VI CONTENTS. 



Number 82. 



Page 

 Art. XXIX. — Experimental Investigation into the Existence 

 of Free Ions in Aqueous Solutions of Electrolytes ; hj 

 J. Olsen _ 237 



XXX. — Solution of Problems in Crystallography by Means 

 of Graphical Methods, based upon Spherical and Plane 

 Trigonometry; by S. L. Penfield _ 249 



XXXI. — Estimation of Bromic Acid by the Direct Action of 



Arsenious Acid; by F. A. Gooch and J. C. Blake 285 



XXXII. — Solubilities of Some Carbon Compounds and Densi- 

 ties of their Solutions ; by C. L. Speters ._ 293 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Eadio-active Bisnmtli, Marckwald : Thermoclieini- 

 cal Constant, F. W. Clarkk, 303. — Heatless Condition of Matter, Brink- 

 worth and Martin, 304,— Elementary Chemistry, by F. W. Clarke and 

 L. M. Dennis : Liquid Hydrogen and Helium, J, Dewar, 305. — Vapor- 

 pressures of Liquid Oxygen and of Liquid Hydrogen, M. W. Travers, 

 G. Senter and A. Jaquerod, 311. 



Geology and Mineralogy— MsLvtinique, 312. — Eeportof tlie Geological Survey 

 of Louisiana, G. D. Harris, A. C. Veatch and J. Pacheco, 314. — Alpen 

 im Eiszeitalter, A. Penck and E. Bruckner, 315. — Bacubirito, the Great 

 Meteorite of Sinaloa, Mexico, H. A. Ward : Origin of Eskers, W. O. 

 Crosby : Ueber Hussakite (Xenotim) und einige andere seltene gesteins- 

 bildende Mineralien, H. Eosler, 316. 



Miscellaneous Scientific Intelligence — International Catalogue of Scientific 

 Literature, 317. — British Association : Experiments in Aerodynamics, 

 S. P. Langley : Elementary Physical Geography, W. M. Davis : Inter- 

 national Quarterly, 318. 



Obituary — Professor Eudolf Virchow. 



