January 24, 1913] 



SCIENCE 



157 



Professor James F. Abbott, of Washington 

 University, addressed the academy on "Permea- 

 bility of Animal Membranes, ' ' dealing particu- 

 larly with some experiments conducted during the 

 summer on fiddler crabs. 



Dr. G. H. Turner, of the Sumner High School, 

 gave a short talk on "The History of an Orphan 

 Colony of a Paper-making Wasp ' ' ; and Dr. H. M. 

 Whelpley spoke on ' ' Indian Miniature Axes and 

 Celts," illustrating his remarks with numerous 

 interesting examples. 



Professor F. E. Nipher, of Washington Univer- 

 sity, presented some results of his experiments on 

 "The After Effects in an Aluminum Wire used 

 in Electric Discharge. ' ' 



Since making a communication to the Academy 

 of Science of St. Louis on November 4, experi- 

 ments have been made in the study of the creeping 

 of an aluminum wire through which a rarefaction 

 wave is sent. 



When a fresh wire is used, the wire creeps in a 

 direction opposite to that of the corpuscular dis- 

 placement. 



After the discharges from a condenser of large 

 capacity have passed through the wire for fifteen 

 ot twenty minutes the position of the wire is re- 

 versed; no other change being made, the wire 

 creeps in the opposite direction in space. This has 

 been repeated many times. 



On the other hand, if the polarity of the influ- 

 ence machine is reversed the wire creeps in the 

 same direction in space. 



The end of the wire which is in advance in the 

 motion of the first case is in advance in the two 

 subsequent cases. 



In the two latter cases the wire creeps toward 

 the positive terminal. The discharge terminals at 

 the wire were in the form of rings of large copper 

 wire, which closely encircled the aluminum wire. 

 The long spark was in the conductor leading to 

 the positive terminal of the machine, about ten 

 feet distant. Some preliminary experiments seem 

 to indicate that this after-effect can not only be 

 eliminated, but that it can be reversed. 



Such effects have not been observed in copper 

 wires, but it is possible that a decrease in the sensi- 

 tiveness of response of the wire was due to this 

 cause, and not to frictional contact in the grooved 

 supports, as had been supposed. It was at first 

 thought that the effects described might be explained 

 as differential end or point reactions between the 

 ends of the wire and the air and other surrounding 

 matter. The ends of the wire were, however, bent 



downward, so that they point in a direction at 

 right angles to that in which the wire creeps. 

 Either end may be bent downward, the other 

 pointing either in the direction of motion, or in 

 the reverse direction, without affecting the direc- 

 tion in which the wire creeps, in any material way. 

 This apparently eliminates end effects from any 

 part in these very remarkable results, and it is 

 entirely possible that some of the conclusions here- 

 tofore published may require modification. 



It would not be surprising, in view of these 

 results, to learn that the resistance of this wire 

 depends upon the direction of flow of the current. 

 George T. Moore, 



Secretary 



THE BOTANICAL SOCIETY OF WASHINGTON 



The 83d regular meeting of the society was 

 held at the Cosmos Club November 12, 1912. The 

 program included the following papers: 

 A Portrait of Linnwus: Dr. J. N. Rose. 



Dr. Rose exhibited an engraved portrait of Lin- 

 nsus which had recently been presented to the 

 Smithsonian Institution by Captain John Donnell 

 Smith, of Baltimore, who had previously given to 

 that Institution his magnificent herbarium and 

 library. This portrait is one rarely seen in this 

 country, being a mezzotint of one of the earliest 

 portraits of Linnffius, the original being a replica 

 of Hoffman's famous picture showing Linnaeus in 

 Lapland dress, of which the original is now the 

 property of the Clifford family. This replica was 

 known to have been in the possession of one 

 Thornton as late as 1811 ; but its whereabouts now 

 is not known. 



Dr. Rose also called attention to the large col- 

 lection of portraits of Linnseus in the possession 

 of the Linnean Society, and also to the work of 

 Tycho Tullberg, " Linneportratt, " a quarto vol- 

 ume of 185 pages with 25 portrait plates. 

 "Bough-'barlc" Disease of the Tellow Newtown 



Pippin: Mr. John W. Roberts. 

 Botanizing in the Begion of the Natural Bridges 



of Southeastern Utah: Dr. P. A. Rydberg (by 



invitation). 



The 84th regular meeting was held at the Cos- 

 mos Club on December 3, 1912. The program 

 included the following papers: 

 Summary of Studies of Glomerella (with lantern) : 



Dr. C. L. Shear. 

 Frohable Origin of Maize (with lantern) : Mr. G. 



N. Collins. 



