification. He says: "In species like this
one, it is not easy to point out the characters which separate them
from such forms as D. spiniger or D. pepinensis and we have the fea-
tures of glabella intermediate between the more characteristic forms
of Conocephalites {Ptychoparia) and Dicellocephalus, In this
one the glabella is more conical and the posterior glabellar furrows
scarcely united across the summit."
"The pygidium which occurs in several specimens associated with
the glabella, has the prominent axis and broad lateral lobes with wide
margin which are characteristic of Dicellocephalus and I am there-
fore induced to place the species under that genus."
Diceilocephalus misa Hall.
Dikelocephalus misa Hall. i6th Rep. N. Y. Mus. Nat. Hist., 1863, p. 14.^.
Plat<^ XX. Figs. 12 and \\\,
"Glabella prominent, somewhat conical, truncate at the apex.
length about equal to width at base, which is more than one-third
greater than the width in front. Three pairs of furrows are visible;
the posterior ones oblique and sometimes slightly marked across the
middle, leaving the posterior lobes deeply separated and directed for-
ward at the extremities. Median lobes and furrows directed a little
forward; anterior furrows faintly impressed, leaving a very narrow
anterior lobe; occipital furrow well defined, straight in the middle,
*i6th Rep. N. Y. Mus. Nat. Hist., 1863, p. 144.
Geology of the St, Croix DalUs, — Berkey 291
and curving a little upward at the sides; occipital ring wider in the
middle curving forward towards the extremities."
"Facial suture directed slightly inwards froni the anterior margin,
and thence curving gently outwards, it follows the line of the palpe-
bral lobe nearly to the occipital furrow, when it turns abruptly out-
wards. Dorsal furrows rather wide and deep, continuing rather less
distinctly round the front."
"Fixed cheeks narrow, expanding in the direction of the eye, and
separated from the palpebral lobe by a long distinct sigmoid groove:
posterior limb narrow, its extent unknown. Frontal limb of mod-
erate width, separated from the glabella by a narrow groove, marked
along the middle by a broad shallow transverse furrow, which is
stronger at the sides and sometimes nearly obsolete in the middle:
anterior margin flattened, and a little produced in the middle."
Differences are chiefly in points relating to the frontal limb: The
smaller specimens differ only in having a narrower frontal limb than
those which are of twice the size. While those few specimens which
are very large have the frontal limb anterior to the groove very much
produced into a broad and promment shovel-like projection, whicii
adds much to the differences in comparative length of head in dif-
ferent specimens. The specimens vary in size from a length of 5
mm. to a length of 25 mm. for the head of the largest one found.
On account of this seemingly constant variation with the size
of the specimens, it has been considered most probable, in the ab-
sence of other marked differences that all belong to the same species
and that differences in size with accompanying development noted
above indicate the comparative maturity of different individuals.
Formation and locality: Franconia sandstone, Francon^a, Minn.
Chapter III. Summary and Correlation .
The vertical range of some of these species is shown to
be much grcctter than before supposed.
Lingnlepis pimiiformis Owen, is most abundant near the
base of the formation in the calcareous layers of the shales,
l)ut specimens are also found in the Taylor's Falls conglom-
erate indicating a vertical range of more than 125 feet. Above
the Dresbach no specimens of this species have been identi-
fied in this area.
Tryblidium barabtietisis (Whitfield), is identified from
the Jordan sandstone while the related forms T. convexum,
n. sp., and T. cxtctmim, n. sp., are from the marginal con-
glomerates of the Dresbach. Therefore the range exhibited
by these similar species is about 200 feet.
292 The American Geologist. May. i89h
The species of Agraulus show narrow range, as do also
those of Dicellocephalus, each being found in a single horizon.
The value of this fauna lies
1st. In its bearing upon the question of the position of these rocks
in the geologic scale.
2nd. In the addition that it has made possible to the paleontology
of the primitive Gastropoda.
3rd. In the morphologic series that the different species present.
4th. In the aid it has given to minor stratigraphic subdivision of
tliese formations.
5th. In the data furnished for use in correlation.
The general aspect of this fauna is identical or at least
very similar to the Baraboo fauna described by Whitfield,
which he referred tentatively to the Oneota of the Magnesian
series. Evidently the strata from which it was taken must
belong to a lower horizon at or above the middle of the Basal
Sandstone series in accord with the possibilities of structure
pointed out by Irving, for no such excessive vertical range as
this is found in any locality where the succession of formations
is clear. But the Taylor's Falls fauna does not strengthen the
claim to strata of Middle Cambrian age in Minnesota. The
occurrences of species of EuompJialiis, Tryblidium, Agraulus,
Lingulepis, Obolella, Hyalithes, etc., all together, although
combining to a certain degree characters of both the Middle
and Upper Cambrian, do not as a whole present a primitive
faunal aspect. So that whatever may, after more careful ex-
ploitation, prove true of those strata represented by the great
lower sandstone member, it is at least probable that the
strata represented by the Dresbach shales and all above it
should be regarded as Upper Cambrian.
EXPLANATION OF PLATES.
Plate XVTI.
Figures about natural size.
Fig. I. Cheilocephalus s/. croixntsiSy n. sp., (type of genus). P. 2go.
Fig. 2. HypselocoHus recurvus (^\\\\.i.)^ var. e/onj^atus, (type of i?e-
nus). P. 284.
Plate XVIII.
Geological map of the St. Croix Dalles. The map is intended to lo-
cate the outcrops of the different rocks in more detail and with greater
accuracy in the vicinity of the village of Taylor's Falls than is possible
on the map of the whole district. The map covers four square miles.
Geology of the St. Croix Dalles, — Berkey. 293
Plate XIX.
Figures all natural size.
Figs. 1-2. Hypseloconus {Metoptoma) recurvus (Whitf.), var. elon^a-
tuSf (elevation and aperture). P. 284.
Figs. 3-8. Hypseloconus recurvus (Whitf.) P. 284.
Figs. 9-10. Hypseloconus cylindricus, n. sp. P. 285.
Figs. 1 1- 1 2. Hypseloconus cornutiformis, n. sp. P. 285.
P'igs. 13-16. Hypseloconus recurvus (Whiti.) P. 284. ,
Figs. 17- 18. Hypseloconus franconiensis, n. sp. P. 285.
Figs. iQ-20. Hypseloconus capuloides, n. sp. P. 285.
iMgs. 21-24. Hypseloconus recurvus (Whitf.) P. 284.
Figs. 25-26. Hypseloconus stabilis, n. sp. P. 286.
Figs. 27-30. Hypseloconus recurvus (Whitf.) P. 284.
Fig. 31. Outline of aperture of the largest fragment restored.
In each case the figure representing the elevation of a specimen is
followed by a figure representing the outline of the aperture of the same
individual.
Plate XX.
Figures all natural size.
Fig. I. Agrdulus {Arionellus) convexus Whitf., (senile individual).
P. 288.
Fig. 2. Side view of the same specimen showing diagrammatic out-
line. P. 288.
Pig. 3. Ptychoparia {Conocepkalites) calymenoides Whitfield. P. 289.
Fig. 4. Side view of same specimen.
Figs. 5 and 6. Agrauhts convexus Whitfield, (small specimen). P.
288.
Figs. 7 and 8. Cheilocephalus st. croixensis, n. sp. P. 290.
Fig. 9. Agraulus convexus Whitfield, (mature stage). P. 288.
Fig. 10. Side view of A. convexus^ (diagram of head). P. 288.
Fig. II. Pygidium of A. convexus probably. P. 288.
Figs. 12 and 13. Dicellocephalus misa Hall. P, 290.
Figs. 14 and 15. Agraulus hemisphertcus^n. s\i. P. 289.
Figs. 16 and 17. Tryblidium extensum, n. sp., (elevation and aper-
ture). P. 281.
Figs. 18 and 19. Tryblidium {Metoptoma) barabuensis (Whitf.) P.
281.
Fig. 20. Fragment of a partially coiled form of unknown position.
P. 287.
Figs. 21 and 22. Tryblidium corpulentum, n. sp. P. 281.
Fig. 23. Euotnphalits strongi^\\\xi.y\2cc, sinistrorsus. P. 287.
Figs. 24 and 25. Tryblidium convexum, n. sp. P. 280.
Fig. 26. SccEvogyra minnesotensis^ n. sp. P. 286.
Figs. 27 and 28. Tryblidium aduncum, n. sp. P. 282.
Figs. 29 and 30. Tryblidium rectilaterale, n. sp. P. 280.
294 The American Geologist, May, 1888
Plate XXI.
Fig. I. Lin^uiepis ptnnifarmis Ow^n.
LinguUpis acuminata Con. (Walcott).
Fig. 2. Hypseloconus {M.) recurvus (Whitf.), var. elongatits. P. 284.
Fig. 3. Agraulus convexus Whitf. P. 286. •
Fig. 4. Ptyckoparia calymenoides (Whitf.), (and head of A. convexus).
P. 28>
Fig. 5. ^^ATJtw/wi-o^/Jtfifjrj^y Whitf., (senile individual). P. 288.
Fig, 6. Hypseloconu%stabiliSy n. sp. P. 286.
Fig. 7. Agraulus convexus V^\\\\i.,{?i\^Xii%Q^VLt\, P. 288.
Fig. 8. //yPse/oconus recurvus iWhiti.), {smsiW). P. 284.
Fig. 9. Euomphalus strongi (^h\iL), w2iT. sinistrorsus. P. 287.
Fig. 10. Hypseloconus franconiensis, n. sp. P. 285.
Figs. 11-14. Hypseloconus recurvus (Whitf.), (three different forms).
P. 284.
Fig. 15. Fragment of a partially coiled form of undetermined affin-
ities. P. 287.
Fig. 16. Hypseloconus recurvus (Whitf.), P. 284.
Fig. 17. Tryblidium reciilaterale, n. sp. P. 280.
Fig. 18. Tryblidium convexum, n. sp. P. 280.
Fig. 19. Cheilocephalus St, croixensis, n. sp, P. 290.
Fig. 20. Slabs showing several casts of Hypseloconus recurirus. P.
284.
Fig. 21. Hypseloconus n?r«rz/«5 (Whitf.), var. elongatvs {typt). P.
284.
[Karopean anrl Amarican Glacial Gooloj^ Comparod, IV.]
THE PARALLEL ROADS OF GLEN ROY.
By Wabren Upham, St. Paul, MIdd.
In the western part of the Lochaber district of the central
Scottish Highlands, from nine to twenty miles northeast of
their highest mountain, Ben Neviss (4,406 feet), is Glen Roy,
in which the river Rov flows southwest to the river and Glen
Spean, tributary to the southern end of loch Lochy and thence
by the river Lochy to the sea in loch Linnhe at Banavie and
Fort William. These glens, with Glen Glaster (Glas Dhoire),
opening into Glen Roy from the east, Glen Collarig, which is
a lower affluent of the Roy from the west, and the upper part
o'f Glen Gloy. lying between Glen Roy and- loch Lochy, to
wiiich it is independently tributary, bear, on their inclosing
hill and mountain slopes three parallel horizont<il shore lines.
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The Parallel Roads of Glen Roy, — Upham, 295
(excepting that Glen Gloy and Glen'Spean have each only
one), which were the chief geological attraction and object of
pilgrimage for me in the British Isles.
Traditionally called roads of the mythical hero Fingal and
his hunting parties, these mysterious, delicately traced, level
lines far up the valley sides were long ago examined by Mac-
culloch, Dick Lauder, Milne-Home, and others, who ex-
plained them as shores of lakes once held in these narrow
mountain glens by barriers of detrital matter which afterward
were washed away. On the other hand, Chambers, Darwin,
Nicol, and others, from their examination, thought them to
be marine shore lines.
Agassiz, in 1840, visiting the district with Dean Buckland,
supplied the kej of the true interpretation of these shores in
the suggestion that lakes were held at the levels of the Parallel
Roads because the lower parts of the glens were obstructed
by glaciers. This view has been elaborated by Jamieson,
Prestwich, James Geikie, and others, ascribing these lakes to
local glaciers of the moimtain valleys, as in the case of the
Merjelen See on the east side of the Great Aletsch glacier in
the Alps. To my mind, however, this seems an inadequate
expression, far less acceptable than the latest discussion and
explanation given by Jamieson in 1892, in which the Lochaber
glacial lakes are referred to- the barrier of the waning and
southwestwardly receding remnant of the general Scottish
ice-sheet.*
The glacial lakes Roy and Gloy (as I may name them for
the present description) are the earliest recognized examples
of their class, which comprises many anciently ice-dammpd
lakes now known and partially mapped in the great valleys
and basins of Scandinavia east of its mountainous watershed
but west of the ice-shed during the Glacial period. In Amer-
ica, on a much grander scale, we have the glacial lakes Agas-
siz, Saskatchewan, Souris, and Minnesota, whose drainage
was turned by the waning ice-sheet into the upper Mississippi
river; and the complexly interrelated glacial lakes Duluth,
Chicago, Saginaw, Maumce, Whittlesey, Warren, Algonquin,
♦Quart. Jour. Geol. Soc, XLVIII, 5-28. This paper has many biblio-
graphic references to the extensive literature of the Parallel Roads, for
which also consult William Jolly, in Nature, XXII, 68-70, May 20, 1880.
296 The American Geologist May, i898
Lundy, Newberry, Iroquois, Hudson-Champlain, and St.
Lawrence, in the compound hydrographic basin of the present
great lakes tributary to the river St. Lawrence. For the
United States and Canada, Chamberlin has well observed that
if an attempt were made to enumerate all our glacial lakes,
large and small, temporarily formed in valleys and basins slop-
ing toward the retreating border of the ice-sheet, they would
be counted "not by scores and hundreds, but by thousands."
July 1st and 2nd of last summer, two very clear and beau-
tiful days, were given to my examination of Glens Roy, Gloy
Spean, and their tributaries, and the cols over which the
glacial lakes outflowed. Coming by railway from Fort
William to Roy Bridge station, I thence walked up Glen Roy,
and up the Turret and Chomhlain valleys, its northwestern
tributaries, to the Gloy col: slept in a shepherd's cottage;
walked back to Glen Glaster, over its col to the Spean, onward
to loch Treig, and back to Tulloch,( formerly Inverlair ) sta-
tion; and thence returned by railway to Fort William. Ex-
cepting the westward and late extension of lake Roy down the
Spean valley below the junction of Glen Roy, all the district
- thus observed lies on the Glen Roy sheet (63) of the Ordnance
Survey of Scotland, which has the scale of a mile to an inch
and is contoured for each 250 feet of altitude. This sheet, in
accordance with the request of Milne-Home, includes detailed
mapping of the Parallel Roads.
Lake Roy began with outflow northeastward from the
head of Glen Roy into the river Spey, whose valley was earlier
uncovered from the receding ice-sheet. The col between the
Roy and Spey is 1,151 feet above the sea, this being the sur-
face of a shallow peaty swamp, which, filled a few feet above
the old river bed of outflow, occupies the water divide in the
continuous, mountain-walled valley. Along the distance of
about a mile thence to loch Spey the pass has a descent of only
nine feet. The highest wave-worn shore of lake Roy, record-
ing its extension w^hile otttflowing at this col, has an altitude
of 1,150 feet, very nearly, the upper and lower limits of the
perceptible wave erosion being, according to the Ordnance
Survey, at 1,155 and 1,144 ^cet. The lake at this level attained,
with the recession of the ice-sheet, a length of nine or ten
miles, to the north side of Bohuntine hill and Glen Glaster,
The Parallel Roads of Glen Roy. — Upliam. 297
where the highest shore terminates. The maximum depth of
the lake in this stage, east of Bohuntine hill, was 650 feet.
Its v/idth in the Glen Roy was mainly between a half and
three-fourths of a mile, and it was only slightly diminished in
width along this mountain valley by sinking to the later and
lower shores.
When the ice-sheet, in its general southwestward recession
from this mountainous region, laid bare the col at the head of
Glen Glaster, leading into the Spean valley, lake Roy was
lowered to that pass. For a short time, perhaps a few years,
this new outflow was {Stationary at a level of about 1,100 feet,
shown by a faint shore mark seen along a distance of about
two-thirds of a mile where the Roy valley bends northeast of
the Turret bridge. Winds blowing through the valley had a
longer stretch of the lake for raising its wav^ there than on
any other part of its shores. Elsewhere this beach line is
wanting or scarcely observable.
The Glaster col has an altitude of 1,075 ^^^t> being filled up
with peat several feet above its original hight Its belt of
shore erosion, constituting the middle one of the Parallel
Roads, lies between upper and lower limits of 1,077 and 1,062
feet. The lake surface was nearly at 1,070 feet, with wave
wearing in storms above and beneath that level. The earliest
outflow in the Glaster pass may have been upon its northeast
side about 30 feet above the central depression which was soon
afterward occupied when permitted by slightly farther retreat
of the ice. Or a barrier of glacial drift about 30 feet high
may at first have obstructed the valley close southeast of the
later col, where now such drift deposits partly remain, facing
the brooklet with steeply undercut front.
During the formation of the Glaster shore line the lake
extended about a mile farther down Glen Rov, and into Glen
Collarig over the*pass north of Bohuntine hill, than at its
earlier highest stage. Its maximum depth, at the lowest point
to which it extended, was nearly the same as before.
With the recession of the ice-sheet only one mile and a
half southward from Glen Glaster, around the west side of
Creag Dhubh, lake Roy spread into the Spean valley and fell
about 215 feet more, to the level of the col east of loch Lag-
gan, between the Spean and Spey valleys. This col has a
298 The American Geologist, May, isou
hight of 848 feet, being now cut probably several feet below
its level during the existence of the glacial lake. Shore
erosion makhig the lowest Parallel Road during this time of
latest and greatest extension of lake Roy was limited between
862 and 850 feet. The lake held nearly the level of 855 feet,
being 36 feet above loch Laggan, and having a maxinium
depth of about 550 feet at its most southwestern part, in the
Spean valley about two miles below Roy Bridge. The length
of lake Roy in its latest stage, while outflowing beyond loch
Laggan, exceeded twenty miles in the Spean valley with a
width of about a half mile easterly and nearly two miles at the
west. It reached up Glen Roy about ten miles, terminating
three miles below its col.
The three principal Parallel Roads, approximately at 1,150
feet, 1,170 feet, and 855 feet above the sea, which were the
shores of lake Roy in its stages of these different outlets, are
of nearly equal development. They are very narrow beaches
cut by the waves in the now grassy and heathery drift which
thinly overspreads the rocky mountain sides, and are best
seen from some considerable distance by the eye following
their level lines of brighter green than the general slopes.
Prof. Henry D. Rogers, after his visit to Glen Roy nearly
forty years ago, wrote of its Roads: "Seen in profile, as when
looked at horizontally, they resemble so many artificial hill-
side cuttings, the back of each terrace lying within the general
profile of the mountain slope, while the front or outer ^A%^ is
protuberant beyond it." Jamieson says: ''Each of the Paral-
lel Roads consists of a sort of terrace or shelf, generally from
40 to 70 feet broad, and sloping towards the middle of the glen
at angles varying from 5" to 30"."
The best point for obtaining an extensive and impressive
view of these shore lines from the Glen Roy highway is on the
small marginal moraine east of Bohuntine kill, looking thence
up the glen. Good photographs of this view are for sale at
Fort William. Much depends on having favorable light and
clear air for seeing these delicate shore marks most satisfac-
torily. Their small, though very well defined development,
when compared with the shore erosion and beach deposits of
the glacial lake Agassiz and with the modern great lakes of the
St. Lawrence, seems to me to betoken onlv a short duration
The Parallel Roads of Glen Roy, — Upham, 299
of lake Roy, perhaps no more than one or two centuries for
all its stages together. About a third part of its whole time
of existence, represented by the formation of the Glaster shore
line, elapsed during a retreat of the ice border across a dis-
tance of less than two miles.
Lake Gloy, which attained a length of about six miles,
with a width of one-fourth to three-fourths of a mile and a
maximum depth of about 700 feet, overflowed from Glen Gloy
into the Chomhlain and Turret arm of Glen Roy. The col is
1.172 feet above the sea, but it is filled up about six feet with
peat. The Gloy shore erosion lies between vertical limits of
1.173 ^^^ I J 56 feet, the surface of the lake having been at
1,166 feet, very nearly. Its single shore line is, I think, more
conspicuous than either of the Glen Roy Roads. The out-
flowing stream., during the highest stage of lake Roy, had a
descent of about 16 feet and a length of perhaps a third of a
mile.
liOth these glacial lakes were brought to an end by the
soiUhwestward retreat of the ice, when it opened the Gloy
and Spean valleys to the area of loch I.ochy in the Great Glen
of Scotland. Although that deeper and broader, nearly
straight glen or valley was still filled by the fast waning ice-
sheet on the southwest, it was wholly open northeastward past
loch Xess to the sea. Its present watershed has an altitude
only slightly exceeding 100 feet, across which the ice-held
lakes of the Gloy, Roy, and Spean valleys were plainly drained
away.
Excellent opportunity to trace the old shore lines is
afforded by the absence of trees or even bushes from nearly
all the country. But in many places the stumps and roots of
trees were observed in the peaty soil, where any rivulet had
cut to a slight depth. The destruction of the former groves
and woods here seems probably attributable to their use for
fuel, as in some almost entirely prairie areas of the upper
Mississippi basin.
Deltas of very small volume were brought into lake Roy
in its successive stages by several of its tributaries. All these
streams are short, and they had only a brief time for this work
during the existence of the glacial lake. Their later alluvium
carried into the glen is of far greater volume, as notably in
3CK) The American Geologist, May. ib08
two admirable alluvial fans sloping down on the east side of the
glen at one and two miles below the mouth of the river Tur-
ret. The massive drift accumulations which the Turret in-
tersects near its mouth, regarded by Jamieson as a delta, seem
to me better interpreted by Prestwich as a marginal moraine
of the ice barrier when it stood there, four and a half rtiles
west-southwest of the Roy-Spey col.
The next paper in this series will describe the many re-
cessional moraines seen between the head of Glen Rov and
Ben Nevis, and will present reasons (following Jamieson) for
regarding the retreating Scottish ice-sheet as the barrier of
the lake which formed the Parallel Roads.
TERTIARY AND QUATERNARY DEPOSITS IN THE
MAGELLAN TERRITORIES.
By Otto Nobdenbkjold, Upsala. Sweden,
During the two Antarctic summers, 1895-96 and 1896-97,
that I spent in the Magellan territories (in Terra del Fuego
and South Patagonia south of the Santa Cruz river) I con-
centrated my attention largely upon studying the most recent
deposits of those regions with especial regard to the possibility
of being able to trace any proof in them of a glacial period. It
is of the results of those researches in so far as they are
already to hand that this paper is intended to give a short
account.
Seeing in the first place that the general character of
the Tertiary deposits in South Patagonia has been the subject
of a number of recent papers embodying results of re-
searches,* and in the second place that the parts of the district
I visited are some of the poorest in the matter of fossils, I
*The principal works treating of these deposits, and which will
be drawn upon for quotations below, are:
A. Mercerat. Essai de classification des terr. sediment, de la Pata-
gonie australc, Ann. Mus. Buenos Aires, V, 105.
F. Ameghino. Geology of Argentina, Geol. Mag., Jan. 1897.
J. B. Hatcher. Geology of Southern Patagonia, Am. Jour. Sci.,
Nov. 1897.
Of great importance for these questions are also
Chas. Darwin. Geological observations in South America, London,
1876.
L. Agassiz. South American expedition, Nature, 1872, VI, 216.
Deposits in the Magellan Territories. — Nordenskjold, 301
was constrained to lay chief stress in my labors upon such re-
searches as should serve to establish the physical, in especial
the climatic, conditions during the period in question, and
upon collecting plant fossils that in many places occur in
strata belonging to the middle sections of the Tertiary forma-
tion, viz : the Supra Patagonian and the Santa Cruz beds.
Leaves belonging to the species of the genus Fragus arc
the commonest finds ; among them the most useful, probably,
is F. magelhaenica, described by Engelhardt as found in Punta
Arenas. This proves that the vegetation at that period had
the same character as at present. That the climate, how-
ever, must have been somewhat warmer seems proved by a
find that Nathorst has made among the Collections we brought
liome, viz : a broad-leaved species of Araucaria (group Colym-
bea) in Tertiary clay from Punta Arenas. That the climate,
however, must have been damper seems to be evident from
the fact that strata of coal and remains of a luxuriant vegeta-
tion have been come upon in localities where to-day no
arboreal vegetation occurs. Engelhardt, however, describes*
a portion of a palm leaf found in the place just referred to,
and comes to the conclusion that the climate at that time must
at least have been subtropical. That is, nevertheless, not
plausible, unless confusion of locality exists, the leaf probably
coming from some quite different deposit older than that
containing Fragus and Araucaria.
The most recent deposits in Patagonia that contain fossils,
so far as hitherto known, are the Cape Fairweather beds, de-
scribed by Hatcher. He collected from them specimens of a
mollusk-fauna somewhat poor in the matter of species and
submitted the same to Pilsbry for him to describe. The de-
scription he gives shows that the strata cannot be older than
Pliocene. They gradually yield place to the Patagonian
boulder formation above, the age of the latter being thereby
fixed at their earliest limit.
Relying on Darwin's description. Hatcher correlates the
Cape Fairweather beds with the Tertiary deposits at San Sebas-
tian bay in Terra del Fuego. From that place and its vicinity I
have brought home a large number of fossil plants and mol-
lusks. The latter have been consigned to the charge of Prof.
*Abh. Senckenb. Naturf., Ses. XVI, 629.
302 The American Geologist, May, ib»*
Steinmann for description. He writes that on a hurried ex-
amination he finds that they do not seem to bear any great
resemblance to the fauna Pil^bry treats of, but that he is not
prepared at present to give any opinion as to the age of the
strata.
In the most recent Tertiary strata in Terra del Fuego
veins of lignitic coal and vegetable remains are found in many
places, and one might assume that we had a fresh-water forma-
tion here, corresponding to the Santa Cruz beds in Patagonia.
In a specimen of a clay, however, from the Cullen river, de-
posited immediately beneath and in contact with glacial gravel,
the clay being in other respects free from fossils, Cleve has dis-
covered remains of a tolerably rich marine flora of Diato-
maceae; hence, it seems most probable that this clay is an
analogue of the Cape Fairweather beds;
The Tehuelche, or boulder formation mentioned above, is
not only the most peculiar of the deposits in Patagonia, but
it is also the one about the mode of whose origin the greatest
diversity of opinion has prevailed. The deposit is as much as
sixty metres thick, and plainly consists of stratified shingle
and gravel, sometimes mixed with sand. As the result of in-
vestigations made by Darwin, Doering, Sieniradzki, Am-
eghino and others, it has been supposed that this deposit ex-
tended uniformly over the whole of Patagonia — high plateaus
and lowlands alike — up to the Colorado river. The majority
of the investigators who have considered the question have
held the deposit to be marine; some, and Steinmann among
them, have connected it with the glacial period of these
regions, without, however, as a rule, expressing any opinion
as to the mode of its formation. Hatcher embraces the former
hypothesis by reason of the above-mentioned fact that the
shingle formation passes into the Cape Fairweather beds be?
low. As now formations similar to these beds would not at
present seem to have been come upon anywhere but at a
hight of from too to 150 metres above the present sea-level,
and in the immediate vicinity of the shore, the observation
made does not afford reasons enough to assume, for so late
a period, such an immense depression of the land, of necessity
nearly 1,000 m. at least. If this were so it would be strange
Deposits in tlie Magellan Territories, — Nordenskjold, 303
not to find any deep-sea formation on the lowlands, analogous
to the conglomerates on the shore.*
This fact has no further bearing upon the question of
whether the shingle formation is to be connected with a glacial
period. On the other hand, the probability of that being the
case has been considerably strengthened by the discovery I
made in Terra del Fuego of immense masses of gravel of an
.exactly similar character existing in immediate proximity to
the glacial boulder-clay described below. Moreover, in West-
ern Patagonia, in the district watered by the upper reaches
of the Coile river, I found intercalations in the shingle forma-
tion of undoubted glacial origin.
The supposition that commends itself most strongly to me
is that the shingle is formed by big rivers whose sources were
immense glaciers and which flowed through country with a
comparatively level surface, and hence, by reason also of
the vast deposits, often altered their courses. This view of
the case is the same as that propounded by von Haast as an
explanation of the strata occurring in the Canterbury plains,
New Zealand.t To appreciate the feasibility of this explana-
tion, one must call to mind the fact that all data concerning
the thickness of the gravel comes from the present-day river-
valleys. It is only there that sections in the gravel are to be
found. It is not even possible to establish whether this gravel
occurs over the whole of the plain, since there it is often cov-
ered over with later sedimentary deposits — ^**loess" — with in-
tercalations of sand and gravel. If we now assume that the
rivers of to-day have for the most part the same courses that
their mighty predecessors in glacial ages followed, we should
arrive at an explanation of the circumstance that the gravel
exists to such a great depth in the walls of the present river
valleys.
♦The statement made by Ameghino that intercalations have been
met with in the bowlder clay, containing the shell of an Ostrea "of the
same type as the Ostrea bourgeoisi," is very interesting, but is at the
same time so incomplete that no conclusions can be drawn from it.
Since the inquiries prosecuted by Hatcher it does not in any case
seem likely that it can have any bearing on the question of the age
of the formation.
*tJ. von Haast. The Geology of Canterbury and Westland, 1879.
JFurthermore also because if we assume t>vo separate glacial periods,
part of the gravel (to be) found in Patagonia probably belongs to the
formations in the second period.
304 The American Geologist Mny. isw
This formation, both in appearance and in locality, very
strongly reminds one of the nagel-flue formation that dis-
tinguishes the first descent of the ice in the Alps, and it would
seem highly probable that the mode of origin in Patagonia
is the same, though there the phenomenon has been of much
greater extent.
The boulder formation is most extensive in Central Pata-
gonia ; in the southernmost part of the continent and in Terra
del Fuego it is of much less importance. In those parts it
is replaced by another not less interesting formation that can
be very conveniently investigated at many points on the east
coast of Terra del Fuego, for instance at cape San Sebastian.
