Chapter IV: Part 4

Accurate measurements of the vertical intervals between well defined beaches at many localities would enable one to identify special horizons, providing orographic movements were not in progress during the time the series was forming. This method has recently been successfully applied on the north shore of Lake Superior, where the character of the country does not admit of the tracing of individual terraces for considerable distances.

The deltas of tributary streams should also be revealed in the topography of the basin of an ancient water body. Changes in the character of lacustral sediments near where rivers emptied are also to be looked for. Sand dunes are frequently an important accompaniment of existing shores, and their association, perhaps, in a modified form, with ancient beaches is to be expected.

5. _Fossils._ Thus far only a few fossils have been found in the stratified clays and sands or in the ancient beaches of the Laurentian basin. Such observations as have been made in this connection indicate an absence of the remains of marine life and the presence, in a few instances, of fresh-water shells in all of the basin west of the eastern border of the basin of Lake Ontario. To the eastward of Lake Ontario, however, in the St. Lawrence and Champlain valleys, marine fossils are common in deposits supposed to be contemporaneous with the stratified clays to the west.

A careful search in the clays and beaches left by the former water bodies might be rewarded by important discoveries. In this examination microscopical organisms should not be neglected. If after a detailed examination no fossils are discovered, this negative evidence would have its value, as it would indicate that the physical conditions were not favorable to life, and an explanation for this fact might be found. It is scarcely necessary to mention that care should be taken not to mistake the shells occurring in modern swamp deposits associated with the ancient beaches for true lacustral fossils.

About the borders of the present lakes and sometimes even below the level of the lowest of the ancient beaches the remains of the mastodon, elephant, giant beaver, elk, bison, deer, etc., have been found. The recency of the existence of such of these animals as are extinct may thus be established, as well as the former distribution of those still living in other regions.

Evidence of the existence of man has been reported from one of the old lake ridges in New York, and it is important that this interesting discovery should be sustained by evidence from other localities. Stone implements especially should be looked for in undisturbed lacustral clays, and in the gravels of the ancient beaches.

The remains of forests have been stated to occur in the lacustral clays adjacent to the south shore of Lake Erie. It is desirable to know the extent of these deposits and how continuous they are; also the character of the plant remains they contain, and whether they have been disturbed from the position in which they grew. Some of the questions that may be asked in this connection are: Was the basin drained and forest covered before the vegetable remains were buried, or were the plants floated to their present position, or did they grow on moraines covering the stagnant border of the retreating glacier and become involved and buried in morainal material as the ice melted?

6. _Life in the present lakes._ The fauna of the present lakes has a bearing on their past history, for the reason that in the deeper parts of lakes Superior and Michigan crustaceans and fishes have been found which are believed to be identical with marine forms. These may be considered as “living fossils,” and are thought by some to indicate that the lakes in which they occur were formerly in direct communication with the ocean. If the occurrence of living marine species in the present lakes is found to be widely at variance with the history of the basin as determined from physical evidence, an inquiry should be made in reference to the manner in which the species discovered might migrate.

7. _Changes in elevation._ One of the most difficult problems in connection with the history of an inland region is the determination of changes of level. By leveling along an ancient beach, post-lacustral changes in the relative elevations of various points may be readily ascertained. Pre-lacustral changes, however, by which ancient valleys have been obstructed, are much more difficult of direct observation, but might appear from the study of the hard-rock topography, as has already been suggested. This branch of the investigation, however, should more properly begin at the coast and be extended inland.

8. _Former outlets._ Several localities where the waters of the Laurentian basin have overflowed during former high-water stages have been pointed out, but some confusion has arisen in this connection, for the reason that the channels formed by streams issuing from the margin of the ice during the closing stages of the Glacial epoch have, in some instances, been mistaken for evidence of former lake outlets. The old outlets which seem to have been well determined are situated at different levels, and show that the entire basin could not have been occupied by a single great water-body, unless, as has been supposed by some, it was in direct communication with the sea. This hypothesis will be considered below. It has sometimes been assumed that all of the basin below the level of some ancient outlet was once flooded, so as to form a great lake in all of the basin now situated at a lower level; but, in making such generalizations, the possibility of places in the rim of the basin being at a lower level than the outlet discovered, thus necessitating a special explanation, such as the partial occupation of the basin by glacial ice, or changes in elevation of such a character as to raise the locality of former overflow or to depress other regions, have to be considered.

Former outlets should bear a definite relation to neighboring shore lines and to sedimentary deposits. The channels leading from former points of discharge merit examination, as here again changes of level may perhaps be detected in the gradients of stream terraces.

Most of the ancient outlets thus far recognized lead southward, but as previously mentioned, a former channel of discharge north of Lake Superior has recently been reported. If this observation is confirmed, it will have an important bearing on questions relating to changes of level and to the position of the ice front during the later stages in the retreat of the glaciers.

9. _Probable effects of a retreating ice sheet on drainage._ The generally accepted conclusion that glaciers advanced southward and occupied the Laurentian basin during the Glacial epoch and retreated northward toward the close of that epoch, is sustained by a vast body of evidence. As the ice sheet withdrew it left a superficial deposit frequently one or two hundred feet thick over nearly all of the region it abandoned, and pre-glacial drainage lines were obstructed and mostly obliterated. As long as the slope in front of the ice was southward, the drainage from it found ready means of escape, but when the slope was northward towards the ice front, the drainage was obstructed and lakes were formed.

We have good reasons for believing that the topography of the Laurentian region was essentially the same at the close of the Glacial epoch as it is now, but the broader question of continental elevation is less definite. The inequalities of the surface being essentially as we now find them, it would follow that the first lake formed when the ice retreated to the north of the divide running through central Ohio and central New York, would be small and dependent on minor features in the relief of the land, and would discharge southward. As the ice retreated, the lakes would expand and become united one with another and the larger lakes thus formed would still find outlet across the southern rim of the basin. As the glaciers continued to retreat lower and lower, passes would become free of ice and the lakes would be drained at lower levels, old beaches would be abandoned, the lakes would contract, and finally separate lakes would be formed in the lowest depression in the basins of the more ancient water bodies. The shape of the retreating ice front would be determined by topographic conditions and would in turn determine the northern outline of the lakes along its margin. This in brief is one hypothesis that has been proposed to explain the varied history recorded by the shore records, sediments, etc., within the basin.

