Miscellaneous Intelligence. 251 



Americas" and "The North Atlantic as a Geological Basin" are 

 reprinted. 



Turning to the author's views on orogeny, the belief is expressed 

 that periods of mountain-making are related to the formation of 

 new land areas, the orogenic cause consisting in alternate expan- 

 sions and contractions, and being essentially that developed in his 

 volume "The Origin of Mountain Ranges," 1886. Further de- 

 tails are added, however, giving the results of laboratory experi- 

 ments upon models of various forms. These show how with 

 circumferential compression strata may be folded into parallel 

 crescentic or radiating crescentic folds with minimum mass deform- 

 ation of the beds. The resulting forms are developable surfaces, 

 made by simple bendings of the strata. An initial bias is shown 

 to be an important factor in determining the form of yielding, 

 and the whole is an important contribution showing the effects 

 of compression acting in two or more directions simultaneously. 



While Reade has demonstrated the adequacy of repeated ex- 

 pansions and contractions in producing deformations in several 

 substances, notably to the distortions of a lead-lined sink, to the 

 reviewer's mind it is far from being demonstrated quantitatively 

 sufficient to result in mountain-making, chief among the objec- 

 tions being first, that there is no -evidence of the numerous wide- 

 spread fluctuations of internal temperature which would be neces- 

 sary for the amount of shortening shown in the chief mountain 

 ranges ; secondly, that the unequal heating of higher and lower 

 beds would result in differential movement and friction in trans- 

 mitting the thrust to a distance, lessening the effective thrust of 

 the expanding stratum and tending to produce local vertical mass 

 deformation rather than distant folds. Thirdly, this theory does 

 not account for the deferment of mountain-making for millions 

 of years, during which time progressive sedimentation and sub- 

 sidence is going forward, followed by a relatively brief epoch of 

 crustal yielding. 



In the latter part of the book the author devotes two chapters 

 to faulting and to slaty cleavage. j. b. 



III. Miscellaneous Scientific Intelligence. 



1. Smithsonian Institution, S. P. Langley, Secretary, Report 

 for year ending June 80, 1903. — The annual report of the Smith- 

 sonian Institution gives a summary of the work done in the several 

 fields of activity. In the appendixes to the general report 

 are more detailed statements regarding work of the National 

 Museum, the Bureau of Ethnology, etc. The Museum is to have 

 a 83,500,000 building in which its large and rapidly increas- 

 ing collections may be properly stored. The Astrophysical 

 Observatory has made special holographic studies of the absorp- 

 tion of the solar rays. The atmosphere " has been more opaque 

 than usual within the present calendar year, so much so as to 

 reduce the direct radiation of the sun at the earth's surface by 

 about 10 per cent throughout the whole visible and infra-red 

 spectrum, and by more than double this amount in the blue and 