The "barranca," over sixty metres in hight, consists through-
out of an entirely unstratified clay containing, in the utmost
disorder, masses of angular-shaped stones varying in size from
the smallest imaginable to great blocks of a volume of several
cubic metres. Among these stones there are many that dis-
play traces of glacial polish and stria. Fossils are not found*
with the exception of occasional broken shells of a furritella,
common in the underlying Tertiary deposits; these are pre-
sumably not original here. It cannot be questioned that this
boulder clay is formed in the same manner as the correspond-
ing deposits in the northern hemisphere, and that it consti-
tutes the ground moraine of a thick layer of land-ice. f
On the coast further north numerous irregular, often len-
ticular intercalations of gravel and sand occur. These do not
contain either any traces of fossil remains. They are notice-
able, however, for a cross-bedding, extremely usual and plainly
to be seen. This is characteristic of river-glacial deposits,
and the sand is frequently permeated with small faults. Both
above and below the boulder clay irregular layers of sand
and gravel are often found. Still further north the boulcfcr
clay itself forms an intercalation in a thick shingle formation
on the plateau ; it often takes the form of two or more narrow
somewhat irregular layers, one above the other.
This boulder-clay gives origin to a peculiar form of land-
*Not even Diatomaceae or other microscopic organisms.
tOf the blocks the majority consist of rock varieties from the Cor-
dilleras; of these many have proved under the microscope to be identical
with the white granite from the Western islands.
Deposits in the Magellan Territories, — Nordenskjold. 305
scape, with numerous low, rounded hillocks, in which small
mounds abound, on either side of the two huge valleys that
here intersect the country, viz : Magellan straits and the San
Sebastian valley. On the high ground between these two
valleys and on the hights to the north and south, the boulder
clay is only met with up to a certain elevation. The loftiest
of the high plateaus in Patagonia and Terra del Fuego alike
are covered with shingle.
In the eastern parts of Patagonia the ground moraine has
only been met with in typical form in the vicinity of the
Magellan straits. Near the foot of the Cordilleras typical dis-
tricts are here and there to be found — for instance, north of
lak^ Sarmiento,* consisting of irregular but extensive ter-
minal moraines covered at intervals with rocks. In other
places the moraine formation is replaced by another, for in-
stance in the extensive lowland that stretches east of Dis-
appointment bay and then continues northwards to expand
again at the south base of the Bagnales mountains.
The ground throughout this district consists of sandy clay,
more or less plentifully supplied with stones that are often
6dged and occasionally scratched. It almost al>Vays displays
a clearly marked stratification and occasionally gives place to
strata of typical sedimentary clay. None of these formations
contain either macroscopic or microscopic organisms — in itself
a strong reason for assuming glacial origin. They have un-
doubtedly, however, been formed under water, but in close
enough proximity to the edge of the ice to allow quantities
of stones brought down by floating ice to be embedded con-
temporaneously with the silt. Whether the deposition took
place in the sea or in inland lakes in the absence of organisms
has not been able to be established. If the former was the
case the sea must have been at least 100 to 150 metres higher
in the glacial period than now.
Reliable proof of land elevation at a late date is also forth-
coming in other parts ; the elevation is not, however, so great
as has hitherto been supposed. On the south side of Useless
bay at the hight of fifty-five metres there is a terrace con-
stituted of a former beach; numerous large blocks of white
•♦Cf. the sketch-map published in the Geographical Journal for
October, 1897.
306 « The Amefican Geologist May. i89b
granite rest on it. Hence this beach, too, is to be attributed
to the* glacial period. At about the same elevation, between
fifty and seventy metres, similar terrace lines are to be found
at many places in the archipelago, pointing to a higher water
mark in earlier times.
Below this mark there are to be found in many parts of
the valleys stratified formations usually of clay. These are
vary scarce in fossils, though they have on examination been
proved to contain marine Diatomacese and sponge spicules.
A remarkable feature of the whole district is the immense
size and development of the valleys. In relation to the rivers
flowing through them, these valleys are mostly broad, with lofty
and steep though not perpendicular walls. Down bHow,
through a quite level country, the river slowly makes its way
in complex snake-like meanderings. This state of things
recurs in the mountain district of the Cordilleras and in the
Quaternary and Tertiary elevated plains of the Pampas.
To now pass the development of the Magellan Territories
during the most recent geological phases in review :
During the Santa Cruz period that, according to recent
inqjiiries corresponds approximately with the Miocene period
in the north, a wide continent already existed here, probably
forming a low, marshy countfy with numerous fresh-water
lagoons on its surface. The country was overgrown with
extensive forests, at that time as at the present principally
species of the beech, but also with Araucaria and other varie-
ties. These forests were the abode of strange beasts, Hom-
unculus, Xylotherium, Typotherium, Macrauchenia and many
others. The climate was warmer and more humid than at
present, though by no means tropical.
Thereupon, came in the Pliocene period a depression ; the
present coast territories, at any rate, were below water, in
which at that time the fauna of the Cape Fairweather dwelt,
forms, of which some still exist in those regions, while others,
for instance certain large varieties of Ostrea, are extinct.
It is possible that contemporaneously an elevation took
place in the west, for otherwise it is difficult to explain the
phenomenon that thereupon ensued. Enormous quantities oF
ice collected in the Cordilleras; they did not, it is true, stretch
far across the plain to the east, but they brought down, in the
Deposits in the Magellan Territories. — No^denskjold, 307
rivers that arose when they began to melt, great quantities
of gravel and boulders right to the shore of the sea.
Thereupon succeeded an intervening space. Whether we
are to suppose it only a temporary retreat on the part of the
ice or if it was really an inter-glacial period cannot be de-
termined, since there are no fossiliferous deposits known left
by it. The intimate connection that seems to. exist between
deposits belonging to the first arid those belonging to the
second glacial period argues in favour of the former suppo-
sition. In any case the between-period was of considerable
duration, for the majority of the great valleys of the district
arose by the process of erosion while it was in progress. Thus
the most important of those valleys, the Magellan straits (east-
ern section) and the San Sebastian valley, date from this
period, possibly also Gallegos valley. At the same time the
great lowland districts, now partially covered with water,
were formed ; they extend from the eastern base of the Cor-
dilleras and now constitute: Broad Reach (a section of the
Magellan straits). Disappointment bay, the plain that lies
south of Bagnal mountains, etc. The moraines and other
deposits of the first glacial period, that undoubtedly were to
be found here previously, were thereby destroyed.
Once more the ice advanced. It is probable that the
blocks of ice were vaster than before ; at the same time it was
now more possible for it to extend over the broad newly
formed vallevs. The southernmost of these, the San Sebas-
tian valley, was occupied by a gigantic "mer de glace," that
along with its outlying neve-fields had an area of 20,000
square kilometres at least, ^nd probably was joined to the
almost equally extensive glacier that existed in the eastern sec-
tion of the present Magellan straits. Further north no such
glaciers have been discovered. In their place on the great
lowland, east of the Cordilleras, between 50° 50' and about
52° south latitude, a body of water containing drift-ice ex-
tended, probably a lake dammed up with ice, or possibly an
arm of the sea.
It is established that the sea, at a time when it was full
of floating ice-bergs, stood at least sixty metres higher than
at present. That time, however, need not necessarily be so
very far removed from the present. Many reasons, indeed,
308 % The American Geologist, May, ihw*
seem to point to the glacial period having lasted down in
these regions to. from a geological point of view, quite a
recent date, one of the most telling being the great poverty
in both the fauna and flora in T erra del Fuego in comparison
with Patagonia. It is difficult to explain why quantities of
mammals, reptiles, insects, phanerogamous plants, etc., that
still survive on the north shore of the Magellan straits, that
are onlv three kilometres in width, are non-existent in Terra
del Fuego and are represented by other varieties, unless we
assume that outward circumstances, presumably a cold
climate, prevented their coming hither until recent times.
Thus, so far as at present known, the development in a
geological sense of the Magellan territories proves to present
a remarkable parallel to that of lands in the same relative lati-
tude in the northern hemisphere. It is not less evident that
in many respects the state of the case is the same here as it
is in New Zealand, even though we are not yet in a position
to draw anything like a complete comparison between the
two portions of the globe. It is not possible for me in this
short paper to bring forward a complete theory in explana-
tion of these striking analogies between regions so far apart.
It is a known circumstance that the climate in the northern
hemisphere during the central part of the Tertiary epoch was
warmer than now, though the ratio was not everywhere the
same, and the same would seem to hold good for the southern
hemisphere also. Towards the close of the same period a
general deterioration in the climate ensued in all the lands
round the two poles known to man, and !n Europe, North and
South America, in New Zealand, and in numerous hill dis-
tricts. The result was the formation of vast masses ol ice.
How far this can have come about contemporaneously in all
parts it would be difficult to determine. But even if it was
only approximately at the same time in the various regions,
yet all views of the matter that would explain these phenomena
as purely local must appear highly improbable, and the same
may be said of the hypothesis set forth by Croll that premises
that the glacial periods alternated in the north and south
hemispheres with, in geological computation, but short in-
tervals between, furthermore the theory about the change of
position in the earth's axis, in case we regard these variations
Deposits in the Magellan Territories, — Nardenskjold. 309
as regular in their reappearance. For if we know that glacial
periods have occurred in so many parts of the world's surface,
far distant from each other within one and the same^ from a
geological standpoint, short epoch, all the three hypotheses
mentioned, that concern themselves with forces that must
always have acted throughout the whole of the geological
periods, to be probable premise that a number of cold periods
must have existed even during the preceding and considerably
more prolonged period of the Tertiary epoch. Since now no
manifest traces of that have been come upon in any region
the niost plausible view is one that endeavors to explain the
glacial period as beifig due to some temporary cosmic phe-
nomenon that exercised its influence uniformly over the whole
earth. That phenomenon had not strength enough to sub-
induce a covering of ice throughout the polar lands ; for East
Siberia had none. On the other hand it is open to doubt
whether it occurred suddenly and lasted but a short time com-
paratively, and whether it thus caused a simultaneous glacia-
tion in all districts where it was bv reason of the conditions
of temperature and humidity possible to do so, or whether, as
is more likely, its effects were only gradual but prolonged,
possibly through the whole of the Pliocene and Pleistocene
periods, but that it was too Ineffectual to cause a genuine
glacial period, save in places where favourable local circum-
stances were at hand to promote it. In this connection it is
not impossible that the facts, upon which the Croll hypothesis
builds, may have a considerable importance.
What that cosmic phenomenon can have been we at pres-
«
ent do not know. I cannot, however, refrain from mention-
ing, as one of the most plausible views hitherto put forth, that
of Arrhenius* and Hogbom, viz: that the cold climate during
the glacial period was caused by a lowering of the percentage
of carbon anhydride in the air, while the warm climate during
the earlier part of the Tertiary period was due to a corre-
sponding increase of the same.f
♦S. Arrhenius, Phil. Mag., S. 5, vol. XLI (1896) i., 237. Cf. also
T. C. Chamberlin, Journal of Geology, V, 653.
t A more complete discussion of the geology of the Magellan terri-
tories is to appear in **Wissenschaftliche, Beobachtungen wahrend
der Schwed. Expedition nach den Ma^ellanlandem," now in the press.
310 The American Geologist May, law
CHAMPLAIN SUBMERGENCE IN THE
NARRAGANSETT BAY REGION.
By MyaaN L. Fai<LBR, Bostoo, Mass.
The object of this paper is to show the improbability of
certain assumptions which have been made as to the relative
hights of land and sea during the deposition of some of the
sand-plains of the Narragansett bay region of Rhode Island
at the time bf the final retreat of the ice sheet.
The considerable elevation of the higher terraces of the
Connecticut, Thames and other rivers of southern New Eng-
land above the level of their present fiood-plains was at
first tacitly accepted as pointing to a 'corresponding Cham-
plain depression of the region below the present level. Dana,
however, forcibly opposed the Acceptance of such evidence
as giving any absolute indication of the amount of depression.
He argued that the high waters of the river valleys were due,
in a large measure, not to the depression of the land, but to
the enormous floods of water set free by the rapid ablation
accompanying the final retreat of the ice sheet when, as he
has put it*, "centuries of precipitated moisture were let loose
at once." The excessive amounts of water, in connection
with the natural obstacles in the shape of abrupt bends, con-
stricted valleys, junction with htrge tributaries, etc., which are
common to all the rivers of southern New England, is suffi-
cient, few will deny, to account in an important degree for
the great differences in the altitudes of the Champlain and the
present flood plains. Ice dams, as urged by the author
quoted, may also have been an efficient adjunct to the natural
obstacles just mentioned. The fact that even at the present
day at Hartford, some fifty miles above the mouth of the
Connecticut river, the difference between high and low water
has often exceeded twenty-five feet, lends considerable weight
to the assumption.
In recent years Mr. J. B. Woodworth, in connection with
the work of the United States Geological Survey, has made
a careful study of the modified drift phenomena of the region
of Narragansett bay, and has published f a description and
map of the various sand-plains marking the different stages
*Am. Jour. Sci., 3. vol. X, p. 437.
tAmer. Geol., vol. XVIII, pp. 150-168, 391-392.
Submergetice in the Narragansett Bay. — Ftdler, 3 1 1
of the ice retreat in that vicinity. He found that the hights
of the sand-plains indicated water standing at levels varying
from twenty up to 150 feet above the present sea level. The
level of the higher of these sand-plains, as for example, those
of the Wickford stage, **is obviously determined by local
topographical conditions."* In the case of the plains of the
Greenwich Cove and Harrington stages, where there is evi-
dence of the deposition of delta-like sand-plains **with the
water as high as 50 feet above the present sea level," f the
topographical conditions afford no explanation.
The periods of high water during the deposition of these
plains seem to have been followed, in each case, by a fall of
50 feet or more at their completion. If ice remnants had re-
mained in the passages of the lower bay, as Mr. Woodworth
suggested J in his earlier paper on the retreat of the ice sheet
in the Narragansett bay region, the deposition might readily
be conceived as taking place in the temporary lakes formed
by such obstructions. In his later paper, however, he admits
that "ice dams in Glacial Narragansett bay appear incapable
of affording an explanation,"§ and concludes that the changes
of level "are analogous to those of our large inland rivers,
and come under the head of flood changes," thus agreeing
with the views set forth ij by Dana in regard to the upper limit
of river border formations ; namely, as already indicated, that
the hights of the waters had no direct relation to that of the
ocean, but were determined by the enormity of the floods
aided, possibly, as suggested by Woodworth, by the "gorg-
ing" action of floating ice in the lower bay.
The difficulty of accounting for the pitch of the upper
surface of the waters of the glacial bay under this hypothesis
was appreciated by Mr. Woodworth, but the full extent of
the requirements demanded by the postulated flood was evi-
dently not realised. In the opinion of the writer, the ex-
planation offered cannot be maintained. The causes so effi-
cient when acting in the comparatively narrow valleys of our
*Loc. cit., p. 154.
tLoc. cit., p. 391.
JLoc. cit, p. 168.
§Loc. cit., p. 392.
IIMan. Geol. 3rd Ed., p. 551.
312 The American Geologist. May. uw
New ^England streams appear to be adequate to account for
but a small part of the fifty feet which needs must be ex-
plained in the broad and comparatively open Narragansett
bay. It is a noticeable fact in this connection that even at
Providence, on the narrow northern extension of the bay, the
level of the water is unaffected by the highest spring floods,*
forming in this respect a marked contrast with the Connecti-
cut, Housatonic and Thames rivers.
Evidences.
General Reasoning. — Evidences of a Champlain sub-
sidence in the shape of elevated shore-lines and of fossiliferous
deposits are found in a fairly continuous chain surrounding
New England. The subsidence was least ia the south, the
evidences of the raised beaches along Long Island sound and
eastward indicating, according to Dana, a submergence
amounting only to some fifteen or twenty feet. On the. coast
of Maine, as indicated by elevated shore lines and fossils, the
depression varied from 230 feet to nearly 300 feet, the greater
being to the north and east. At Montreal, as shown by
Dawson, the depression amounted to from 500 to 600 feet.
On the west, along the valleys of the Hudson river and
lake Champlain, the submergence, according to F. J. H.
Merrill, amounted to 335 feet at Albany, 370 feet at the
southern end of lake Champlain and to 500 feet at St. Albans
(Baldwin). That the interior of New England partook of the
same movement of subsidence is shown by the high river
terraces everywhere abounding, and indicating, even after due
allowance has been made for the flooded condition of the
rivers at that time, an altitude much below that at present
existing.
Montreal is almost exactly 300 miles north of Long Island
sound, hence the average increase in the amount of the sub-
mergence to the north was i 2-3 feet per mile. If, as urged
by Dana,f the submergence along the coast at the mouth of
Narragansett bay was fifteen feet, then the hight of the water
at Providence, twenty-eight miles distant, should have beeli
forty-seven feet above this level, or sixty-two feet above the
♦Am.. Jour. Sci., 3, vol. X, p. 435,
tLoc. cit., p. 434.
Subntergetice in the Narragansett Bay, — Fuller, 3 1 3
present sea level. It should be noticed that these figures
represent a minimum subsidence, being based on the figures
given by Dana — the foremost advocate of a slight Champlain
subsidence in southern New England. Even this amount,
however, could be made to meet, to a considerable extent, the
requirements demanded by the sand-plains described by
Woodworth.
Competency of Outlets, — The level of the ocean at the
time of the deposition of the sand-plains being, as held by
Woodworth, approximately as at present, an increase in the
hight of the waters of the upper part of the bay could only
take place when the capacity of the outlets to the ocean was
less than the capacity of the combined glacial streams entering
at the same time. It is my object to show that, in kll prob-
ability, there were no floods of sufficient magnitude to cause
more than a very slight rise, and certainly none sufficient to
account for the rise of fifty feet demanded.
On Mr. Woodworth^s map of the' glacial deposits in the
vicinity of Narragansett bay he gives, in addition to the higher
plains laid down in water held up by local topbgraiphic con-
ditions, eight plains with crests from fdrty to sixty feet eleva-
tion above tide. They are distributed from the vicinity of
Wickford Junction on the south to Harrington on the north.
In most of these plains the evidence as to the nature and
size of the streams by which they were laid down is unsatis-
factory, but the Harrington plain, which is one of the largest,
has been shown to have been deposited by a single stream
having a width, as indicated by its esker, not exceeding 150
feet. Our knowledge of the size of glacial streams in Alaska
and Greenland leads to the belief that the depth of the water
in such a stream could not have exceeded twentv feet. In
order not to under-rate the importance of the stream, how-
ever, I have, in calculating the area of its cross section,
assumed that it had a width, not of 150 feet, but of 200 feet,
and a depth, not of twenty feet, but of fifty feet. The area
of the cross section of such a stream, it will be seen, is 10,000
square feet.
There are three outlets to the sea from the upper Nar-
ragansett bay, one on each side of the Conanicut island, and
a third between Aquidneck, or Rhode Island, and the main-
3M The AmJericofi Geologist. May, i898
land. This latter is to be regarded rather as an outlet of the
valley of the Taunton river and Mt. Hope bay than of the main
portion of Narragansett bay, with which it is, in fact, only
indirectly connected. It is, therefore, set aside as havmg
little or no bearing upon the level of the waters of the bay.
The outlet to the west of Conanicut island, known as the
Western passage, will first receive attention. According to
chart No. 353 of the United States Coast and Geodetic Survey,
the passage is narrowest when opposite Fox hill, having there
a width of almost exactly a mile. The present average depth
computed from the same source is thirty-six feet. The area
of its cross section is, therefore, 190,000 square feet, or nine-
teen times as great as that of the glacial stream which laid
down the Barrington plain. In other words, the Western
passage alone could carry off the floods of nineteen such
streams without appreciable increase in the hight of its waters.
Considering that of the eight plains mentioned, not more than
three at the most can be correlated as belonging to the same
stage of ice retreat, there certainly seems no cause here for any
increase in the hight of the waters.
If this is true of the Western passage, it is even more so
of the Eastern passage. Referring again to the chart, we
find the narrowest point of this latter passage is along a line
running southeast from fort Dumpling, the width being 3,300
feet and the average depth 120 feet. The area of the cross
section is, therefore, some 400,000 square feet, or forty times
as great as that of the glacial stream mentioned. Both out-
lets remaining open, an increase in the hight of the' waters
could only take place when sixty or more streams of the size
of the one laying down the Barrington esker entered the bay
at one time. There is certainly little evidence that such was
the case.
It may be argued, however, that many of the glacial
streams entering the bay are unrepresented by sand plains.
Granting this to be so, it is yet possible to show that with the
increased surface slope of the flood consequent upon any
increase in the hight of its Avaters, the discharge would rapidly
assume proportions exceeding all possibility of supply.
Enormity of Flood Demanded. —-The distance from Green-
wich cove to the open sea at the southern end of Conanicut
Submergence in the Narragansett Bay, — Fuller, 315
island is fifteen miles. The plain in the vicinity of the cove
indicates water standing at least fifty feet above the present
sea level. It follows, therefore, that the average surface slope
of the assumed torrent would have been at least three and a
third feet per mile. Taking this as a basis, the velocity and
discharge of the two principal outlets of Narragansett bay
were computed according to the formula given by Hum-
phreys and Abbot.* The widths and depths of the outlets
in their flooded condition were calculated from the sound-
ings and contours of the chart before mentioned. The results
obtained were as follows :
Eastern Passage.
W= widths 1 1,500 ft. A=area of cross section==Q58,400 sq. ft.
p = wetted pcrimeter=Wx i.oi5=*i 1,672
s = Sin of stope = "f === ^^q "^ .0006313
r = hydraulic mean radius = ^ = 41.36
V = velocity. D = Av = discharge.
V = ( [225 r]'*— s \ .0388 ) 2 = - 13.95
D (approx.) == 13,370,000
Western Passage.
W= 9,600 A = 388,800 p= 9.744
8 =.0006313 r==20.ii v = 9. 574
D (approx.) = 3,722,000
Combined discharge = 17,092,000 cubic feet per second.
The combined discharge, as has been seen, would have
reached the enormous figure of over 17,000,000 cubic feet per
second, or nearly twenty-eight times the discharge of the ^Tis-
sissippi river, and equivalent to 280 glacial streams of the size
mentioned. \
Great as this flood appears, however, it is considerably less
than would actually have been the case if the Champlain
waters stood at a hight of fifty feet above the present level
in the vicinity of Greenwich cove. The discharge at any
point on the bay below this cove (which marks the probable
♦Report upon the Physics and Hydraulics of the Mississippi River,
(Professional Papers of the Corps of Topographical Engineers, U. S.
Army). Edition of 1878.
TThe velocity of the glacial stream as indicated by its pebbles, is
taken as six feet per second.
3i6 Tlu American Geologist. Uay. i88h
southern limit of tributary streams of any importance) would
necessarily have been the same. It follows, therefore, that in
the constricted outlets a considerably greater velocity, and
consequently a greater slope, would have existed.
In calculating the velocity and discharge from this stand-
point, the portion of the bay south of Greenwich cove was
divided into two sections; the northernmost, some seven miles
long, comprising the open reaches of the bay lying between
Greenwich cove and the northern end of Conanicut island;
and the southernmost, about eight miles long, comprising the
Eastern and Western passages. The data, together with the
calculated velocities and discharge, are given below:
Upper Bay.
W ==35,000 A = 1,746,850. p = 70,525.
s= 35 in. == .0005524 r = 24.77 v=ii.i8
Discharge (approx.) == 19,525,000.
Easteru Passage.
W= 11,500 A=975,ioo. p=23,i72.
s= 44.376 in.=.ooo7oo4 r = 42.08 v ^= 15.53
Discharge (approx.) = 15,143,000.
Western Passage.
W= 9,600 A = 402i75o. p -= 19*344
s = .0007004 r = 20.82 V = 10.88
Discharge (approx. ) = 4,382,ocx).
The enormity of such a Hood can only be appreciated by
comparison. It would be equal to a stream having a dis-
charge six times as great as the Amazon, thirty-two times as
great as the Mississippi, 140 times that of the Nile, 190 times
that of the Ganges, and from two to three times as great
as the combined discharge of all the rivers of the earth at the
present time.
Ablation Demanded. — ^The impossibility of such a flood
is clearly shown by the great amount of ablation which would
be required to furnish the immense volumes of water de-
manded by the theory. The conditions favorable to a con-
centration of glacial drainage in Narragansett bay were no
more favorable than at a dozen other points in New England,
and the streams entering at this point could have comprised
only a small part of the total number in the region in ques-
Submergence in the Narragansett Bay. — Fuller, 317
tion. The easternmost lobe of ice covering the state of Maine
and terminating along a line reaching from cape Cod east-
ward to Georges shoal was, in its lower portion at least, almost
entirely independent of the ice to the westward, and possessed
without doubt a drainage system complete in itself. It could
have furnished no part of the waters discharged through Nar-
ragansett bay.
The area of New England, excluding Maine, is approxi-
mately 33,500 square miles. Assuming the whole to have
been covered with ice, a melting of 349 cubic feet of ice per
day for every square foot in this area would have been re-
quired to furnish the flood demanded.
It should not be forgotten, however, that the conditions for
great floods were just as favorable in the valleys of the Housa-
tonic, Connecticut and Thames, and the area drained by the
streams entering Narrangansett bay would not, in all prob-
ability, have been more than a quarter of the area mentioned
above. Assuming the actual area drained to have been equal
to that of the state of Massachusetts (8,315 sq. m.), we find
the ablation required to meet the demands of the flood reach-
ing the enormous figure of 14.1 cubic feet per day for each
square foot of surface.*
Comparatively few measurements of the surface ablation
of glaciers have been recorded, but enough is known to show
conclusivelv that at the outside, it cannot be more than a
few inches per day, Reid, in his report on "Glacier Bay and its
Glaciers"fstates that during the cloudy and rainy weather of
the month of July the surface melting varied from 1.6 inches
to 2.5 inches per day, while on a clear, bright day it reached
as high as 2.75 inches per day. When it is remembered that
during the Alaskan summer the thermometer often mounts
well up towards the 100° mark, it will be readily seen that
under no combination of circumstances could such a melting
as that postulated in the preceding paragraph take place.
♦If, instead of assuming the whole of New England to have been
covered at this stage of the ice retreat, we should regard the margin
as occupying the position assigned by Upham (Amer. Geol., vol. XVI,
plate v,) to the Toronto boundary, the area supplying water by abla-
tion would be much decreased, and the amount of melting required to
meet the demands of the hypothesis would be even more enormous
than that given above.
ti6th Ann. Rept. U. S. Geol. Surv. part i, p. 450.
3i8 The American Geologist, May, i898
Transporting Power, — ^Additional evidence against the
existence of such a torrent as has been described is found in
the size of the material of which the sand-plains are com-
posed. The predominating material is sand, and could only
have been deposited in a current moving at a rate of less than
one foot per second. Further back, and nearer the point of
emergence of the glacial stream from the ice, the material
becomes coarser, the sand giving place to fine gravel and
indicating, perhaps, a current of two feet per second. Still
nearer the head of the plain gravel is found indicating currents
of three, four or even five feet per second, while in the esker
left by the stream, as for example, the Barrington stream,
stones up to six inches in diameter, and indicating a current
of a little less than 6.4 feet per second, were observed.
The evidence of the material thus fixes a maximum to the
actual velocities of the waters in which the sand plains were
laid down. With this velocity the velocities necessitated by
the assumptions of glacial floods as a cause for the hight of
the waters in Narragansett bay in Champlain times, forms a
striking contrast. As we have seen, the highest velocity in-
dicated by the material of the sand plains is about six feet
per second, a velocity which would be capable of moving
almost exactly 17 pounds. The actual velocity of the postu-
lated flood would, in the region of the sand-plains be 11. 18
feet per second, and would be sufficient to roll along boulders
505 pounds in weight, or thirty times the size of the largest
material of the sand-plains. In the Eastern passage the cur-
rent would have been sufficient to have transported a boulder
over two tons in weight, or about 240 times the size of the
material at the head of the plains.
Problem of Ice Barriers. — An increase in the hight of the
waters by simple flood demands torrents far beyond the range
of possibility. Ice barriers, in the sense ordinarily used, are
admittedly out of the question. Only barriers formed by the
temporary gorging action of floating ice need, therefore, be
considered.
The ice if in motion, would undoubtedlv furnish an abund-
ance of icebergs wherever it came in contact with the water.
It is, however, a well known fact that such was not the case
at the time of the deposition of the sand-plains » distortion.
Sub merge fice in the Narragansett Bay, — Fuller, 319
crushing, or thrust faulting in the beds laid down against the
face of the ice being almost unknown, and indicating that in
practically every instance the ice was perfectly stationary.
Occasional blocks were undoubtedly broken off, as is testified
by ihe rock fragments dropped from them into the finely
stratified material over which they floated, but the conditions
along the front of such a stagnant ice sheet were certainly un-
favorable to any considerable discharge of floating ice.
Even where barriers of floating ice form in our narrow
rivers they seldom last but a few days. Certainly an ice bar-
rier of this type in the lower Narragansett bay would have
been too transitorv to have withstood the force of the enor-
mous body of water pressing against it from behind for a
period long enough for the deposition of a large sand-plain,
however rapid this may be.
Summary. — In the foregoing pages the aim has been to
follow to the logical end the results which must, of necessity,
follow the disbarment of the submergence theory and the
acceptance of the theory of glacial floods as an explanation
of the altitude held by the waters of the Narragansett bay
region during the final retreat of the ice. Evidences of a
Champlain submergence along Long Island sound of at least
fifteen feet are indisputable, and the actual amount was prob-
ably somewhat greater. The difficulty, however, of correlat-
ing this submergence as to exact time with the deposition
of the Narragansett sand-plains detracts considerably from
the value of arguments from such general evidence.
The level of the sea remaining substantially as at present,
as is assumed by the advocates of the glacial floods, no con-
siderable increase in the hight of the waters of the bay could
take place unless more than sixty glacial streams of the size
of the Barrington stream entered the bay simultaneously.
The united volumes of these streams would be equal to six
times the volumes of discharge of the Mississippi river. But
the actual rise to be explained is at least fifty feet. This
would necessitate, as has been shown, the discharge into the
bay of a flood amounting to over 19,500,000 cubic feet per
second, an amount requiring the ablation of at least 3.49 cubic
feet of ice, and probably of 14.1 cubic feet per day, for every
square foot of its drainage area. Such a torrent would have a
320 The American Geologist May, i898
transporting power of from 30 to 240 times that indicated
by the coarser materials of the sand-plains.
The existence of such floods is untenable, as must also
be t/te theory which demands them. Recourse to the theory
of the existence of barriers formed by the gorging action of
floating ice is unavailing, for the conditions during the retreat
of the ice sheet were manifestly unfavorable to their forma-
tion. Even the complete closing of one of the passages
would, moreover, affect but little the conditions of the flood.*
Conclusion. — The failure of the glacial-flood and the ice-
barrier theories to afford a satisfactory explanation of the
phenomena in Narragansett bay brings us by the process of
elimination to the alternative theory of submergence. ITie
fact that the great over-wash plains on the south side of Cape
Cod were undoubtedly of subaerial formation, has had the
effect of causing many of the workers in this region to dis-
regard the evidences of submergence, which are certainly
quite manifest in places and to magnify the evidences to the
contrary.