10. _Communication with the sea._ Another hypothesis which assumes to account for some of the facts observed, is that the continent was depressed at the close of the Glacial epoch sufficiently to allow the sea to have access to the Laurentian basin. This hypothesis is coupled with others which do not recognize a period of Pleistocene glaciation, but, as already suggested, this is a matter that is considered by the great body of American geologists as not being any longer open to profitable discussion.

In the study here outlined the question whether the water bodies which formerly occupied the Laurentian basin were lakes or arms of the sea, should not be difficult of direct and positive determination. If fossils can be found within the basin, they might yield definite testimony, but even if they are absent or if their evidence is inconclusive, topography can be appealed to with the expectation of receiving a conclusive decision.

If the Laurentian basin was occupied by an arm of the sea during various stages in the Pleistocene elevation, then the records of such a submergence should occur both within and without the depression, and direct connection between the two should be expected. If the waters within the basin were capable of making such well-defined shore records as are now found, we are justified in assuming that the true ocean beach on the outer slopes of the basin would be still more conspicuous. Again, the waters within the basin deposited a sheet of sediment, certainly not less than one hundred feet thick; to be sure the conditions for rapid accumulation were there present, but if the ocean covered the adjacent land it should have left similar deposits. This is abundantly proven in the St. Lawrence and Champlain valleys, where clays containing marine fossils occur up to a certain horizon and record a Pleistocene invasion of these depressions by the sea. If the adjacent Ontario basin was occupied by the sea about the same time that the Champlain valley received its filling of clays containing marine fossils, there is every reason to believe that the deposits and their contained fossils in each basin would have been essentially the same.

One of the best known of the ancient shore lines about Lake Ontario has an average elevation of approximately 500 feet above the sea. If the sea had access to the basin at the time this breech was formed, then at corresponding horizon without the basin especially, to the south and southeast, where the full force of the Atlantic’s waves would have been felt, there should be still more prominent beaches.

Many well-defined shore lines in the Laurentian basin are much higher than the one just referred to, and if these were also formed during various stages of submergence, as has been claimed, it is evident that ocean beaches and ocean sediments of Pleistocene age should be looked for over nearly the whole of the eastern part of the United States. The student may easily answer this question for himself, and thus perhaps make a contribution to the subject here treated.

In the investigation here outlined, the work of previous observers should not be ignored, and every plausible hypothesis that has been advanced to account for the facts observed should be carefully tested. In writing these pages I have not quoted the writing of others, for the reason that a discussion of evidence has not been the aim in view, and also because the writings examined are so numerous that justice could not be done them in the space at command. That the literature relating to the subject is voluminous is indicated by the fact that an annotated bibliography of the Pleistocene history of the Laurentian basin, now in preparation, already contains over 200 entries of individual papers.

ISRAEL C. RUSSELL.

FOOTNOTES

[52] The Topographic Features of Lake Shores, by G. K. Gilbert, in
Fifth Ann. Rep. U. S. Geological Survey 1883–4.

[53] Preliminary Paper on the Terminal Moraine of the Second Glacial
Epoch, by T. C. Chamberlin, in Third Ann. Rep. U. S. Geological
Survey, 1881–2.

_EDITORIALS._

The Summer meeting of the Geological Society of America will be held at Madison, Wis., on August 15 and 16. The session of the American Association for the Advancement of Science will begin at the same place on the 17th of August and extend to the 23d. The Congress of Geologists, under the auspices of the Columbian Exposition, will begin at Chicago, on August 24, and continue its sessions so long as its work may require. Preliminary to this series of meetings, Professors M. E. Wadsworth and C. R. Van Hise will meet such geologists as care to visit the Lake Superior region at the Commercial Hotel, Iron Mountain, Mich., on the forenoon of August 7, and will act as guides during the week following. A carefully prepared scheme for the trip is announced, embracing visits to the leading points of interest in the Menominee, Marquette and Gogebic iron districts, and in the copper-bearing region of Keweenaw Point. Those who desire to participate in the excursion, or who wish information regarding it, should address Professor Van Hise, at Madison.

In connection with the meetings of the Geological Society and the American Association at Madison, there will be excursions to the Devil’s Lake region, to the Dells of the Wisconsin, and to the driftless area, under the guidance of geologists personally familiar with the features of most special interest. The article of Professor Van Hise in this number is a timely presentation of some points of peculiar significance in the first named region, and will prove very serviceable to those who choose the excursion to that region.

It is proposed to hold the sessions of the Congress at Chicago at the Art Institute during the forenoons, leaving the afternoons free for visiting the Exposition. Experience has shown that a half day devoted to looking at exhibits, where there is such a plethora of objects of interest as in the Exposition, taxes the faculties of observation to the full extent of their pleasurable employment. Attendance upon the Congress and the study of the Exposition will, therefore, it is thought, constitute agreeable and profitable complements of each other. Excursions to points of geological interest in the vicinity of Chicago will be privately arranged, if desired.

These three meetings, with the attending excursions and the study of the Exposition, constitute a rare combination of opportunities which will doubtless be embraced very generally by the geologists of the country.

T. C. C.

*.*

The supply of numbers one and two of this JOURNAL remaining in the hands of the publishers has become reduced below the limit they desire to preserve for binding and for special purposes, and they would esteem it a great favor on the part of those who may have received duplicates, as sample copies or by the accidents of mailing while the lists were imperfect, if they would return such duplicates to them. They will gladly return the postage if the address of the sender is placed on the wrapper.

_REVIEWS._

CRYSTALLINE ROCKS FROM THE ANDES.

_Untersuchungen an altkrystallinen Schiefergesteinen aus dem Gebiete
der argentinischen Republik_ von B. KÜHN. Neues Jahrbuch für
Min., etc., Beit. Bd. VII., 1891, p. 295.

_Untersuchung argentinischer Pegmatite, etc._, von P. SABERSKY, _ib._
p. 359.

_Untersuchungen an argentinischen Graniten, etc._, von J. ROMBERG,
_ib._, VIII., 1892, p. 275.

