458 



SGIENGE. 



[N. S. Vol. VIII. No. 197. 



' The Rotation of the Asteroids,' discussed 

 his photometric observations, extending 

 over a number of years, on planets Nos. 40 

 and 42, and from these observations con- 

 cludes that no hypothesis of rotation need 

 be introduced to account for any changes 

 in brightness. 



Dr. Herman S. Davis presented a paper, 

 read by Professor Upton, on ' The Paral- 

 laxes of 61 and 62 Cygni and the Probable 

 Physical Connection of these two Stars.' 

 From a review of the observed photographic 

 results of parallax and the apparent dif- 

 ference in parallax of the two stars, the 

 author concludes that ' these two stars are 

 moving through space independently of 

 each other and separated from each other 

 by an interval represented by two and one- 

 quarter light years;' but does not 'regard 

 this difference of parallax as an entirely 

 indisputable fact.' He, however, insists 

 that the two stars of 61 Cygni should be 

 regarded as too remote from each other to 

 form a binary system until more evidence 

 is adduced to disprove this conclusion. 



Professor Comstock said he was of the 

 opinion that the stars were at some dis- 

 tance ; considering the difference of par- 

 allax 0".08, Dr. Davis' is not the only 

 hypothesis allowable. A more plausible 

 hypothesis is that one of these stars is ac- 

 companied by a dark companion, about 

 which the star revolves so as to counteract 

 the motion of the earth. The a priori prob- 

 ability in both hypotheses is perhaps the 

 same. Professor Frisby thought that the 

 parallax determination showed overlapping 

 values not consistent with Dr. Davis' 

 hypothesis. Professor Flint pointed to the 

 large range of variation in the parallax 

 determinations of these two stars and 

 thought Dr. Davis' hypothesis unwarranted. 



Professor Charles L. Doolittle reviewed 

 the ' Work of the Flower Observatory.' 

 Double-star observations made by Mr. Eric 

 Doolittle, on a list prepared by Mr. Burn- 



ham, have been made with the 18-inch 

 telescope of Mr. Brashear. The difi&cult 

 pairs observed are a fair test of the per- 

 formance of the instrument. The theo- 

 retical power of separation is 0".275 and 

 yet in one case a pair separated by 0".24 

 has been measured. Comparing the work 

 of the Brashear instrument with similar 

 observations made by Mr. Burnham with 

 the Clark instrument of approximately the 

 same aperture at Evanston, it is found that 

 the Brashear instrument will resolve all 

 pairs shown by the Clark. Fourteen pairs 

 of new doubles have been picked up, and 

 this indicates that an ample harvest is yet 

 to be reaped. Four hundred and fifty pairs 

 have been measured on three different even- 

 ings, and the results will soon be published. 

 Professor Hough thought the results had 

 certainly shown the Brashear objective to 

 be a good one. 



A paper by Professor Arthur Searle on 

 ' Faint Stellar Bands in the Ecliptic ' was 

 read by Mr. William Maxwell Eeed. If 

 faint stellar bands exist in the ecliptic the 

 observed shape of the Gegenschein would 

 certainly be affected. Such bands Profes- 

 sor Searle has observed. The most promi- 

 nent of these extends from Aquila through 

 Aquarius and Pisces to the neighborhood 

 of Tj Tauri. Another falls close to the 

 ecliptic. It commences in Gemini and ends 

 in Coma Berenices. These bands seem to 

 be a part of a network, of faint bands that 

 cover nearly the whole sky. The Gegen- 

 schein is not always perfectly round. 



Professor S. I. Bailey, in discussing this 

 paper, said that in his observation of the 

 Gegenschein in Chile and Arequipa he had 

 never been able to see the Gegenschein per- 

 fectly circular. He suggests that the faint 

 bands might be photographed, and thus 

 their character and brightness better de- 

 termined. He had, however, not been able 

 to photograph the zodiacal light. Drawings 

 of the bands as made independently both 



