CONTENTS. 



Number 266. 



Page 

 Art. X. — Isothevmals, Isopiestics and Isometrics relative to 



Viscosity; by C. Barus .. 87 



XI. — "Potential" a Bernoullian Term; by G. F. Becker.. 97 

 XII. — Datolite from Loughboro, Ontario; by L. V. Pirsson LOO 

 XIII. — New Machine for Cuttingf and Grinding: thin sections 



of Rocks and Minerals ; by G. H. Williams 1 02 



XIV. — Stannite and some of the Alteration Products from 



the Black Hills, S. D.; by W. P. Headden 105 



XV. — Occurrence of Hematite and Martite Iron Ores in 



Mexico ; by R. T. Hill ; with notes on the associated 



Igneous Rocks ; by W. Cross u 111 



XVI. — Ca3sium-Lead and Potassium-Lead Halides ; by H. L. 



Wells 121 



XVII. — Ceratops Beds of Converse County, Wyoming ; by 



J. B. Hatcher 135 



XVIII. — Use of Planes and Knife-edges in Pendulums for 



Gravity Measurements ; by T. C. Mendenhall 144 



XIX. — Preliminary note on the colors of cloudy condensa- 

 tion ; by C. Barus 150 



XX. — Lines of structure in the Winnebago Co. Meteorites 



and in other Meteorites; by H. A. Newton 152 



XXI. — Preliminary Note of a new Meteorite from Japan ; 



by H. A. Ward 153 



Appendix. — XXII. — Restoration of Anchisaurus; by O. C. 



Marsh. (With Plate VI) 169 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Re-conversion of Heat into Chemical Energy in the 

 production of Gas, Naumann, 155. — Temperature of Ignition of Electrolytic 

 Gas, Freyer and V. Meter: Electromotive Activity of the Ions, Nernst and 

 Pauli, 156. — Separation of Precipitates at the Surface bounding Electrolytes, 

 Kummell: Chemical Phenomena at low Temperatures, Pictet, 157. — New 

 Telephotographic lens, T. K. Dallmeyer: Oxygen for lime light, T. C. Hep- 

 worth. 158. — Interference of Electric Waves: Explanation of Hall's phenom- 

 enon, E. Lommel: Mercury Voltaic arc. H. Avon, 159. 



Geology and Natural History — North American Fossil Mammals, 159. — Geology 

 of the Eureka District, A. Hague, 161. — Geological Survey of Alabama, E. A. 

 Smith: Geological Atlas of the United States. Chattanooga sheet, Tennessee: 

 North American Continent during Cambrian Time, C. D. Walcott: Lafayette 

 Formation, W. J. McGee: Origin and Nature of Soils, N. S. Shaler, 163. — 

 Cambrian Fossils of New Bruuswick, G. F. Matthew : Experiments in Physical 

 Geology, E. Reyer: Brief notices of some recently described minerals, 164. — 

 Large Variations in the Metamorphosis of the same species, W. K. Brooks and 

 F. 11. Herrigk, 166. — Morphologische Studien, K. Schumann, 167. 



Miscellaneous Scientific Intelligence — Bulletin from the Laboratories of the State 

 University of Iowa: Astronomical Journal Prizes: Ostwald's Klassiker der 

 Exakten Wissenschaften. 168. 