Travelers and foreign residents in South America are rapidly furnishing information relative, not only to the volcanic, but also to the older crystalline rocks composing the great Andes chain. Since the early observations of Darwin,[54] the petrographical collections made by Stelzner during his three years’ residence, as professor, at Cordova (1873–1876) have been described by himself[55] and Franke,[56] while the results of detailed studies of the more extensive collections gathered by Stelzner’s successor, Professor L. Brackebusch, are now beginning to appear. Professor Brackebusch’s residence in the Argentine Republic lasted from 1876 till 1883, and during this period he made numerous scientific expeditions.[57] The petrographical material thus obtained has been confided to specialists in Germany for study. Three papers dealing with the crystalline schists (gneisses),[58] pegmatites,[59] and granites,[60] have recently appeared. The rocks of the granite contact-zones had been placed in Professor Lessen’s hands before his death, while communications on other special groups are doubtless to be expected.

These investigations naturally suffer from the forced absence of all field observations on the part of their authors, but the purely petrographical study of the material brings to light many points of interest, while it furnishes the only sort of detailed information regarding the rocks of these remote regions which we can for the present hope for. It is here desired only to direct attention to a few of the most striking results obtained from the Brackebusch material by the three authors last cited.

Dr. Kühn’s paper on the crystalline schists treats principally of gneiss, and offers little that is new. It is mostly occupied with additional evidence of structural and chemical changes due to dynamic metamorphism in the sense of Lehmann. The most noteworthy of these are development and microstructure of fibrolite; production of augen-gneiss from porphyritic granite; development of microcline structure in orthoclase by pressure; secondary origin of microcline, microperthite and micropegmatite; alteration of garnet to biotite and hornblende.

Dr. Sabersky’s paper on the coarse-grained granites or pegmatites is entirely mineralogical, and is devoted principally to elucidating the structure of microcline. The author concludes that the well-known gridiron structure is due, not to two twinning laws (the Albite and Pericline), as has been generally supposed, but to the Albite law alone, in accordance with which the individuals form both contact and penetration twins, like the albite crystals from Roc-tourné, described by G. Rose.

Dr. Romberg’s paper on the Argentine granites is much more extensive than the two preceding. It is embellished by seventy-two microphotographs, many of which admirably illustrate the special points described. He comes to several results of great petrographical significance, the most important of which relate to the origin of quartz-feldspar intergrowths in granitic rocks. He clearly shows that beside the original granite quartz there is also much of a secondary nature present. This is not microscopically distinguishable from the original mineral, but its later genesis is demonstrated by many careful observations on its relation to other constituents. The abundant secondary quartz is regarded as the product of weathering--principally of the feldspar, into which it has a peculiar tendency to penetrate. The extreme sensitiveness of quartz to pressure is emphasized (as it has been by Lehmann and the present writer) and illustrated by undulatory extinction, banding, granulation and even plastic bending around other minerals. Dynamic action is regarded as the efficient cause of the secondary impregnation of feldspar by quartz, and a union of this with weathering of the feldspar as the source of the abundant and complex pegmatitic intergrowths of quartz and feldspar.

These results are important, and they will now doubtless come to be generally recognized. It is, however, of interest to observe in this connection that all which is here announced as new in regard to secondary and “corrosion” quartz was described and figured in even greater detail by Prof. R. D. Irving ten years ago. This does not appear to be known to Dr. Romberg, for he does not allude to it, but anyone who will turn to pages 99 to 124 and plates XIII, XIV and XV of the monograph on the Lake Superior Copper Rocks (vol. 5, U. S. Geol. Survey, Washington, 1883) will find his conclusions stated in almost the same language and with a much wider range of fact and illustration. Dynamic action is not here adduced as a cause for the saturation of feldspar by secondary micropegmatitic quartz, since the Lake Superior rocks show no evidence of having been subjected to pressure, but that the quartz itself has been derived from the leaching of the feldspar substance and that the impregnation is mostly confined to the orthoclase is clearly stated.

Dr. Romberg also demonstrates, in a number of cases, the secondary origin of albite, especially as microperthite, and of microcline. He gives details relating to each of the mineral constituents, and then the effects of pressure and of chemical action on the most important of them. Among many interesting observations but a few can be even mentioned here; such, for instance, as the original character of muscovite in many granites; the alteration of garnet into muscovite; the dependence of the well-known pleochroic halos in biotite and cordierite upon the substance of the zircon which they almost invariably surround, and secondary rutile needles which grow out from biotite into both quartz and feldspar. In one rock occurring in a granite a violet, strongly pleochroic mineral was found, which, in neither composition nor physical properties, agreed exactly with any known species. It seems to be intermediate between andalusite and dumortierite, but, as its individuality is not yet perfectly established, no new name is proposed for it.

G. H. WILLIAMS.

_The Mineral Industry, its Statistics, Technology and Trade, in the
United States and Other Countries, from the Earliest Times to the
End of 1892._ Vol. I. Edited by RICHARD P. ROTHWELL, editor of
the _Engineering and Mining Journal_. 629 pp., 8vo.

This volume is a statistical supplement of the _Engineering and Mining Journal_, and is published by the Scientific Publishing Co., of New York, 1893. It takes the place of the former annual statistical number of the _Engineering and Mining Journal_, and it is the first volume of a series which is to be issued annually. The object of the present volume is to make known, as soon as possible after the expiration of the year 1892, the statistics and the various conditions of the mining industry in that year and in previous years. The future volumes will, each year, bring these statistics up to date, and thus the full particulars of the mining industry will be known within a few days of the expiration of every year. The volume is a compilation of articles written by different authors, and the names of these writers are guarantee that the different subjects have been treated by authorities in the departments with which they deal. The editor himself, it is but justice to him to state, has written some of the most important parts of the volume, notably the article on the statistics of gold and silver, and his well-known familiarity with the subjects he discusses renders the reader confident of their accuracy.