The plains of the outer arm of Cape Cod were certainly
deposited in standing water, but whether the deposition took
place in the sea or in a body of fresh water pond'ed against
*the moraine, f is a matter of dispute. The writer believes
strongly in the former, the low and broken character of the
moraine — especially in that portion lying in the vicinity of
the sand plains, where perfect continuity is most essential —
being most unfavorable to the theory of ponding. But what-
ever doubt there may be as to this point, there can be none
in regard to many of the plains of Buzzards bay. The case
here is perfectly clear and can only point to a submergence
amounting, apparently, to at least forty feet. It was this evi-
dence which first led me to take issue with the views of sub-
mergence held by Davis, Woodworth and others. J That I
♦The actual decrease in discharge which would have been brought
about by the complete closing of the Western passage would have been
only about 1,200.000 cubic feet per second, or some 6.5 per cent.
fA. W. Grabau, Science, n. s. vol. X, p. 334-5.
J The views here advanced as to submergence in the regions of
cape Cod and Buzzard's bay were first set forth in an unpublished
essay on the "Modified Drift of Cape Cod" which received first award
in competition for the Walker prize offered by the Boston Society of
Natural History for 1897.
Review of Recent Geological Literature, 321
have based the arguments of this paper upon Naragansett,
rather than upon Buzzards bay, is due to the fact that it is
only in the former case that any detailed description of the
sand plains has been published.
The theory of submergence would be much simplified in
its application ' to the Narragansett bay region if it were
possible to regard the Greenwich Cove and Barrington stages
as contemporaneous. This Mr. Woodworth regards as im-
probable. The irregularity of the ice .margin demanded under
these conditions is no more than that shown by plains in
other localities, and is at least within the range of possibility.
The tendency to long north and south depressions held open
by the ice in the region in question is by no means unfavorable
to the theorv.
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
The Geological Structure of Shantung {Kiautschou) with particular
reference to the deposits of useful minerals, [Der geologise he Bau von
Schantung [Kiautschou) mit besonderer BerUchtigung der nutzbaren
Lagerstdtten.] By Ferdinand v. Richthofen. (Zeitschrift flir prak-
tische Geologis, pp. 73-84. March, 1898.)
This article by privy councillor Pr. Ferdinand von Richthofen upon
the economic geology of the Shantung peninsula of China is of especial
importance at the present time because of the recent acquisition of the
part of ICiaochau by Germany. From this article we take the following:
The province of Shantung was visited by Ferdinand v. Richthofen
at the beginning of his travels in China in the year 1869. No geological
investigations had been made prior to that time, and since there was
also no reliable topographical map he was compelled to make one him-
self. The scale of Richthofen's map is 1 1437,000. It also appears on a
smaller scale in his atlas of China in which Shantung appears on pages
I to 4 and 53 and 54.
The province is chiefly level ground, a part of the great plain of
China, only about 2/7 of its area being mountainous. The mountain
chain surrounds the entire peninsula and extends westward across it
forming an island-shaped area enclosed by plain and sea. The great
plain is an eruptive table-land and the underlying rocks are of unknown
age. The surface features are sculptured by the Hwang-ho and other
streams, each of which has at some time been one of its tributaries.
322 Ttie American Geologist, May, i«98
The great plain is an eastward sloping delta or alluvial deposit of this
great river system.
The Wei river in its northward course divides the mountain region
into two portions geologically and orographically distinct from each
other. The elevations are not of much magnitude. The Tai-shan in the
western part reaches the hight of i,6co meters with occasional ridges
in its vicinity 1,200 to 1,300 meters high. East of the river the eleva-
tions are lower, but the mountains are precipitous and wild. A chain
of mountains, much cut into. by deep arms of the sea, follows the south-
ern coast of the peninsula. Between the foothills of the Lauschan with
its elevation of 1,090 meters and the western continuation of the range
lies Kiaochau bay, a circular basin 26 kilometers in diameter and with
a depth of more than 40 meters of water.
Toward the north from here there extends a broad gently undulating
lowland reaching the northern coast of the peninsula. It extends also
far toward the east into the mountains, but consists of decomposed rock-
material rotted down in place rather than of alluvium. This region
supports the most prosperous and populous communities.
The mountain region of Shantung consists geologically only of old
formations; folded Archean rocks at the bottom and Paleozoic schist
formations free from folding and metamorphism above. The lowest
rocks are primary gneisses and granites and hornblende schists pene-
trated by pegmatyte and quartz veins. Then follow crystalline schists
and limestones. Granite eruptions (Korea granite) accompanied the
active and intense mountain-making phenomena. The greater portion
of the superincumbent and little disturbed Paleozoic schist massif is
included in the so-called "Sinisch" (Cambrian) formation. In il;,s lower
portion are found coarse conglomerates and sandstones; in the middle
are quartzose sandstones and clay slates interbedded with flat limestones;
in the upper horizons limestones predominate and are characterized by
the oolitic structure.
Unconformable upon these strata follows the Carboniferous, the
Silurian and Devonian being apparently absent. The Carboniferous
begins with limestone; then follow calcareous, occasionally fossiliferous
but usually rather sandy clay slates. With the uppermost members are
found porphyries and porhypritic tuffs of Permian age or younger.
This completes the series of the older formations. The covering consists
of the loess which rests upon all valleys, slopes and low hills.
As is shown or the map published in the "Zeitschrift fiir praktische
Geologic," p. yT, east and west Shantung differ from each other geo-
logically and orographically. Upon the eastern side the Coal Measures
are wanting and the "Sinisch" is not prominently developed; on the
west the strata of the latter formation have a great development and
the Carboniferous is abundantly in evidence. Toward the west the
crystalline rocks do not form prominent features of the landscape; on
the east they predominate. In western Shantung the loess covering is
universal; in eastern Shantung it is rare.
This important dividing line l)etween east and west Shantung is a
■
Review ofRecetit Geological Literature. 323
part of the great boundary line between Liautung and Shantung, which
is also marked by a chain of volcanic eruptives.
In eastern Shantung where gneiss and granite-gneiss prevail there
are evidences of a double folding, one in the normal strike of the
gneisses from north-northwest to south-southeast, and the other parallel
with the strike of the "Sinisch" formation, from west-southwest to east-
northeast.
The mountain region of the west half is composed of a great number
of extensive table-like terraces each of which is raised up on one side
and consists of a crystalline foundation w;ith a capping of "Sinisch"
sediments. The terraces dip in minor folds in a northern direction; but
the lines of fracture have different strikes. There seems to be a ten-
dency toward a radial arrangement with the Tai-shan as a center,
while small breaks running at right angles accompany the radial folds,
and on the northern edge of the mountain region small fractures pro-
duce deep gorges.
There is a close relation between this orographic structure and the
occurrence of the coal beds which are shown on the map already
mentioned. The geological structure which is interpreted as far as is
already known on the map published on page 75 of the Zeitschrift ftir
praktische Geologic, is not yet fully understood. It is probable, how-
ever, that we have here the remnants of a formerly extensive sedi-
mentary series which has been subjected to profound erosion. Its con-
tinuation underneath the younger sediments of the region may probably
be demonstrated by a careful study.
The coal fields alreadv show several beds of most excellent coal of
workable dimensions. They are always found interstratified with lime-
stone and clastic rocks. In the original article are excellent accounts
and profiles of the coal deposits of Po-shan (several seams of from 6
to 8 feet in thickness), Tschung-Kiu (several veins from 4 ^o 6 feet
thick), Wei-hsien (veins 3 to 6 feet thick), I-tschou-fu and I-hsien
probably seven veins up to 5 feet thick).
The first coal field has a considerable but not completely surveyed
area. Its continuation may be looked for toward the east and south
underneath the tuffs which occur in those directions. A careful geo-
logical study would throw important light on this subject.
There are also iron ores in the district of I-tschou-fu which, notwith-
standing their richness, have not yet been worked. Another iron ore
deposit is found east of Tsinan-fu. It is a typical contact deposit and
owes its origin to intrusions of dioryte.
The future of the province of Shantung and Germany's new Chinese
possession depends according to F. v. Richthofen upon the extensive
coal fields. The other metallic riches, of which so many exaggerated
tales are told and which are so graphically portrayed on maps of the
province, are limited to traces of gold in the alluviums and small
amounts of galenite and copper sulphurets in the Archean mountains.
But the future of Kiauchau lies chiefly in its role as a diverging
point for railroads. The coal fields of Shantung will be opened by
324 The American Geologist May. law
them and rendered accessible to the harbors. The coal fields are favor-
ably situated and the deposits are extensive enough to reward develop-
ment and the structure of the coal makes it excellent for use by steam-
ships. The most important point, however, is that in all of southern
and eastern Asia (vide Zeit. f. prakt. Geol. 1894, pp. ^7, 39 and 254; 1897,
P- 389) there is no place where equally good stone coal occurs so near
to a good shipping point. The great and celebrated coal fields of China
lie far inland; Kaiping alone is near the coast, but the voyage thither
is a long one and there is no good harbor. The Mesozoic coals of
Japan and Formosa are much inferior in structure to those of Shantung
and the Tertiary coals of Indian Asia are not to be conipared with them.
The route of the railroads has been officially decided. A road to
Wei-hsien, from there westward toward the northern boundary of the
mountains toward Poschan-hsien and Tsi-nan-fu would make the north-
ern coal fields of the series tributary to the harbor. The construction of
that part which lies in this unusually populous and productive territory
would be easy and inexpensive on account of the extremely low cost
of labor. A further road would have to be constructed in a western
direction toward I-tschou-fu. If the iron ores at this latter point should
prove worthy of exploitation the place would acquire considerable im-
portance. Connection of this place by a road past Yentschoufu to Tsi-
nan-fu would for the present give a very favorable terminal for the
whole system of railroads. *
Until now the coal was almost unavailable. Upon the opening of the
harbor of Kiauchau and the building of the railroad lines mentioned
depends the future of the rich and as yet partly unexplored coal fields of
Shantung. H. V. Winchell.
Water Resources of Indiana and Ohio, By Frank Leverett.
(From the Eighteenth Annual Report, U. S. Geol. Survey, for 1896-97;
Part IV, Hydrography, pp. 419-559, with plates xxxiii-xxxvii, and figures
76, n:)
During the author's extensive explorations of the marginal moraines
and other drift deposits of these states, he has collected, as another branch
of his work, the large amount of exact and well arranged information
which he gives in this memoir concerning the drainage systems, lakes,
underground waters, springs, and water supplies of the cities and villag-
es. One of his maps shows the contour of the district; another, its strat-
ified rock formations; a third, the Pleistocene deposits; and a fourth, the
relation of the drift to the ordinary wells. Complexly looped and inter-
locked moraines, to the number of ten or twelve, traverse Indiana and
Ohio, with large intervening areas of till plains. Older till, covered by
loess, is mapped extending southwest, outside the moraine belts, nearly
to the mouth of the Wabash, and across the Ohio river in the region of
Cincinnati; but each state also has large areas in its southern part beyond
the limits of the drift, excepting the water-borne modified drift of the
river valleys which head within the glaciated area. The memoir will be
of great interest and practical value to the people of these states. It
raises an earnest hope that Mr. Leverett's detailed studies of the drift
there will be as fully published at no distant time. w. u.
Authors' Catalogue, 325
New Developments in Well Boring and Irrigation in Eastern
South Dakota, i8q6. By Nelson Horateo Darton. (From the
Eighteenth An. Rep., U. S. Geol. Survey; Part IV, pp. 561-615, with
plates xxxviii-xlvii, and figures 78-85.)
The present report is supplementary to the paper by Mr, Darton on
the artesian waters of the Dakotas in the last preceding annual report of
this Survey. During the year i8g6, numerous additional wells were
sunk for artesian water, chiefiy to be used for irrigation, in the region of
South Dakota adjoining the Missouri river, from which it is predicted
that good artesian fiows from the Dakota sandstone will be obtained by
deep wells in this valley as far northward as Bismark. Log records of
many of the wells are given. A very remarkable increase of underground
temperature at the moderate depths of the wells (mostly from 500 to
1,500 feet deep) is shown by the temperature of their water. The down-
ward increment of beat is one degree Fahr. for each 17% feet at Fort
Randall, and the whole artesian district has a range from about 20 to 45
feet for each degree, in contrast with an average elsewhere, throughout
the world, of about 50 feet for a degree. The causes of this anomalous
condition, in a region so fclr from any recent volcanic action and undis-
turbed by orogenic processed, are not yet ascertained. w. u.
MONTHLY AUTHORS^ CATALOGUE
OF American Geological Literature,
Arranged Alphabetically*
Agassiz, Louis.
[Various articles on Agassiz and his work.] By A. S. Packard, G.
F. Wright, D. S. Jordan, C. R. Eastman, G. C. Davenport, B. G.
Wilder, and others. (Am. Nat., vol. 32, pp. 147-199, Mch. 1898.)
Bain, H. F.
The Aftonian and Pre-Kansan deposits in southwestern Iowa. [Ab-
stract.] (Am. Geol., vol. 21, pp. 255-262, Apr. 1898.)
Brigham, A. P.
Note on trellised drainage in the Adirondacks. (Am. Geol., vol. 21,
pp. 219-222, pi. 15, Apr. 1898.)
Calvin, Samuel.
The interglacial deposits of northeastern Iowa. [Abstract.] (Am.
Geol., vol. 21, pp. 251-254, Apr. 1898.)
Chalmers, Robert.
The pre-glacial decay of rocks in* eastern Canada. (Am. Jour. Sci.,
ser. 4, vol. 5, pp. 273-282, Apr. 1898.)
*This list includes titles of articles received up to the 20th of the preceding
month, includin^r ireneral ffeolo^y. physiography, paleontology, petrology and
mineralogy.
326 The American Geologist, May, 1886
Dall, W. H.
The future of the Yukon pold fields. (Nat. Geog. Mag., vol. 9,
pp. 1 1 7- 1 20, Apr. 1898.)
Dana, J. D.
Revised text-book of geology. Edited by W. N. Rice. (Pp. ix and
482; American Book Co., New York.)
Darton, N. H.
New developments in well boring and irrigation in eastern South
Dakota, 1896. (U. S. Geol. Survey, i8th Ann. Rept, pt. 4, pp. 561-615,
pis. 38-47, 1897-)
Dawson, J. W.
On the genus Lepidophloios as illustrated from specimens from the
coal formation of Nova Scotia and New Brunswick. (Roy. Soc. Canada,
Trans., ser. 2, vol. 3, sec. 4, pp. 57-78, pis. 1-14, 1897.)
Derby, O. A.
Brazilian evidence on the genesis of the diamond. (Jour. Geol., vol.
6, pp. 121-146, Feb -Mch. 1898.)
Drake, N. F.
A geological reconnaissance of the coal fields of Indian Territory.
(Leland Stanford Junior Liniv. Pub., Contributions to Biology from the
Hopkins Seaside Lab., XIV, 1898. Reprinted from Am. Phil. Soc,
Proc, vol. 36, pp. 326-419, pis. 1-9, Dec. 1897.)
Eastman, C. R.
Agassiz's work on fossil fishes. (Am. Nat., vol. 32, pp. 177-185,
Mch. 1898.)
Emmons, S. F.
Alaska and its mineral resources. (Nat. Geog. Mag., vol. 9, pp.
139-172, Apr. i85fi.)
Farrlngton, O. C.
Datolite from Guanajuato. (Am. Jour. Sci., ser. 4, vol. 5, pp.
285-288, Apr. 189S.)
Foote, H. W. (Penfield, S. L. and)
On clinohedrite, a new mineral from Franklin, N. J. (Am. Jour.
Sci., ser. 4, vol. 5, pp. 289-293, Apr. 1898.)
Frazer, Perslfor.
Archean character of the nuclei of the Antilles. (Am. Geol., vol.
21, pp. 250-251, Apr. 1898.)
Goodrich, H. B.
Recent warpings as shown by drainage peculiarities [in Yukon dis-
trict]. (U. S. Geol. Survey, i8th Ann. Rept., pt. 3, pp. 276-289, pis.
43-44. 1898.)
Goodrich, H. B.
History and condition of the. Yukon gold district to 1897. (U. S.
Geol. Survey, i8th Ann. Rept., pt. 3, pp. 103-133, 1898.)
Guthrie, Ossian.
A view and description of the bed of a prehistoric or glacial lake,
between Summit and Lamont, 111. (Jour. West. Soc. Engineers, vol. 3.
p. 815, Feb. 1898.)
Atiihars' Catalogue, 327
Hidden, W. E., and Pratt, J. H.
• On rhodolite, a new variety of garnet. (Am. Jour. Sci., ser. 4,
vol. 5, pp. 294-296, Apr. 1898.)
Jaggar, T. A., Jr.
An occurrence of acid pcgmatyte in diabase. (Am. Geol., vol. 21,
pp. 203-213, pi. 14, Apr. 1898.)
Keyes, C. R.
The use of local names in geology. (Jour. Geol., vol. 6, pp. 161-170,
Feb.-Mch. 1898.)
Keyes, C. R.
Use of the term Augusta in geology. (Am. Geol., vol. 21, pp.
229-235, Apr. 1898.)
Knowlton, F. H.
Report on a collection of fossil plants from the Yukon river, Alaska,
obtained by Mr. J. E. Spurr and party during the summer of 1896.
(U. S. Geol. Survey, i8th Ann. Rept., pt. 3, pp. 194-196, 1898.)
Leverett, Frank.
Water resources of Indiana and Ohio. (U. S. Geol. Survey, 18th
Ann. Rept, pt. 4, PP. 419-559, pls. zyZ7. 1897)
Leverett, Frank.
The weathered zone (Sangamon) between the lowan loess and Illi-
noian till sheet. (Jour. Geol., vol. 6, pp. 171-181, Feb.-Mch. 1898.)
Leverett, Frank.
The weathered zone (Yarmouth) between the Illinoian and Kansan
till sheet. [Abstract.] (Am. Geol., vol. 21, p. 254, Apr. 1898.)
Leverett, Frank.
The weathered zone (Sangamon) between the lowan loess and Illi-
noian till sheet. [Abstract.] (Am. Geol., vol. 21, pp. 254-255, Apr.
1898.)
Merrill, G. P.
Notes on the geology and natural history of the peninsula of Lower
California. (U. S. Nat. Museum, Rept. for 1895, pp. 969-994, pis. i-io,
1897.)
Penfield, S. L., and Foote, H. W.
On clinohedrite, a new mineral from Franklin, N. J. (Am. Jour.
Sci., ser. 4, vol. 5, pp. 289-293, Apr. 1898.)
Pratt, J. H., (Hidden, W. E., and)
On rhodolite, a new variety of garnet. (Am. Jour. Sci., ser. 4, vol.
5, pp. 294-296, Apr. 1898.)
Preston, H. L.
San Angelo meteorite. (Am. Jour. Sci., ser. 4, vol. 5, pp. 269-272,
Apr. 1898.)
Ries, Heinrich.
Allanite crystals from Mineville, Essex county, N. Y. (N. Y. Acad.
Sci., Trans., vol. 16, pp. 327-329, 1897.)
328 The American Geologist, May, i«8
Ries, Heinrich.
Note on a beryl crystal from New York City. (N. Y. Acad. Sci.,
Trans., vol. i6, i p., 1897.)
Riggs, E. S.
On the skull of Amphictis. (Am. Jour. Sci., ser. 4, vol. 5, pp.
257-259, Apr. 1898.)
Sederholm, J. J.
The geology of the environs of Tammerfors. [Translated from the
guide to the excursions of the Seventh International Congress of Gcol-
Some preglacial soils. [Abstract.] Am. Geol., vol. 21, pp. 262-264,
Smyth, C. H., Jr.
Weathering of alnoite in Manheim, New York. (Geol. Soc. Amer.,
Bull., vol. 9, pp. 257-268, pi. 18, Mch. 28, 1898.)
Spurr, J. E.
Geology of the Yukon gold district, Alaska. With an introductory
chapter on the history and conditon of the district to 1897, by H. B.
Goodrich. (U. S. Geol. Survey, i8th Ann. Rept., pt. 3, pp. 87-392, pis.
32-51, 1898.)
Squier, G. H.
Studies in the driftlcss region of Wisconsin. II. (Jour. Geo!., vol.
6, pp. 182-192, Feb.-Mch. ifi^.)
Turner, H. W.
Description of the Downieville folio. (U. S. Geol. Survey, Geologic
Atlas of the U. S., folio 37, Downieville folio, Calif., 1897.)
Tyrrell, J. B-
The glaciation of north central Canada. (Jour. Geol., voL 6, pp.
147-160, Feb.-Mch. 1898.)
Udden, J. A.
Fucoids or coprolites. (Jour. Geol., vol. 6, pp. 193-198, pis. 7-8,
Feb.-Mch. 1898.)
Udden, J. A.
Some preglacial soils. [Abstract] (Am. Geol., vol. 21, pp. 262-264,
Apr. 1898.)
Upham, Warren.
Drumlins in Glasgow. (Am. Geol., vol. 21, pp. 235-243, Apr. 1898.)
Wadsworth, M. E.
Zirkelite — a question of priority. (Jour. Geol., vol. 6, pp. 199-200,
Feb.-Mch. 1898.)
Wilson, W. J.
Notes on the Pleistocene geology of a few places in the Ottawa
valley. (Ottawa Naturalist, vol. 11, pp. 209-220, Mch. 1898.)
WInchell, N. H.
Some resemblances between the Archean of Minnesota and of Fin-
land. (Am. Geol., vol. 21, pp. 222-229, Apr. 1898.)
Wright, G. F.
Agassiz and the ice age. (Am. Nat., vol. 32, pp. 165-171, Mch. 1898.)
Correspondence, 329
CORRESPONDENCE.
On the Formation of New R*a vines. In the nintH edition
of his *' Principles of Geology" Sir Charles Lyell describes
a ravine near Milledgeville, Georgia, which was excavated in twenty
years to a depth of 55 feet. A part of his account follows:*
"When travelling in Georgia and Alabama, in 1846, I saw in both
those states the commencement of hundreds of valleys in places where
the native forest had been recently removed. One of these newly
formed gulleys or ravines is represented in the annexed wood cut
from a drawing which I made on the spot* * * Twenty years ago,
before the land was cleared, it had no existence; out when the trees of
tie forest were cut down, cracks three feet deep were caused by th<
sun's heat in the clay, and, during the rains, a sudden rush of water
tirough the principal crack deepened it at its lower extremity, from
Krhence the excavating power worked backward, till, in the course of
twenty years, a chasm measuring no less than 55 feet in depth, 300
^ards in length, and varying in width from 20 to 180 feet, was the re-
wlt."
The figure which Lyell publishes shows a great gully with precip-
itous walls. The walls, bottom and surface of the immediately adja-
cent country are represented as bare of trees. A wooded hight is seen
in the distance, and a few scattering trees are shown, but all at a con-
siderable distance from the edge of the ravine. The trees depicted
are those only which have the outline and habit of broad-leaved kinds,
none of them are pines and none are near the edge of the ravine.
Over fifty years have passed since Lyell wrote his description of
this phenomenon. Finding that Lyell's description is still quoted,!
and having some curiosity to know what erosion had been accomplished
since Lyell wrote, it occurred to me a short time ago to write to
Milledgeville for information regarding the present condition of the
ravine. A few days ago I received an excellent description of the
ravine from Mr. J. Harris Ghappell, president of the Georgia Normal
and Industrial College, who, in company with Prof. Beeson, had paid
a visit to the gully on the Saturday before, viz., Jan. 22. Following
is a part of Pres. Chappell's letter: —
"The *?ig Gully,' by which name it is familiarly known, is situated
four and one-half miles from Milledgeville on a high ridge of hills over-
looking the town. The gully is '320 yards long, varies from 80 feet
to 300 feet in width, and is 65 feet deep in its deepest part. From the
main stem springs four zig-zag branches, making of the whole quite
a complex ramification. I should say that the whole wash-out covers
an area of about ten or twelve acres. * * * In some places the
gully is covered with a thick forest growth, mainly pine trees, some of
*The descriptioD stands in the lltb and last edition exactly as in the 9th edition
p. 204. vol. I. p. a38.
tVide Merriirs "Rocks. Rock Weathering and Soils," 1897, p. 386.
330 The American Geologist, May, lawj
them fifty or sixty years old, I should say. In the bottom of the
deepest part we measured a pine tree nearly 4^4 feet in circumference.
* * * At present the gully seems to be at a standstill. I can per-
ceive vio change in it during the six years that I have been Hying in
Milledgeville, though I confess I have not observed very closely.
Through the bottom of the gully, for nearly its full length, runs a tiny
stream not wider than your three fingers, coming from a spring, per-
haps; otherwise the entire excavation is as dry as a bone. Immediately
around the gully is a fringe of woods, the original forest growth, I
suppose; but less than a hundred yards away on all sides are cleared
and cultivated fields."*
In addition to the written account of the present condition of the
ravine Pres. Chappell sent four photographic views which he had
taken on the occasion of his visit to the locality, which supply certain
valuable details. These views show a fringe of trees, principally pines,
bordering the ravine. The tallest of these trees seem to be somewhat
less in hight than the walls of the ravine. In at least two of the
views there are trunks of trees lying on and against the side of the
ravine in such positions as to show that they have fallen from above,
and several others are standing at the very brink of the chasm, with
bared roots from which the earth, into which they once grew, has
fallen away. It is quite evident, from a study of these views in the light
of Lyell's description of the locality, that the trees which now border
the ravine, have grown within the last fifty years, and furnish an ex-
planation to the very natural question, why the wear has not been pro-
portionally as great in the fifty years from 1846 to 1898 as it was in the
twenty years prior to 1846. They show also what is of interest in the
consideration of the influence of forests on soil, that is, the conserving
power of trees to prevent loss and other destructive results to the soil
through erosion. Whether this fringe of trees was planted by the
land owners, or whether the trees were allowed to stand, having sprung
up after the original forest covering was removed, or whether some of
them are a remnant of the original forest, they now stand as a bar-
rier to prevent the too rapid encroachment of the ravine on the adja-
cent fields.
Washington, Pa.^ Feb. 2, r8g8. Edwin Linton.
PERSONAL AND SCIENTIFIC NEWS.
Prof. W. P. Blake, director of the Arizona School of
Mines at Tucson, has been appointed, by the governor, ter-
ritorial geologist of Arizona.
The Societe Geologique de Belgique will celebrate its
25th anniversary at Liege in September. Excursions will be
•Letter dat<Kl Jan. 24tli, 18U8.
Personal and Scientific News, 331
given to interesting geological localities in the vicinity. And
invitations have been sent to the honorary members in the
U. S. and elsewhere to be present and contribute to the in-
terest of the occasion.
The Russian Province of Kursk proves to be one of
the most remarkable areas of magnetic disturbance yet
known. M. Moureaux reports that the differences between
theory and observation are so great that it is not possible to
draw isomagnetic lines, and the magnetic force is as great as
it would be in the immediate vicinity of the magnetic
poles.
It is a remarkable fact that of over 100 finds of
iron meteorites only nine have been seen to fall, while of
over 400 finds of stony meteorites more than one-half have
been seen to fall. Mr. H. L. Preston finds several reasons
for believing that the iron meteorites are merely the crystal-
lized metallic nodules contained in the larger and more con-
spicuous stony meteorites.
Professor Agassiz of Harvard has arrived at San Francis-
co after an absence of some months in the South Seas spent in
studying the formation of the coral islands. It is said that he is
prepared to demonstrate, in opposition to the theories of
Darwin and Dana, that the coral islands are not built up
from the bottom, but are formed by a comparatively thin
crust of coral upon tops of submerged mountains at points
where the ocean is comparatively shallow. In nearly every
instance where borings have been made in the coral the
coral has been found to be shallow. At a few places where
it seems to have great depths Professor Agassiz says that
the material into which deep borings are made is lime of a
former age of the earth.
The American Association for the Advancement of
Science will hold its fiftieth anniversary meeting in Boston
on August 22nd to 27th. Every preparation is being made
to make this meeting of great interest, and it is hoped that
it will be the largest and most enthusiastic meeting yet held.
The members of the local committee are making elaborate
arrangements for entertaining the Association, and a num-
ber of excursions to points of interest will be given. The pres-
ident elect. Prof. F. W. Putnam of Salem, Mass., who has been
permanent secretary of the Association for twenty-five years,
will retain that position until the Boston meeting. The of-
ficers of section E, geology and geography, are: Vice pres-
ident. Prof. H. L. Fairchild, University of Rochester, Roch-
ester, N Y.; Secretary, Mr. Warren Upham, Minnesota
Historical Society, St. Paul, Minn.
Copper in Lake Superior Iron Mines. Two or three
years ago some copper minerals, including the native metal.
332 The American Geologist, May. U9b
were found in small quantities in the Montana mine, at Sou-
dan, Minn., on the Vermilion iron range. (See this journal,
vol. 19, p, 417). Now it is reported that a body of native
copper weighing several tons has been found in the same
mme at a depth of 700 feet from the surface.
Maryland Geological Survey. The Maryland legisla-
ture, in addition to passing the regular appropriations of
820,000 for the state geological survey, has also appropria-
ted to the same organization 2io,000 for topography and
220,000 for the study of the question of road construction in
the state. The latter act calls for the investigation of and
report upon the character and distribution of the natural
road building materials in the several counties and a full
statement regarding the present condition of the roads and
the best means for their improvement, with estimates of
cost of constructing, repairing and maintaining the same.
Such universal approval has been accorded by the people
and press of the state to the geological survey that the acts
passed both houses unanimously. The entire appropriation
has been placed under the direction of Prof. Wm. B. Clark,
of John Hopkins University, the state geologist. {Science.)
Jules Marcou died at his home in Cambridge, Mass., on
April 17th. He was born in France on April 20th, 1824, and
had thus almost completed his 74th year. Prof. Marcou is
well known both in Europe and in America, his adopted
home, from his geological work and writings. His geologi-
cal map of the United States and his early publications on
the geology of the southwestern states, especially on the
Mesozoic, have made him an important factor in the devel-
opment of geological knowledge in the United States. He
was associated with Louis Agassiz,and a few years ago pub-
lished a life of that distinguished naturalist.
Mr. Marcus Baker delivered the annual address before
the Philosophical Society of Washington on April 2nd. The
subject was "A century of geography in the United States."
