Geology and Mineralogy. 79 



was the latest publication available to him, Prof. Kossmat is non- 

 committal. In accepting the existence of large tangential forces 

 he does not accept Wegener's ideas as to the crustal movements 

 produced by them. At the close of the article there is a useful 

 bibliography. 



Geologists have been rather slow to utilize the evidence avail- 

 able from gravity observations in regard to the distribution of 

 density in the Earth's crust, evidence which began accumulating 

 when Bouguer from 1736 to 1740 made pendulum observations 

 in what is now Ecuador. One reason for the neglect of this 

 accumulating geodetic evidence has doubtless been the difficulty 

 of finding an unequivocal interpretation, but as gravity stations 

 and stations where the deflection of the plumb line is known 

 become more numerous and more densely distributed over a 

 given area, the practical range of our interpretations of this 

 evidence in terms of density, if not the range of purely specula- 

 tive mathematical possibilities, becomes more and more restricted 

 and the evidence of more real service to the geologist. Articles 

 like the present are a welcome sign that geologists are beginning 

 to realize that geodesy has evidence of value to them and that 

 compensation for every topographic feature exists in some degree 

 and must be explained by the adopted hypotheses of dynamic 

 geology. Both geologists and geodesists will find the article 

 profitable reading even though they may not accept all of the 

 author's conclusions. w. d. lambert. 



2. Publications of the United States Geological Survey, 

 George Otis Smith, Director. — Recent publications of the U. S. 

 Geological Survev are noted below: (See earlier, 3, 97-98, Jan., 

 1922.) 



Axnual Report: — Forty-second Report of the Director for 

 the year ending June 30, 1921. Pp. 108, 1 plate. — This publica- 

 tion gives in detail the work carried through by the Survey dur- 

 ing the year noted. The Director dwells in particular upon the 

 economy attained through a higher degree of efficiency. The end 

 sought for is one greatly to be desired in all departments of the 

 Government, but, unfortunately not often attained. In the case 

 of the Survey the efficiency striven for is much limited by con- 

 ditions which have already existed too long. These include 

 inadequate office quarters, restriction in the selection of person- 

 nel, small salaries and reduced appropriations for printing. The 

 total funds available for 1920-21 were $105,575. The authorized 

 expenditures were distributed as follows : For economic geology 

 of metalliferous deposits, $50,000 ; of non-metalliferous deposits, 

 $23,575; of oil, gas, coal, $110,000. Scientific researches not 

 directly economic were allotted $117,000 ; while administration, 

 salaries, etc., received $105,000. Of the total sum available for 

 geologic work, $122,000 was used for field expenses (including 