The present volume is not confined to the bare presentation of figures of production and consumption of various mineral products, but it treats each individual branch of the mining industry in its various departments; and in this way the volume really represents a series of treatises on the various mining products and the methods of treating them. The production of each material is given not only for the United States but also for foreign countries; the conditions of the American and foreign markets during 1892 and previous years are discussed, while the various uses of the different materials, the history of mining in different districts, the means of transportation, the metallurgical methods of treating different ores, the methods of sampling, and the possibilities of competition in various mining industries are also described. In addition to this, tables of assessments levied and dividends paid by various mining companies are given. The volume ends with a concise statement of the statistics and condition, as well as the extent, of the mining industries of foreign countries. Thus there is presented, in a volume of no excessive size, a complete and concise epitome of the mining industries of the world; and this work was completed almost immediately after the time to which it relates.

The various subjects are treated in the following order: A résumé and tables of statistics of the mineral products of the United States; articles on Aluminum, Antimony, Asbestos, Asphaltum, Barytes, Bauxite, Borax, Bromine, Cement, Chemical Industry, Chromium, Coal and Coke, Copper, Corundum and Emery, Cryolite, Feldspar, Fluorspar, Gold and Silver, Iron and Steel, Lead, Manganese, Mica, Nickel and Cobalt, Onyx, Petroleum, Phosphate Rock, Platinum Group of Metals, Plumbago, Precious Stones, Pyrites, Quicksilver, Salt, Soda, Sulphur, Talc, Tin, Whetstones and Novaculite, Zinc; Tables of Assessments Levied by Mining Companies from 1887–1893; Tables of Dividends Paid by American Mining Companies; Baltimore Mining Stock Market, Boston Mining Stock Market, Denver Mining Stock Market, London Mining Stock Market, Lake Superior Mining Stock Market, New York Mining Stock Market, Paris Mining Stock Market, Pittsburg Mining Stock Market, Salt Lake City Mining Stock Market in 1892, San Francisco Mining Stock Market; Foreign Countries--Austria-Hungary, Belgium, Canada, China, France, Germany, Italy, Japan, Russia, South American Countries, Spain and Cuba, Sweden, United Kingdom of Great Britain and Ireland.

The importance of the subject treated in this volume can be appreciated when it is known that the products of the mines of the United States alone in the census year of 1889 amounted to $587,230,662, and that this amount really only represents the interest on an immensely larger capital invested. The mining products of the United States are far more important in their aggregate value than those of any other country in the world, though, in many individual products, other countries supply more than the United States. This country is first, however, in the production of pig iron and steel. It is also first in the production of copper, gold, silver, petroleum, and a number of other products. Great Britain is still the leader in the production of coal, but the United States’ production is rapidly growing and already equals 81.08% of the British production, and supplies 28.75% of the world’s consumption.

Every subject in this volume is fully discussed, and at the same time nothing is given which is not appropriate and even necessary. Thus a combination of completeness and conciseness is reached which is excellent. Among the most carefully and exhaustively treated subjects are copper, gold and silver, the platinum group of metals and coal and iron, though many others might be mentioned, for every subject undertaken has been thoroughly treated. In the article on copper the statistics of production and consumption, as well as the condition of the various domestic and foreign markets, are fully discussed by the editor, and, in addition, separate articles are also given on “American Methods of Ore Sampling and Assaying,” by Albert R. Ledoux, and on “Bessemerizing Copper Matte,” by Charles Wade Stickney. The article on the statistics of gold and silver is by Mr. R. P. Rothwell, editor of the volume, and is an excellent piece of statistical work, giving, as it does, the statistics of production of gold and silver in the world for a number of years back. To this article are appended interesting papers on the “Chronology of the Gold and Silver Industry, 1492–1892,” by Walker Renton Ingalls, on “Recent Improvements in Gold Chlorination,” by John E. Rothwell, and on the “Cyanide Process,” by Louis Janin, Jr.

The article on the Platinum Group of Metals, by Charles Bullman, gives complete information regarding the production, consumption, nature of the deposits, metallurgy and uses of platinum and its related metals, iridium, rhodium, osmium, palladium and ruthenium. The articles on Coal and Coke and on Iron and Steel, both by Mr. Wm. B. Phillips, give full statistics of production and consumption, as well as interesting historical data, and reports of the condition of various markets. Many of the other articles in this volume deserve mention, but lack of space forbids further detail. It may be said, however, that everything necessary is presented, and nothing unnecessary or unreliable is given; in other words, the volume contains no trash.

One of the most noticeable features of the volume is the uniform and systematic manner in which the results are presented. The uniform arrangement of statistics is a matter requiring the greatest labor and statistical ability. Compiling a single table of statistics is a simple matter, but arranging a vast mass of statistics, relating to many diverse subjects, on a uniform and intelligible basis, is entirely another matter, and requires the highest skill of the statistician. In the Mineral Industry this has been accomplished in a most successful manner; everything is clear and intelligible at the first glance, and everything is in its proper place. A great detriment to the systematic presentation of statistics has been, as pointed out by the editor, the necessity of using our present system of weights and measures, with “our long and short tons, our barrels of 200, 280, 300 or 400 lbs, our pounds avoirdupois and our pounds Troy, our bushels of a dozen different weights, and our gallons of several incomprehensible kinds”; but the disadvantages of this system have been partly avoided in many cases by giving the statistics in metric measures as well as in our own.

The question of the cost of production has been given especial prominence in this volume, with a view to showing the reduction in the cost of the crude products. To use the words of the editor: “The itemization of cost is the first essential step in securing economy in producing any article, and the history of every country and of every industry has shown that prosperity, whether national, industrial, or individual, is, in a general way, inversely proportional to the cost of supplying the rest of the world with what one produces.” These reductions are in no way dependent on the reduction of wages. On the contrary, many of the mining industries where the greatest reduction in cost of production has been accomplished, are carried on with high priced labor; and in many other cases, where the wages are not high, the condition of the wage-earners has been greatly improved. The reduction in cost of production has been entirely brought about by improvements in mining machinery, by a more thorough understanding of the nature of the deposits to be worked, and by more intelligent management and labor. The reduction in cost of production is nowhere better seen than in the materials most necessary to our welfare. For instance, coal can in some cases be carried by rail for 400 miles and delivered on board vessels for from $2 to $2.25 per ton, and yet the mine owners and railroads make dividends; some of the manufacturing establishments in Western Pennsylvania obtain coal at from 60 to 75 cents per ton at their works; hard gold-bearing quartz can be crushed, washed and 95 per cent. of the gold saved on the plates for $1.25 per ton; high grade Bessemer iron ore can be mined, handled, shipped and delivered a thousand miles from the point of production for less than $4.00 per ton. All these figures seem almost incredible until one investigates the various devices which the ingenuity and better education of those engaged in the industry have invented for reducing the expenses of production.