A. Des Cloizeaiix. A biographical notice of this dis-
tinguished French mineralogist was read by Prof. A. La-
croix before the French Society of Mineralogy aijf*the meet-
ing of Dec. 9, 1897. This notice, accompanied b} a portrait
and a bibliography, appears in the last number/rf^the Bulle-
tin of the Society (vol. 20, no. 8, Dec, 1897). '
Popocatepetl and Orizaba. The various determina-
tions of the hights of these two great Mexican mountains
are given by Mr. A. E. Douglass in *' Appalachia*' for March,
1898. Omitting a number of the least reliable determina-
tions and getting the mean of the others, Mr. Douglass gives
the altitude of Popocatepetl as 17,660 feet with a possible er-
ror of 50 feet, and of Orizaba as 18,240 feet with a possible
error of 160 feet.
THE
AMERICAN GEOLOGIST.
Vol. XXI. JUNE, 1898. No. 6
PALEOLITH AND NEOLITH.
fiy Dr. £. W. Clatpole, Akron, Ohio.
The above terms were introduced into archaeology by Sir
John Lubbock in order to accentuate a distinction previously
felt rather than expressed among the stone implements found
at different prehistoric dwelling-sites in England. The dis-
tinction rests mainly on the single fact that the relics of cer-
tain groups — the palaeolithic — have been shaped entirely by
chipping and never show a trace of rubbing or grinding while
in other groups — the neolithic — ^both methods of fashioning
the tools or weapons have been employed. The presence of a
ground edge or a rubbed face is accordingly a crucial test for
distinguishing the two types.
The value of the terms was at once recognized and the
progress of time and investigation has only rendered them
more useful and important. To some extent also the distinc-
tion has gained a geographical significance and a large area
in northern and northwestern Europe has been delimited over
which it prevails with as great clearness as in England. Out-
side of this region however, for reasons which will appear
later, it cannot always be traced with equal certainty. In fact
it becomes less and less sharp with increasing distance from
the typical center. It is, however, frequently practicable even
in distant places to determine from internal evidence the
palaeolithic nature of certain ''finds" and the neolithic charac-
ter of others.
334 T^^ American Geologist, June. i898
But the fundamental distinction above mentioned, to ex-
press which the terms were invented, has been supplemented
by several other secondary ones of almost equal importance.
Some of these are obvious, others can scarcely be detected
save by an experienced eye. Space will not allow a lengthened
explanation here. A mere mention must suffice. Then the
material of the palaeolith is almost always flint of some kind;
in the neolith other stones are employed; the pattern of the
former is heavier and coarser than that of the latter; the edge
shows little or no secondary chipping; the implement was
often made by a single stroke and is triangular in section ; and
last, though not least, the surface shows a peculiar luster or
"patina" due to age and secondary deposition of silica that is
never seen on newly chipped flints and which it is impossible
to imitate.
By the consideration of these characters or of such of them
as may occur in any specimen it is seldom difficult to deter-
mine whether a collection of flint weapons is of palaeolithic or
of neolithic age. At the same time it must be borne in mind
that implements showing some palaeolithic characters fre-
quently occur among others decidedly neolithic, a circum-
stance which need cause no surprise. On the other hand neo-
lithic implements cannot of course be met with at truly palaeo-
lithic stations. The obvious signification of this is that the
older pattern and material survived into the later time and
were still employed for certain purposes after the newer fash-
ion of grinding had been introduced and other materials than
flint had been adopted.
Slight as the difference may seem between chipping and
grinding it implies nevertheless* an immense advance in art
and an immense lapse of time. The intensely slow progress
of man in those early days can scarcely be realized by any who
have not studied the vast time-intervals of even Quaternary
geology and the stereotyped, non-progressive condition of
savage life. The arts possessed by neolithic man, of which his
palaeolithic predecessor in England was ignorant, implicitly
prove to the student of anthropology the passage of almost
countless years or even centuries during which the race was
groping in the dark along the rough, steep path of progress,
profiting by accidents, led by curiosity and taught by bitter
Paleolith and N eolith, — Clay pole. 335
and costly experience. From the naturally broken flint to the
ground axe of greenstone may seem an easy transition, but
historically it was long and difficult, the outcome of trials and
failures innumerable, of changed environment, of conflict,
struggle and death.
Nor is this surprising to any one who notes the progress
of mankind even at the present time. The history of science
and art reveals a thousand cases in which men have so nar-
rowly missed great discoveries or inventions that on looking
back it seems impossible that they failed to see them. But so
it was, and for another who came after were the renown and
the recompense reserved. The effect of some preconceived
idea, the limited reach of the human faculties, varying but
never great, the difficulty of conceiving anything previously
unknown, all these and other causes act as barriers in the way
of progress which are only overpassed by some unusually
gifted individual or broken down by the steady pressure of the
general advance.
Slower still, without any means of recording and transmit-
ting his experience except by word of mouth, was the advance
of our primitive ancestor and in the single fact that palaeolithic
man was able to spread over all the eastern hemisphere and
perhaps the western also we may read the immense duration of
palaeolithic time. By slow migration from land to land, con-
testing the ground with his great mammalian competitors,
he was able to cover the old world and to leave his tools and
weapons in every land before he succeeded in making the
seemingly small advance that carried him over the barriers
into neolithic time and neolithic conditions.
It may be well in passing to state some of these proofs of
great advance during the lapse of the long ages that are indi-
cated by the profound gap existing between palaeolothic and
neolithic time in Great Britain. Besides the differences in the
weapons and his implements already mentioned we know that
palaeolithic man in England knew nothing of the potter's art,
he had not domesticated any of the brutes, his companions, he
practised no agriculture, built no dwellings, and was probably
quite ignorant of the bow and arrow and of navigation. All
the advantages were possessed by neolithic man on his first
appearance in the region. Add these facts to the former and
336 The American Geologist June, isas
no one can doubt that an immense gap in development exists
between the two.
It was not easy to assign to this vast gap in English pre-
history any sufficient cause or to show why so complete a
break should exist in English archaeology. Geology at
length offered a solution of the problem which apparently
meets every condition and is capable of removing every objec-
tion. Prof. James Geikie in his work on the "Great
Ice Age," by an elaborate and powerful argument,
urged and sustained an explanation which can hardly
fail to commend itself to the scientific student of
archaeology. Prof. Geikie called attention to the fact
that no palaeolithic remains have been found in superficial
deposits in that part of Britain which was covered by the ice
of the last great ice-sheet or in his category the third recur-
rence of glacial conditions (Neudeckian). The few specimens
hitherto reported have been found in caves or similar protected
places. Outside of this region, however, in the eastern and
southern parts of the island palaeolithic remains occur in scores
of spots on the very surface and in the gravels of the river-
valleys. Consideration of this fact led Prof. Geikie to main-
tain that its most rational explanation is that palaeolithic man,
in at least the northern part of England antedated the last
great ice-invasion and that the cause of the absence of his relics
from the glaciated area is simply their destruction by the ice
and the torrents flowing from the glacier. So simple an ex-
planation and one sufficient to meet all the facts of the case
seems to leave nothing to be desired even when estimated
alone, but when all the other circumstances that cluster about
it and confirm it are taken into account its rejection becomes
impossible. Thus Prof. Geikie dwells on the important co-
incidence that what is true of palaeolithic man is equally true of
the remarkable southern fauna that lived in England at the
same time. This fauna, semi-tropical in its character, in-
cluded such animals as the hippopotamus, rhinoceros, south-
ern elephant, hyaena and many other forms indicating a very
warm climate. Their remains also are lacking in the glaciated
area of northern Britain save under conditions that would pro-
tect them from the destructive action of the ice. Now it is
well known that palaeolithic man was a member of the south-
Paleolith and Neolith, — Claypole. j^yj
ern fauna and nothing therefore is more natural than that his
remains and theirs should occur in like conditions and circum-
stances, and it is easy to see the strong confirmation which
the coincidence lends to Prof. Geikie's interpretation.
Obviously this theory in a few words amounts to the prop-
osition that palaeolithic man is in Britain of interglacial age
and that his remains are never found in truly post-glacial
beds. I say **truly" because in a few cases it has not been
possible to determine the exact dates and these must be set
aside as furnishing no evidence in either direction. But wher-
ever the age of the implement-bearing strata can be satisfac-
torily ascertained Prof. Geikie maintains that all those yielding
palaeoliths are of earlier date than the close of the ice-age and
that all of later date invariably furnish implements of neolithic
character.
There is npw no difficulty in explaining the absence of
palaeoliths from the northern portions of the island, while neo-
liths occur in abundance over the whole. The latter are the
remains of the population that came in after the final disap-
pearance of the ice, while the former could only remain in that
part which the ice did not reach. Both are consequently
found in the south and southeast, but palaeoliths occur there
only.
Omitting for lack of space several other confirmatory facts
that might be adduced no one can fail to note how satisfac-
torily Prof. Geikie's theory accounts for the "patina" or aged
appearance upon the surface of a palaeoiith. It is not yet pos-
sible even to surmise with any confidence the relative ages
of interglacial and postglacial deposits, but no geologist can
entertain the smallest doubt that they are separated by an in-
terval, measured in years, of enormous duration.
This is alone a very strong confirmation of the theory and
combined with those previously mentioned cannot fail to com-
mend it to the acceptance of archaeologists, especially when
they reflect that no other explanation of the facts has been put
forward that can in any degree be compared with it for clear-
ness and force.
In British archaeology therefore palaeolithic man and gla-
cial or interglacial man are synonymous terms, while neolithic
338 The American Geologist, June, isas
man is in all cases of postglacial and consequently very much
later date.
It is not at present possible to apply the same distinction
to the human remains foynd in North America. No case has
yet been brought forward in which the tools or weapons of
man have been found in such circumstances as to allow the
belief that they were of interglacial age. Without entering
here into details it will be sufficient to say that the most
ancient and authentic of them make no claim to be of older
date than the gravels of the last great glacial advance. The
stone weapons of Ohio, Minnesota, New Jersey, etc., make no
pretensions to greater antiquity than this. Viewed therefore
according to the manner of British archaeologists and geolo-
gists who accept the theory of Prof. Geikie they are all of post-
glacial and consequently of neolithic date, be their pattern
what it may. Most of them, too, are of so distinctly modern a
type, such as those from California and the New London axe,*
that their neolithic character is obvious. Even the argillyte
implements from New Jersey, probably the oldest yet de-
scribed, cannot claim an antiquity greater than early post-
glacial. The same may be said of the spear-head from New-
comerstown, Ohio.
In view of the above statements it is very desirable to avoid
altogether the use of the terms "palaeolithic" and "palaeolith"
in reference to American prehistoric implements, at least un-
til a good case is made out for an antiquity comparable with
that of the genuine palaeoliths of England. Almost all the
former are essentially and unmistakably neolithic, and that
term alone can characterize them. If, however, any should
feel dissatisfied with a word of so wide a signification and de-
sire one of more restricted meaning I would suggest that
'' pro-neolith'' may be applied to those relics which show by
their association with glacial beds that they are very closely
connected in date with the retreat of the ice, leaving the older
♦If this obvious fact had been borne in mind some of the discussion
on the latter implement at the recent meeting at Toronto (B. A. A. S.)
might have been avoided. One distinguished speaker spent his time
in contesting its palaeolithic nature which no one had even suggested.
It is a ground axe of green slate and its neolithic character was, of
course, assumed without argument by the archaeologists in the section.
Paleolith and Neolith, — Claypole. 339
and more general term to be used in relation to those of yet
later date.*
If, however, archaeologists in America continue the use
of the term "palaeolithic" as descriptive of any of the imple-
ments thus far reported from the United States the word
should be employed in a restricted sense and should refer
merely to the form and nature of the artifact without any
expressed or implied reference to its date. Even then,' how-
ever, confusion is likely to arise and the illicit conclusion may
be drawn that objects to which the same term is applied must
be of corresponding age, — an inference which obviously would
be a logicjal fallacy.
Strong confirmation of the doctrine which assigns all the
hitherto published "palaeolithic (?)" finds of North America
to a much later date than that which is justly claimed for those
of England is found in the comparative recency of their geo-
logical settings. With the exception of certain cases in the*
West no great changes in the physical geography of the coun-
try have occurred, the rivers are in the same valleys, the sea
coast has undergone merely trivial alteration and lakes, the
signs of geographical youth, still thickly dot the glaciated
region. So in England neolithic "finds" occur in similar
conditions.
But on the other hand since the days of ps^laeolithic man
vast changes have taken place in England. Rivers have
changed their courses or have cut down their channels by
hundreds of feet; they have even in some cases been con-
verted into arms of the sea; England has been, once at least,
an integral portion of the European continent, and the whole
drainage system in some parts of the island has been radically
altered. No one can doubt that changes so great in the one
case and so small in the other prove beyond controversy that
the beginning of the palaeolithic era must be separated from
our own by a time interval of which the neolithic era forms
but a comparatively small fraction.
♦The term mesolith will probably be some day required for the
transitional forms which will surely come to light in the progress of
time between the typical palaeoliths and the typical neoliths. Such a
transition must have taken place and it is probable that in regions be-
yond the reach of the ice the more advanced patterns and styles were
in some degree contemporaneous with the earlier forms and may also
he of glacial date.
340 The American Geologist, June, i«9>*
And where can a more rational explanation both of the
changes and of the interval be found than that proposed by
Prof. Geikie, — the relegation of palaeolithic man to a glacial
and of neolithic man to a postglacial date? On this view all
difficulties vanish. The vast antiquity of human remains in
Britain is explicable and the recency, by comparison, of all
yet reported from North America becomes evident and intelli-
gible.
This argument has been before the world now for many
years and considering its cogency it is not a little surprising
to find so distinguished an archaeologist as Sir John Evans,
in his address before the British Association at Toronto in
September last, speaking in a manner betraying not a little
confusion of mind on the subject. It is, of course, not to be
expected that archaeologists should also be geologists, but it is
' absolutely necessary in order to avoid serious error that each
should be familiar with the discoveries of the other when thev
touch upon his own particular province. The study of early
man is the most important meeting-point of the two sciences
and here there should be harmony and mutual understanding.
Yet we find in this address the expression "the Post-glacial or
River -drift period." Now the river-drift is synonymous in Eng-
land, at least in part and perhaps altogether, with the palaeo-
lithic period and consequently on the argument of Prof. Geikie
must be of interglacial age. Indeed some of the very diffi-
culties with which Sir John Evans has met and to whicji he
has called attention in his address instantly disappear on the
adoption of the theory here advocated. He dwells for instance
on the immense duration of palaeolithic time. He says it is
proved "by the thick layer of stalagmite in Kent's cave"; "by
the revolution which took place in the fauna after the latest of
the cave-deposits of the palaeolithic period"; by the remote-
ness of the commencement of the neolithic period and by the
great changes in the surface configuration of the country. All
this is evident, but when we consider what is now known of
the vast length of neolithic time the geologist will find it a diffi-
cult task to crowd both it and palaeolithic time into the post-
glacial era. It is simply impossible. But grant the inter-
glacial date of palaeolithic man and the imaginary difficulties
melt away and time enough can be allowed for all the changes
Paleolith and Neolith. — Claypole, 34 1
referred to above and many others that were unnoticed in the
address.
In another passage Sir John refers to the recent investiga-
tions of Mr. Reid which prove, he says, "that the well known
palaeolithic remains at Hoxne in Suffolk and Hitchin in Hert-
fordshire are of a later date than the Great Chalky Boulder
clay of eastern England". He refers to this as showing the
very recent date, geologically speaking, of these remains. But
it must be recollected that the great chalky boulder clay is
not by any means the last of the glacial deposits of England
and that relics lying on it and therefore of later date may yet
be interglacial. These almost certainly are so.
Furthermore in apparently attempting to establish the
postglacial date of the palaeoliths of England Sir John argues
that some of them have been manufactured from materials that
were brought into the region by the ice and derived from the
boulder clay.
But admitting, as all must do, Sir John's high ability as an
archaeologist, we may be allowed to make the suggestion
that if, as stated in the address, these relics at Hoxne, Bran-
don, etc., lie on the boulder-clay their makers can have had no
trouble in obtaining the materials from the ground beneath
their feet. Had they proved of older date the objection might
have been formidable, but in the circumstances it is merely
irrelevant.
It is too late to argue on this subject as if the glacial era
consisted of a single ice-invasion — one and indivisible — and
as if such an interval as interglacial time did not exist. Un-
certain as its details still are there is no room for doubting the
reality of the recessions and readvances of the ice and the dis-
tinction between "preglacial" and "interglacial," which Sir
John seems to ignore, is of fundamental importance in the
discussion of the problem of early man.
It is difficult to read the address without feeling that it is
in suT)stance an attempt to maintain the postglacial age of all
the yet known remains of man. The expressions "post-glacial
or River-drift period" and "the palaeolithic remains of eastern
England are of a date long posterior to that of the Great
Chalky Boulder clay" can scarcely carry any other meaning.
But as already remarked such an attempt in the present state
342 The American Geologist Jane, uss
of our knowledge must be considered out of date and can only
prove futile. The great length of "neolithic" time, on which
Sir John has rightly laid much stress, utterly precludes suc-
cess. The postglacial evolution of neolithic man to higher
stages of civilization, the emergence of the bronze-culture
and its gradual disappearance before that of iron, the spread
of neolithic art over not merely the eastern but the western
world, assuming its origin in the former, the slowness and
the smallness of every advancing step induce the archaeologist
to claim for neolithic man all that the geologist can allow him
of post-glacial time. And even this will probably prove too
short.
The attempt to explain away or to invalidate the evidence
that has at various times comes to light, especially in recent
years, in favor of a yet greater antiquity for man than that
implied by the term "interglacial" reminds one of the similar
efforts made thirty years ago to refute the evidence of M.
Boucher de Perthes. These Sir John holds up to well merited
derision when he says:
While one class of objectors accounts for the configuration of the
flint implements from the gravels by some unknown chemical agency,
by the violent and continuous gyratory action of water, by fracture re-
sulting from pressure, by rapid cooling when hot or rapid heating when
cold, and even regarded them as aberrant forms of fossil fishes, others
adopted the view that the worked flints had either been introduced into
the beds at a comparatively recent date or that the gravel was a mere
modern alluvium.
Some of the objections that have been urged of late against
the specimens that indicate the existence of man in England
in days even preglacial will in time to come probably seem
as irrelevant, if not as absurd, as those quoted above. The
same may possibly be true of some objections against traces
of early man in the western world.*
Another expression may be noted in the same address
where the distinguished author expresses unwillingness to ac-
*It may readily be admitted that in thousands of cases it is im-
possible to distinguish natural fracture from the handiwork of man.
But setting these aside there is little doubt left after examination of
a large number of specimens. The writer, many years ago, examined
thousands, perhaps hundreds of thousands, of broken flints in the upper
valley of the Thames, but he never found any such collection of chipped
specimens as those shown him by Sir Joseph Prestwich in his collec-
tion from the plateaux of Kent.
Paleolith and Neolith, — Claypole, 343
cept certain implements of palaeolithic type reported from below
the great chalky boulder clay and remarks on "the archaeo-
logical difficulty that man at. two such remote epochs as the
preglacial and the postglacial, even if the term glacial be
limited to the Chalky Boulder clay, should have manufac-
tured implements so identical in character that they cannot be
distinguished apart."
Now waiving the question whether or not these imple-
ments of palaeolithic age can be distinguished, this sentence is
scarcely in accord with the following which occur later in
the same address:
The duration of the palaeolithic period must have extended over
an almost incredible length of time, for valleys some miles in width
and of a depth of from 100 to 150 feet have been eroded since the
deposit of the earliest implement-bearing beds.
Again we read:
We have seen that during the migration of palaeolithic man from his
original home to the west of Europe the forms of the weapons and
tools made from siliceous stones had become stereotyped and that
during the extended period implied by the erosion of the valleys the
modifications in the form of the implements were but slight.
If, then, so little modification occurred in the pattern of the
implements during all the long palaeolithic time there can be
no difficulty arising from the close resemblance of the speci-
mens made before and after the deposition of the chalky boul-
der clay.
All the difficulties, real and imaginary, that can be brought
forward disappear, however, when we accept the conclusion
of Prof. Geikie. Palaeolithic man in England was a member
of the southern mammalian fauna, lived in Britain in the inter-
glacial period perhaps even during the presence of the ice,
disappeared with the fauna to which he belonged and his
place was taken, after an interval, by neolithic man, a member
of another fauna with different arts and methods and doubt-
less coming from a different region.
We need not infer from what has been said that Britain was
occupied by palaeolithic man during all the interglacial pe-
riods though the evidence may some day prove this to have
been the case. Still less can we infer the existence of pre-
glacial man in the same region, though this also awaits proof.
344 Tf^ American Geologist, juue.iaea
and if proved would in no way interfere with Prof. Geikie's
theory.* The immense length of palaeolithic time and the
monotonous sameness of palaeolithic weapons are in perfect
accord with what we must beHeve was an immensely slow
progress from the anthropoid to the man. At the same time
we must bear in mind that much of this monotony is very
likely due to our lack of minute acquaintance with the re-
mains of different periods of palaeolithic time.
What has been said above regarding England is true for
a large but undefined area in northwestern Europe. But out-
side of the glaciated region the wide gap existing in England
between the eras of palaeolithic and neolithic man is not ob-
vious. The probability is that the future will reveal stages
of palaeolithic culture more advanced than those indicated
by the surface discoveries in Britain. The French cavern de-
posits and others may also be quoted in this connection.
Again earlier stages of neolithic culture will very likely come
to light from places yet unsearched and in this way the chasm
existing in the British history of man will probably be filled.
But that this link will be found in Britain or in any country
that was devastated by the ice at its widest extension is un-
likely. The whole fauna of which palaeolithic man was a sin-
gle member disappeared from causes still largely unknown and
a new one took its place with which came, as its most ad-
vanced member, neolithic man.f
*The plateau implements to which attention was called a few years
ago .by Sir Joseph Prestwich in some of his last papers are apparently
the oldest human remains yet known in England, and in spite of all the
objections urged against their authenticity they may yet prove of
preglacial age. The immense erosion of the Wealden district which has
occurred since they were made and buried is alone sufficient proof of
the immense antiquity of these "eoliths" as they have been well termed.
tNote. — Since this paper was written the objections against the
very ancient plateau implements of Kent have been formulated by Mr.
Cunnington in ''Natural Science" and fully answered by Mr. Kennard
(Nov., 1897, and Jan., 1898). On which side lies the greater weight
each reader must decide for himself, but some of the objections strongly
remind one of those which Sir John Evans has so justly criticized in
the passage quoted above.
Anthracite Coal in Arizona, — Blake, 345
ANTHRACITE COAL IN ARIZONA.
By William P. Blake. Tucson, Arizona.
Beds of graphitic anthracite coal occur in the mountains
of the southeastern portion of Arizona. They crop out in
considerable magnitude in the Chiricahua range of mountains
near the bold summit, known as Cochise's Head, south of old
camp Bowie, and about thirty miles from the Southern "Pacific
railroad at Teviston. The chief exposures are near Bridger's
camp, at the head of Wood creek. The beds are there in close
association with shales, sandstones, limestones and massive
conglomerates, in regular strata, resting upon or against a
crystalline gneissic and granitic foundation. The stratified
formations a're believed to be Carboniferous in age and the
coal is presumably a member of the series but its exact rela-
tions stratigraphically have yet to be satisfactorily shown.
The sequence of strata appears to be: conglomerate, lime-
stone, sandstone (quartzyte), black silicious shale, coal, shales,
plutonic dyke, gneiss. The stratified formations attain a
thickness of 2,000 feet or more. The limestones are largely
developed, and are generally blue and but little changed. They
contain encrinites and here and there brachiopod shells, ap-
parently Productus. Other portions of the rock have been
altered to white sub-crystalline beds. There is an abundance
of flint nodules and layers of flint. The strata dip northward
at various angles but generally less than 45°.
The coal beds crop out in a ravine. They have not been
much explored and some of the tunnels in which it is claimed
that three beds were cut have caved in so as not to be acces-
sible, but the great heaps of slaked coal and black dust at
the mouths of such tunnels show that the material was found
in quantity. The only accessible opening showed a thickness
of glossy black graphitic anthracite over twelve feet in thick-
ness. It reminds one of the hard graphitic anthracite of
Rhode Island, but, except in selected specimens, it appears
to carry more ash than the Rhode Island samples and to be
even less available for fuel. It is hard to ignite. The per-
centage of ash is large, as will be seen from the following tabu-
lated results of analyses made by me in the laboratory of the
Arizona School of Mines:
346 The American Geologist June, 18O8
Analysis of Arizona Anthracite.
^0.
Sp. Gr.
Ash.
Combustible
and water.
I
1.49
13.20
86.80
Selected fragments.
2
1.73-1.80
3045
69.55
3
1.76
27.40
72.60
Slaty.
4
1.85
30.00
70.00
((
5
22.04
77.96
Black powder.
No. I, had red ashes; No. 2, white ash; No. 3, white ash,
tinged with red; No. 5, red ash. All the beds afford glossy
black lustrous and shining masses, but generally in curved
layers, and having a graphitic luster, except Nos. i and 5.
No. S is taken out of the mine in a fine Wack powder.
It cannot be claimed that any of this material has much
value as a fuel. It may be found useful in some metallurgical
operations as a deoxidizing agent, or for lining (brasqueing)
crucibles and furnaces.
The presence of such large beds of carbonaceous material is
significant of a great area of Palaeozoic vegetation and of shal-
low seas and coal-forming basis analogous to those of the Coal
Measures. If, as I confidently expect, further investigation
shall show that these graphitic anthracites are metamorphised
coal-beds of Carboniferous age, our present ideas of the west-
ward extension of the flora of that period will require great
modification.
There are many evidences in southern Arizona of shallow
seas in Palaeozoic time, and of great tidal currents, and of ex-
tensive shore-lines. Coarse conglomerates of well-rounded
pebbles of Palaeozoic age abound in the Santa Ritas, in the
Santa Catalinas, in the Babioquirari and other mountain
ranges, and in the low hills of Arivaca, south of Tucson and
near the boundary of Mexico.
Quartzytes — probably Cambrian — are a striking feature
of some of the mountain ranges between Tucson and the gulf
coast of Sonora.
CARBONIFEROUS FORMATIONS OF
SOUTHWESTERN IOWA.
By Chablbs R. Ketes, Des Moinos, Iowa.
For nearly half a century it has been known that the south-
western part of Iowa is occupied by "upper coal measures."
/
Carboniferous of Southwestern Iowa. — Keyes. 347
Singularly enough, during all of this time little more than the
bare fact has been recorded. No succession of strata has been
established ; no subdivisions recognized. Neither has the unity ,
of the sequence been demonstrated. All references to the for-
mation have been in the most general terms. Only local un-
connected sections have been described.
The rocks as a whole were commonly regarded to be far
less important than they really are. Their maximum thick-
ness, for example, was placed at 200 feet, whereas in reality the
measurement is over five times as much.
Although from investigations prosecuted in the neighbor-
ing states of Missouri, Nebraska and Kansas it has been, of
recent years, inferred that the thickness of the "upper coal
measures" was much greater than the estimate given by
White,* his account has long remained the only accessible
information on that part of the state of Iowa. Much uncer-
tainty has thus always existed concerning the geology of the
region. This is well shown by Call's planst of certain deep
wells that were put down at Red Oak and Glenwood. The lat-
ter, for instance, which begins in the Plattsmouth limestone,
is stated to pass through only 150 feet of strata belonging to
the "upper coal measures." In this formation the well ac-
tually penetrates nearly four times the distance mentioned.
Similar statements regarding other deep drill holes were
wholly conjecture.
As the region came to be investigated many new facts
began to furnish substantial data regarding the real extent and
character of the formation. The prevailing notions were
changed very materially. From observations made along the
Missouri river Toddt was led to state that a very noticeable
flexure existed south of the Platte river in Nebraska ; and that
a thickness of the "upper coal measures of at least 350 feet was
demanded by the facts."
After the present geological survey of Iowa was organized
much local information was obtained regarding the southwest-
ern part of the state. For several years, however, pressing
duties elsewhere prevented the general geology of the "upper
♦Geology Iowa, vol. I, p. 298, 1870.
tProc. Iowa Acad. Sci.-, vol. I, pt. ii, p. 60, 1892.
JProc. Iowa Acad, Sci., vol. I, p. 58, 1890.
348 The American Geologist, June, isw
coal measures" from being considered systematically. The
first important reference was in regard to the thickness, the
estimate being placed at 1,200 feet.* The latest suggestion
in this connection is by Norton,t who places the total thickness
of the "lower" and "upper coal measures" combined, at 1,060
feet. In all of these references the plane of separation between
the *'upper" and ''middle," or the "upper" and "lower coal
measures" — the "middle" not being recognized — is understood
to be that selected by White. It is not distinguishable at any
other locality than the one noted by him, and is about 75 feet
below the horizon now adopted for the division plane between
the Des Moines and Missourian series.
As the result of investigations carried on in Missourit the
base of the Bethany limestone was found to be an horizon
that afforded the greatest contrasts of all essential characters.
It properly formed the division between the two principal
series of the region. The Bethany limestone was later cor-
related with the Winterset limestone of Iowa. Since that time
Bain§ has traced the outcrops of the formation all the way
from Guthrie county, in the central part of the state, south-
ward to the typical locality in Missouri.
The fact that the "upper coal measures" of Iowa, which
are now incorporated in great part in the Missourian series,
were never subdivided is due to a number of circumstances.
The vertical extent and importance of the formation was not
recognized; heavy accumulations of drift totally obscured the
rocks; the region occupied by the strata is mainly a water-
shed, and hence no large streams exist to cut down to bed-
rock. In order to decipher the Iowa district it was necessary
to approach it from some other direction than had been hither-
to attempted, — from some locality in which the entire sequence
had been clearly made out. This key was furnished by the
work done in Missouri, and along the Missouri river. There
the full succession of strata had been recently determined, and
some of the formations traced into Iowa.
The subdivisions of the Missourian series, as developed in
♦Iowa Geol. Surv., vol. I, p. 15, 1893.
tibid., vol. VI, p. 333, 1897.
JMissouri Geol. Sur., vol. IV, p. 82, 1894.
§Iowa Geol. Sur., vol. VIII, p. 25, 1898.
Carboniferous of Southwestern Iowa. — Keyes. 349
Missouri and Kansas, and as shown in section along the Mis-
souri river between Kansas City and Omaha, are with their re-
spective thicknesses, as follows :
Feet.
