γ on 19 new spectroscopic L Cassiopeiae, r Ophiuchi and a Pegasi to the list. Roberts inquires into the variation of the spectroscopic binary κ Pavonis, and Russell has calculated the mass ratios of Krueger 60 and Castor. Orbits of several spectroscopic binaries were investigated by Cannon and Plaskett, the latter of whom has discussed the errors of radial velocity work and their causes, concluding that the better determinations are accurate within one km. per sec. Campbell's second catalogue of spectroscopic binaries includes over 300 of these objects, which, with radial velocities, or motion in the line of sight, are now absorbing extensively the energies of the great observatories. Stebbins, from his discovery of eclipsing variables, directs attention to a new departure in accurate photometric observation furnished by the spectroscopic binaries. He finds 8 Aurigae an eclipsing variable, whose epochs of light minimum accord exactly with the times predicted from the spectroscopic elements derived by Baker. There is evidence, too, that the surface intensity of both components far exceeds that of the sun itself. Utrecht fix the last maximum at measures Spectroscopic Binaries.-Lee gives Radial Velocities.-Radial velocities are continued at Allegheny by Jordan and Daniels. Münch has given an exhaustive discussion of the radial velocities of Sirius, and Bélopolsky has extended his measurements to many of the standard stars, among them Arcturus and 8 Geminorum. Campbell reports very satisfactory progress of the radial-velocity work of the D. O. Mills expedition to the Southern Hemisphere. More than 3,000 spectrograms have been secured and measured, and two additional years of work have been provided for by Ogden Mills, son of the original donor. The Lick Observatory has published the detailed results of the expedition in a volume containing a catalogue of 150 stars whose radial velocities have been determined, and the velocities of about one-fourth of them are found to be variable. Campbell gives the results of a thorough discussion of the brighter helium or Class B stars, in or near the Milky Way, and whos radial velocity with reference to the solar system is about 20 km. per sec. Also he directs attention to some peculiarities in stellar motions, finding that the velocities of stars are functions of their spectral types; and that planetary nebulae have perhaps been formed from stars through collisions with, or close approaches to, other massive bodies. Frost is investigating the sun's velocity with respect to stars of spectral type A, Adams reports a half-dozen stars with great radial velocities (96 to 170 km. per sec.), and ripe fruit of the spectroscopic method inaugurated by Sir William Huggins nearly a half century ago is now being gathered on every hand. Nebulae.-Porter's work and that of Bauschinger have led to new catalogues of nebulae. R. Wilson observes the relation of the Orion nebula to the stars therein. Wolf discusses spectrograms of the "America" nebula, and Fath investigates the spectra of spiral nebulae and globular star clusters from the Lick and Mt. Wilson photographs. Fabry shows the advantages of applying the interference method to the study of nebulae. Pahlen connects the photographic forms of spiral nebulae with a type of logarithmic spiral, and Belot in his Cosmogonie Tourbillonnaire sets forth a novel and ingenious application of a swiftly moving vortex to account for the successive formation of the planets of the solar system. Wilde, first Halley lecturer at Oxford, develops the theory of celestial ejectamenta, Sutherland theorizes on spiral structure in nebulae, and Very makes the white nebulae galaxies. Bibliography.-Puiseux, in the Revue Général des Sciences, and Stroobaut, in the compact little Belgian Annuaire Astronomique for 1912, give excellent resumés of recent astronomical progress, the latter fully summarizing the observations of Halley's comet at its recent appearance. Römer's Adversaria has been published by the Royal Danish Academy of Sciences. The scientific papers of the elder Herschel are at last, after nearly a century, in process of collection and publication, under Dreyer's capable editorship and the auspices of both the Royal and the Royal Astronomical Societies. Warren's The Earliest Cosmologies treats of the world concepts of the ancients. Markwick reviews in The Observatory the astronomical allusions in Milton. The Royal Astronomical Society of Canada issues an observer's Handbook, and the "Companion" to The Observatory is particularly useful to observers of meteors, doubles, variables and satellites. Cowell succeeds Downing as superintendent of the British Nautical Almanac, and the issue of 1913 is the first under his direction. The advanced calculations of theoretic astronomy have been greatly facilitated by the new logarithmic-trigonometric tables with 8-decimal places by Bauschinger and Peters. Whittaker has published a History of the Theories of Aether and Electricity. The Madrid Observatory has published its Anuario, and the 4th edition of Newcomb-Engelmann's Populäre Astronomie, fully revised by the Potsdam staff, has appeared; also a new star atlas and telescopic handbook by Norton, and Barritt's Monthly Star Map is of wide interest to amateurs. The 11th edition of the Encyclopedia Britannica contains many excellent articles on astronomy. Round the Year with the Stars by Serviss will enthuse many a student, whether young or old; and The Spectroscope and its Work, by Newall, deals acceptably, though in elementary fashion, with every phase of astronomical application of this instrument. cott's Star Lore of All Ages treats of myths and legends of the northern constellations. Vol. iii of Transactions