The former annual statistical numbers of the Engineering and Mining Journal were excellent in all they undertook, but the present volume, the Mineral Industry, makes a great advance in giving the statistics for foreign countries in addition to those of the United States. By so doing it gives the American producers an opportunity to know the present, past and probable future conditions of competition in foreign countries.

The two most important features in any statistical work are accuracy and promptness. The necessity of accuracy is self-evident, and without promptness the statistics lose much of their serviceability to those most interested in them, for the statistics of an industry published a year or two years late are rarely of much value to those engaged in that industry. The business man wants his statistics immediately after the expiration of the time to which they relate, so that he may know the existing condition of the industry in which he is engaged; but if he does not get these statistics until many months or even several years afterwards, the condition of the industry may have changed entirely since the time to which the statistics refer. It is the promptness with which this volume is issued, combined with a high degree of accuracy, far greater than would be expected in statistics so hastily compiled, that gives it its especial value.

In conclusion, it may be said, that as a piece of statistical work, relating to an industry that is world-wide in its scope, combining accuracy with full detail and systematic arrangement, and issued so soon after the close of the time to which it relates, the Mineral Industry has never been equaled in this country or abroad. The former statistical numbers of the Engineering and Mining Journal, which referred mostly only to American mining, were considered remarkable pieces of statistical work, on account of the promptness of their publication; but in the Mineral Industry we have an epitome of the mining operations of every quarter of the globe, published almost immediately after the close of the time to which they refer, a feat which heretofore would have been declared impossible. This accomplishment is most creditable to the editor, Mr. Rothwell, to the systematic organization of the Scientific Publishing Co., and to the business manager, Mrs. Braeunlich, by whose business ability such an expensive undertaking is made commercially practicable. The volume will be found of the greatest value to the economic geologist, the miner, the engineer and the business man.

R. A. F. PENROSE, JR.

FOOTNOTES

[54] Geological Observations in South America, 1846.

[55] Beiträge zur Geologie und Paleontologie der argentinischen
Republik; I. Geologischer Theil, 1885.

[56] Studien über Cordillerengesteine. Apolda, 1875.

[57] Reisen in den Cordilleren der argentinischen Republik, Verh.
der Gesellsch. für Erdkunde. Berlin, 1891.

[58] Untersuchungen an altkrystallinen Schiefergestenien aus dem
Gebiete der argentinischen Republik, von B. Kühn. Neues
Jahrbuch für Min., etc., Beit. Bd. VII., 1891, p. 295.

[59] Untersuchung argentinischer Pegmatite, etc., von P. Sabersky,
_ib._, p. 359.

[60] Untersuchungen an argentinischen Graniten, etc., von J.
Romberg, _ib._, VIII., pp.

_ANALYTICAL ABSTRACTS OF CURRENT LITERATURE._[61]

_A New Tæniopteroid Fern and its Allies._ By DAVID WHITE. (Bulletin
Geological Society of America, 4 pp., 119–122, pl. I.).

Mr. White has described, under the name of _Tæniopteris missouriensis_, a new and well characterized fern from the Lower Coal-measures in the vicinity of Clinton, Henry County, Missouri. Botanically, it is of particular interest in that it combines the so-called tæniopteroid and alethopteroid types of structure, while geologically it is of much value in supplying a readily identified stratigraphic mark in a part of the Carboniferous not especially rich in fossil plants. After thoroughly describing it and considering its specific and generic resemblances, the author discusses at length its suggested genetic relations and represents in a graphic manner a scheme of its probable ancestors and line of descent.

F. H. K.

* * * * *

_Rainfall Types of the United States._ Annual Report by
Vice-President GENERAL A. W. GREELY. (The National Geographic
Magazine. Vol. V., April 29, 1893, pp. 45–58 pl. 20).

The paper confines itself to the characteristic distribution of precipitation throughout the year and gives the rainfall types of the country.

(a) The best defined type of rainfall within the United States is that which dominates the Pacific coast region as far east as western Utah. The characteristic features are a very heavy precipitation during midwinter, and an almost total absence of rain during the late summer. (b) The characteristics of the Mexican type, dominating Mexico, New Mexico and western Texas, are a very heavy precipitation after the summer solstice and a very dry period after the vernal equinox. August is the month of greatest rainfall, while February, March and April are almost free from precipitation. (c) The Missouri type covers the greatest area, dominating the watersheds of the Arkansas, Missouri and upper Mississippi rivers, and of lakes Ontario and Michigan. It is marked by a very light winter precipitation, followed in late spring and early summer by the major portion of the yearly rain, the period when it is most beneficial to the growing grain. (d) The Tennessee type, prevailing in Kentucky, Tennessee, Arkansas, Mississippi and Alabama, has the highest rainfall the last of winter, while the minimum is in mid-autumn. (e) The Atlantic type, covering all the coast save New England, is one where the distribution throughout the year is nearly uniform, with a maximum precipitation after the summer solstice, and a minimum during mid-autumn. (f) The St. Lawrence type is characterized by scarcity during the spring months, heavy rainfall during the late summer and late autumn months, with a maximum during November.

The regions lying between these several type-regions have composite rainfall types, resulting from the influence of two or more simple types.

H. B. K.

* * * * *

_The Geographic Development of the Eastern Part of the Mississippi
Drainage System._ By LEWIS G. WESTGATE, Middletown, Conn.
(American Geologist, Vol. XI, April, 1893, 15 pp.)

The drainage of the Eastern Mississippi basin in post-carboniferous was in all probability consequent upon the tilting which accompanied the stronger folds of the Appalachian revolution in the east. The present drainage is found to accord in the main with this hypothetical post-carboniferous drainage, but several streams depart quite widely from it.

