\ 1 CONTENTS. 



Number 2 68. 



Page 



Art. XVII. — The Failure of Cavities in Crystals and Rocks 



under Pressure; by P. W. Bktdgman 243 



XVIII. — Stress-Strain Relations in Crystalline Cylinders; by 



P. W. Bridgman 269 



XIX. — Influence of a Series Spark on the Direct Current 



Corona; by S. J. Crooker , 281 



XX.— The Ternary System MgO-Al,0 3 -SiO a ; by G. A. 



Rankin and H. E. Meewjn 301 



Abbe Rene Just Hatty, with portrait (frontispiece) 326 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Solubility of Pure Radium Sulphate, S. C. Lind, 

 J. E. Underwood and C. F. Whittemore: Specific Heats at Low Tempera- 

 tures of Several Metals, E. D. Eastman and W. D. Rodebush, 327. — 

 Reagents and Reactions, E. Tognoli, 328. — Treatise on Applied Analytical 

 Chemistry, V. Villavecchia: Motion of a Spinning Projectile, J. Pres- 

 cott. 329. —New Secondary Radiation of Positive Rays, M. Wolfke, 331. — 

 A Textbook in Principles of Science Teaching, G. R. Twiss, 332. 



Geology — Fauna of a Medial Tertiary Formation and the Associated Horizons 

 of Northeastern Mexico, R. E. Dickerson and W. S. W. Kew ; Climate 

 and its Influence upon the Oligocene Faunas of the Pacific Coast, R. E. 

 Dickerson, 332 ; Orbitoid Foraminifera of the Genus Orthophragmina 

 from Georgia and Florida, C. W. Cooke and J. A. Cushman: Summary of 

 Geological Results, 0. Holtedahl, 333. — Paleontology of the Oligocene of 

 the Chehalis Valley, Washington, K. E. H. Van Winkle : Papers from 

 the Geological Department, Glasgow University: New generic names for 

 Upper Cretaceous Gastropoda, Bruce Wade, 334. 



Miscellaneous Scientific Intelligence — Principles of Economic Zoology, L. S. 

 Daughertt and M. C. Daugherty : The Conduction of the Nervous 

 Impulse, K. Lucas: A Text-book of Mycology and Plant Pathology, J. W. 

 Harshberger: Italian investigations in Oceanography, 335. — Publications 

 of the Allegheny Observatory of the University of Pittsburgh: Publica- 

 tions of the Cincinnati Observatory: Third Melbourne General Catalogue 

 of 3068 Stars for the Equinox 1890, P. Baracchi, 336. 



