Mat 5, 1922] 



SCIENCE 



493 



or earthquake. Cooperative studies have been 

 undertaken by the Carnegie Institution of Wash- 

 ington, U. S. Coast and Geodetic Survey, TJ. S. 

 Geological Survey, the geological departments of 

 the universities of Califoruin, the California Insti- 

 tute of Technology, and the Bureau of Standards, 

 with the purpose of gathering precise data bear- 

 ing upon tills subject. It is a part of the pro- 

 gram not only to locate the surface displacements 

 either gradual or disruptive, but also to develop 

 instruments and establish stations for the location 

 of sub-surface zones of movement. 



Geological overtlirusts and underdrags: Pro- 

 fessor W. M. Davis, Harvard University (by 

 title). Overthrust masses of earth crust have 

 been found, the front of which has advanced a 

 score of miles or more beyond its original posi- 

 tion. On tracing such masses backward, no indi- 

 cations of a cavity left bj' their advance have 

 been found; hence it may be possible that they 

 have obliquely emerged from beneath rear por- 

 tions of the crust which have not taken part in 

 their movement. If so, the rear portions should 

 exhibit displacements due to what may be called 

 the "underdrag" of the obliquely emerging- 

 masses. Such displacements would be character- 

 ized by an increase in horizontal dimensions in 

 the direction of underdrag, and manifested by 

 normal faults on moderately slanting fault planes. 

 The mountain ranges of the Great Basin of Utah 

 and Nevada appear to exhibit such displacements. 



The effects of winds and barometric iiressures 

 on the Great Lakes: Dr. J. F. Hayford, North- 

 western University. The surface of the water of 

 any one of the Great Lakes is never level except 

 by accident. It always has a slope in some direc- 

 tion, produced by the wind, by barometric pres- 

 sures, or by the water of the lake oscillating as 

 if it were in a great Avash-basin. The correct 

 knowledge of these things is a key to various 

 scientific problems and ultimately will prove to be 

 worth millions, in their application, to the people 

 of the United States. It has long been knoAvn 

 that a wind blowing over a lake tends to pile up 

 the water on the lee sliore and to pull it down on 

 the windward shore. How large is this effect? 

 Is the response of the water to the wind imme- 

 diate? It has not been possible to answer these 

 questions confidently in the past. Now it is 

 known that the response is prompt and that the 

 eifeot of a given wind in disturbing the water 

 level at any point in the Avorld may be computed 

 in advance. It is known that the strongest winds 

 that blow liave almost no effect iu changing the 



water level at various points, as, for example, at 

 Milwaukee on Lake Michigan and Mackinaw City 

 on Lake Huron. On the other hand, it is known 

 that a wind of 50 miles per hour from the south- 

 west piles up the water a foot at Buffalo and 

 pulls it down simultaneously more than a foot at 

 the west end of Lake Erie. The reason for this 

 extreme contrast between different places and for 

 the fact that the wind effect is greatest in long 

 shallow bays is now accurately known. The lake 

 surface is also continually tilting up, first in one 

 direction, then in another, in response to varying 

 barometric pressures. The water tends to go 

 toward a region of low barometric pressure and 

 pile up there. Such effects at Mackinaw City and 

 Milwaukee frequently amount to three inches or 

 more, although wind effects at these points are 

 almost inappreciable. Just as a piano string 

 struck once, or the air iu an organ pipe continu- 

 ously agitated by a reed, vibrates with its natural 

 period, so the water of each of the Great Lakes 

 under the many impulses given it by the winds 

 and barometric pressures oscillates back and forth. 

 Sometimes the whole of a lake is concerned in an 

 oscillation, and sometimes the lake oscillates in 

 parts. Such oscillations in lakes are called seiches. 



Striking similarities between the igneous rocks 

 of Brazil and South Africa: Dr. H. A. Brotjweb. 

 Striking similarities in geological age and in 

 composition exist between the old granites and 

 gneisses witli intrusive younger granites, the pre- 

 cretaceous intrusive sheets of diabase, the lava 

 flows of the Serra Geral and the Drakensberg, the 

 pipes and dykes of kimberlite and the intrusive 

 and effusive alkali rocks (nephelinesyenites, phono- 

 lites, etc.). The alkali rocks are found on both 

 sides of the Atlantic Ocean near the coast; they 

 form denuded volcanic centers and if the w-est 

 coast of Africa and the east coast of South 

 America be considered in juxtaposition the loca- 

 tion of these older volcanoes Avould be very sim- 

 ilar to that of the young volcanoes of alkali 

 rocks (Kenia, etc.) near the young fracture- 

 system, bordering the rift valleys in East Africa. 

 Very long dykes of nephelinesyenites prove the ex- 

 istence of similar fractures in the central part of 

 South Africa. 



Fauna of the Pleistocene asphalt deposits of 

 McEittrick, California: Dk. John C. Merriam, 

 president of the Carnegie Institution of Washing- 

 ton, and Chester Stock, University of California. 

 The discovery of au enormous accumulation of 

 perfectly preserved remains of extinct animals 

 found in asphalt beds in the environs of Los 