(a) The great drainage lines of the St. Lawrence basin are structural valleys developed along the strike of the softer Paleozoic strata, and at right angles to the original surface. The streams seem, therefore, to have adjusted themselves to the differences in hardness and structure of the beds discovered. (b) The Ohio and Cumberland rivers cut directly across the Tennessee and Cincinnati anticlines. The most probable explanation is that the rivers were superimposed upon the arched and eroded Silurian rocks from a thin cover of carboniferous beds--now entirely removed. (c) The Upper Mississippi does not follow the dip of the rocks to the southwest, but follows the strike to the southeast. This part of the river probably dates from the elevation of the plains on the west and the Appalachians on the east, which marked the close of the Cretaceous and which left a broad north and south valley. (d) The author finds good reason to believe that the Lower Mississippi, in post-carboniferous times, flowed west through Missouri and Arkansas. The present course was probably taken at the close of the Cretaceous in consequence of elevations on the west and east, and possible depression in the south.

The Cretaceous base-level recognized by Davis on the Atlantic slope can be traced more or less discontinuously, and remnants of it are believed to exist in Kentucky, Tennessee, Wisconsin, Minnesota and Arkansas. But in general the work of the Tertiary cycle has obliterated almost all evidence of it on all but the hard sandstones and conglomerates of the Paleozoic series.

Good examples of the lowlands excavated from the Cretaceous base-level during the Tertiary cycle, are the Valley of the East Tennessee and the central lowland of Kentucky and Tennessee. During the post-Tertiary sub-cycle the larger streams trenched to greater or less extent these lowlands. No attempt is made to carry the history of the development of the Mississippi, drainage into the complicated chapter of the ice-invasion.

H. B. K.

* * * * *

_On a New Order of Gigantic Fossils._ By ERWIN H. BARBOUR. (University
Studies. Published by the University of Nebraska. Vol. I, No. 4,
July, 1892, pp. 23, pl. 5).

A part of Sioux County, Nebraska, lying north of the Niobrara River, has yielded a new order of gigantic Miocene fossils unlike anything heretofore known. They are best described as fossil corkscrews, of great size, coiling in right-handed or left-handed curves about an actual axis or around an imaginary axis. The screws are often attached at the bottom to an immense transverse piece, rhizome, underground stem, or whatever it may be, which is sometimes three feet in diameter. In other cases the corkscrew ends abruptly downward, as it always does upwards. In still other cases the transverse piece is variously modified, and sometimes blends into the sandstone matrix, as if the underground stem, while growing at one end, was decaying at the other. The fossil corkscrew is invariably vertical, and the so-called rhizome invariably curves rapidly upwards, and extends outwards an indefinite distance.

That they could ever have been formed by burrowing animals, by geysers or springs, or by any mechanical means whatever, is entirely untenable. Their organic origin is unquestionable. Microscopic sections show smooth spindle-shaped rods, which are suggestive of sponge spicules. From the numbers seen in place it is evident that they flourished in thickly crowded forests of vast extent.

A finely preserved rodent’s skeleton was found in one great stem. The probable explanation is not that the rodent burrowed there, but that its submerged skeleton became an anchorage for a living, growing Daimonelix, which eventually enveloped it.

The author proposes this provisional classification:

Order. Family. Genus. Species.
{ Daimonelicidæ. { Daimonelix. { circumaxilis
{ { { bispiralis
------ { -------------- { ----------- { anaxilis
{ { { robusta
{ { { carinata.
{ ----------- { ------
{ ----------- { ------

The different species are described in full.

H. B. K.

* * * * *

_The Vertical Relief of the Globe._ By HUGH ROBERT MILL, D.Sc.,
F.R.S.E. Scottish Geographical Magazine, April, 1890.

The purpose of Dr. Mill’s paper is to show a simple yet adequate basis on which to build the superstructure of physical geography. It does not attempt a discussion of the distribution and varieties of vertical relief. The structure of the earth is stated most simply by describing it as an irregular stony ball, covered with an ocean and an envelope of air. If the lithosphere were perfectly smooth and at rest, with the hydrosphere uniformly spread over its surface, the former would have the form of the terrestrial spheroid, and the latter would surround it to a depth of 1.7 miles. The surface of this hypothetical spheroid Dr. Mill calls _mean sphere level_. Of course, in reality the surface of the lithosphere is not perfectly smooth. Parts of it are greatly depressed and parts much elevated, the latter forming the land of the earth. The writer proceeds to calculate the position of mean sphere level, and in the absence of accurate data he uses the careful estimates of Dr. John Murray, which are as follows: Average depths of oceans = 2.36 miles; average height of land = .426 miles; average thickness of hydrosphere surrounding smoothed lithosphere = 1.7 mile; area of land = 55,000,000 square miles; area of oceans = 141,700,000 square miles. Suppose a block of 55,000,000 of square miles area and 1.7 miles deep to be cut out of the smoothed lithosphere and set down on the surface alongside the depression. No change will take place in the surface of the hydrosphere. If the surface of the 141,700,000 square miles of lithosphere were reduced to uniformity, the whole depressed area would lie .66 mile beneath mean sphere level, and the depth of the ocean becomes 2.36 miles. To raise the land to its actual mean level above the hydrosphere surface, a sufficient quantity of matter must be removed from the depressed area and placed on the elevated block. Let _x_ = the thickness of the belt removed and _y_ equal the thickness of the belt when placed on the elevated block. Then _x_ + _y_ is the height of the land above the actual hydrosphere level. From the data given the following equations are easily obtained:

_x_ + _y_ - .426 = 0
141.7 _x_ - 55 _y_ = 0
_x_ = .12 and _y_ = .306 in miles.

The average height of the land above mean sphere level is thus 1.7 + .306 = 2.006 miles, and the average depth of the depressed portion beneath mean sphere level is .66 + .12 = .78 mile.

Dr. Mill divides the earth into the three following divisions: (1) _Abysmal area_, occupying all the depressions beneath the mean surface of the lithosphere, occupying 50 per cent. of the earth’s surface; (2) _Transitional area_, comprising all the regions above mean sphere level covered by the hydrosphere, occupying 22 per cent. of the surface; (3) _Continental area_, all the lithosphere that projects above the hydrosphere, or 28 per cent. of the earth’s surface.

