24 



SCIENCE. 



[N. S. Vol. XIX. No. 470. 



ergy per tmit of area at the surface of the 

 earth. 



The 575th meeting on December 5 was set 

 apart for the annual address of the retiring 

 president. Professor James Howard Gore. 

 His subject was ' The Geoidal Figure of the 

 Earth.' He pointed out that four views had 

 been held successively regarding the form of 

 the earth — that it was a plane, a sphere, a 

 spheroid, and a geoid; he traced the history 

 of the measurements that had led to the suc- 

 cessive views, and discussed at length the 

 present conclusions of geodesists. 



Charles K. Wead, 



Secretary. 



GEOLOGICAL SOCIETY OF WASHINGTON. 



At the 146th meeting held on November 25, 

 1903, the following papers were presented: 

 Ninth Session of the International Congress 



of Geologists, at Vienna: S. F. Emmons. 

 The Alaska-Treadwell Mine: A. 0. Spencer. 

 The Stratigraphic Position of the Judith 



River Beds: T. W. Stanton and J. B. 



Hatchel. 



The above papers have been or shortly will 

 be published in full. 



The 147th meeting of the society was held 

 on December 9. Under the title ' Notes on 

 the Deposition of , the Appalachian Pottsville,' 

 Mr. David White presented certain conclusions 

 respecting the physical geography of the Ap- 

 laohian trough during early Pennsylvania!! 

 time, with correlations based largely on the 

 study of the fossil plants. These show the 

 existence in lower Pottsville time of an axial 

 trough near the eastern margin of the present 

 coal region. The loading and subsidence of 

 this relatively nairow trough led to the sub- 

 mergence of the western land, and in late 

 Pottsville time the transgression of the sea 

 across the bituminous regions of Pennsylvania, 

 Ohio, western Maryland and northern West 

 Virginia. The thickness of the Pottsville 

 sediments, about 1,200 feet in the type section, 

 was shown to be about 4,000 feet near the 

 eastern border, in southwest Virginia near the 

 Tennessee line. 



Dr. George H. Girty made a comparison of 

 sections of upper Paleozoic rocks in Ohio and 



northwestern Pennsylvania. He showed that 

 not the Shenango sandstone, as had usually 

 been supposed, but a much lower bed in the 

 Crawford County section, was equivalent to 

 the sub-Olean conglomerate. This was de- 

 termined by tracing eastward from its typical 

 locality the Corry sandstone, which near War- 

 ren was found to occupy a position just above 

 the sub-Olean. The latter, therefore, would 

 appear to occur at about the horizon of the 

 Berea grit of Ohio, which is the same as the 

 Cussewago sandstone, which lies not far be- 

 low the Corry sandstone in Professor I. C. 

 White's section of Crawford and Erie coun- 

 ties. 



The Waverly group of Ohio was explicitly 

 included by Meek and Worthen, along with the 

 Chouteau group of Missouri and the Goniatite 

 limestone of Rockford, Indiana, in their defi- 

 nition of the Kinderhook group or epoch. The 

 only Waverly fauna well known at that time 

 was the fauna of the Cuyahoga shale, and 

 these authors seem to have had in mind as 

 the Kinderhook fauna chiefly that of the 

 Chouteau limestone. If any precise correla- 

 tion is possible between the Waverly group 

 and the early Mississippian of the Mississippi 

 valley, it lies between the middle member of 

 the Cuyahoga formation and the Chouteau 

 limestone. It follows, therefore, that the 

 series of rocks and faunas in southwestern 

 New York which overlie the true Chemung, 

 inclusive of the sub-Olean conglomerate, re- 

 cently assigned by Professor J. M. Clarke to 

 the Carboniferous, really lie below the base of 

 the Carboniferous system as at present recog- 

 nized in this country, just as they lie above 

 the Chemung beds, the recognized top of the 

 Devonian. This series, having an approxi- 

 mate thickness of 500 feet, represents an in- 

 terval not provided for in the geological time- 

 scale, and for it the term Bradfordian is pro- 

 posed. This term, which will rank with Sen- 

 ecan, Chautauquan, etc., includes the Cattar- 

 augus, Oswayo and Knapp beds of the New 

 York section, which may provisionally be ac- 

 cepted as its subdivisions. The position of 

 this series as an unrecognized interval in the 

 time-scale is quite apart from the determina- 

 tion of its age as Devonian or Carboniferous, 