of the International Union for Co-operation in Solar Research reports in extenso the Mount Wilson conference. Hinks has published a brief general treatise, and Pomona College has begun a popular serial. Other recent works are Trabert's Lehrbuch der Kosmischen Physik and Abbot's The Sun. XXVII. GEOLOGY, METEOROLOGY, TERRESTRIAL MAGNETISM, AND GEOGRAPHY GEOLOGY DYNAMIC AND STRUCTURAL GEOLOGY J. B. WOODWORTH Isostacy. The question whether the transfer of load on the earth's surface in the form of sediments from an area of erosion to one of deposition is competent to cause a rise of the denuded tract and a depression of an adjacent loaded zone has been a matter of much debate among geologists ever since the statement of the doctrine under the name of "isostacy" was put forth by Dutton. Just as Edouard Suess early in the year (Amer. Jour. Sci., xxxi, Feb. 12, 1911, pp. 101-108) cried out "I must confess myself a heretic in all regarding isostacy," Dr. John F. Hayward of the U. S. Coast and Geodetic Survey stated (Science, Feb. 10, 1911) that geodetic observations have furnished proof that a close approximation to the conditions called isostacy exists in the earth and comparatively near the surface. According to these observations the isostatic compensation under the United States is nearly complete. The average both of excess and deficiency of mass in areas lacking compensation or balance is represented by a sheet of rock only 250 ft. thick having the average density (2.67) of the surface portion of the earth. This is the most cogent statement on the affirmative side of the controversy which has yet been made. Dynamic Geology.-Aside from the problems of vulcanism and earthquakes stated elsewhere, but small advances have been made in dynamic geology during the year. John Mil lis (Science, xxxiv, 1911, p. 61) suggests as the initial step in the production of the oval hills of till called drumlins in the glaciated area the filling of hollows on the surface of a melting ice sheet. The ripple mark of certain layers of the Carboniferous Waverly series in Ohio maintain directions nearly northwest and southeast over SO large an area that Jesse Hyde (Journ. Geol., xix, 1911, pp. 257269) believes the phenomenon to be due to wind-made waves swinging into parallelism with a shoal or shore on the south-southwest rather than to the undeflected direction of the prevalent winds of the time. The same writer calls attention (Amer. Jour. Sci., xxxi, 1911) to the existence of an ancient land surface at the base of the Carboniferous coal measures in southern Ohio without trace of a soil bed. Inexpert or casual observers in all countries are inclined to attribute picturesque and wild, steep-walled depressions in the earth surface to the more violent causes active in nature, such as volcanic explosions and the sudden fractures which give rise to earthquakes. Cliff Lake Gorge in the Madison valley in Montana is an example locally regarded as a volcanic crater long extinct. Dr. G. R. Mansfield (Bull. Geog. Soc. Phila., ix, 1911) shows that the lake has been formed by landslides blocking a valley cut by running water in an ancient lava flow. Coal Formation.-W. H. Twenhofel from a study of peat beds on Anticosti Island (Amer. Jour. Sci., 1910) draws the conclusion that many of the evidences which have been adduced for the development of coal beds from transported vegetable matter may be permissive of an origin through growth in situ. It is pertinent to note that in Englishspeaking countries the formation of coal through the growth of plants upon the spot where the coal is found prevails, while the French geologists hold to the hypothesis of transportation and deposition at a distance. the real nature of the banded gneisses and schists regarded in Sir Charles Lyell's time as metamorphosed sediments in all instances. Chas. H. Clapp reports on certain examples on Vancouver which prove to be altered plutonic rocks. 1910) he describes the geological structure of the Mt. McKinley region. Dr. Phillip Smith and й. M. Eakin, in A Geologic Reconnaissance in South-Eastern Seward Peninsula and the Norton Bay-Nulato Region, Alaska (Bull. U. S. Geol. Survey, 449, 1911), describe the geology of that heretofore little known district. Other reports are newly out on the geology and mineral resources of the Nizina district, by Moffit and Capps, and on the Prince William Sound region by Prof. U. S. Grant and D. F. Higgins (Bulls. 443 and 448). Alaska.-No surveys of recent years have so much extended our knowledge of the geological structure of the continent as those carStructural Geology. The vast ried on in Alaska, under conditions area of undescribed rocks of the of travel the accounts of which, if western mountain region yield each written, would constitute the story of year important results in the light the overland search for the Norththey throw upon the structure of west Passage. Alfred H. Brooks, of the continent and its past life. W. the Geological Survey, and a corps J. Sinclair and Walter Granger in a of fellow geologists have in numerous recent paper (Bull. Am. Mus. Nat. reports shown piece by piece that Hist., xxx, 1911, pp. 85-177) describe this vast region is a continuation of the older Tertiary beds of the Wind the general geological structure of River and Big Horn basins. The the western Cordilleras. In a rewriters believe that the alternating cent article (Professional Paper 70, red and blue clays of the region represent arid and moist climatic cycles respectively. Prof. J. C. Merriam in another article (Bull. Dept. Geol., Univ. of Calif., Nov., 1910) gives an account of the strata containing the remains of Tertiary mammals in Virgin Valley and Thousand Creek in northwestern