II. Cottonwood limestone 10
10
9
8
7
6
5
4
3
2
I
Wabaunsee shales 500
Forbes limestone* 25
Platte shales 105
Plattsmouth limestone 30
Lawrence shales 265
Plattsburg limestone 35
Parkville shales* 75
lola limestone 30
Thayer shales 50
Bethany limestone 75
Of these the basal number, the Bethany limestone, is
known in the central part of Iowa. Its course has been fol-
lowed through Guthrie, Dallas, Madison, Clarke and Decatur
counties. The shales immediately overlying are also known.
Above them and to the westward limestones and shales crop
out at intervals, but their relations to one another have never
been made out.
On the western boundary of the state, along the Missouri
river, there are known to be exposed the lower two-thirds of
the Wabaunsee shales, the Forbes limestone, the Platte shales,
the Plattsmouth limestone and the upper part of the Lawrence
shales.
The lola limestone, which is perhaps the most important
calcareous member in southeastern Kansas, thins out complete-
ly before reaching the domains of Iowa. The limestones ex-
posed in the belt some distance to the west of the Bethany out-
crops must be referred to the Plattsburg division; the associ-
ated shales beneath to the Thayer and Parkville, and those
above to the Lawrence. These doubtless follow the Platts-
mouth limestone, the Platte shales, and the Forbes limestone,
♦The Forbes limestone is the thick limestone typically exposed in
the top of the bluffs of the Missouri and Nodaway rivers near the
town of Forbes in Holt county, Missouri. It is the highest heavy
limestone in the Missourian series, until the capping Cottonwood is
reached. The Parkville shales are best exposed near the station of
Parkville north of Kansas City. The name is applied to all the beds
lying between the lola and Plattsburg limestones. All the other
names have been used before. The formations and their principal
section will be more fully considered in another place.
350 The American Geologist Jane,i88»
though their exact courses are not yet carefully located. They
are inferred largely from the succession observed a short dis-
tance beyond the boundaries of the state in Missouri.
In southwestern Iowa the general dip of the strata is to-
wards the west. On the Missouri river a lower anticline
brings the Plattsmouth limestone again to view opposite Glen-
wood. All the area east of the river, as far as central Adams
and Taylor counties, is occupied by the Webaunsee shales.
One hundred feet above the base of these shales is the Nodaway
coal seam, that is mined at so many points in Montgomery.
Page, Adams and Taylor counties. The belt 30 to 40 miles
wide, lying to the eastward and reaching to the outcrops of
the Bethany limestone is evidently covered by the other forma-
tions already mentioned, — the lola excepted. Northward
from Kansas City the shales are found to become nuich thin-
ner. Their thickness in central Iowa is very much less than
where exposed along the Missouri river.
Lately a number of deep drill-holes have been put down in
southwestern Iowa. The records of some of these are suffi-
ciently accurate to be of much service in checking the succes-
sion and thickness of the beds composing the Missourian
series.
The Cottonwood limestone and the overlying Oklahoman
series are not believed to be represented within the limits of
Iowa. The nearest known exposures are at Auburn, in Ne-
maha county, Nebraska, and 20 miles from the extreme south-
west Iowa corner. A large part of the Missourian series, in
Iowa, is overlain by Cretaceous rocks, which extend south-
ward in a long tongue to within a few miles of the south boun-
dary line of the state.
According to the most rehable estimate derived from the
Missouri river section, and from a number of deep wells, the
greatest thickness of the Missourian series in Iowa is a little
over 1,000 feet. This is at the extreme southwest corner of
the state. The same figures apply to Missouri, the thickest
point being the extreme northwest corner of that state. The
thickness of the "lower coal measures," or Des Moines series,
in the same locality is about 400 feet.
The Peneplain, — Tarr. 351
THE PENEPLAIN.
By R. S. Tabb, Ithaca, N. Y.
Contents.
Page
Reasons for the paper 351
Definition of a peneplain 852
General acceptance of the i>eneplain :i'>3
Improbability of the peneplain explanation 3.*)8
Lack of evidence of ancient peneplains 356
Evidence against the poneplain theory 361
Alternate hypotheses 364
Conclusion 389
Reasons for the Paper; — Five years ago doubts concern-
ing the value of the evidence of peneplains, which had pre-
viously come to my mind, were distinctly strengthened as the
result of study in the highlands of New Jersey. I was, there-
fore, led to call in question the explanation which even then
was being quite generally accepted. So widespread was the
adoption of the idea that I hesitated to publish these doubts
and decided to give the matter more thought. After two or
three years a paper was prepared stating my objections, and
sent to Prof. W. M, Davis for his consideration. It did not
convince him, nor did his comments upon the paper convince
me that the objections were unsound.
Nevertheless, the failure to convince Prof. Davis induced
me to give the question still more study, with the result that
the longer I have thought upon the matter, and the more ex-
tended my field observations have become, the stronger grows
the conviction that the peneplain explanation is in error.
Therefore, notwithstanding the fact that iiearly all American
geologists have adopted the peneplain explanation, and that
no one has publicly questioned it, I have decided at last to
state my objections in print.*
I have been led to this decision in the belief that it should
be done. Every month, and sometimes oftener, one finds a
statement concerning a new^ly discovered peneplain. They
are being found nearly everywhere. Indeed they are an-
nounced upon the most meagre evidence, and oftentimes with
no statement of evidence whatever. Frequently a new pene-
plain is mentioned as one might state the discovery of a delta
♦I am indebted to Prof. J. C. Branner, Prof. I. C. Russell, Prof.
A. C. Gill and Mr. J. B. Woodworth for kindly reading and com-
menting upon this paper.
352 The American Geologist, June, i898
or a fossil vertebrate ; and not only are single peneplains found
in a given district, but oftentimes several of different ages.
It is perfectly certain that many of the so-called peneplains
have been announced without any semblance of proof. But
it is not against these that I write, for the author of the pene-
plain idea has himself urged more careful study before the
announcement of a 'peneplain, — advice which has not been
generally followed. The literature of geology is becoming
overburdened with peneplains, and the geological history and
geography of the past are often interpreted upon the basis of
these. If any of the peneplains are well founded, their dis-
covery and correct interpretation form an important factor
in geological investigation. On the other hand, if they are
wrongly interpreted, and the entire idea is incorrect, geological
literature is becoming seriously confused, as it has been at
times in the past, when erroneous ideas have prevailed in
large measure as the result of authority. Should this be the
case with the peneplain, the time has long since passed when
the error should have been detected. Believing as firmly as
I do that the peneplain explanation is incorrect, I feel that I
should do wrong to longer delay the publication of my rea-
sons.
At the same time, while I have a firm belief, as stated,
doubts concerning the validity of this position cannot help
arising, for the views that I hold seem opposed to those of
the larger number of leading American geologists. I may
be wrong, and the weight of authority would seem to indicate
that I am. I hope that my paper will call out a discussion
and that if I am wrong, the case will be proved beyond ques-
tion. Even if this is the outcome of this paper, the discussion
may perhaps have a salutary effect in putting a stop to the
reckless announcement of unproved peneplains, and should
lead all geologists to give a more careful study before they put
forward the announcement.
Definition of a Peneplain. — A peneplain is "a nearly
featureless plain" produced by subaerial denudation.* These
are not true plains, but "nearly always possess perceptible
inequalities, amounting frequently to two or three hundred
*Davis: Am. Journ. Sci., 1889, ser. III., vol. XXXVII., p. 430.
The Peneplain, — Tarr, 353
feet."* This levelness is in spite of irregularity of rock
"structure."! No extensive peneplains are known to exist
at the present time in any part of the earth, but many are
inferred from the crest lines of old mountains, which are be-
lieved to represent the remnants of dissected ancient pene-
plains, produced during some previous geographic cycle. It
is this conception of a peneplain which is discussed here, and
for typical illustrations the peneplains of New England and
New Jersey are selected, because they have been most fully
studied and discussed, and rest upon the firmest basis.
General Acceptance of the Peneplain Idea. — Few new
theories have been so rapidly and uniformly accepted in this
country as that of the peneplain suggested by Prof. W. M.
Davis about nine years ago. \ Indeed its acceptance has be-
come so universal and indiscriminate that the author of the
explanation has found it necessary to caution his followers
against rashness of conclusion, and to call for a more careful
study of specific cases.§ As in the case of most new ideas
the followers have gone beyond the originator, and it is per-
fectly apparent that a great many of the so-called peneplains
which have been described rest upon very much less secure
basis than the types to which Prof. Davis has called especial
attention. In this country many have evidently accepted
Prof. Davis' explanation without question, and applied it to
very doubtful cases. j|
Improbability of the Peneplain Explanatiofi . — So far there
has been no extensive peneplain of recent date, nor even an
approximation to one, found on the earth's surface in regions
of folded rocks. Yet if we may judge from the evidence ad-
duced by the modern workers in physiographic geology, pene-
plains have been produced again and again at various times
in the past. That is to say, during some past times there
♦Davis: BuH Gcol. Soc. Amer., 1896, vol. VII., p. 393.
tDavis: Am. Journ. Sci., 1889, ser. III., vol. XXXVIL, p. 430;
Proc. Boston Soc. Nat. Hist., 1889, vol. XXIV., p. 373; Nat. Geog.
Monog., 1896, vol. I., p. 271.
J Am. Journ. Sci., 1889, ser. IV., vol. XXXVIL, p. 430.
§ Bull. Geol. Soc. Amer., 1896, vol. VII., pp. 377-398.
1;I feel free to speak upon this point, since I have been guilty
of the same error, having described as a peneplain in Texas some-
thing which may perhaps be a plain of marine denudation. See
Proc. Phila. Acad. Nat. Sci., 1893, p, 317.
354 ' The American Geologist, Jane, ii«8
have been periods of sufficient land rest to allow mountain
masses to be worn down to very near the base level. This
means relative quiet, or fluctuations about an average level,
for a sufficiently long period of time to admit of the slow
process of approximate base leveling. Therefore, in accept-
ing the peneplain theory, we need, as a fundamental assump-
tion, to believe that during a part of the remote past, the con-
ditions have been different from those that have prevailed in
any portion of the known earth during the present and imme-
diate past.
Few American geologists will be found who will deny the
possibility of base leveling, — that, given time, the surface of
the land will be leveled to the condition of a peneplain. Such
a principle may readily be given a place in an ideal cycle of
land development but there should be some real evidence
before applying the ideal to the interpretation of existing con-
ditions.
The wearing down of elevated mountains to those of mod-
erate relief may be granted, and the theoretical possibility of
their further reduction to the base level may also be accepted.
But when the stage of maturity has been reached, the further
process of down-wearing must become progressively slower.
This will be so, partly because decreased relief of land dimin-
ishes the power of the agents of denudation, and partly in
a more indirect manner, by furnishing to the undulating sur-
face a capping of residual soil which protects the rock from
the action of many of the agents of weathering. It seems
impossible to state just what would be the curve of rapidity
of denudation with diminishing altitude, but it is evident that
the rate diminishes so rapidly with decreasing slope, that,
before the condition of the peneplain is really reached, the
rate of down wearing must become exceedingly slow.
In the summer of 1897 I spent a month among the moun-
tains of central Maine, the larger part of the time being in the
Penobscot drainage area. When I started upon the ascent of
^It. Katahdin, there had been five days of very heavy rain,
so that the mountain trails were transformed to brooks, and
the East Branth of the Penobscot had risen a number of feet,
almost to the level of the spring freshets. The trail up the
mountain led across this river, which was fed by mountain
The Peneplain, — Tarr, 355
torrents, having their source from 2,000 to 5,000 feet above
fhe main river. The Penobscot was not even clouded with
sediment. The mountain torrents and the smaller branches
from the primeval forests were doing little more work of
transportation than that of carrying their slight load of dis-
solved mineral. This period represents one of the three or
four annual freshets when the greatest amount of work of de-
struction is done in the drainage area. But, even at such a
time, the work done was marvelously slight in amount. Dur-
ing the remainder of the year, still less is done. Yet this is
a mountainous region where denudation is certainly much
more active than it would be in a more reduced area approach-
ing the peneplain stage. At this rate how long will it take to
reduce Mt. Katahdin, from its elevation of about a mile, and
its neighbors, only slightly lower, to the condition of a pene-
plain ?
During all the time necessary to reduce a hilly country to
the condition of a "nearly featureless plain," time to be
counted in immense ages, the land must remain nearly at one
level ; for if it is elevated, the task is increased, and the time
needed for reduction correspondingly lengthened; if much
depressed a part of the lowered region is submerged, and the
work checked, or perhaps even lengthened by the deposit of a
load of sediment upon it, which must be removed before fur-
ther lowering can be accomplished.
The belief in the reduction of a country to the condition
of a peneplain rests upon an assumption very difficult to real-
ize, but which could be granted if the peneplain were proved to
represent a real condition, and this to be the sole explanation.
This assumption of immense periods of time, with relative
land quiet during certain periods of the earth's history, con-
flicts so markedly with what we know of the present and past,
both immediate and remote, that its acceptance means no less
than the belief that at some periods of the past the conditions
have been different from those of the present, and from those
of that portion of the past whose history has been worked out
by purely stratigraphic methods.
Add to this the fact that the extensive peneplains so far dis-
covered are all of the past, and that no part of the earth re-
veals even an approximation to this supposed condition, and
362 The American Geologist, June, i898
one may feel distinctly skeptical; and when this is argued in
spite of the fact that the land is apparently so unstable, one
may well demand that evidence of the best and most satisfac-
tory kind be adduced. The instability of the land, both present
and past, combined with the slowness of denudation even in
distinctly upland regions, and its rapidly increasing slowness
as these are lowered, appear to be evidence against the pene-
plain of such strength that only the most convincing proof that
such plains have really existed can offset it.
Then the very irregularity of tHe surface, let us say of
New England and the neighboring regions, argues against the
peneplain so strongly that here •also convincing proof of the
peneplain should be necessary to offset this. The type feature
of New England is not the peneplain remnant, but the low
mountain. It is only in the lower portions, not far removed
from the sea, that there is any semblance of a dissected pene-
plain. Much more than one-half of New England is dis-
tinctly mountainous and irregular. There are single isolated
peaks, isolated groups of peaks, and entire mountain masses.
•Where will one go in the White mountains to find evidence of
a former plain? or where in northwestern Massachusetts and
Vermont, or in the Adirondacks? Last summer I stood upon
the crests of several of the higher peaks of Maine and looked
in vain for any series of peaks that even to the eye appeared
uniform in level. The region is essentially that of mature
mountains somewhat roughened by recent elevation. Lesj
markedly is the same true of the coast of Maine. Mt. Desert,
Blue hill and many other peaks in that neighborhood contrast
very strongly with their neighbors, some of which are half
as high, others a quarter, and still others mere low hills or
even reefs in the sea. A model of New England large enough
to really show the differences in elevation would reveal a very
irregular surface, not merely where incised by valleys cut dur-
ing the Tertiary uplift, but among those uplands which should
represent the ancient peneplain. Unless the evidence of the
New England peneplain is of the very strongest kind, this
irregularity would seem to stand forth in positive testimony
against the belief in the former reduction of this region to any-
thing approaching a plain. To attempt to account for this by
exceptional conditions seems an admission of a weakness in
the explanation.
The Peneplain, — Tarr. 363
So-called monadnocks appeal to me as proof against the
peneplain theory. Grant for the moment the destruction of a
mountainous surface to the condition of a plain under subaerial
denudation, and this reduction must certainly call for a very
great lapse of time. During such reduction it may be ad-
mitted that the soft rock will be much more reduced than the
harder ones, and that the latter may stand well above the
general level as residuals ; but are the monadnock rocks essen-
tially harder than the other hilltop rocks of the neighborhood?
I know of no evidence that has been made public that Mts.
Monadnock and Washington are made of harder rock than
many of the much lower hills within a radius of twenty miles
from them. I know of no proof that they are more resistant
than the Blue hills near Boston, nor that these are harder than
the lower granite hills of Essex county, Massachusetts, a few
miles away. Is the rock of Mt. Washington more durable
than that of Essex county, Massachusetts, or the rock of Mt.
Katahdin or Blue hill, in Maine, harder than that of scores
of lower hills not far away? I believe that I am correct in
saying that there are no very distinct diflferences between the
rocks of the monadnocks and the lower hills, in point of dura-
bility, while there is a difference in elevation of more than a
mile, and, even in short distances, of 2,000 or 3,000 feet. In
some of these cases it is certain that the rocks of low and high
hills are not .markedly different.
Without the existence of very notable differences in power
of resistance, is it probable that a hill would stand several
thousand feet above a plain which stretched all around its base,
and which has been reduced to this condition by the slow
process of subaerial denudation? After the region surround-
ing the monadnock had been reduced to the condition of a low,
undulating hilly country, all the time required to plane it down
to the condition of a peneplain has not been able to reduce the
elevation of the higher, and hence more rapidly destroyed part,
to approximately the same level !
It must be confessed that this opposing evidence is based
purely upon my own ability to conceive of the processes in-
volved. In so far as this power of conception is strong or
weak, this part of the argument is good or bad. I would put
it forward with more hesitation if there did not appear to be
364 The American Geologist. June, i(t98
good evidence that the rate of denudation is exceedingly slow
in a forest covered country, and that the land is and has been
far from stable, when long periods of time have been involved.
Alternate Hypotheses.— T-wo hypotheses have been sug-
gested to explain the facts considered above: (i) that of
marine denudation; (2) that of subaerial denudation. Al-
though American geologists in general consider marine de-
nudation possible on!y in rather restricted areas, this hypothe-
sis is certainly not an improbability. So, also, subaerial de-
nudation, if continued long enough, with land level maintained
somewhat uniformly throughout, would undoubtedly reduce
any area to a level condition, though the places most likely to
be so reduced are those near the sea, or those in which the
rocks are soft, or the elevation slight. The possibility of these
two causes for reduction is not questioned, although the prob-
ability of general reduction by such causes is called in ques-
tion. This doubt is still further strengthened by the belief that
the evidence of ancient peneplains, upon which the entire ar-
gument of former base-leveling is founded, is far from con-
vincing.
Summarizing this evidence it seems that the ancient plain
is constructed upon the basis of the existence of moderately
uniform hill crests, whose total area is not more than 10 to 25
per cent of the entire area. Even among these, the hill tops
reach to considerably different elevations. Of the remain-
ing 75 to 90 per cent the greater part is sunk below this upland
level. The hill tops are mainly of hard rock, while the valleys
are mainly located in the areas of less resistant beds, and the
streams are, in general, in quite close accord with the rock
structure. There are, moreover, numerous localized eleva-
tions, called monadnocks, reaching well above the upland
level; and, in the western and northern portions of New
England, at no very great distance from the coast, the region
is elevated and very irregular and mountainous, as for instance
in Maine, the White mountains, Green mountains. Berkshire
hills and Adirondacks. These greater "'" — '- — -' * ---
respond with marked differences in re
vocates of the peneplain admit past irn
monadnocks rising above the ancier
also admit present irregularity in a n
The Peneplain, — Tarr. 365
plain it by one of three conditions, either post-peneplain de-
nudation, or ancient irregularities upon this peneplain surface,
or differential elevation of the peneplain since its formation.
In the present condition of New England and New Jersey,
I am unable to see any evidence that the region was ever re-
duced further than the condition of full maturity of topogra-
phy, — that is, a region of hills and valleys of considerable vari-
ety, and, away from the sea shore, of rounded but considerably
elevated mountains. That this mature mountain region has
been subjected to later elevation, which has rejuvenated the
rivers, seems certain. According to this, the present New
England topography is mainly one of reduced mountains,
lowered to the stage of full maturity, then elevated and* made
more rugged. By this explanation it is held that the region
was never reduced to the peneplain stage, but has always been,
as it still is, a mountainous section, though once less mountain-
ous than now, because of the recent uplift.
So far as I can see, the facts in the fielci are in fuller har-
mony with this explanation than with that of the peneplain.
The present marked irregularity of surface is explained with-
out other assumption than that certain places were formerly,
as now, either high or low, as they would naturally be in a re-
gion of mature mountains. It does away with the necessity
of assuming long periods of time during which the land re-
mained at approximately one level. To reduce a mountainous
region to the stage of maturity is an easy task compared with
the reduction of a mature mountain region to a peneplain. It
would be impossible to state what the ratio of time is, but it
is certain that to lower a mature mountain to a peneplain must
take many times as long as to reduce a mountainous area to
that of maturity. Moreover, much more variation in elevation
is possible under the explanation here proposed than under
that of the peneplain. While the mountains were being low-
ered to the stage of maturity, there might be very much fluc-
tuation of level without marked interference with the contin-
uation of the process of production of mature forms. Besides
this, while there are no existing peneplains, there are at pres-
ent many regions of reduced mountains approaching the stage
of maturity — witness the very regions under consideration.
366 The American Geologist. juoe.isw
It may be argued that the number of hills reaching to a
moderately uniform elevation which are found in southeastern
New England, and in New Jersey, cannot be accounted for by
this hypothesis. When we take into account their present ir-
regularity of surface, this asserted uniformity does not appear
so marked. Upon my mind the impression of irregularity is
produced much more strongly than that of regularity, par-
ticularly when the monadnocks and higher irregularities of
the northern and western part of New England are included.
It is true that near the coast the uniformity is more marked
than in the interior; but here, of course, the mountains would
have been more lowered than in the interior, and, in the coastal
region, there may well have been an approach toward the
condition of a local peneplain. Yet, when we consider such
isolated elevations as that of the Blue hills, near Boston, and
the ruggedness of the Maine coast and of Nova Scotia, as
well as of the region . farther north in Labrador, even here,
where the peneplain condition should" have been most fully
reached, the regularity of level can be urged only when numer-
ous local exceptions are eliminated.
However, it is necessary, if this proposed hypothesis is to
be accepted, to account for even the measure of uniformity that
exists, even though it is really less marked than some believe.
In the reduction of a mountain mass toward base level, long
before the peneplain stage is reached it seems certain that there
would be a uniformity of level among the mountain crests fully
as marked as that now found in New England, and that this
uniformity would naturally be greater near the sea, where
development would have been most advanced.
Given a mountain region of marked irregularity, such as
New England must have been during the Paleozoic, the rocks
from place to place varied greatly in hardness and in attitude,
while the peaks in different sections
different altitudes. If we should sel
boring peaks or ridges of approx
attitude, and altitude, it would fol
exposed to the same climatic cone
toward base level would be continu
as a general proposition, though,
any selected place, be accidents of
The Peneplain, — Tarr, 367
terfere. This rate of denudation among these neighbors
would at first be rapid; for, in the inception of the work, the
elevation was great, the slope steep, and the rocks were ex-
posed to strong winds and powerful frost action, while they
were not protected by trees. The rate of downwearing, as
we see upon similar peaks in the higher mountains of the
present, would have been much more rapid than at any later
stage, decreasing in rapidity as they were lowered;
though still being worn down rapidly until the zone of the
timber line was reached. Then conditions of an entirely new
kind would have been introduced, and, from that line down-
ward, the rate of denudation of the peaks would greatly de-
crease, partly because of the lessened slope, but chiefly be-
cause of the protection of the forest, which holds the disinte-
grated pieces in place, and helps make a protection of residual
soil. As the forest covering became greater, and the slope
less, the soil covering would become deeper, and the rocks
more and more protected, until denudation had become ex-
ceedingly slow. These two peaks, starting at the same level,
having the same kind of rock throughout, and exposed to the
same conditions, would reach this stage of development
(namely their crests at approximately the timber line), at about
the same time; and, as their crests sank lower below this
level, the peaks would still stand at about the same elevation.
In an extensive mountainous region there may have been a
number of such cases.
But there would not be many such peaks of the same
hight or so similar that they would be reduced at nearly the
same rate. Some would be of easily denuded rock, and, in
time, these would be very much lowered, while the harder
ones stood well above the base level. There would at first
be very marked ruggedness, partly the result of difference in
original elevation, and partly the result of the effects of sub-
aerial denudation upon the much elevated and differentiated
surfaces. One peak, perhaps of slightly less durable rock
than a neighbor, would be lowered at a very much more rapid
rate than its neighbor. But there would come a time when
this difference in rapidity would be very much diminished,
even if the rock of the two peaks were quite different. This
time would come when the zone of trees was reached; and
368 The American Geologist. June, it**
the difference in rate of downwearing would even more rapidly
diminish as soon as a soil covering became possible. In the
meantime, a higher or more durable neighbor might still be
sinking more rapidly, and, in time, might almost catch up with
a more favorably situated and lower peak. The curves of the
rate of denudation in the two cases would approach and
finally almost coincide; and, unless the rock differences were
marked, the two peaks would proceed to be lowered at about
the same rate. If the rock differences were very marked, there
would be no exact approach; but, according to this view of
the method of denudation, even though there was originally a
marked difference in altitude, all peaks whose rocks were ap-
proximately the same in power of resistance would in time
approach each other in altitude, the one originally higher
catching up with the other whose rate of lowering was becom-
ing rapidly diminished because of decreased elevation. It
must be granted that in such a mountainous country as that
of New England down below the surface there are extensive
beds of rock of approximately the same hardness. That this
is so is proved by the abundance of durable gneiss and granite
in most low mountainous areas, as for instance in New Eng-
land and New Jersey.
By this there would be a beveling of the hill tops, the
highest area of beveling being that part of the tree zone in
which, because of lessened slope, the rock was protected by
trees and by a residual soil blanket. Down to this zone de-
nudation would be relatively rapid, below it much slower, and
increasingly slower as the beveling continued still further. In
a mature mountain region so developed there would be some
peaks not yet lowered to this area, and there would be great val-
leys depressed below it. But would it be incorrect to assume
that in a given area where most lowered, from lo to 25 per
cent of the reduced mountain tops would probably have
reached a fair uniformity of level? This beveling of the hill
tops would be very much further advanced near the coast
than in the interior, thus coinciding with the conditions found
in New England.
According to this view, by the time maturity of topograph-
ic form has been reached, there will be a beveling of hill tops
where the harder gneissic and granitic rock exists, the stream
The PeTieplain, — Tarr. 369
valleys standing near the base level and hills of softer strata
standing at levels still lower than those in which the rock is
harder. Areas originally distinctly higher or harder than
usual, or more unfavorably situated, may be less lowered and
more irregular than the surrounding region, though still en-
gaged in an approach to this lower level. A well matured
surface would then present three intergrading stages in differ-
ent places and under different conditions, (i) Local base
levels in the valleys; (2) general well matured topography
with many hills reaching to approximately the same general
level, but with some distinct and many indistinct "monad-
nocks"; (3) exceptional and localized early maturity, found
particularly in the interior. The further the topographic de-
velopment had gone toward old age, the greater would be the
extent of the first two areas. Can any evidence be adduced to
show that New England has ever advanced further in de-
velopment than this stage?
Granting such a reduction, with many hills of hard rock
standing at a moderately regular level if an elevation succeeds,
while the valleys will be deepened and the hills lowered, the
rate of lowering of the hills will be so nearly uniform, since
the climate and rock are so nearly alike, that the measure of
uniformity of upland level will in part be maintained.
Canclusion — The questions raised in this paper are not
against the great importance of subaerial denudation, which
few American geologists are inclined to underestimate. The
stamp of the genius of Powell, Gilbert, Davis and others is too
plainly marked upon the minds of American geologists for any
underestimation of the importance of this. The question I
raise is whether far too much importance has not been as-
signed to this great work. The facts and assumptions upon
which the peneplain theory is based are also called in ques-
tion,, and an attempt is made to show that all the phenomena
believed to indicate the existence of peneplains in New Eng-
land and New Jersey can best be explained without assuming
the reduction of a high mountainous country to the condition
of old age, a condition now nowhere found on the earth.
The alternate hypothesis of beveling down to mature form
is advanced. This hypothesis requires no long periods of rel-
ative quiet, and no assumptions to explain the irregularities of
364 The American Geologist, June, ib98
good evidence that the rate of denudation is exceedingly slow
in a forest covered country, and that the land is and has been
far from stable, when long periods of time have been involved.
Alter7iate Hypotheses. — Two hypotheses have been sug-
gested to explain the facts considered above: (i) that of
marine denudation; (2) that of subaerial denudation. Al-
though American geologists in general consider marine de-
nudation possible only in rather restricted areas, this hypothe-
sis is certainly not an improbability. So, also, subaerial de-
nudation, if continued long enough, with land level maintained
somewhat uniformly throughout, would undoubtedly reduce
any area to a level condition, though the places most likely to
be so reduced are those near the sea, or those in which the
rocks are soft, or the elevation slight. The possibility of these
two causes for reduction is not questioned, although the prob-
ability of general reduction by such causes is called in ques-
tion. This doubt is still further strengthened by the belief that
the evidence of ancient peneplains, upon which the entire ar-
gument of former base-leveling is founded, is far from con-
vincing.
Summarizing this evidence it seems that the ancient plain
is constructed upon the basis of the existence of moderately
uniform hill crests, whose total area is not more than 10 to 25
per cent of the entire area. Even among these, the hill tops
reach to considerably different elevations. Of the remain-
ing 75 to 90 per cent the greater part is sunk below this upland
level. The hill tops are mainly of hard rock, while the valleys
are mainly located in the areas of less resistant beds, and the
streams are, in general, in quite close accord with the rock
structure. There are, moreover, numerous localized eleva-
tions, called monadnocks, reaching well above the upland
level; and, in the western and northern portions of New
England, at no very great distance from the coast, the region
is elevated and very irregular and mountainous, as for instance
in Maine, the White mountains, Green mountains, Berkshire
hills and Adirondacks. These greater elevations do not cor-
respond with marked differences in rock structure. The ad-
vocates of the peneplain admit past irregularity, in the form of
monadnocks rising above the ancient peneplain, and they
also admit present irregularity in a marked degree, but ex-
The Peneplai7i, — Tarr. 365
plain it by one of three conditions, either post-peneplain de-
nudation, or ancient irregularities upon this peneplain surface,
or differential elevation of the peneplain since its formation.
In the present condition of New England and New Jersey,
I am unable to see any evidence that the region was ever re-
duced further than the condition of full maturity of topogra-
phy, — that is, a region of hills and valleys of considerable vari-
ety, and, away from the sea shore, of rounded but considerably
elevated mountains. That this mature mountain region has
been subjected to later elevation, which has rejuvenated the
rivers, seems certain. According to this, the present New
England topography is mainly one of reduced mountains,
lowered to the stage of full maturity, then elevated and* made
more rugged. By this explanation it is held that the region
was never reduced to the peneplain stage, but has always been,
as it still is, a mountainous section, though once less mountain-
ous than now, because of the recent uplift.
So far as I can see, the facts in the field are in fuller har-
mony with this explanation than with that of the peneplain.