J. A. B.

FOOTNOTE

[61] Abstracts in this number are prepared by F. H. Knowlton, Henry B.
Kummel, J. A. Bownocker.

_ACKNOWLEDGMENTS._

The following papers have been donated to the library of the Geological Department of the University of Chicago:

ABBOTT, CHARLES C., M.D.

--Recent Archæological Explorations in the Valley of the Delaware.
30 pp., 1 pl.--Publications of the University of Pennsylvania.
Series in Philology, Literature and Archæology, Vol. II, No. 1.

ADAMS, FRANK D.

--On Some Granites from British Columbia and the Adjacent Parts of
Alaska and the Yukon District. 14 pp., Ill.--Canadian Record of
Science, Sept. 1891.

--Notes to Accompany a Tabulation of the Igneous Rocks based on the
System of Professor H. Rosenbusch. 6 pp., 1 pl.--Canadian Record of
Science, Dec. 1891.

--On the Geology of the St. Clair Tunnel. 8 pp., 1 pl.--Trans. Roy.
Soc. Canada, Section IV, 1891.

--On the Presence of Chlorine in Scapolites. 5 pp.--Am. Jour.
Science, Apr. 1879.

--Notes on the Lithological Character of some of the Rocks
Collected in the Yukon District and Adjacent Northern Portion of
British Columbia. 6 pp.--Annual Report, Geol. Sur. of Canada, 1887.

--On Some Canadian Rocks Containing Scapolite, with a Few Notes on
Some Rocks Associated with the Apatite Deposits. 16 pp.--Canadian
Record of Science, Oct. 1888.

--On the Microscopical Character of the Ore of the Treadwell Mines,
Alaska. 5 pp., Ill.--Read before the Royal Soc. Canada, May, 1889.

--On a Melilite-Bearing Rock (Alnoite) from Ste. Anne de Bellevue,
near Montreal, Canada. 10 pp., Ill.--Am. Jour. Sci., Vol. XLIII,
Apr. 1892.

AMI, HENRY M., M.A., F.G.S.

--The Utica Terrane in Canada. 32 pp.--Canadian Record of Science,
Oct. 1892.

--Additional Notes on the Geology and Palæontology of Ottawa and
its Environs. 11 pp.--Ottawa Naturalist, Sept. 1892.

--Catalogue of Silurian Fossils from Arisaig, Nova Scotia. 7
pp.--From the Nova Scotian Inst. of Sci., Ser. 2, Vol. I, 1892.

ANDREAE, A.

--Ueber die Nachahmung verschiedener Geysirtypen und über
Gasgeysire. 6 pp.--Gesammt-Sitzung vom 13 Jan. 1893.

BAYLEY, W. S.

--A Summary of Progress in Mineralogy and Petrography in
1892.--American Naturalist.

BECKER, GEORGE F.

--Finite Homogeneous Strain, Flow and Rupture of Rocks. 77
pp.--Bull. Geol. Soc. Am., Jan. 1893.

BEECHER, C. E.

--Notice of a New Lower Oriskany Fauna in Columbia Co., N. Y. 4
pp.--Am. Jour. Sci., Vol. XLIV, Nov. 1892.

BRANNER, J. C.

--Annual Reports of the Arkansas Geological Survey, 1888, Vols. 1,
2, 3, 4; 1889, Vol. 2; 1890, Vols. 2 and 3.

BRYCE, GEORGE, LL.D.

--Older Geology of the Red River and Assiniboine Valleys with an
Appendix. 7 pp., Ill. Read before the Historical and Scientific
Society of Manitoba, Nov. 1891.

BROADHEAD, G. C.

--A Bibliography of the Geology of Missouri, by F. A. Samson. 178
pp.

--Report of the Geological Survey of the State of Missouri,
including Field Work of 1873–4, with 91 illustrations and an atlas.
788 pp.

--Preliminary Report on the Coal Deposits of Missouri from Field
Work prosecuted during the years 1890–91, by Arthur Winslow, State
Geologist. 220 pp. 1 pl., 131 Illustrations.

CARTER, OSCAR, C. S.

--Artesian Wells as a Water Supply for Philadelphia. 4 pp.--Proc.
of the Chem. Section of the Franklin Inst., Jan. 1893.

CHAMBERLIN, T. C.

--The Requisite and Qualifying Conditions of Artesian Wells. 42 pp.
1 pl. Extract, Fifth Annual Report of the Director U. S. G. S.

--Boulder Belts Distinguished from Boulder Trains--Their Origin and
Significance. 4 pp.--Bull. Geol. Soc. Am. Vol. I., 1879.

--Some Additional Evidence Bearing on the Interval between the
Glacial Epochs. 11 pp.--Bull. Geol. Soc. Am., Vol. I., 1890.

--The Attitude of the Eastern and Central Portions of the United
States during the Glacial Period. 8 pp.--Am. Geol., Nov. 1891.

--A Proposed System of Chronologic Cartography on a Physiographic
Basis. 3 pp.--Bull. Geol. Soc. Am., Vol. II., 1891.

--(and R. D. SALISBURY.)

--On the Relationship of the Pleistocene to the Pre-Pleistocene
Formation of the Mississippi Basin, South of the Limit of
Glaciation. 17 pp.--Am. Jour. Sci., Vol. XLI., May 1891.

CHANEY, L. W. JR.

--Cryptozoön Minnesotense in the Shakopee Limestone at Northfield,
Minn. 3 pp.--Bull. Minn. Acad. Sci., Vol. III., No. 2.

CLARKE, PROFESSOR F. W.

--A Number of Pamphlets by Different Authors; 5 Volumes of the
Hayden Survey of the Territories.

COOKE, J. H.

--Geological Notes on Gozo. 6 pp.--Geol. Mag., Aug. 1891.

--Notes on Stereodon Melitensis, Owen. 2 pp.--Geol. Mag., Dec. 1891.

--On the Occurrence of a Black Limestone in the Strata of the
Maltese Islands. 3 pp.--Geol. Mag., Aug. 1892.

--The Mediterranean Naturalist. From Aug. 1, 1891, to Sept. 1,
1892, inclusive.

CROSBY, W. O.

--Notes on the Physical Geography and Geology of Trinidad. 11
pp.--Proc. Boston Soc. Nat. Hist., Oct. 1888.