Nevada. F. H. Knowlton brings to notice (Science, Sept. 8, 1911, pp. 319322) the curious absence of dinosaurs in the Laramie and their presence in the overlying beds of the Fort Union series. The geological structure of the region between Albuquerque, N. M., and Kingman, Ariz., including the essential features of the Grand Cañon of the Colorado, is described by N. H. Darton (Bull. 435, U. S. Geol. Survey, 1910). This bulletin forms a handy vade mecum of geology for the visitor to the Grand Cañon. L. F. Noble (Amer. Jour. Sci., xxix, 1910) contributes a detailed account of the strata in the Shinumo district of the Grand Cañon. The Summary Report of the Geological Survey Branch of the Department of Mines of Canada for 1910 (Ottawa, 1911) contains the results of much new work in the geological structure of the mountainous region of British Columbia. Mention may be made of the advances in the understanding of Eastern United States.-The progress of structural geology in the longer studied rocks of the eastern United States is shown by closer distinctions in matching the records of adjacent ancient sea-bottoms and land-surfaces, and in the details of structure originating in the fracture and displacement of rocks. Prof. Cushing (Amer. Jour. Sci., Feb. 1911) represents the geographical conditions of the Adirondack region during the Palæozoic era as involving alternating subsidence and elevation on the eastern and western borders of the tract. It seems to him unlikely that the Adirondack area has been entirely submerged since the earliest geological records. The geology of the popular Thousand Island region of northern New York is described by Messrs. Cushing, Fairchild, Reudemann, and Smyth in a recent bulletin (No. 145, 1910) of the State Museum. Dr. John M. Clarke, in the 30th Report of the N. Y. State Geologist (Museum Bulletin 149, 1911), writes most lucidly on the geology of the Gulf of St. Lawrence, including the Magdalen Islands. In A Contribution to the Geologic History of the Florida Plateau (Publication 13, Carnegie Institution, Washington, 1910), Dr. T. W. Vaughan gives an account of the known geological structure and changes of level of Florida. Contrary perhaps to the general opinion, coral reefs are stated to have played an important part in building up the peninsula only in Pleistocene time or during what is commonly known as the glacial period. The extensive tunnels excavated beneath New York City and its vicinity in the construction of subways and the new aqueduct have exposed endless details of the local rock structure, which Dr. Berkey has laboriously recorded, together with their significance for further engineering work. ("Areal and Structural Geology of the Southern Manhattan Island," Annals N. Y. Acad. Sci., xix, pp. 247-282; also Geology of New York City Aqueduct, N. Y. State Museum Bull. 146, 1911.) Stratigraphy. The comprehensive attempt at a revision of the North American geological stratigraphic sequence mentioned last year is followed this year by a learned discussion of the same subject by E. O. Ulrich, with especial reference to the Paleozoic strata. ("Revision of the Palæozoic Systems," Bull. Geol. Soc. Amer., 1911.) The paper is noteworthy for its treatment of crustal displacements in relation to the shifting of areas of marine deposition. Like Prof. Scheuchert, the author, ascribes limited areas at any one epoch to the seas which covered portions of the North American continent in the early ages. The modifications proposed in the geological time scale are too extensive to be specifically mentioned in this note. It is clear that the old classification of geological formations does not adequately express geological history in the light of the most recent studies. No classification can be satisfactory which does not furnish suitable terms for the designation of successive epochs in the development of the sediments of the several continents. These contributions are notable advances towards the construction of a system which is to fulfil this requisite. Bibliography.-Want of space forbids more than mention of the various publications of the several state geological surveys. That of Tennessee under Ashley has adopted the innovation of issuing a monthly journal setting forth the results of the survey in popular form. The Lithology of Connecticut, by Prof. Joseph Barrell and G. F. Loughlin (Bull. 13, State Geological and Nat. Hist. Survey, 1910), contains a comprehensive description of the varieties of rocks of the state in terms adapted to the general reader. Circular No. 2 of the Oklahoma Geological Survey, Dr. C. N. Gould, Director, gives a brief account of the geological history of that state. The following state surveys have recently issued reports dealing with the geological structure controlling the underground distribution of natural resources: Washington, Prof. Henry Landes, Director; West Virginia, Dr. I. C. White, Director; Illinois, Dr. Frank W. De Wolff, Director. (See XXVII, State Geological Surveys.) Much geological structure is described in reports dealing primarily with the occurrence of ore deposits. A notable recent contribution of this nature is the report on the ore deposits of New Mexico (Professional Paper 68, U. S. Geol. Survey) by Messrs. Lindgren, Graton, and Gordon. (See Economic Geology, infra.) The U. S. Geological Survey has issued the following folios of the geologic atlas of the country_since the last volume of the YEAR BOOK: 170, Mercersburg-Chambersburg, Pa.; 171, Engineer Mountain, Col.; 172, Warren, Pa.-N. Y.; 173, LaramieSherman, Wyo.; 174, Johnstown, Pa.; 175, Birmingham, Ala.; 176, Sewickley, Pa.; 177, Burgettstown-Carnegie, Pa.; 178, Foxburg-Clarion, Pa.; 179, Pawpaw-Hancock, Md.-W. Va. |