The present marked irregularity of surface is explained with-
out other assumption than that certain places were formerly,
as now, either high or low, as they would naturally be in a re-
gion of mature mountains. It does away with the necessity
of assuming long periods of time during which the land re-
mained at approximately one level. To reduce a mountainous
region to the stage of maturity is an easy task compared with
the reduction of a mature mountain region to a peneplain. It
would be impossible to state what the ratio of time is, but it
is certain that to lower a mature mountain to a peneplain must
take many times as long as to reduce a mountainous area to
that of maturity. Moreover, much more variation in elevation
is possible under the explanation here proposed than under
that of the peneplain. While the mountains were being low-
ered to the stage of maturity, there might be very much fluc-
tuation of level without marked interference with the contin-
uation of the process of production of mature forms. Besides
this, while there are no existing peneplains, there are at pres-
ent many regions of reduced mountains approaching the stage
of maturity — witness the very regions under consideration.
366 The America?i Geologist, Ju«e, isw
It may be argued that the number of hills reaching to a
moderately uniform elevation which are found in southeastern
New England, and in New Jersey, cannot be accounted for by
this hypothesis. When we take into account their present ir-
regularity of surface, this asserted uniformity does not appear
so marked. Upon my mhid the impression of irregularity is
produced much more strongly than that of regularity, par-
ticularly when the monadnocks and higher irregularities of
the northern and western part of New England are included.
It is true that near the coast the uniformity is more marked
than in the interior; but here, of course, the mountains would
have been more lowered than in the interior, and, in the coastal
region, there may well have been an approach toward the
condition of a local peneplain. Yet, when we consider such
isolated elevations as that of the Blue hills, near Boston, and
the ruggedness of the Maine coast and of Nova Scotia, as
well as of the region. farther north in Labrador, even here,
where the peneplain condition should" have been most fully
reached, the regularity of level can be urged only when numer-
ous local exceptions are eliminated.
However, it is necessary, if this proposed hypothesis is to
be accepted, to account for even the measure of uniformity that
exists, even though it is really less marked than some believe.
In the reduction of a mountain mass toward base level, long
before the peneplain stage is reached it seems certain that there
would be a uniformity of level among the mountain crests fully
as marked as that now found in New England, and that this
uniformity would naturally be greater near the sea, where
development would have been most advanced.
Given a mountain region of marked irregularity, such as
New England must have been during the Paleozoic, the rocks
from place to place varied greatly in hardness and in attitude,
while the peaks in different sections naturally reached to very
different altitudes. If we should select from these, two neigh-
boring peaks or ridges of approximately the same texture
attitude, and altitude, it would follow that, since they were
exposed to the same climatic conditions, their downwearing
toward base level would be continued at about the same rate.
as a general proposition, though, of course, there might, in
any selected place, be accidents of variations which would in-
The Peneplain, — Tarr, 367
terfere. This rate of denudation among these neighbors
would at first be rapid; for, in the inception of the work, the
elevation was great, the slope steep, and the rocks were ex-
posed to strong winds and powerful frost action, while they
were not protected by trees. The rate of downwearing, as
we see upon similar peaks in the higher mountains of the
present, would have been much more rapid than at any later
stage, decreasing in rapidity as they were lowered;
though still being worn down rapidly until the zone of the
timber line was reached. Then conditions of an entirely new
kind would have been introduced, and, from that line down-
ward, the rate of denudation of the peaks would greatly de-
crease, partly because of the lessened slope, but chiefly be-
cause of the protection of the forest, which holds the disinte-
grated pieces in place, and helps make a protection of residual
soil. As the forest covering became greater, and the slope
less, the soil covering would become deeper, and the rocks
more and more protected, until denudation had become ex-
ceedingly slow. These two peaks, starting at the same level,
having the same kind of rock throughout, and exposed to the
same conditions, would reach this stage of development
(namely their crests at approximately the timber line), at about
the same time; and, as their crests sank lower below this
level, the peaks would still stand at about the same elevation.
In an extensive mountainous region there may have been a
number of such cases.
But there would not be many such peaks of the same
hight or so similar that they would be reduced at nearly the
same rate. Some would be of easily denuded rock, and, in
time, these would be very much lowered, while the harder
ones stood well above the base level. There would at first
be very marked ruggedness, partly the result of difference in
original elevation, and partly the result of the effects of sub-
aerial denudation upon the much elevated and differentiated
surfaces. One peak, perhaps of slightly less durable rock
than a neighbor, would be lowered at a very much more rapid
rate than its neighbor. But there would come a time when
this difference in rapidity would be very much diminished,
even if the rock of the two peaks were quite different. This
time would come when the zone of trees was reached; and
368 The American Geologist. June, ibft<
the difference in rate of downwearing would even more rapidly
diminish as soon as a soil covering became possible. In the
meantime, a higher or more durable neighbor might still be
sinking more rapidly, and, in time, might almost catch up with
a more favorably situated and lower peak. The curves of the
rate of denudation in the two cases would approach and
finally almost coincide; and, unless the rock differences were
marked, the two peaks would proceed to be lowered at about
the same rate. If the rock differences were very marked, there
would be no exact approach; but, according to this view of
the method of denudation, even though there was originally a
marked difference in altitude, all peaks whose rocks were ap-
proximately the same in power of resistance would in time
approach each other in altitude, the one originally higher
catching up with the other whose rate of lowering was becom-
ing rapidly diminished because of decreased elevation. It
must be granted that in such a mountainous country as that
of New England down below the surface there are extensive
beds of rock of approximately the same hardness. That this
is so is proved by the abundance of durable gneiss and granite
in most low mountainous areas, as for instance in New Eng-
land and New Jersey.
By this there would be a beveling of the hill tops, the
highest area of beveling being that part of the tree zone in
which, because of lessened slope, the rock was protected by
trees and by a residual soil blanket. Down to this zone de-
nudation would be relatively rapid, below it much slower, and
increasingly slower as the beveling continued still further. In
a mature mountain region so developed there would be some
peaks not yet lowered to this area, and there would be great val-
leys depressed below it. But would it be incorrect to assume
that in a given area where most lowered, from lo to 25 per
cent of the reduced mountain tops would probably have
reached a fair uniformity of level? This beveling of the hill
tops would be very much further advanced near the coast
than in the interior, thus coinciding with the conditions found
in New England.
According to this view, by the time maturity of topograph-
ic form has been reached, there will be a beveling of hill tops
where the harder gneissic and granitic rock exists, the stream
The Peneplain. — Tarr, 369
valleys standing near the base level and hills of softer strata
standing at levels still lower than those in which the rock is
harder. Areas originally distinctly higher or harder than
usual, or more unfavorably situated, may be less lowered and
more irregular than the surrounding region, though still en-
gaged in an approach to this lower level. A well matured
surface would then present three intergrading stages in differ-
ent places and under different conditions, (i) Local base
levels in the valleys; (2) general well matured topography
with many hills reaching to approximately the same general
level, but with some distinct and many indistinct "monad-
nocks"; (3) exceptional and localized early maturity, found
particularly in the interior. The further the topographic de-
velopment had gone toward old age, the greater would be the
extent of the first two areas. Can any evidence be adduced to
show that New England has ever advanced further in de-
velopment than this stage?
Granting such a reduction, with many hills of hard rock
standing at a moderately regular level if an elevation succeeds,
while the valleys will be deepened and the hills lowered, the
rate of lowering of the hills will be so nearly uniform, since
the climate and rock are so nearly alike, that the measure of
uniformity of upland level will in part be maintained.
Conclusion — The questions raised in this paper are not
against the great importance of subaerial denudation, which
few American geologists are inclined to underestimate. The
stamp of the genius of Powell, Gilbert, Davis and others is too
plainly marked upon the minds of American geologists for any
underestimation of the importance of this. The question I
raise is whether far too much importance has not been as-
signed to this great work. The facts and assumptions upon
which t-he peneplain theory is based are also called in ques-
tion,, and an attempt is made to show that all the phenomena
beheved to indicate the existence of peneplains in New Eng-
land and New Jersey can best be explained without assuming
the reduction of a high mountainous country to the condition
of old age, a condition now nowhere found on the earth.
The alternate hypothesis of beveling down to mature form
is advanced. This hypothesis requires no long periods of rel-
ative quiet, and no assumptions to explain the irregularities of
370 The American Geologist, June, ibU8
the surface, which, by the peneplain theory, call for special
causes whose operation is apparently not otherwise proved,
and which, in part, appear to be hardly probable. The theory
of the peneplain calls for a "nearly featureless plain*'; the
alternate hypothesis of beveling calls merely for a greatly re-
duced, but still markedly irregular surface. To some the
difference between these two hypotheses may seem slight, but
really it is great; for, after the rounded features of maturity
are reached, the advance to such old age topographic features
as the peneplain demands, calls for immense periods of time
with land standing at nearly the same level, conditions which
seem at variance with the facts which geologists have been
collecting in the last half century.
STUDIES ON AN INTERESTING HORNBLENDE
OCCURRING IN A HORNBLENDE GABBRO,
FROM PAVONE, NEAR IVREA,
PIEDMONT, ITALY.
By Fbank R. Van Horn, M. S., Ph. D., Case School of Applied Scieuce,
Cleveland, Ohio.
This hornblende gabbro* consists of the following min-
erals with an approximate estimate of their percentages:
plagioclase, mostly bytownite, 33, hornblende 27, diallage
and hypersthene 25, magnetite and spinel 15. After the
plagioclase, the brown hornblende is the most important
mineral of the rock and makes up about 27 per cent, of the
same. It generally occurs in irregularly shaped but compact
patches, and only occasionally has an approximately idio-
morphic form in the prismatic zone. This is somewhat pe-
culiar as it is one of the most basic constituents of fhe rock,
but the lack of idiomorphism may perhaps be explained by
the high percentage of alkalies which this mineral contains.
/Egirine, arfvedsonite and other minerals with a large per-
centage of alkalies which occur in elaeolite syenytes show
♦For further description of the rocks of this region, see Tschermak's
Mineral. undPetro^^r. Mitth., Bd. XVII, Heft. 5; Frank R. VanHorn,
"Petro^raphische Untersuchungen tlber die Noritischen Gesteine der
Umgebung von Ivrea in Oberitalien."
Harfiblefide from Italy. — Van Horn. 371
an analogous behavior. The prismatic cleavage of the
hornblende is very good, and the cleavage faces possess a
splendent luster so that the angle could be determined with
the goniometer. Measurements on twenty-five different
pieces gave an average value of 124® 18'. Twins after the
orthopinacoid (100) occur at times. The mineral has
a grayish brown streak and a specific gravity of 3.217 to 3.222
at a temperature of 17° C. At red heat it does not melt, but
before the blowpipe at white heat it melts to a brown glass
which is soluble in hydrochloric acid.
The pleochroism is very strong:
a=Ii^ht yellow (Radde, International Color Scale, orange 4, u),
b^brovvn with tinge of red (Radde, vermillion 3, about i-k),
C=^brown with tinge of yellow (Radde, orange 4, about i-k).
The absorption is b> c> a- The extinction angle was de-
termined on the prismatic cleavage faces. Twenty-five
measurements gave an average of 1 1 *^ 5 '. In sections parallel
to (010) the extinction angle was found to be 14*^ 30' to 15®
30' c : ^. This hornblende was carefully isolated from the
rock by means of the Klein solution (cadmium borotung-
state), and this was attended with great difficulty owing to
the nearness of the specific gravity of the hornblende to that
of the diallage also occurring in the rock. The pure min-
eral was analyzed by Dr. M. Dittrich of Heidelberg, Ger-
many. He determined the water not only indirectly by
means of ignition but also according to the direct method
proposed by Sipocz and Ludwig.* The determination of fer-
rous iron was carried out according to the method suggested
by Dolter.f The result of the analysis is found under I,
while for comparison, three other analj'ses are given. Un-
der H is found a hornblende from Vesuvius analyzed by
Rammelsberg, under HI is a second hornblende from Vesu-
vius which Berwerth analyzed, and finally, under IV is found
the analysis of a hornblende from the island of Jan Mayen by
Scharizer.
*E. Ludwig und L. Sipocz, Tschermak's Mitth., 1895, 211 and
Zeitschrift filr Anal. Chem., 17, 206.
fC. Dolter, Zur Kenntniss der Chem. Zus. des Augits, Tschermak's
Mitth., 1877, 281, and 1880, 100.
372 The American Geologist, jime, i89S
1. 11. 111. IV.
SiO, 39.58 39.92 39.80 39 17
TiOg Trace ....
AljOg 14.91 14.10 14.28 14.37
FcgOa 4.01 6.00 2.56 12.42
FeO 10.67 11.03 I9'02 5.86
MnO Trace 0.30 1.5 1
Mgo 13-06 10.72 9.10 10.52
CaO 11.76 12.62 10.73 i\'i^
NagO 2.87 0.55 1.79 2.48
KgO 0.62 3.37 2.85 2.01
HjO 2.79 0.37 1.42 0.39
100.27 98.98 101.55 99'9i
Sp. G. ...3.217-3.222 3.282 3.298 3.33
In the analysis the direct determination of water is given.
Water as ignition was 1.29. The first glance at the analysis
shows us that our hornblende is a very basic one with a high
percentage of alumina and an amount of alkalies which is
quite rare for hornblendes occurring in gabbroid-noritic
rocks. In the Jan Mayen mineral ferric iron predominates,
while the Pavone hornblende has mostly ferrous iron. The
hornblende analysis most nearly resembling ours is the one
from Mt. Vesuvius given under II. It is certain that in the
analysis of many hornblendes, not enough attention has been
paid to the determination of the water which, I think, plays
an important role in the composition of the more basic mem-
bers of this family. Many determine this only by ignition
which always gives too low a result, as part of the oxj-gen
is used for the oxidation of the ferrous iron. The direct de-
termination according to the Sipocz-Ludwig method is apt
to give a result somewhat high. However, in my analysis a
large number of '*blind trials" were made before the analysis
itself was carried out and the percentage of water here is, I
think, very little, if any, higher than it should be. If we
compute Feg O3 as AI2 O3, FeO as MgO, and K^O as NajO,
we can make the following calculation of our analysis:
1. II. 111. IV. V. ' VI.
I ou Molecular Simj^tli- Molecu- Propor-
basis of proix>r- flcatioa lar propor- tions
1(X). tioDS. of III. tioD8 taken, in whole
nnmbers.
SiOj 39-473 42.162 700 12.50 12.50 50
AljOa.iFeaOa) 17.418 18.604 182 3.25 3.25 13
MgO, (FeO).. 18.935 20.225 505 9.01 9.00 36
CaO 11.728 12.527 223 3.98 4.00 16
NagO, (K,0).. 3.285 3.509 56 i.oo i.oo 4
HgO 2.782 2.971 165 2.94 3.00 12
93.621 99.998
Hombleride from Italy, — Van Horn, 373
We therefore obtain the following proportions: 12H2O:
4Na20: i6CaO: 36MgO: 13AI2O3: soSiOj: which written as
a formula gives H^ 4 (Na, K)^ Ca^e (Mg, Fe)3« (Al, Fe)^^
Sigo Ojo?- This on calculation gives the following per cents,
for its theoretical composition:
Calculated. Found. Difference.
SiOg 42.099 42.162 + 0»o63
AlgOa,(Fe80j) 18.607 18.604 — 0.003
MgO, (FeO). 20.207 20.225 + 0.018
CaO 12.573 12.527 — 0.048
NagO, (K,0) 3.480 3.509 + 0.029
HjjO 3.031 2.971 —0.060
99.997 99.Q98
We see from the formula that this hornblende is very
near an orthosilicate, and that it is in reality slightly more
basic than such a one. This is seen more clearly if we simp-
lify still more the formula above given by calculating FcgOg
as AI2O3, FeO and CaO as MgO, Na^ O and K2O as H2O.
We then obtain the following:
1. II. III. IV. V.
I on basis Molecular Simplifl- Molecular
of luU. propor- cation proportions
tions. of III. taken.
SiO, 39.473 44.881 748 3.85 4
AlgOg, (Fe,Oa).. 17.418 19.804 194 i.oo I
MgO, (FeO, CaO) 27.312 31.054 776 4.00 4
H,0,(Na,0,KgO) 3.747 4.260 236 1.21 i
87.950 99-999
We have then HgO: 4MgO: AI2O3: 4Si02 or (H, K,
Na)2 (Mg, Fe, Ca)^ (Al, Fe)2 Si^O^g from which is easily
seen that the proportions are those of an orthosilicate. If
we calculate the theoretical composition of this formula we
obtain as follows:
Calculated. Found. Difference.
SiO, 46.15 44.48 —1.27
AlgOa.lFcgOg). . . 19.61 19.80 +0.19
MgO,(FeO,CaO). 30.76 31.05 +0.29
HgO.lNagO.KgO) 3.46 4.26 +0.80
99.98 99.99
Since the differences are so very slight it seems best, and
certainly much more simple, that we accept this abbreviated
374 The American Geologist, June. i898
formula as the probable one of the hornblende from Pavone,
which would give us the following general formula.
Rj R4 R2 Si40ig
or, writing monovalent elements as divalent ones, we get
Rg Rg Si^Oie
and consider it as an orthosilicate. Scharizer* in 1884 in
his article entitled "Die basaltische Hornblende von Jan
Mayen nebst Bemerkungen iiber die Constitution der thon-
erdehaltigen Amphibole," concluded that there was an or-
thosilicate molecule with the formula (Rj, R")3 (Al, Fe).^
SigOjg, which entered largely into the composition of cer-
tain basic hornblendes. This molecule he called syntagma-
tite, using a name previously given by Breithaupt to certain
hornblendes from Mt. Vesuvius or Monte Somma. The
hornblende from Jan Mayen, the analysis of which is given
above, coincides very nearly with the syntagmatite formula.
Scharizer regards the aluminous amphiboles as composed of
mixtures of the metasilicate molecule Ca (Mg, Fe)3 Si^O,^
(actinolite), and the orthosilicate molecule (Rj, R")3 (Al,
Fe)2 SigOia (syntagmatite). There is little reason why we
should not accept this view, even as, in the feldspar and
scapolite groups, we have accepted the theory that salts of
different acids such as polj^silicates and orthosilicates could
form isomorphous mixtures with each other. The Pavone
hornblende is an orthosilicate like syntagmatite but seems to
have a more complex formula than the latter. We may
consider it as Syntagmatite plus a normal orthosilicate mole-
cule, as follows:
Rs R a ^U^ie = ^8 ^T Sig O, 2 + Rj S1O4.
(Pavone hornblende) (Syntagmatite)
In the past we have been too careless in making our horn-
blende analyses, especially in the water determination, but
this analysis of the Pavone hornblende as well as those of
Scharizer, Berwerth and others makes it seem very probable
that an orthosilicate molecule enters largely into the compo-
sition of the aluminous amphiboles.
*R. Scharizer, Neues Jahrbuch, 1884, II, 142.
Ben Nevis, — Upham, 375
[European and American Glacial Geology Compared. V.]
BEN NEVIS, THE LAST STRONGHOLD
OF THE BRITISH ICE-SHEET.
By Wabren Upham, St. Paul, Minn.
Sailing down loch Lochy and the river of the same name
on the Caledonian Canal steamer "Gairlochy," in the beauti-
fully clear and welcomely warm day of June 29th, last sum-
mer, we had southward a most inspiring view of Ben Nevis
and its great companion mountains extending east to loch
Treig. The upper part of these mountains then bore, as I
counted, about fifty patches and more extensive tracts of
snow, up to a third of a mile in length, lying on their mostly
shaded northern slopes and in their ravines, the remnants of
the abundant and deeply drifted snows of the previous winter,
reinforced in some degree by the frequent later snowfalls of
the spring and early summer.
Here the Scottish Highlands attain their greatest altitude,
the highest point of the somewhat plateau-like top of Ben
Nevis being 4,406 feet above the sea. Until this honor was
determined by exact leveling, it had been generally supposed
to belong to Ben Macdhui* (or Muich Dhui), which has a
similarly massive top, 4,296 feet above the sea, situated fifty
miles northeast of Ben Nevis. On both these mountains snow
drifts usually linger until late in summer, and during many
years are not wholly melted. Like the summer snow arch
spanning the brooklet of its melting in Tuckerman's ravine,
on Mt. Washington, in New Hampshire, these lingering snow-
banks on the highest Scottish mountains show that moderate
climatic changes might bring the beginning of snow and ice
accumulation again upon these lands. Probably the early
Quaternary continental uplifts of North America and of the
west side of the Old World, to the extent of 3,000 to 5,000
feet above their present altitude, which are known by former
river valleys submerged to these depths by the sea on the
eastern and western coasts of the United States and Canada,
in the fjords of Norway, in the bay of Biscay, on the Portu-
guese coast, and on the west coast of Africa south of the
equator, were sufficient to cause the glaciation of the great
*Anp:licized, in accordance with its pronounciation, this name would
be spelled McDewey.
37^ The American Geologist, June,w»i
north temperate and frigid regions of our continent and Eu-
rope which are drift-covered.
An observatory for weather observations was established
on the summit of Ben Nevis in 1883, and hourly records dur-
ing both day and night are taken there for comparison with a
meteorological station close to the sea level at Fort William,
only five miles distant to the west. The mean annual precipi-
tation of rain and snow (the latter being reduced to its equiva-
lent of rain) recorded during the first ten years at the Ben
Nevis observatory was 142.34 inches, being the greatest
known at any locality in Scotland; while for the same period
at Fort William it was 75.79 inches. In comparing this rain-
fall, as Jamieson has done,* with that of other parts of Scot-
land, we find its eastern half to receive much less rainfall
yearly, decreasing eastward from 40 to 25 inches; but in west-
ern Scotland, from Gare loch north-northwest to the Isle of
Skye, a wide belt of the Highlands has 80 inches and upward
of mean yearly rainfall.
Upon this tract of very abundant rainfall and snowfall,
probably the earliest part of the Scottish ice-sheet in the
Glacial period was amassed. It gradually filled the valleys
and glens, and finally overtopped the mountains, excepting
apparently a few of the highest summits. Meanwhile the ice
accumulation extended far outward over the whole country,
into confluence with the ice-sheet of Ireland, the ice-fields
of the Southern Uplands, of the mountains in the English
Lake District, and of Wales; and, on the east, it became con-
fluent with the great ice-sheet deploying from the mountain-
ous Scandinavian plateau on the wide low plain that is now
covered by the shallow North Sea.
When the Glacial period ended, the confluent European
ice-sheet in its departure doubtless became again divided, as
during the early states of growth, into separate parts flowing
outward from the great central tracts of maximum snowfall.
The courses of glacial striae, and of the dispersal of drift, give
clear evidence of the areas which thus preserved the latest
remnants of the formerly confluent icefields. In the British
Isles, probably the last remnant to melt away was in western
Scotland, lingering somewhat longer, on account of the alti-
*Quart. Jour. Geol. Soc, XLVIII (1892), 5-28.
Ben Neins. — Upham, 377
tude of the mountains and the very plentiful snowfall, than
any part of the icefields of Ireland,, Wales, and England.
Many recessional moraines of that closing stage of the British
glaciation in the neighborhood of Ben Nevis were ob-
served and mapped by me in Glen Roy, in the Spean and
Lochy valleys, and in Glen Nevis, along a distance of about
twenty miles from northeast to southwest.
The day of my ascent of Ben Nevis, June 30th, had so
fair a morning that it beguiled me to delay until in the later
part of the day I entered clouds and a rainstorm on the sum-
mit. Instead of having the wide outlook that was thus pre-
vented, I found in the observatory library Sir Archibald
Geikie's very instructive book, "The Scenery of Scotland,"
in which I read there an hour, taking notes on the Great
Glen, the Parallel Roads, Ben Nevis, etc. From the bridle
path, in ascending, I had noted four small moraines stretch-
ing across Glen Nevis at the southwestern base of the moun-
tain, between three and five miles from Fort William. On my
return I noted four or five other little moraines, crossing the
lower part of Glen Nevis, on the farms at the foot of the bridle
path.
Next to the north, a larger moraine extends a miles east-
ward from the Nevis bridge ; and between one and two miles
farther north a belt of such morainic drift knolls and small
ridges, 10 to 30 feet high, strown with many boulders, runs
from the northwest base of Ben Nevis west and northwest
across the Lochy valley to Banavie and the adjoining hills.
Thence passing on July ist, and again on the 3rd, by the
railway northeast to Roy Bridge station, I counted and ap-
proximately mapped nine narrow moraines, at intervals vary-
ing from a quarter of a mile to one mile apart, in the distance
of about six miles from the new Inverlochy castle to the most
northeastern one noted, which crosses the Spean valley from
north to south and southeast about a third of a mile east of
Spean Bridge station. These moraines vary from a few rods
to an eighth of a mile in width, and reach one to two miles
across the valley which is followed by the railway. Their hill-
ocks and ridges of bouldery drift rise only 10 to 20 feet
above the smooth and cultivated intervening parts of the val-
ley. The moraine noted close east of Spean Bridge appears
to mark the place of the ice-front when it was the barrier of
37^ Tlie Americafi Geologist, Juae, i8»8
the latest stage of Lake Roy, with outflow at the col east of
loch Laggan.
In going up Glen Roy, I found moraine drift amassed
east of the south part of Bohuntine hill, and more remarkably
about a mile further north, adjoining the northeastern curving
base of this hill, with stratified overwash drift, which was de-
posited in lake Roy, extending with decreasing hight from
the last mentioned moraine for a half mile or more up the glen.
From the sharp bend of the highway on this prominent mo-
raine, the best view of the Parallel Roads, running along the
higher mountain sides, is obtained.
Again, about two miles and a half farther up this narrow
valley, another definite moraine was found, nearly blocking
the glen, but cut in a deep gap by the stream, which flows
some 200 feet below the crest of the moraine.
But the most interesting morainic accumulation (as Prest-
wich regarded it to be) occurs between two and three miles
farther up Glen Roy, extending about three-fourths of a mile
from north to south across the mouth of the river Turret,
tributary to the Roy from the northwest. This massive drift
accumulation rising 75 to 100 feet above the rivers Turret,
and Roy, which I think to be a moraine amassed in the edge
of lake Roy at its highest stage, consists largely of stratified
drift, varying from laminated silt to coarse gravel wjth angu-
lar boulders up to three or four feet in diameter. Jamieson
thinks it a delta of the Turret, but this seems inconsistent with
the open lower valley of that stream before it intersects this
drift deposit. More in harmony with the other observations
of moraines before not.ed, I believe Prestwich's view the true
one, after reading Jamieson's discussion of it and examining
the locality.
The reference of the Parallel Roads to glacial lakes barred
by the waning Scottish ice-sheet, which Jamieson has pre-
sented in his latest paper on this subject, before cited, instead
of his earlier explanation by barriers of local valley glaciers,
seems to be supported by the series of about twenty retreatal
moraines which have been here described in the order in
which they were observed, opposite to the chronologic order
of their formation by this receding remnant of the ice-sheet.
Step by step, as shown by these moraines, the vanquished
Ben Nevis. — Upham. 379
ice-sheet withdrew until its last stronghold, probably the latest
in Britain, was this highest mountain of Scotland.
The difficulty of supposing valley glaciers of later origin
to have obstructed the Great Glen and Glens Spean and Roy
is well stated by Jamieson, showing rightly, as I think, that
the Parallel Roads are a record of the end of the general gla-
ciation of Scotland, rather than of a later stage or epoch of
renewed ice accumulation. Similar difficulties seem to me to
oppose the view of Prof. J. B. Tyrrell, who has supposed an
ice-sheet first amassed on the Cordilleran area of North Amer-
ica, then waning, and succeeded by a chiefly later ice-sheet on
the Keewatin region of the interior of this continent, which
in its turn decreased, to be followed in time by the chief ac-
cumulation of a Laurentide or Labradorean ice-sheet.* On
the other hand, my interpretation of our glacial striie and drift
transportation, .with frequent changes of the glacial boundar-
ies and overlapping of the drift deposits, refers the glaciation
of these three great regions of North America, like that of the
British Isles and continental Europe, to the same time, with
confluence during the greater part of the Glacial period, and
with later division into separate icefields, corresponding to the
great areas of glacial radiation, when the previously united
and continuous North American ice-sheet melted away.
In connection with the moraines of Glen Roy and the
lower part of the Spean valley, brief mention ought to be made
of the three very admirably developed moraines which ex-
tend eastward from the east end of the Creag Dhubh mount-
ain mass south of the Glen Glaster col. These moraines,
formed during the Glaster stage of lake Roy, reach four miles
or more, athwart the Spean valley six to eight miles east of the
mouth of Glen Roy. The more southern and western of the
three moraines curves in a semicircle across the rather level
moor east of Tulloch station, and its northern part runs along
the northern foot-slope of the great mountain east of loch
Treig, there being represented by three or four district mor-
ainal lines on the steep rock slope.
Another paper, for which I took plentiful notes, might be
written on the very interesting kames and kame plateaus
which are admirably displayed along an extent of nearly two
♦Journal of Geology, IV, 811-815, Oct.-Xov., 1896; VI, 147-160, with
maps, Feb. -March, 1898.
380 The American Geologist. Jane. i898
miles between the mouth of loch Treig and Tulloch. At this
locality Louis Agassiz, in his visit to the Parallel Roads in
1840, expressed his delight and enthusiasm in finding these
sure records of glacial action, unsurpassed, as he affirmed, by
any place in the Alps. While lake Roy in its latest and most
extended stage was forming the lowest of the Roads, the only
one found in the Spean valley, the site of loch Treig was oc-
cupied by ice, as is known by the absence of that Road on the
mountain slopes inclosing the loch.
The absence of trees or even bushes from the greater part
of the country here described made it very easy to trace the
moraines, as on the western prairies and plains of the nor-
thern United States. As was said at the close of my second
paper in this series, again it may be remarked here that prob-
ably many such small retreatal moraines will be found in
the valleys of the White mountains of New Hampshire, and
of the Green and Adirondack mountains, when the general
clearing away of the forests shall favor their discovery and
mapping. Probably Mts. Washington and Marcy, like Ben
Nevis, were fastnesses latest relinquished by the waning gla-
ciation of the surrounding country at the end of the Ice age.
REVIEW OF RECENT GEOLOGICAL
LITERATURE.
Mineral Resources of the United States, i8q6. By David T. Day.
(Eighteenth Annual Report, U. S. Geol. Survey, for 1896-97; Part V, in
two volumes: I. Metallic Products and Coal, pp. xii, 642; II. Nonmetaliic
Products, except Coal, pp. 643-1400. Washington, 1897.)
