CONTENTS. 



Page 



Art. XII. — 27-Day Auroral Period and the Moon ; by H. H. 



Clayton :.. 81 



XIII. — Combination Tones of the Siren and an Organ Pipe ; 



by C. Barus T *. _ 88 



XIY. — Some Products found in the Hearth of an Old Fur- 

 nace upon the dismantling of the Trethellan Tin Works, 

 Truro, Cornwall ; by W. P. Headden 93 



XV. — Kant as a Natural Philosopher; by G. F. Becker 97 



XVI. — Islands and Coral Reefs of the Fiji 'Group; by A. 



Agassiz 113 



XVII. — Simple Compensated Shunt Box ; by W. M. Stine. 124 



XVIII. — Mineralogical Notes on Cyanite, Zircon, and Anor- 



thite from North Carolina ; by J. H. Pratt . . 126 



XIX. — Source of the X-Rays ; by J. Trowbridge and J. E. 



Burbank 129 



XX. — Four New Australian Meteorites; by H. A. Ward .'. 135 



XXI. — Measurement of Self-Inductance by Alternating Cur- 

 rent and Electrodynamometer ; by K. E. Guthe 141 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Influence of Proximity on Voltaic Action, Gore: Action 

 of Light on Chlorine and Hydrogen, Gautier and Holier, 144. — Series Spectra 

 of Oxygen, Sulphur and Selenium, Rcnge and Pasci-ien, 145. — Production of 

 Electricity by Chemical Means, Andreas: Graphite, Graphitite and Graphitoid, 

 Weinschenk, 146. — Manuel d' Analyse Chimique appliquee a TExamen des 

 Produits Industriels et Commerciaux, E. Fleurent: Organic. Chemistry for the 

 Laboratory, W. A. Noyes, 147. — Deductive Physics, F. J. Rogers: Modes of 

 Motion ; or Mechanical Conceptions of Physical Phenomena, A. E. Dolbear : 

 Electrical Wind, S. Arrhenius : Heat produced by the Rontgen ray s, E. Dorn, 

 148. — Effect of Cathode rays on air, P. Lenard: Electric arc bet ween alumi- 

 num electrodes, V. v. Lang : Stratified discharges of electricity in free air, 

 M. Toepler, 149. 



Geology and Natural History — Geology of Johnson County, Iowa, S. Calvin, 149. 

 — Iowa Geological Survey ; Annual Report, 1896, S. Calvin: La face de la 

 Terre (Das Antlitz der Erde), E. Suess: Boletin del Instituto Geologico de 

 Mexico. J. G. Aguilera, 152. — Zirkelite. M. E Wadsworth: Krystallograph- 

 sche Winkeltabellen, V. Goldschmidt, 153. — Tabellarische Uebersicht der 

 Mineralien nachj'hrer krystallographisch-chemischen Beziehungen geordnet, 

 P. Groth, 154.— Mmeralogie de la France et de ses Colonies, A. Lacroix: 

 Description of Minerals of Commercial Value, D. M, Barringer: Complete 

 Catalogue of Minerals, W. M. Foote, 155. — Synoptical view of the various 

 divisions of Embryophy ta siphonogama ; A. Engler, 156. 



Miscellaneous Scientific Intelligence — Scientific Collections presented to Yale Uni- 

 versity, 0. C. Marsh. 156.— Smithsonian Institution, 1846-1896, 158.— Wiede- 

 mann's Annalen, Jubelband: Untersuchung uber die Bahn des Cometen. 1822, 

 IV, A. Stichenoth: Problems of Nature, researches and discoveries of Gustav 

 Jaeger, M.D., selected from his published writings: Verzeichuess sammtlicber 

 Preparate, Drogen und Mineralien mit Erlauterungen, 1897, 160. 



Obituary— Dr. Albrecht Schrauf. 



