UNE lO, 1922] 



NA rURE 



757 



jsometric readings for altitude were also taken. 

 The new work included the first complete traverse 

 of the Wadi er Rumma in its lower course, el Batin ; 

 the region southward to Zilfi and thence to Riyadh ; 

 much new detail between Riyadh and Buraida ; and 

 a completely new route from Buraida to Jauf and 

 between Jaiif and the Wadi Araba on the frontier 

 of southern Palestine. 



Death Valley. — An article is given in the U.S. 

 Monthly Weather Review of January last by Mr. 

 Andrew H. Palmer of the U.S. Weather Bureau on 

 the weather at the Bureau's substation at Greenland 

 Ranch in Death Valley, California. The valley 

 extends from north to south for a distance of about 

 100 miles, and lies between high mountain ranges. 

 The width varies from two to eight miles, and it is 

 the deepest depression in the United States. The 

 instrument shelter is 1 78 feet below sea level, and the 

 maximum and minimum thermometers with the 

 thermometer screen, as well as the 8-inch rain gauge, 

 are lent by the Weather Bureau. Unbroken weather 

 records are now available for more than ten years. 

 Nearly every summer the highest temperatures 

 observed in the United States occur in Death Valley. 

 The extreme maximum temperatures recorded during 

 the last eleven years, to 1921, range from 134'^ F. 

 in 1913 to 120° in 1912 ; the extreme of 134° F. 

 observed on July 10, 1913, is said to be the highest 

 natural air temperature ever recorded on the earth's 

 surface by means of a tested standard thermometer 

 exposed in a standard louvered screen. Tempera- 

 tures of 100° or higher occur almost daily during 

 June, July, and August; in July 1917 the mean 

 temperature was 107° -2. Not infrequently six con- 

 secutive months have passed without measurable 

 rain. In 191 7 the total rainfall was less than half 

 an inch, and the annual average precipitation is 

 less than two inches. There is said to be some 

 sunshine during practically every day in the year. 

 Four crops of alfalfa are gathered each year. 



Geological Research and Education in Con- 

 necticut. — The Connecticut State Geological and 

 Natural History Survey has collected its bulletins 

 issued between 1915 and 1920 as volume vi. of its 

 publications, which are distributed gratuitously " to 

 public libraries, colleges, and scientific institutions, 

 and to scientific men, teachers, and others who require 

 particular bulletins for their work, especially to those 

 who are citizens of Connecticut." The present thick 

 but easily opened volume contains over 11 00 pages, 

 with abundant plates, maps, and other illustrations. 

 Geologists will welcome Prof. R. S. Lull's treatise on 

 " Tria.ssic Life of the Connecticut Valley," as a record 

 of life and conditions on the land at the opening of 

 Mesozoic times. We are present, as it were, at the 

 rise of the dinosaurs, and the original restorations 

 serve admirably to impress the characters of these 

 dominant forms on the minds of every teacher in 

 the schools. Podokesaurus, recently discovered and 

 described by Miss M. Talbot, is fully discussed and 

 illustrated, for comparison with its Upper Jurassic 

 ally, Compsognathus. A complete review is given 

 of the footprints that abound in the shales and sand- 

 stones, especially in the upper beds of the system ; 

 some may represent amphibia, but the as^pciated 

 bones show that many must be ascribed to diribsaurs. 

 Bulletin 26, by Prof. V. W. Kunkel, describes the 

 existing amphipod and isopod Crustacea of the State, 

 and Dr. W. C. Britton gives a list of the insects, 

 occupying 400 pages. 



The Flotation of Continents. — Prof. Wegener's 

 \iews on continental movement were stated in a 



NO. 2745, VOL. 109] 



recent review (Nature, February 16, p. 202) of the 

 second edition of his work on " Die Entstehung der 

 Kontinente und Ozeane." His daring suggestions 

 were formulated in 191 2, and we cannot quite dismiss 

 them as Prof. L. Kober does, by saying " im Bau der 

 Erde hat die Theorie der grossen Kontinental- 

 verschiebungen keine Stiitze." However much we 

 may doubt the horizontal movement of masses of 

 " sal " across uncrumpled " sima " areas, the pro- 

 position that has arisen in the mind of a geographer 

 can be met only by argument on the part of the 

 geologist. Prof. Wegener has contributed to Discovery 

 (vol. iii. p. 114, May 1922) a lucid summary of his 

 conceptions, accompanied by maps, showing, among 

 other wonders, the transference of the Deccan to the 

 antarctic region in Carboniferous times. A polar 

 ice-cap, spreading across the conference of con- 

 tinents here cunningly arranged, would not explain 

 the movement of an ice-sheet from north to south 

 in southern Africa. Mr. A. L. du Toit, however, in 

 two notable papers dealing with former land-con- 

 nections and the glaciation of South Africa (5. African 

 Journ. Sci., vol. xviii., Dec. 192 1, and Trans. Geol. 

 Soc. S. Africa, vol. xxiv. p. 188, 1921) welcomes the 

 new hypothesis. His map of Gondwanaland as 

 promoted by flotation, with its arrows showing the 

 direction of ice-movements, seems to require a snow- 

 dome near the south of Madagascar, and a separate 

 glaciation of Australia by the polar cap. We should 

 like to study Prof. Wegener's explanation of the arid 

 climates of the Trias, and of the cold conditions 

 prevalent over the whole earth in the latest glacial 

 epoch. For him. New Zealand (see Nature, vol. 

 109, p. 657) has been left behind by the westward 

 drifting of Australia, and his " Old Quaternary " 

 map does not explain its glaciation on geographic 

 grounds. The Carboniferous map shows a general 

 submergence of Eurasia, so that his seeming repudia- 

 tion of vertical movements in accounting for changes 

 on the earth's surface may be something like the 

 waving of a red flag at the head of an orderly industrial 

 procession. We shall hope for a thorough discussion 

 of his proposals in the light of what is known as to 

 marine transgressions across the continents. 



Effect of Light on Museum Specimens. — The 

 Museums Journal for April contains a detailed 

 account by the Director of the Natural History 

 Museum of the careful experiments that he has 

 conducted there for many years, with the help of 

 the late W. G. Ridewood, on the fading of colour 

 in museum specimens. Direct sunlight is, says Sir 

 Sidney Harmer, far more injurious to colours than 

 any other method of illumination, and diffused 

 dajdight appears to produce more fading than any 

 form of electric light used. This statement applies 

 to oil-colours as well as to water-colours and the 

 colours of various animal coverings, and suggests 

 caution to those who, on the advice of Sir M. II. 

 Spielmann, would put their oil-paintings in a blaze 

 of sunlight. The various glasses designed by Crookes 

 and others to cut off the more deleterious rays were 

 not found sufficiently satisfactory to warrant the 

 expense of their installation. The practical conclusion 

 of the whole matter is that direct sunlight should be 

 avoided at all costs, and that even diffused daylight 

 should be shut out at all hours when exhibition 

 galleries are closed to the public. At other times 

 the light, if at all bright, should be moderated by 

 yellow blinds. A gallery lighted entirely by electric 

 light, preferably in the form of half-watt lamps, 

 would "have great advantages. The paper is one 

 that should be studied by all directors of museums^ 

 including art galleries. 