These separately indexed volumes, compiled with the aid of expert
assistants, are published before the other parts of this annual report.
that the statistics and discussion of the year's mineral industries and
production shall be given as early as possible to those engaged in
mining, quarrying, and all related industries and manufactures. For
this purpose, separate brochures of many chapters, as those treating
of iron and steel, building stone, clay-working, mineral paints, abrasive
materials, etc., have been issued, as the printing advanced, before the
completion of the whole, which was issued about May ist of this year,
as early as was consistent with accurate collection and presentation of
the extensive details of the subject in its many departments.
Review of Recent Geological Literature, 381
The report on iron ores, by John Birkinbine, occupies 28 pages,
showing a product of 16,005,449 tons (long tons, of 2,240 pounds), a
slight increase over 1895, and nearly equal to the maximum iron ore
production, which was attained in 1892. A very valuable report on
iron and steel and allied industries is presented by James M. Swank,
the general manager of the American Iron and Steel Association, in 90
pages. This includes statistics for long series of years in the United
States and in all iron-working countries, with tables of their produc-
tion, and of their exports and imports, of iron and steel and of coal
and coke. A final table states the railroad mileage of all parts of the
world at the end of the year 1895, the United States having 181,717
miles, Europe in total, 155,284 miles, and the entire world, 433,953 miles.
The product of gold by the United States in 1896 was the greatest
ever attained, being valued at $53,088,000. It was an eighth more than
in 1895, and a quarter more than in 1894. The commercial value of the
silver produced was $39,655,000, showing also a considerable increase
over the preceding years.
Copper production attained the value of $49,456,603, of which 59 per
cent, was exported. In similar manner each branch of our mining,
quarrying, clay-working, and other industries developing -the geologic
resources of the United States is noted in much descriptive detail,
statistics, and comparison with previous years and other countries.
Among the contributors of these special reports are Charles Kirch-
hoflF, on copper, lead, and zinc; R. L. Packard, on aluminum; John
Birkinbine, on the ores of iron and manganese; Joseph Wharton, on
nickel and cobalt; Edward W. Parker, on antimony, coal, coke, asphal-
tum, soapstone, abrasive materials, sulphur and pyrites, gypsum, salt,
fluor spar and cryolite, mica, asbestos, mineral paints, and barytes; F.
H. Oliphant, on petroleum and natural gas: William C. Day, on stone;
Jefferson Middleton, on clay-working statistics; Heinrich Ries, on the
clay-working industries, and on feidspar and quartz; Spencer B. New-
berry, on Portland cement; Uriah Cummings, on rock certient; George
F. Kuiiz, on precious stones; and Albert C. Peale, oii mineral waters.
The total value of the mineral products of the United States for
the year 1896 is shown as $623,717,288, being about $1,090,000 more
than in 1895, and two-fifths more than in 1880.
For geologists, seeking knowledge of the mode of occurrence of
valuable geologic formations and their origin (rather than the results
of their working, which are of chief commercial importance), the most
interesting paper of this report is by George F. Becker, on "The
Witwatersrand Banket, with Notes of other Gold-bearing Pudding-
stones,'* in 32 pages, with a map. The gold ores now worked on so
vast 'scale in the vicinity of Johannesburg and elsewhere in the Trans-
vaal are found to be in marine gravel and sand, stretching along the
forn7er southern shores of the African continent. In the more north-
erly adjacent gold districts, extending into Mashonaland the gold
occurs in veins, mostly in schists and granitoid rocks; and there many
abandoned sites of former mining and smelting have been discovered.
382 The American Geologist Jane, i»9s
indicating that region to be probably the Ophir of the ancients. Rivers
flowing thence to the sea brought the gold-bearing littoral marine sands
and gravels, of Paleozoic age (perhaps Devonian or Lower Carbon-
iferous), which have yielded from $20,000,000 to $38,000,000 of gold
yearly since 1891. Similar auriferous manne deposits in many other
parts of the world, including Nova Scotia, North Carolina, the Black
Hills, the Big Horn range, California, and Alaska, are also noted in
this paper. Indeed, Dr. Becker shows that nearly all pre-Tertiary
gold-bearing gravels are of such marine deposition as in the Trans-
vaal, w. u.
Reconnaissance of the Gold Fields of Southern Alaska, with some
Notes on General Geology, By George F. Becker. (From the Eigh-
teenth Annual Report, U. S. Geol. Survey, for 1806-97, Part HI, Eco-
nomic Geology, pp. 1-86, with 31 plates and 6 figures in the text. Wash-
ington, 1898.)
This report presents a great amount of detailed geologic informa-
tion, mainly relating to the gold mining and gold-bearing rocks at
Juneau and other localities on the southern coast of Alaska, based on
observations by the author in 1895. It will be read with great interest
on account of the recently discovered and wonderfully rich placer mines
of the Uppei Yukon district, which are the subject of the next paper.
The product of gold from the Alaska-Treadwell mine in the fifteen
years since it was opened, up to the end of the year 1896,* was $7,028,649.
Its ore in 1893 and 1894 yielded only $3.20 per ton, and the cost of its
working, with daily wages from $2 up to $5, was only $1.35 per ton.
This mine in 1889 to 1893 produced about two-thirds of all the gold
mined in Alaska; but since 1893 its proportion has been a half to a
third, the whole gold production of Alaska in 1896 being estimated, by
the director of the mint, as $2,055,710. w. r. .
Iowa Geological Survey, Administrative Reports, (Iowa Geol.
Survey, vol. 8, pp. 9-49, plates 1-2, 1898.)
The sixth annual report of the state geologist, Samuel Calvin, gives
a detailed statement of the work of the survey for 1897. This report
shows that the activities of the survey have been directed toward a
number of important lines of research, among which are special work
on the drift and on the Carboniferous, investigations and aid in de-
veloping the natural resources of the state, collecting of mineral statis-
tics and areal county work. During the past year areal county work
has been completed in the following six counties: Dallas, by A. G.
Leonard; Scott, by W. H. Norton; Decatur and Plymouth, by H. F.
Bain; Delaware and Buchanan, by Samuel Calvin. It is expected
that the reports on these counties will be published in the present
volume (VIII) of the survey. In previous years twenty counties have
been mapped and reported upon, making a total of twenty-six coun-
ties in which the work has been completed.
The report of the assistant state geologist, H. F. Bain, presents
statements of reconnaissance work conducted in a number of counties.
Review of Recent Geological Literature. 383
one of the chief points of study being the separation of the different
drift sheets.
A welcome addition to the information presented by the Iowa
survey consists in a report on the mineral production of the state,
the statistics for which were collected and tabulated by the secretary
of the survey, Miss Nellie E. Newman. The total value of the mineral
production of Iowa for 1897 was $7,446,800.42, of which nearly five-
sevenths represents coal. u. 8. g.
Kalgoorlite — a new telluride mineral from Western Australia, By
E. F. PiTTMAN, (Records Geol. Survey, N. S. Wales, vol. 5, pt. 4, pp
203-204, Feb. 1898.)
A brief description is given of this mineral which occurs with the
rich telluride deposits of Kalgoorlie in crushed and foliated quartz por-
phyry dykes. Among the tellurium minerals is an iron black mineral
with a specific gravity of 8,791. It is massive and has a sub-conchoidal
fracture. An analysis shows:
Mercury ia86
Gold 2a 72
Silver . .• 30.98
Copper 05
Sulphur 13
Tellurium ; 37.26 (b y difference).
100.00
From this analysis HgAugAggTeg is calculated as the empirical for-
mula. The kalgoorlite occurs associated with pale yellow calaverite.
u. s. G.
Catalogue of the Tertiary Mollusca in the Department of Geology ^
British Museum {Nat, Hist.). Pt. /. The Australian Tertiary Mollus
/:a. By GEORGE F. Harris. (8vo; xxvi and 407 pp., 8 pis.; London,
1897.)
The catalogues published by the trustees of the British museum
generally contain much more than their titles imply. In them will
often be found some of the latest applications of the laws of evolution
and the elucidation of new and important principles of morphology.
Discussions of this nature have added value and weight from the
intimate association of specimens and ideas, for usually curators
of collections and custodians of ideas are too frequently dissociated.
It is, therefore, a wise policy to engage the services of the highest
talent in the preparation of the catalogues or reports on various col-
lections or classes of organisms.
Thirteen volumes on fossil vertebrates, eight on fossil inverte-
"brates, and three on fossil plants have already been published in
this series, and Dr. Woodward states that thirty volumes more will
be needed to include the remainder of the plants and Mollusca, the
whole of the Brachiopoda, Annelida^ Arthropoda, Echinodermata,
and Ccelenterata.
The present catalogue of the "Tertiary Mollusca of Australasia" is
^ased upon the study of large collections, especially rich in well-
384 The American Geologist, June, isss
preserved Gastropoda, Mr. Harris has thus been enabled to study
the larval shells and the stages of growth with accuracy and pre-
cision. In studies of phylogenies and in the systematic classification
of the Gastropoda the results are important. The scaphopods and
lamellibranchs are also included, but owing to meager material they
have afforded insufficient data for general conclusions.
Some valuable suggestions are given governing the correlations of
phylogeny with chronology. Thus, a genus that has survived from
early Mesozoic times, with but little modification in the later stages
of its history, has had its day and settled down to a more or less
fixed form. Such a genus is of little use for homotaxial purposes,
though interesting phylogenetically. In the Tertiary the determina-
tion of homotaxis can best be based upon families which originated
in Jurassic or Cretaceous times and reached the Eocene with strong
tendencies to variation; yet, at the same time, the members should be
capable of wide and rapid dispersion.
The general law is suggested that when the main features of
ornament are foreshadowed in the early nepionic or brephic stage,
and especially when they obtain even in the protoconch, that orna-
ment may be regarded as of value in the determinatibn of species.
On the contrary, when the ornament does not make its appearance
until ihe late neanic or adolescent stage, and, even in an elementary
sense, is not completed until what may be regarded, by analogy,
as the early mature stage, that ornament merely characterizes the
individual, and is only of negative use for the purposes of classifica-
tion.
As is well known, the size of the protoconch is variable, even in
the offspring of a single individual, that difference being commonly
attributed to carnivorous proclivities on the part of the larger speci-
mens when in the embryonic stage. The. author also notes that the
size of the protoconch does not seem to have much influence in
determining the size of the shell in the adult. The larger protoconch
is not very often accompanied by the production of a larger adult
shell than that which comes from a much smaller protoconch, that is,
in the same species. There are, however, exceptions to this, and, cor-
relatively, it may be noted that the shape of the protoconch occa-
sionally determines the general shape of the shell.
Further interesting observations are made on the development of
the Volutidcp, the columellar plications in Mitra, and the recurrence
of a type of ornamentation in a species of Cerithhan. AH the genera
are briefly described, and the type species is given. The notes on the
species are preceded by a list of the synonymy and bibliographic
references.
Some changes in the nomenclature of the genera will not meet
with general endorsement, although the principles adopted are, for
the most part, those approved by the best authorities. Thus, the
name Xucu/ana (Link. 1807) is used instead of Ltda (Schum., 1817)
on the ground of priority. Nuculana however was given by Link
Review of Recent Geological Literature , 385
as a mere verbal substitute for Nucula (Lam., 1799), as Dr. W. H.
Dall and others have shown. Link's diagnosis applies to Nucula
and not to Leda for he says that the shell is "smooth, closed all
round." Nuculana (Link non Adams) is therefore "an exact syno-
nym" of Nucula and cannot be sustained on the ground of priority.
Consequently the family name Nuculanidce ^ Adams, cannot be re-
tained for Ledidce, C. e. b.
Vestdnafaltet : En Petrogenelisk Studie. (With an English Summa-
ry.) Af Helge Backstrom. (127 pp., 8 pis. Kongl. Svenska Veten-
skaps-Akadamiens Handlingar, Bandet 29, No. 4, 1897.J
The crystalline schists of the Vestana region, which lies in north-
eastern Scania, southern Sweden, have been studied and mapped in
detail by Baron De Geer of the Geological Survey of Sweden.
According to De Geer, they form an uninterrupted series of strata,
striking northwest to northeast and dipping steeply to the west.
From the youngest downward the sequence is as follows:
KlafiTStorp schis'ts.
Dyneboda gneiss. .
Fine-irraiDed Ki'c^y gneiss.
Dioryte-schistf
Mica qaartzyte.
( Fine-RTained, commonly red eruoiss
( with layers of dioryte-schist.
r Mica-schist.
I Quartzyte.
Mica-schist with conglomerate.
L Qaartzyte with iron ore.
Black, hornblende-bearing, dense
fine-grained gmeiss.
Dense fine-grained gneiss — -{
Grey dense fine-grained gneiss.
Grey gneiss, less fine-grained.
These gneisses and schists form a part of the Swedish Archaean
(Lower Algonkian) and have been the subject of an able and pains-
taking investigation, from a petrogenetic point of view, by Dr.
Backstrom.
Younger than the gneisses or crystalline schists there occur in the
Vestana region numerous intrusive granite massives. Of these
granites there is a prevalent fine-grained type ("Halen"-granite) and
a less prevalent coarse-grained type ("Semshog" granite). These two
types are closely related mineralogically and structurally. Both are
characterized by scarceness of the ferromagnesian minerals and the
predominance of microcline and quartz over oligoclase; hornblende
is altogether absent; only biotite occurs; allanite and titanite are
constant and often macroscopic constituents. Large microcline
crystals are a characteristic feature of both granites, and give to
them a porphyritic habit. This structure is called by Dr. Backstrom
pseudoporphyritic, because the microcline does not belong to a first
generation of crystallization, but, on the contrary, is younger than
386 The American Geologist, June, i898
the mica, oligoclase and orthoclase. There has been considerable
recrystallization in these granites, which has affected the biotite, the
oligoclase, the microcline and the quartz as well as the secondary
minerals, and has thereby more or less altered the original structure.
All the granites show the effect of pressure, but are distinctly sep-
arated by mineralogical composition from the gneisses. A crushed
variety of the fine-grained granite is a granulite associated with the
Dyneboda gneiss.
The mica-quartzyte belt is at its base a pure quartzyte. The hem-
atite ore which this quartzyte contains is concentrated in narrow bands
which are sometimes folded. The conglomerate, contained in the
overlying mica-schist, is composed, for the most part (95 per cent),
of boulders resembling the quartzyte beneath and for the remainder,
of vein material. The mica-schist, or uppermost member of the
mica-quartzyte band, is rich in'muscovite and alumina minerals such
as andalusite, cyanite, ottrelite and fibrolite. From this formation
the author has elsewfcere* described a "manganandalusite" which
has the physical properties of common andalusite with the exception
of a grass-green color and a strong pleochroism. The mica-quartzyte
belt is connected with the conformable underlying dense fine-grained
gneisses through gradations of mica-schist. Dr. Backstrom con-
siders it possible, therefore, that the granite, being younger than the
gneiss, is also younger than the mica-quartzyte. But none of the
rocks of the latter formation now exhibit any distinct proofs of an
original contact structure, the later tectonic movements having
obliterated any older structure.
Amphibolites are associated subordinately with all the formations
of the region, except the granites. Their principal occurrence is
as a bed 100 meters thick between the quartzyte and the fine-grained
gneisses. This bed, it is supposed, has been folded and appears as
two beds enclosing the quartzyte. This amphibolite is composed of
hornblende and plagioclase with subordinate biotite, orthoclase,
quartz and epidote. Structurally three varieties are distinguished by
the character of the hornblende: the feldspar always occurs in small
anhedrons; the hornblende and mica may occur in anhedral grains
or the hornblende occurs as idiomorphic prisms in a feldspathic
ground-mass, or, finally, it may appear as large irregular grains.
These amphibolites have the chemical composition of a diabase and
the mineralogical and structural characters which have been known
to be produced by the action of contact-metamorphism on a diabase.
They lie within the contact zone of the granites, already described.
For these reasons the amphibolite bed is thought to be either a
diabase-flow or a layer of diabase tuff, while some of the minor
occurrences of amphibolite are considered to be altered dyke rocks.
In the Vestana region there are no unaltered diabases, gabbros or
diorytes older than the intrusive granites or older than the orographic
movement. There are, however, numerous dykes of unaltered
*GeologiHka FAn^uiuKCiii* FOrhantllinffar, Stockholm, 1896, lb, p. i^.
Atithors' Catalogue, 387
diabases and norytes cutting the granites and showing themselves
to be younger than the folding.
Conformably underlying the quartzytc and amphibolyte beds,
occur the gneisses. The gneiss series begins with a dense fine-
grained gneiss and passes by insensible gradations into a less fine-
grained and more highly metamorphosed grey feldspathic gneiss,
which covers the greater part of the eastern portion of the Vestana
region. Inter bedded with the gneisses are conformable layers of
mica-schist, which show the structure and composition of sediments.
The gneisses themselves have the chemical composition of quartz-
diorytes and also show quartzes of the form common to the intelluric
quartzes of effusive rocks. The gneisses are therefore regarded as
resulting from the mechanical destruction of a quartz-porphyryte-tuff.
The southwestern and southern part of the area is occupied by a
granite-gneiss. It is provisionally explained as an intrusive granite
altered to a gneiss.
All the rocks of the Vestana region show more or less the effects
of pressure, though only locally are the effects marked. Contact-
metamorphism, however, has widely and strongly affected the sedi-
ments. In the quartzyte beds alone has this metamorpliism been
obliterated by the subsequent tectonic movements. This folding,
affecting granite and sediments alike, pressed down between the
lower and more highly metamorphosed gneisses a small part of the
mica-quartzyte, once more widely extended, and the highest member
of the gneissic series, and thereby saved them from removal by
erosion.
The paper is accompanied by excellent photomicrographs and is a
suggestive contribution to the understanding of the pre-Cambrian
crystallines. The value of the petrographic study suffers some loss
in the brevity of the English summary. F. b.
MONTHLY AUTHORS^ CATALOGUE
OF American Geological Literature,
Arranged Alphabetically.*
Adams, F. D.
The deformation of rocks under pressure. [Abstract.] (Eng. and
Mining Jour., vol. 65, p. 522, Apr. 30, 1898.)
Adams, G. I.
Physiography of southeastern Kansas. (Kansas Univ. Quarterly,
vol. 7, ser. A, pp. 87-102, Apr. 1898.)
*Thi3 list includes titles of articles received ap to the 20th of the preceding
month, including general geolovyt physiography, paleontology, petrology and
mineralogy.
388 The American Geologist June. 1888
Baker, Marcus.
A century of geography in the United States. (Science, new ser.,
vol. 7, pp. 54i-S5i» Apr. 22, 1898.)
Bather, F. A.
Wachsmuth and Springer's classification of crinoids. (Natural
Science, vol. 12, pp. 337-345, May 1898.)
Becker, G. F.
On the determination of plagioclase feldspars in rock sections. (Am.
Jour. Sci., ser. 4, vol. 5, pp. 349-354, pl. 3, May 1898.)
Beede, J. W.
Variations of external appearance and internal characters of Spirifer
cameratus Morton (Kansas Univ. Quarterly, vol. 7, pp. 103-105, pi.
6, Apr. 1898.)
Bentley, W. A., and Perkins, G. H.
A study of snow crystals. (Appletons' Pop. Sci. Monthly, vol. 53,
pp. 75-82, May 1898.)
Berkey, C. P.
Geology of the St. Croix dalles. III. (Am. Geol., vol. 21, pp.
270-294, pis. 17-21, May 1898.)
Birkinbine, John.
Iron ores. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 23-50,
1897.)
Birkinbine, John.
Manganese ores. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5,
pp. 291-328, 1897.)
Branner, J. C.
Geologv in its relations to topography. (Am. Soc. Civil Engineers.
Trans., vol. 39, no. 821, pp. 53-95, pis. 1-2, June 1898.)
Broad head, G. C.
Major Frederick Hawn. (Am. Geol., vol. 21, pp. 267-269, pi. 16,
May 1898.) *
Chester, A. H.
On krennerite, from Cripple Creek, Colorado. (Am. Jour. Sci.,
ser. 4, vol. 5, pp. yj^'ZIT, May 1898.)
Cummings, Uriah.
Rock cement. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp.
1 178-1 182, 1897.)
Dall, W. H.
Synopsis of the recent and Tertiary Psammobiidae of North Amer-
ica. (Acad. Nat. Sci. Phila., Proc, 1898, pt. i, pp. 57-62, 1898.)
Day, W. C.
Stone. (U. S. Geol. Survey, 18th Ann. Rept., pt. 5, pp. 949-1068,
1897.)
Fuller, M. L.
Champlain submergence in the Narragansett bay region. (Am.
Geol., vol. 21, pp. 310-321, May 1898.)
Authors' Catalogue, 389
Gallouedec, M. L.
Man's dependence on the earth. (Applctons* Pop. Sci. Monthly,
vol. 53, pp. 99-107, May 1898.)
Gilbert, G. K.
Description of the Pueblo quadrangle. (U. S. Geol. Survey, Geo-
logic Atlas of the U. S., folio 36, Pueblo folio, Colo., 1897.)
Goldsmith, E.
Volcanic rocks of Mesozoic age in Pennsylvania. (Acad, Nat. Sci.
Phila., Proc, 1898, pt. i, pp. 90-97, pIs. 2-5, 1898.)
Goldsmith, E.
The petrifaction of fossil bones. (Acad, Nat, Sci. Phila., Proc,
1898, pt I, pp. 98-100, 1898.)
Grant, U. S.
Sketch of the geology of the eastern end of the Mesabi iron range
in Minnesota. (Engineers' Year Book, University of Minnesota, pp.
49-62, 1898.)
Griswold, L. S.
The geology of Helena, Montana, and vicinity. (Jour, of the Ass.
of Engineering Soc, vol. 20, no. i, Jan. 1898; 18 pp.)
[Hawn, Frederick.]
Major Frederick Hawn, by G. C. Broadhead. (Am. Geol., vol. 21,
pp. 267-269, pi. 16, May 1898.)
Hull, Edward.
Professor J. W. Spencer on changes of level in Mexico, (Geol.
Mag., new ser., dec. 4, vol. 5, pp. I93-I95. May 1898.)
Iddings, J. P.
Chemical and mineralogical relationships in igneous rocks. (Jour.
Geol., vol. 6, pp. 219-237, pis. 9-10, Apr.-May 1898.)
Jaggar, T. A., Jr.
Some conditons affecting geyser eruption. (Am. Jour. Sci., ser.
4, vol. 5, pp. Z2Z-ZZZ, May 1898.)
Keyes, C. R.
Modern stratigraphical nomenclature. (Science, new ser., vol. 7,
pp. 571-572, Apr. 22, 1898.)
Keyes, C. R.
The myth of the Ozark isle. (Science, new ser., vol. 7, pp, 588-589,
Apr. 29, 1898.)
Kirchhoff, Chas.
Copper. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 185-235,
1897.)
Kirchhoff, Chas.
Lead. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 237-262,
1897.)
Kirchhoff, Chas.
Zinc, (U. S. Geol, Survey, i8th Ann. Rept., pt. 5, pp, 263-280,
1897.)
390 The American Geologist, juno,i8»8
Knight, W. C.
Some new Jurassic vertebrates from Wyoming. (Am. Jour. Sci.,
ser. 4, vol. s, pp. 378-381, May 1898.)
Kunz, G. F.
Precious stones. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp.
1183-1217, 1897.)
Leverett, Frank.
The weathered zone (Yarmouth) between the Illinoian and Kansan
till sheets. (Jour. Geol., vol. 6, pp. 238-243, Apr.-May 1898.)
Leverett, Frank.
The Peorian soil and weathered zone (Toronto formation?). (Jour.
Geol., vol. 6, pp. 244-249, Apr.-May 1898.)
Linton, Edwin.
On the formation of new ravines. (Am. Geol., vol. 21, pp. 329-330,
May 1898.)
Mabry, T. O.
The brown or yellow loam of north Mississippi, and its relation to
the northern drift. (Jour. Geol., vol. 6, pp. 273-302, Apr.-May 1898.)
Middleton, Jefferson.
Statistics of the clay-working industries in the United States in
1896. (U. S. Geol. Survey, 18th Ann. Rept., pt. 5, pp. 1077-1104, 1897.)
Moore, Chas.
The Ontonagon copper bowlder in the U. S. National Museum.
(U. S. Nat. Museum, Rept. for 1895, pp. 1021-1030, pis. 1-2, 1897.)
Moses, A. J.
An introduction to the study and experimental determination of
the characters of crystals. Part II. The optical characters. (School
of Mines Quarterly, vol. 19, pp. 1 13-149, Jan. 1898.)
Newberry, S. B.
Portland cement. (U. S. Geol. Survey, i8th Ann. Rept, pt 5, pp.
1169-1177, 1897.)
Newsom, J. F.
A geological section across southern Indiana, from Hanover to
Vincenaes. (Jour. Geol., vol. 6, pp. 250-256, pi. 11, Apr.-May 1898.)
Nordensl<jold, Otto.
Tertiary and Quaternary deposits in the Magellan territories. (Am.
Geol., vol. 21, pp. 300-309, May 1898.)
Ollphiant, F. H.
Petroleum. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp.
747-893, 1897.)
Oliphant, F. H.
Natural gas. (U. S. Geol. Survey, i8th Ann. Rept., pt S, pp.
895-918, 1897.)
Osborn, H. F.
A complete skeleton of Teleoceras, the true rhinoceras from the
upper Miocene of Kansas. (Science, new ser., vol. 7, pp. 554-557, Apr.
22, 1898.)
Authors' Catalogue, . 391
Osborn, H. F.
A complete skeleton of Coryphodon radians — notes upon the loco-
motion of this animal. (Science, new sen, vol. 7, pp. 585-588, Apr.
29. 1898.)
Packard, R. L.
Aluminum. (U. S. Geol, Survey, i8th Ann. Rept., pt. 5, pp.
281-285, 1897.)
Parker, E. W.
Antimony. (U. S. Geol. Survey, i8th Ann. Rept., pt 5, pp.
343-348, 1897).
Parker, E. W.
Coal. (U. S, Geol. Survey, i8th Ann. Rept, pt. 5, pp. 351-632,
1897.)
Parker, E. W.
Coke. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 659-746,
1897.)
Parker, E. W.
Asphaltum. (U. S. Geol. Survey, i8th Ann. Rept, pt. 5, pp.
919-948, 1897.)
Parker, E. W.
Soapstone. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp.
1069-1075, 1897.)
Parker, E. W.
Abrasive materials. (U. S. Geol. Survey, i8th Ann, Rept., pt. 5,
pp. 1219-1231, 1897. )
Parker, E. W.
Sulphur and pyrites. (U. S. Geol. Survey, i8th Ann. Rept, pt. 5,
pp. 1243-1261, 1897.)
Parker, E. W.
Gypsum. (U. S, Geol. Survey, i8th Ann. Rept , pt 5, pp.
1263-1271, 1897.)
Parker, E. W.
Salt. (U. S. Geol. Survfey, i8th Ann. Rept, pt 5, pp. 1273-1313,
1897.)
Parker, E. W.
Fluorspar and cryolite. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5,
pp. 1315-1316, 1897.)
Parker, E. W.
Mica. (U. S. Geol. Survey, i8th Ann. Rept, pt S, pp. 1317-1321,
1897.)
Parker, E. W.
Asbestos. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp. 1323-1331,
1897.)
Parker, E. W.
Mineral paints. (U. S. Geol. Survey, i8th Ann. Rept, pt 5, pp.
1335-1347, 1897.)
392 The American Geologist. June, i8«s
Parker, E. W.
Barytes. (U. S. Geol. Survey, i8th Ann. Rept, pt. 5, pp. 1348-1350,
1897.)
Peale, A. C.
Mineral Waters. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5, pp.
1369-1389, 1897.)
Perkins, G. H. (Bentley, W. A., and)
A study of snow crystals. (Appletons' Pop. Sci. Monthly, vol. 53,
pp. 75-82, May 1898.)
Rand, T. D.
The Birdsboro trap quarries. (Acad. Nat. Sci. Phila., Proc, 1898,
pt. I, p. ID, 1898.)
Ransome, F. L.
Some lava flows of the western slope of the Sierra Nevada, Califor-
nia. (Am. Jour. Sci., ser. 4, vol. 5, pp. 355-375, May 1898.)
Rhoads, S. N.
Notes on the fossil walrus of eastern North America. (Acad. Nat.
Sci. Phila., Proc, 1898, pt. i, pp. 196-200, 1898.)
Rickard, T. A.
The minerals which accompany gold, and their bearing upon the
richness of ore deposits. (Eng. and Mining Jour., vol. 65, pp. 494-495,
Apr. 23, 1898.)
Ries, Heinrich.
The clay-working industry in 1896. (U. S. Geol. Survey, i8th Ann.
Rept., pt. 5, pp. 1105--1168, 1897.)
Ries, Heinrich.
Feldspar and quartz. (U. S. Geol. Survey, i8th Ann. Rept, pt. 5,
pp. 1365-1368, 1897.)
Ries, Heinrich.
Physical tests of New York shales. (School of Mines Quarterly,
vol. 19, pp. 192-194, Jan. 1898.)
Salisbury, R. D.
The physical geography of New Jersey. With appendix by C. C.
Vermeule. (Geol. Survey New Jersey, Final Rept., vol. 4, xvi, 170 and
200 pp., 24 pis., I map, 1898.)
Spencer, J. W.
The West Indian bridge between North and South America. (Ap-
pletons' Pop. Sci. Monthly, vol. 53, pp. 10-30, May 1898. )
Swank, J. M.
Iron and steel and allied industries in all countries. (U. S. Geol.
Survey, i8th Ann. Rept., pt. 5, pp. Si-HO, 1897.)
Tassin, Wirt.
The mineralogical collections in the U. S. National Museum. (U.
S. Nat. Museum, Rept. for 1895, pp. 995-1000, pi. i, 1897.)
Correspondence, 393
Turner, H. W.
Classification of igneous rocks. (Science, new ser., vol. 7, pp.
622-625, May 6, 1898.)
Tyrrell, J. B.
The Cretaceous of Athabasca river. (Ottawa Naturalist, vol. 12,
pp. 37-41, May 1898.)
Upham, Warren.
The parallel roads of Glen Roy. (Am. GeoL, vol. 21, pp. 294-300,
May 1898.)
Veatch, A. C.
Notes on the Ohio valley in southern Indiana. (Jour. Geol,, vol.
6, pp. 257-272, Apr.-May 1898.)
Vermeule, C. C.
Notes and data pertaining to the physical geography of the state
[New Jersey]. (Geol. Survey New Jersey, Final Kept., vol. 4, appen-
dix, 200 pp., pi. 15, 1898.)
Wagenen, T. F. Van.
System in the location of mining districts. (School of Mines Quar-
terly, vol. 19, pp. 189-192, Jan. 1898.)
Weller, Stuart.
