Decembee 28, 1900.] 



SCIENCE. 



1005 



SOCIETIES AND ACADEMIES. 



GEOLOGICAL SOCIETY Olf WASHINGTON. 



The 106th regular meeting was held Decem- 

 ber 12th at the Cosmos Club : 



The following papers were presented : 



Mr. C. W. Hayes. — 'The Geological Re- 

 lations of the Tennessee Brown Phosphate.' 

 Three distinct types of phosphate rock occur in 

 Tennessee, named from their prevailing colors 

 white black and brown. The white rock is a 

 recent cavern deposit ; the black rock, includ- 

 ing two varieties, nodular and bedded, is De- 

 vonian and the brown rock is Silurian. At 

 four or more distinct horizons in the lower 

 Silurian occur beds of phosphatic limestone, 

 which, on the removal of the lime by leaching, 

 yield high grade phosphate rock, containing 

 from 70 to 80 per cent, of lime phosphate. 



The recurrence of these phosphatic beds 

 through so large a portion of the Silurian and 

 Devonian formations points to a recurrence of 

 similar conditions iu Silurian and Devonian 

 time favorable for the accumulation of lime 

 phosphate. The deposits are at present lo- 

 cated along the western margin of the central 

 basin of Tennessee in a belt extending nearly 

 across the State. This belt coincides with the 

 western side of the Cincinnati anticline and a 

 genetic connection between the two is sug- 

 gested. This belt is characterized by numer- 

 ous unconformities, in part by erosion, but 

 chiefly by non-deposition. During Silurian and 

 Devonian time it was doubtless a region of 

 shallow seas protected from the incursion of 

 foreign detrital sediments. Under these condi- 

 tions the lime carbonate was perhaps removed 

 by solution nearly as fast as deposited, and the 

 lime phosphate which elsewhere is disseminated 

 through a great mass of limestones was here 

 concentrated into a relatively small volume. 



Mr. Lester F. Ward. — ' The Autochthonous 

 or Allochthonous Origin of the Coal and Coal 

 Plants of Central France.' Mr. Ward accom- 

 panied the excursions of the International Geo- 

 logical Congress to the coal basins of Commentry, 

 Decazeville and Saint Etienne, and found this 

 to be the principal geological problem pre- 

 sented. M. H. Fayol led the party through 

 the two first-named basins, and lost no oppor- 



tunity to demonstrate to the excursionists the 

 validity of his well-known theory of deltas, 

 according to which all the materials have been 

 transported from the surrounding country and 

 deposited in small lakes which have been thus 

 gradually filled up. The excursion to St. 

 Etienne was in charge of M. C. Grand'Eury, 

 whose elaborate treatment of the ' Coal Flora of 

 Central France ' is familiar to all. He was not 

 less zealous in seeking to make clear the au- 

 tochthonous origin of the coal plants of that 

 basin. Among the members of the party were 

 Dr. I. C. White, M. H. Potonie and other com- 

 petent judges of such questions. None of them 

 had an J' 'parti pris, and all were open to the 

 evidence, which, however, all admitted was in 

 certain respects more or less defective. This 

 was the fault of the conditions, and not at all of 

 the able and courteous expounders of the re- 

 spective theories. The result at least could not 

 be positively stated in favor of either theory for 

 all the beds, but M. Fayol may be said to have 

 given a correct explanation of the mode of 

 deposition of the Commentry basin and proba- 

 bly of most of that of Decazeville, although in 

 the latter the underclays certainly hold the 

 roots of plants. At St. Etienne M. Grand'Eury 

 showed the party many cases in which the finest 

 fibrils of the roots of erect Calamites were seen to 

 pass across the planes of bedding and penetrate 

 to the underlying conglomerates which formed 

 the original floor ; a condition which is wholly 

 incompatible with the theory of transportation 

 or the slightest disturbance of the plants. 



Mr. E. E. Howell. — ' A New Geological Re- 

 lief Map of the United States.' This map, ex- 

 hibited to the Society, is on a horizontal scale of 

 about 40 miles to the inch, representing a por- 

 tion of a globe 16 J feet in diameter. The ver- 

 tical scale is eight miles to the inch. The 

 geological data was obtained from the U. S. 

 Geological Survey. 



F. L. Ransomb, 

 David White, 



Secretaries. 



CHEMICAL SOCIETY OF WASHINGTON. 



A BEGXJLAB meeting was held October 11, 

 1900. The evening was devoted to the address 

 of the retiring president Dr. H. N. Stokes, on 



