CONTEN T S . 



Pa#c 



Art. XXVII. — Compressibility of Colloids, with Applica- 

 tions to the Jelly Theory of the Ether; by C. Barus .. 285 

 XXVIII— Eolian Origin of Loess; by C. R. Keyes 299 



XXIX. — Dikes of Felsophyre and Basalt in Paleozoic Rocks 

 in Central Appalachian Virginia ; by N. H. Darton 

 and A. Keith ._ , . _ 305 



XXX. — Diaphorite from Montana and Mexico; by L. J. 



Spencer 316 



XXXI. — Detection of Sulphides, Sulphates, Sulphites and 

 Thiosulphates in the presence of each other ; by P. E. 

 Browning and E. Howe 317 



XXXII. — Twinned Crystals of Zircon from North Carolina; 



by W. E. Hidden and J. H. Pratt _ . . 323 



XXXIII.— Brachiopod Fauna of the Quartzitic Pebbles of 

 the Carboniferous Conglomerates of the Narragansett 

 Basin, R. L; by C. D. Walcott 327 



XXXIV. — Origin and Significance of Spines; A Study in 



Evolution; by C. E. Beecher 329 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Neon and Metargon, companions of Argon in Atmos- 

 pheric Air, Ramsay and Travers, 360. — Metargon, De-war: Density and Boil- 

 ing Point of Liquid Hydrogen, Dewar, 361. — Boiling Point of Liquid Ozone, 

 Troost. 362. 



Miscellaneous Scientific Intelligence — American Association for the Advancement 

 of Science, 363. —British Association, 372. 