Classification of the Mississippian series. (Jour. Geol., vol. 6, pp.
.303-314. Apr.-May 1898.)
Wharton, Joseph.v
Nickel and cobalt. (U. S. Geol. Survey, i8th Ann. Rept., pt. 5,
pp. 329-342, 1897.)
Winslow, Arthur.
A natural bridge in Utah. (Science, new ser., vol. 7, pp. 557-558,
Apr. 22, 1898.)
Woodward, A. S.
The history of the Mammalia in Europe and North America. (Nat-
ural Science, vol. 12, pp. 328-336, May 1898.)
CORRESPONDENCE.
On Mr. Frank Leverett's "Correlation of Moraines with
Beaches on the Border of Lake Erie." In the March issue of
this journal Mr. Leverett opens a correspondence on my paper en-
titled "An account of the researches relating to the Great lakes". He
says that "Dr. Spencer has intimated in the February American Geol-
ogist that these later studies have removed the supposed evidence of
ice occupancy of the eastern part of the region during the formation
of beaches in the western part, and that they sustain his cherished view
that the shore lines are marine." He further implies that I do not
394 ^'^^ American Geologist, june, 1888
regard the hypothesis of glacial dams as "a result of logical reasoning".
The doctrine in favor of glacial dams is certainly no stronger and no
more ably supported by distinguished opinions than was the question
of glacial excavation of lake basins, which my investigations, in spite
of the opposition at the time, have aidied in dispelling. The change of
opinion which has taken place in this great subject gives me confidence
in not accepting the hypothesis of glacial dams based upon evidence
which, although often plausible, recedes on being approached.
The first point in question is the hypothesis of the termination of
deserted beaches against moraines. To reiterate, there are three notable
examples where glacial dams have been theoretically located, namely
at North Adams, New York, at Crittenden, New York, and at Cleve-
land, Ohio. At both Crittenden and Cleveland Mr. Leverett announced
what he considered the termination of the beaches against moraines,
which, if the facts were correct, would become very strong evidence.
But in the case of North Adams I found the continuation of the Iro-
quois beach beyond that point, a fact since recognized by the author
of the dam. Prof. Gilbert. Mr. Leverett's conclusions as to the ter-
min:ition of the Forest beach at Crittenden have since been set aside
by Prof. Fairchild's discovery of its extension farther eastward without
finding its termination. Again, at Cleveland Mr. Upham found that
the beach extended beyond the morainic termination, and suggested
that it probably reached ten miles farther. Thus when beaches have not
been traced to their terminations against moraines, in the best known
localities where such phenomena have been described, and failed of
establishment, it seems illogical to cite such as a diagnosis of glacial
dams; — the more so as contradictory evidence is suggested in the ter-
races farther east. Although I recognize the important contributions
towards the final history of the Great lakes by those who use the
glacial dam as a working hypothesis, yet the evidence so far adduced
as to the location of the ice barriers themselves can only lead to the
verdict of "not proven".
In my paper referred to I have mentioned terraces upon the southern
side of the Adirondack mountains, — I may also add upon the southern
and eastern sides of the White and Green mountains,— as occurring
at hundreds of feet above the low lands, and having the same character-
istics as the terraces upon the northern side of the mountains, which
last have been regarded by some as originating in glacial dams. Al-
though the observations extend over hundreds of miles and are of as
much importance as the beaches about the western end of the lakes,
they have been left unexplained by the advocates of jcrlacial dams. Yet
for several years I have thrown down the challenge for their elucidation.
"Faith", says my critic, "in the harmony of the universe inspires con-
fidence that the features of debatable origin, in which Dr. Spencer has
taken refuge as a defense against glacial dams (page 117) and which
have as yet received less attention than they merit, will some time
be found consistent with the already well established facts and prin-
ciples of geology, among which facts it seems safe to include glacial
Correspondence. 395
dams". My faith in the uniformity of nature is not less strong tlian
that of Mr. Leverett, and for this very reason when he includes among
"established facts" glacial dams, based upon evidence which is found to
be elusive, and when he ignores phenomena which he says have received
less attention than they merit, although they are of fundamental im-
portance, one's reason compels him to halt before such a doctrine, and
to discredit the acceptance of an hypothesis against which such powerful
facts appear.
Another class of phenomena embraces the channels across divides,
frequently characterized by gravel floors, and where such are found
they have often been considered as evidences per se of the outlets of
glacial lakes. Against this interpretation I have already pointed out
that we find terraces of similar hight upon both the southern and
northern sides of the plateaus, — or outside and inside the glacial dams.
Furthermore phenomena exactly similar to the so-called outlets of
glacial lakes are seen at low altitudes within a few degrees of the
equator, as for example in the Tchuantepec isthmus in Mexico, an
illustration of which may be seen in the /accompanying figure. Upon
the Atlantic side there is an extensive gravel terrace corresponding to
Fig. 1. Norlt.Qrn pn.l tit channel or Bsologicttl canal over the Ti)huBnte[«c Uivi.ifl.
the gravel floor of the channel across the divide, which is an exact
reproduction of the so-called glacial lake outlets of the noith. This
geological canal is less than a mile long and a hundred and fifty feet
deep. Upon the Pacific side the descent is so rapid that the corre-
sponding terrace-like features have been washed away. The character-
istics of this channel over the divide are almost like those at Crawford
396 Tlu American Geologist* June, i89s
notch in the White mountains where the gravel terraces have been re-
moved from the immediate canon on the one side, but characterize the
other end of the notch. No one can associate this Tehuantepec canal
with glacial dams. So long as such features in the lake and mountain
regions are produced by other causes than the outflow of glacial dams
it seems quite logical to question the verity of such evidence in their
favor, especially when the elevated terraces on the southern side of
the highlands throughout a region of hundreds of miles in length in-
dicate open water where glacial dams should occur. Thus the great
volume of evidence that can be obtained through observations of these
classes of phenomena is very much more than a "refuge" in support
of the objections against the claimed establishment of the doctrine of
glacial dams, the location of which has proved, so far, indefinite.
The advocates of glacial dams have taken it upon themselves to
prove their late existence; — and when they have accurately located
them, brought the high terraces upon the southern and eastern sides
of the plateaus into harmony with their hypothesis, and established that
the present channels over divides are evidence per se of glacial dams; —
then we shall be ready to accept their hypothesis as the result of logical
induction. But until then the pronunciamento that glacial dams "seem
established facts and principles of geology" must be doubted by in-
dependent investigators.
Washington, D. C, March 24, i8g8, J. W. Spencer.
PERSONAL AND SCIENTIFIC NEWS.
The University of New Mexico, at Albuquerque, is to
have a practical summer school in geology and mining un-
der the charge of the president, C. L, Herrick. Two months
will be spent in topographical and geological work in the
Magdalene mountains. Arrangements have been made
whereby a limited number of students not members of the
University can attend this summer school.
The National Academy of Sciences held its annual
stated session in Washington on April 19th to 22nd. The
most interesting paper presented, from a geological stand-
point, was by Prof. Alexander Agassiz on *'The coral reefs
of Fiji." Other papers of interest to geologists were: ** Bio-
graphical memoir of E. D. Cope" by Theodore Gill; "New
classification of the Nautiloidea" by Alpheus Hyatt. No new
members of the Academy were elected, but a number of for-
eign associates were added, among whom are the geologists
Prof. Edward Suess, of Vienna, and Prof. Karl Alfred von
Zittel, of Munich. .
Personal and Sciefitific News. 397
The Academy of Sciences of St. Louis. Prof. Fred-
erick Starr, in Appletons' Popular Science Monthly for
March, gives the history and a sketch of the work of this
important, pioneer, western association. Several portraits
of prominent members of the Academy are given and
among these are the geologists B. F. Shumard and G. C.
Swallow.
Geological Society of Washington. At the meet-
ing of March 9th the following papers were presented:
The Mesozoic section Sierra Blanca, Texas. T. W. Stanton.
Tbe Belly River horizon on the upper Missouri river. F. H.
Knowlton.
Trachandesite flows of the Sierra Nevada. F. L. Ransome.
At the meeting of March 23rd the following papers were
presented:
Crystalline schists and rock flowaj?e. C. R. Van Hise.
Igneous phenomena in the Tintic mountains, Utah. G. C. Smith.
A "blow-out" near Mancos, Colorado. A. C. Spencer.
At the meeting of April 13th the following papers were
presented:
Geology of the McAlester quadrangle. J. A. Taff.
The probable age of the McAlester coal group. David White.
The Franklin and Nomini folios. N. H. Darton.
On the succession of the igneous rocks of the Sierra Nevada. H. W.
Turner.
At the meeting of April 27th the following papers were
presented:
Methods of obtaining geothermal data. N. H. Darton.
Volcanic rocks of the Piedmont region. Arthur Keith.
Mining geology of the Tintic mountains, Utah. G. W. Tower, Jr.
At the meeting of May nth the following papers were
presented:
Mountains of northern Montana. W. H. Weed.
The La Plata mountains, Colo. Whitman Cross.
M. Stanislas Meunier has begun a course of lectures in
experimental geology at the Paris Museum of Natural His-
tory. He discusses the various attempts that have been
made to reproduce geological phenomena artificially.
Mr. James P. Kimball, of New York City, will spend
the summer in surveying a belt of country in Montana be-
tween Red Lodge and the Yellowstone. His address will
be U. S. Assay Office, Helena, Montana.
Mr. Horace V. Winchell, of Minneapolis, has accepted
the position of geologist for the Anaconda Copper Mining
company at Butte, Montana.
New York Academy of Sciences. Section of Geology
and Mineralogy. April i8th, 1898.
The first paper of the evening was by Dr. A. A. Julien,
on "The Elements of Strength and Weakness in Building
Stones." Dr. lulien called attention to the fact that in the
39^ The American Geologist. June. 1888
testing of building stones little consideration is given to the
causes influencing their various properties. In judging the
resistance, which a stone shows towards weathering, care
should be taken to recognize the character of the forces to
which it has been subjected. The strength of a stone bears
no relation to its mineral components, but is dependent on the
shape and arrangement of the mineral grains and character
of the cementing material. In considering the strength of a
stone four facts have to be kept in mind, viz.: interlockment
of the particles; coherence, dependent on character of the ce-
ment and adhesion of the grains; rigidity; and tension.
The "quarry sap," Dr. JuHen believes, plays a more im-
portant role than has hitherto been recognized, as it probably
carries much of the cement in solution and deposits it only
when the stone is exposed to the air. This accounts for the
hardening of the stones after being quarried. A distinction
should also be made between porosity due to cavities between
the grains and that due to interstices in the individual miner-
als. The former is a source of weakness, the latter not, al-
though either may cause the rock to exhibit a high absorp-
tive capacity. All of these points which have an important
bearing on the strength of building stones are best studied
with the microscope. The paper was illustrated by means of
sections thrown on the screen with a polarizing lantern. Dis-
cussion was by Prof. Kemp and Mrs. Dudley.
The second paper of the evening was by J. D. Irving, on
"Contact-metamorphism of the Palisades Diabase." Mr.
Irving referred to the work done by Profs. Osann and An-
drae some years ago, and stated that his results agreed with
theirs, but recent railroad excavations at Shadyside had en-
abled him to obtain additional facts. The diabase flow be-
comes denser, finer grained and porphyritic towards the con-
tact, with a decrease in hypersthene. It is also conformable
with the Newark shales. In addition to the zones found by
Osann, Mr. Irving found: (i) a normal hornfels zone rich in
Spinel; (2) a hornfels zone with brown basaltic hornblende
layers; (3) hornfels with an undeterminable isotropic mineral
resembling leucite; (4) hornfels with andalusite, becoming ar-
kose farther from the contact. This diabase is to be consid-
ered as an intruded mass and not a surface flow. The paper
was discussed by Profs. Kemp and Dodge, Dr. Hovey and
Mr. White.
Heinrich Ries, Secretary.
INDEX TO VOL. XXI.
Academy of Sciences of St. Louis, 397.
Account of the Researches relatingr to
the Great Lakes, J. W. Spencer, 110.
Additional Note on the Oceanic Current
in the Utica Epocli, R. Ruederoann,7n.
Aftonian and Pre-Kansan Deposits in
Southwestern Iowa. H. Foster Bain,
255.
Affassiz. Alexander, 3:{t.
Alaska, Government Exploration in. 265.
Alaska, Reconnaissance of the Gold
Fields of Southern, G. F. Becker, 382.
American Association for tho Advance-
ment of Science, 331,
Anthracite Coal in Arizona, W. P. Blake.
345.
Archcan Character of tho Nucleus of tho
Antilles. Persifor Frazer, 25().
Archean of Minnesota and of Finland,
Some Resemblances between the, N. H.
Winchell, 222. ^ ^
AuiTUsta in Geology, Use of the Terra,
C. R. Keyos, 22«. ., ^ „
Australian Tertiary MoUusca, G. F.
Becker, :383.
Authors' Cntalc»gae, Monthly, 68, 131,
192,245. :i2.*,;<87.
BAckstrOm, Holge. VestAnafaltet: En
Petro^enetisk Studie, 385.
Bain, H. F., Drift in Southwestern
Minnesota and Northwestern Iowa,
136; Aftonian and Pre-Kannan Depos-
its in Southwestern Iowa, 255.
BHker, Marcus. :iiQ.
Batepville Sandstone of Arkansas, Stu-
art W«^ller, 129.
Becker, G. F., Reconnaissance of the
Gold Fields of Southern Alaska, 382;
Australian Tertiary MoUusca. 3»3.
Ben Nevis, the Last Stronghold of the
Britisli Ice-Sheet, Warren Upham, 375.
Berkev,C. P.. Geology of the St. Croix
Dalles, 139, 270.
Blake. W. P. Hi^; Anthracite Coal in
Arizona, 345.
Brigham. A. P., Note on Trellised Drain-
age in the Adirondacks, 219.
Broadhead, G. C, Sketch of Maj. Fred-
erick Hawn. 267.
Brodie, P. B.. 74.
Calvin. S.. 64 ; ;iH2; Interglacial Deposits
of Northwestern Iowa. 251.
Carbonirerou.-* Formations of Southwest-
ern l»)wa.C. R. Keyes, 346.
(•ase of Geological Parasitism, 123.
Catalogue of tlu* Tertiary MoUusca in
the D -partmont of (loologv, British
Mu!^enm, Pt. 1. TliH Australian Terti-
ary MoUusca. (i. F. Harris. 383.
Certain Resemblances between the Arch-
nan in Minnesota and in Finland, N. U.
WincheU, 136; 222.
Champlaiu Submergence in the Narra-
gansett Bay Region, M. L. Fuller, 310.
Clay and Kaolin Deposits of Europe,
HcinricbRies,266.
Clay pole, E. W., Paleolith and Neolith,
Coal'in Arizona, Anthracite, W. P. Blake,
315.
Contact Metamorphism of the Palisades
Diabase, J. D. Irving, 398.
Copper in Lake Superior Iron Mines, 331.
Correlation of Moraines with Beaches on
the Border of Lake Erie, Frank Lever-
ett, 199.
Correspondence .
The Mociianical Action of the Divining-
Rod, M. E. Wads worth, 72.
Zirkely te : A Question of Priority , M.
E. Wadsworth. 133.
Correlation of Moraines with Beaches
on the Border of Lake Erie, F. Lev-
en* tt. 199.
A New Well at Bock Island, Ills., J. A.
Udden, 199.
Archean Character of the Nucleus of
the Antilles, Persifor Frazer, 2.50.
The Interglacial Deposits of North-
eastern Iowa, Samuel Calvin, 251.
The Weathered Zone (Yarmouth) be-
tween the Illinoiau and Kansan Till
Sheets, Frank Leverett, 254.
The Weathered Zone (Sangamon) be-
tween the lowan Loess and Illinoian
Till Sheet. Frank Leverett, 2r)4.
The Aftonian and Pre-Kan^an Deposits
in Southwestern Iowa, H. F. Bain,
2.Vi.
Some Preglacial Soils. J. A. Udden, 262.
On the Formation of New Ravines,
Edwin Linton, 329.
On Mr. Frank Leverett's "Correlation
of Moraines with Beaches on the
Border of Lake Erie," J. W. Spencer,
393.
Cote Sans Dessein and Grand Tower, C.
F. Marbut. 86.
Cummins, Edgar R., 74.
Darton, N. H., Developments in Well
Boring and Irrigation in Eastern
South Dakota. :i25
Dav, D. T., Mineral Resources of the
United States, 189^. :^80.
Des Cloiseaux, .X., 332.
Determination of the Feldspars, N. H.
WiuchoU, 12.
Dodge, R. E.. Scientific Geography in
Education, 201.
Drainage in the Adirondacks, Note on
IrelUsed, A. P. Brigham, 219.
400
Index.
Drake, N. F., 134.
Drift, in Southwestern Minnesota and
Northwestern Iowa, H. F. Bain, 136.
Drumlins in Glasgow, Warren Upham,
23.>.
Elements of Strength and Wealcness io
Buildiug Stonet, A. A. Julion, 397.
Eirtman, A. H., Geology of the KewHena-
wau Area of Northeastern MinnesotH,
90, 175.
End of the Ice-Age in Minnesota, Warren
Upham, i:i6.
Feldspars, Determination of the, N. H.
WincheU, 12.
Field Notes in Now Mexico Geology, C.
L. Herricic, 1H6.
Fontaine, 50.
Formation of New RaTines. E. Linton,
3i9.
Fossils.
Triblidiura rectilaterale n. sp., 280.
Triblidium convexura, n. sp., 280.
Triblidium barabueiisis, 281.
Triblidium extensum, n. sp., 281,
Triblidium corpulentum, n. sp., 281.
Triblidium aduncum, n. sp., 282.
Hypseloconus, 2<«2.
Hypseloconus recurvus, var. elongatus,
n. var., 284.
Hypscloconas cornutiformis, n. sp,.
285.
HypHeloconus capuloides, n. sp., 285.
Hypseloconnsfranconiensis, n. sp.,285.
Hypseloconus cylindricus, n. sp., 285.
Hypseloconus stabilis, n. sp., 286.
Scaovogyra minnesotensis, n. sp., 286.
EuorapliHlns strongi.var. sinistrorsus,
n. var, 287.
Agraulus convexus, 288.
Agraulus hemispbericus. n. sp., 289.
Cheilocephalus, 289.
Choilocephalus st. croixensis, n. sp.,
i90.
Dicellocephalus misa, 290.
Australian Tertiary Mollusca, 383.
Fouqu6, 13.
Frazer, Porsifor, 68; Archean Character
of the Nucleus of the Antilles, 250.
Fuller, M. L., Champlain Submergence
in the Narragansett Bay Region, 310.
Further Notes on Block Island : geology
and botany, Arthur Hollick. 200.
Genesis of Iron Ores, Residual C^oncen-
tration by Weathering as a Mode of,
J. P. Kimball. 155.
Geological Section from Moscow to
Siberia and Return, Persifor Frazer,
68.
Geological Society of America, 135 ; 397.
Geological Society of Washington, 135;
201.
Geological Structure of Shantung, F. v.
Richthofen, :^1.
Geological Survey of Iowa, Samuel Cal-
vin, 64: 382.
Geological Survey of Maryland, 332.
Geological Survey of Now Jersey, J. C.
Smock. 126.
(reological Survey of the South African
Republic. 137.
Geology of Ma.ssanutten Mountain in
Virginia, A. C. Spencer, 191.
Geology of the Environs of Tammerfors.
J. J. Sedcrholm, 213.
Geology of the keweenawau Area in
Northeastern Minnesota, A. H. Elft-
man, 90, l7.^.
Geology of the St. Croix Dalles, C. P.
Berkey, 1:^,270.
Geology of the Vicinity of Greater New
York, F.J. H. MerrUl, 72.
Gilbert, G. K., Sketch of Jos. F. James,
1.
Government Exploration in Alaska, 26.5.
Grant, U. S., Relations of the Saganaga
Granite to the Surrounding Rocks, IXKl.
Great Lakes. Account of the Researches
relating U-t the, J. W. SpHncor, 110.
Guano Deposits of the Islands in the
Southern Pacific, J. J. Riley. 73.
>se do Paris et des uun6raux qui
l*accompag«'nt, A. Lacroix, 244.
H
Gyps
Harker, Alfred, Petrology for Students,
67.
Haughton, Samuel, 74.
Hawn, Major Frederick, G. C. Broad-
bead, 267.
Herrick, C. L., Field Notes in New Mex-
ico Geology, 136.
Hollick, A., Recent Explorations for
Prehistoric Implements in the Trenton
Gravels, Trenton, N. J., 135; Further
Notes on Block Island, 200.
Hohn, Gerhard, Paleeontologiska Noti-
ser, 188.
Hornblende, occurring in a Hornblende
Gabbrofrom Pavone, near Ivrua, Pied-
mont, Italy, Studies on an Interesting,
F. R. VanHorn, :<70.
Hubbard, G. G., 74.
I
Indiana Academy of Science, 138.
Institute of France, Cuvier Prize, 74,
Interglacial Deposits of Northwestern
Iowa, Samuel Calvin, 251.
Iowa Academy of Science, 74.
Iowa Geological Survey. Administrative
Reports, 382.
Iron Meteorites. 331.
Irving, J.J).. Contact-metamorphism of
the Palisades Diabase, 398.
Jaggar, T. A., An Occurrence of Acid
Pegmatyto in Diabase, 203.
James, Jos. F.. G. K. Gilbert, 1.
Juliun, A. A., Elements of Strength and
Weakness in Building Stones, 397.
K
Kalgoorlite— A New Telluride Mineral
from Western Australia, E. F. Pittman,
3s3.
Kayser, E., BeitrAge zur Kenntniss em-
iger palBPOzoischer Faunon Sud-.\meri-
kas 66.
Kemp, J. F., Some Eruptive Rocks from
the Black Hills, 135.
Keweenawan Area of Northoastem Min-
nesota, Geology of, A. H. Elftman, 90,
175.
Kovcs, C. R., Use of the Term Augusta in
Geology, 229; Carboniferous Forma-
tions of Southwestern Iowa, 346.
bidex.
401
Kimball, J. P., 307 ; Residual Coocentra-
tioo by Weathering as a Mode of Gen-
esis or Iron Ores, IM.
Knight, WUburC..'i2Ul.
Lacroix, A., 13; Le Gypse de Paris et les
miu6raux qui 1* acccompagnent, 244.
Leverett, Frank, Correlation of Moraines
with Beaches on the Border of Lake
Erie, 195 ; Weathered Zone (Yarmouth)
between the lllinoian and Kansan Till
Sheets, 254; Weathered Zone (Sanga-
mon) between the lowan Loess and
lllinoian Till Sheet, 254 ; Water Besour-
ces of Indiana and Ohio, 324.
Leverett's "Correlation of Moraines with
Beaches on the Border of Lake Erie,"
J. W. Spencer, 383.
Lindgren, Waldemar, 74.
Linton, £., On the Formation of New
Bavines, 32U.
Lonsdale, £.H.,2&4.
M
Magellan Territories, Tertiary and Qua-
ternary Deposits in the, O. Nordensk-
jold, 3(10.
Marbut, C. F., Cote Sans Desseiu and
Grand Tower, 86.
Marcou, Jules, 3:^2.
Marsh, O. C. 74.
Marsh Paleon tological Collections, 137.
Maryland Geological Survey, 3;i2.
Matthew. W. D., Revision of the Puerco
Fauna, 190.
Morrill, F. J. H., 72.
Meteorite, A New, 73.
Meteorites, Iron and Stone. 331.
Meuuior, Stanislas, 397.
Michel- L6vy, 13.
Millor, S. A..i:^.
Milne. John, 2i)2.
MiNEBAIjS.
Feldspars, determination of the, 12.
Coal. Pittsburg Bed, 49.
Py rite, 149 ; Quartz, 149 ; Magnetite, 149 ;
Hematite, 150; Calcite, IJW; Traver-
tine, 150; Malachite,150; Azurite, 151 ;
Orthoclase, 151; Labradorite. 151;
Augite, 151 ; Hornblende, 151 ; Actin-
olite, 151; Muscovite, 151; Biotite,
152; Epidote, 152; Olivine, 152: Chlo-
rite, 152; Glauconite, 152; Kaolin,
i.'tS: Apatite. IISS.
Hornblende. 370.
Kalgoorlite. :«3.
Mineral Resources of the United States.
1896, D. T. Day, 380.
Minnesota Academy of Natural Sciences,
i:».
Monthly Authors' Catalogue, 68, 131, 192,
245,325,387.
N
National Academy of Sciences, 396.
New Developments in Well Boring and
Irrigation in Eastern South Dakota,
N. H. Darton, 325.
New York .\cadomy of Sciences, 72, 135,
200, 266. 397.
New Well at Rock Island, Ills., J. A. Ud-
den, 199.
Norden»kjold. O.. Tertiary and Quater-
nary Deposits in the Magellan Territo-
ries, 300.
Note on Trellised Drainage in the Adi-
rondacks, A. P. Brlgham, 219.
Occurrence of Acid Pegmatyte in Dia-
base, T. A. Jaggar, Jr., 203.
Oceanic Current in the Utica Epoch, Ad-
ditional Note on the, R. Ruedemann,
75.
On the Formation of New Ravines, E.
Linton, 329.
P
Pselfeozoiseher Faunen Sud-Amerikas,
E. Kayser, 66.
Paleeontologiska Notiser, Gerhard Holm.
188
Paleolith and Neolith, £. W. Claypole,
333.
Parallel Roads of Glen Roy, Warren Up-
bam, 294.
Pegmatyte in Diabase, An Occurrence of
Acid, T. A. Jaggar, Jr., 2U3.
Peneplain, K. S. Tarr, :^1.
Petrology for Students. Alfred Harker,
67.
Pittman, E. F., Kalgoorlite— a New Tell-
uride Mineral from Western Australia,
383.
Pittsburg Coal Bed. I. C. White, 49.
Popocatapetl and Orizaba, 332.
Recent Explorations for Prehistoric Im-
plements in the Trenton Gravels, Tren-
ton, N. J., Arthur Holiick, 135.
Reconnaissance of the Gold Fields of
Southern Alaska, G. F. iiecker, 382.
Relations of the Saganaga Granite to
the Surrounding Hocks, U. S. Grant,
137.
Report on the Doobaunt, Kazan and Fer-
guson Rivers, and the Northwest Coast
of Hudson Bay, J. B. Tyrrell, 128.
Residual Concentration by Weathering
as a Mode of Genesis of Iron Ores, J. P.
Kimball, 155.
Revision of the Puerco Fauna, W\ D.
Matthew, IbO.
Richthofen, F. v.. Geological Structure
of Shantung, China, 321.
Ries, Heinrich, The Clay and Kaolin De-
eosits of Europe, 226.
ey, J. J., Guano Deposits of the
Islands of the Southern Paciiic, 73.
Roe, A. D..202.
Ruedemann, R., Additional Note on the
Oceanic Current in the Utica Epoch, 75.
Russell, I. C, Volcanoes of North Amer-
ica, 65.
Russian Province of Kursk, 331.
Science Series, 202.
Scientific Geography in Education, R.
E. Dodge, 201.
Sederholm, J. J., The Geology of the En-
virons of Tammerfors, 2i3.
Shell-bearing Drift on Moel Tryfau.
W^arren Upham, 81.
Significance of the Fragmental Eruptive
Debris at Taylor's Falls, N. H. Win-
chell, 136.
Smock, J. C, 126.
Soci6t6 Geologique de Bolgique, ^^30.
Some Eruptive Rocks from the Black
Hills, J. F. Kemp, 135.
Some Preglacial Soils, J. A. Udden, 262.
Some Resemblances between the kx-
chean of Minnesota and Finland, N.
H. Winchell, 222.
402
Index,
Spencer, A. C, Gteolo^y of Massaautten
Mountain in Virginia, 191.
Spencer, J. W., An Acconnt of the Re-
searches relating to the Great Lakes,
110: On Mr. Frank Leverett's "Correla-
tion of Moraines with Beaches on
the Border of Lake Erie," 3d3.
Spurr, J.E., 202.
Studies on an Interesting Hornblende
occurring in a Hornblende Gabbro,
from Pavone, near Ivrea, Italy, F. R.
Van Horn, 370.
T
Tarr^ R. S., The Peneplain. 351.
Tertiary and Quaternary Deposits in the
Magellan Territories. O. Norden-
skjold, 300.
Tyrrell, J. B., Report on the Doobaunt,
Kazan and Ferguson Rivers, and the
Northwest Coast of Hudson Bay, 128.
U
Udden, J. A., A New Well at Rock Island,
Ills.. 199; Some Pre^lacial Soils, 262.
United States Geological Survey, C. D.
Walcott, 61.
University of New Mexico. 396.
Upham, Warren, Shell-Bearing Drift on
MoelTryfan.81; The End of the Ice-
A^e in Minnesota, 136; Valley Mor-
aines and Drumlins in the English
Lake District, 165 ; Drumlins in Glas-
gow. 235 ; The Parallel Roads of Glen
Boy, 294 : Ben Nevis, the Last Strong-
hold of the British Ice-Sheet, 375.
Use of the Term Augusta in Geology, C.
R. Keyes. 229.
Valley Moraines and Drumlins in the
English Lake District, Warren Upham,
165.
Van Horn, F. R., Studies on an Interest-
ing Hornblende occurring in a Horn-
blende Gabbro, from Pavone, near
Ivrea, Piedmont, Italy, 370.
Vest&naf altet : En Petrogenetisk Stadie,
H. BackstrOm, 385.
Volcanoes of North America, I. C. Rus-
sell, 65.
W
Wadsworth,M. E.,The Mechanical Ac-
tion of the Divining Rod, 72 ; Zirkel-
yte : A Question of Priority, 134 ; Some
Methods of Determining the Positive
or Negative Character of Mineral
Plates, 170.
Walcott, C. D., 61.
Water Resources of Indiana and Ohio,
Frank Leverett. 324.
Weathered Zone (Sangamon) between
the lowan Loess and Illinoian Till
Sheets, Frank Leverett, 254.
Weathered Zone (Yarmouth) between
the Illinoian and Kansan Till Sheets,
Frank Leverett, 254.
Weller, Stuart, Batesville Sandstone of
Arkansas, 129.
White, I. C. Pittsburg Coal Bed, 49.
Winchell, H. V., 397.
Winchell, N. H., 134; Determination of
the Feldspars, 12 ; Significance of the
Fragmental Eruptive Debri.s at Tay-
lor's Falls, 136 ; Certain Resemblances
between the Archean in Minnesota and
in Finland. 136,222.
Zirkelyte: A Question of Priority, M. E.
Wadsworth, 133.
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