114 



SCIENCE 



[N. S. Vol. XXXVII. No. 942 



versed by an electric current, was rotated 

 about its axis at uniform speed. The inner 

 armature of the condenser was then insulated 

 from the outer, after which the magnetic field 

 was annulled and the rotation stopped. The 

 inner armature was then tested for electric 

 charge. 



The second series of experiments was sim- 

 ilar to the first except that the magnetic field 

 was produced by two symmetrical electromag- 

 nets mounted coaxially with the condenser 

 and rotated together at the same speed. 



In neither series of experiments was there 

 detected upon the condenser any charge as 

 great as the experimental error (see below). 



Now it is an immediate consequence of the 

 classical experiments of Faraday and others 

 upon the electromotive force developed in a 

 metal disc rotating in a magnetic field pro- 

 duced by a fixed electric coil or magnet, to- 

 gether with experiments of Blondlot,' H. A. 

 Wilson," and myself" upon the electric charges 

 developed on adjacent conductors by the mo- 

 tion of insulators in magnetic fields produced 

 by fixed coils or magnets, that, if the complete 

 condenser and its short-circuiting wire had 

 been rotated while the coil or magnets remained 

 fixed, the armature tested would have received 

 a charge equal to the continued product of the 

 capacity of the condenser as it would be with 

 air or free ether as dielectric, the magnetic 

 flux through the space between the armatures, 

 and the number of revolutions of the con- 

 denser per second. Moreover, it follows from 

 the above mentioned experiments on insulators 

 that if the condenser's dielectric is air, as in 

 my own experiments, it is of no consequence 

 whether the air rotates with the armatures 

 or not. 



It was thus easy to calculate the charge 

 which would have been developed upon the 

 condenser in each of my experiments for the 

 same relative motion between it and the com- 

 plete field-producing agent, but with this agent 

 at rest and the condenser in motion. 



The investigation proved conclusively that 



'■Journal de Physique, 1902. 



^FUl. Trans., 1904. 



' Physical Beview, 1908. 



the condenser system, when it remained at 

 rest and the agent producing the field rotated, 

 received not more than a minute fraction of 

 the charge it would have received for the same 

 relative motion if the agent producing the 

 field had been the part to remain at rest. 

 Within the limits of error of the experiments 

 — about 1.4 per cent, in the experiments with 

 the electric coil, and about 1 per cent, in the 

 experiments with the electromagnets — this 

 fraction was zero. 



The experiments appear to be experimenta 

 crucis, in complete accord with the theory of 

 Lorentz, but inconsistent with any theory 

 based on complete relativity. 



S. J. Barnett 



The Ohio State Univeesity 



TEE AMERICAN SOCIETY OF 

 NATURALISTS 



The thirtieth annual meeting of the American 

 Society of Naturalists was held at Case School of 

 Applied Science, Cleveland, Ohio, on January 2, 

 in connection with the meetings of the American 

 Society of Zoologists, the American Association of 

 Anatomists, the Botanical Society of America, the 

 American Society of Physiologists, the American 

 Society of Biological Chemists, the American Phy- 

 topathological Society, and the various sections of 

 the American Association for the Advancement of 

 Science. 



The morning session was devoted to a symposium 

 on Adaptation, with the following speakers: 



U. M. IMtetcalf (Oberlin College): "The Origin 

 of Adaptations through Selection and Orthogen- 

 esis. ' ' 



Burton E. Livingston (Johns Hopkins Univer- 

 sity) : "Adaptation in the Living and Non- 

 living.' ' 



George H. Parker (Harvard University) : 

 "Adaptation in Animal Eeactions. " 



Henry T. Cowles (University of Chicago) : 

 "The Adaptation Viewpoint in Ecology." 



Alfred G. Mayer (Carnegie Institution of Wash- 

 ington) : "Adaptation of Tropical Animals to 

 Temperature. ' ' 



Albert P. Mathews (University of Chicago) : 

 "Adaptation from the Standpoint of the Physiol- 

 ogist. ' ' 



Lawrence J. Henderson (Harvard University) : 

 "The Fitness of the Environment; an Inquiry 