--On the Joint Structure of Rocks. 5 pp.

--On a Possible Origin of Petrosilicious Rocks. 9 pp.--Proc. Boston
Soc. Nat. Hist., March 1879.

--On the Classification of the Textures and Structures of Rocks. 9
pp.--Proc. Boston Soc. Nat. Hist., Nov. 1881.

--On the Elevated Reefs of Cuba. 6 pp.--Proc. Boston Soc. Nat.
Hist., June 1883.

--On the Chasm called “Purgatory,” in Sutton, Mass. 2 pp.--Proc.
Boston Soc. Nat. Hist., Oct. 1883.

--Origin of Continents. 11 pp.--Geol. Mag., June 1883.

--On the Relationship of the Conglomerate and Slate in the Boston
Basin. 20 pp.--Proc. Boston Soc. Nat. Hist., Jan. 1884.

--Quartzites and Siliceous Concretions. 10 pp.--Technology
Quarterly, May, 1888.

--Relations of the Pimite of the Boston Basin to the Felsite and
Conglomerate. 14 pp.--Technology Quarterly, Feb. 1889.

--The Madison Bowlder. 9 pp., 1 pl.--Appalachia, Vol. VI, No. 1.

--On the Contrast in Color of the Soils of High and Low Latitudes.
10 pp.

--Geology of the Outer Islands of Boston Harbor. 8 pp.--Proc.
Boston Soc. Nat. Hist., 1888.

--Physical History of the Boston Basin. 22 pp.--Lectures to
Teachers’ School of Science, 1889–90.

--The Kaolin in Blandford, Mass. 9 pp.--Technology Quarterly, Aug.
1890.

--Composition of the Till or Boulder-Clay. 25 pp.--Proc. Boston
Soc. Nat. Hist., Vol. XXV, 1890.

--Geology of Hingham, Mass. 12 pp., 3 maps.--Proc. Boston Soc. Nat.
Hist., Vol. XXV, May, 1892.

--Geology of the Black Hills of Dakota. 29 pp.--Proc. Boston Soc.
Nat. Hist., Vol. XXIII.

CULVER, G. E.

--On a Little Known Region of Northwestern Montana. 18 pp., 1
pl.--Wis. Acad. Sci., Arts and Letters, Dec. 1891.

DARTON, N. H.

--The Relations of the Traps of the Newark System in the New Jersey
Region. 82 pp., 1 map, 4 pl.--Bull. U. S. G. S.

--On Fossils in the Lafayette Formation in Virginia. 3 pp.--Am.
Geol., March, 1892.

DERBY, O. A.

--On Nepheline Rocks in Brazil. 15 pp., Ill.--Quart. Jour. Geol.
Soc., 1891.

DOUGLAS, JAMES.

--Biographical Sketch of Thomas Sterry Hunt. 11 pp.--Trans. Am.
Inst. Min. Engin.

EYERMAN, JOHN.

--Notes on Geology and Mineralogy. 4 pp.--Proc. Acad. Nat. Sci.,
Phila., 1889.

--The Mineralogy of Pennsylvania, Part I. 54 pp.

--Bibliography of North American Vertebrate Paleontology for the
year 1889. 4 pp.--Am. Geol., 1890.

--Bibliography of North American Vertebrate Paleontology for the
year 1890. 8 pp.--Am. Geol., 1891.

--On the Mineralogy of the French Creek Mines in Pennsylvania. 4
pp.--N. Y. Acad. Sci., 1889.

--A Catalogue of the Paleontological Publications of Joseph Leidy,
M.D., LL.D. 10 pp.--Am. Geol., Nov. 1891.

--Bibliography of North American Vertebrate Paleontology for the
year 1891. 8 pp.--Am. Geol., April, 1892.

FELIX, JOHANNES.

--Untersuchungen ueber fossile Hölzer. 12 pp., 1 pl.--Abdruck a. d.
Zeitschr. Deutschen geolog. Gesell., 1887.

--Beiträge zur Kenntniss der Gattung Protosphyraena Leidy. 24 pp.,
3 pl.--Aus der Zeitschr. Deutschen geolog. Gesell., 1890.

--Ueber die tektonischen Verhältnisseder Republik Mexiko. 20 pp., 2
pl.--Aus der Zeitschr. Deutschen geolog. Gesell., 1892.

FERRIER, W. F.

--Rapport Géologique. Rapport des Opérations de 1866 à 1869. 530
pp., with maps.

--Descriptive Sketch of the Physical Geography and Geology of the
Dominion of Canada, by Alfred R. C. Selwyn and G. M. Dawson. 55 pp.
1884.

--List of Publications of the Geological and Natural History Survey
of Canada. 36 pp.

--Geological and Natural History Survey and Museum of
Canada.--Report of Progress, 1882–83–84. Annual Report for 1888–89.

FISHER, REV. O.

--The Hypothesis of a Liquid Condition of the Earth’s Interior
considered in Connection with Professor Darwin’s Theory of the
Genesis of the Moon. 14 pp.--Proc. Cambridge Phil. Soc., 1892.

GILBERT, G. K.

--Continental Problems. Annual Address by the President of the
Geological Society of America. 12 pp., Ill.--Bull. Geol. Soc. Am.,
1893.

--The Moon’s Face. A Study of the Origin of its Features. 52 pp., 1
pl.--Phil. Soc. Washington, 1893.

DEGEER, BARON GERARD.

(The following pamphlets are in the Swedish language, the titles
being translated):

--On the Occurrence of Hydrous Manganese Oxide between the Pebbles
of the Osar at Upsala. 4 pp.--Aftryck ur Geol. Föreningens i
Stockholm Förhandl., 1882.

--On Actinocamax Quadratus. 3 pp.--Ibid. Bd. VII.

--On Kaolin and other Minerals, derived from decayed Archaean rocks
in the Cretaceous near Kristianstad. 8 pp.--Ibid. Bd. VII.

--Discussion of the Conglomerate at Vestani in Scania. 5 pp.--Ibid.
1886.

--On Folded Veins in Archaean Rocks. 5 pp.--Ibid. 1887.

--On Windworn Stones. 20 pp.--Ibid. 1887.