SCIENCE. 



259 



verified by actual returns to perihelion, the question of 

 periodicity cannot be affirmed with positiveness. Every 

 few years a new one is added to the list, but during the 

 centuries and milleniums which are to come, the number 

 must swell to thousands. 



Prof. Chandler is computing a new set of elements 

 from more trustworthy data, but, as the comet is running 

 well with those first published, the new set will probably 

 differ but little from the first. The discovery of this 

 comet was immediately cabled to Europe, and I have 

 received official announcement that the cablegram was 

 duly received, but it seems that it was not discovered 

 there until November 7, when, not knowing but it might 

 possibly he a new one, it was cabled here as such. 



It has never, to my knowledge, been published in this 

 country, that the Vienna Academy has rescinded its offer 

 of prizes for the discovery of comets ; therefore I expect 

 no gold medal for the discovery of this, but your readers 

 may be surprised, perhaps pleased, to learn that Mr. H. 

 H. Warner, the well-known medicine man, who is build- 

 ing the new observatory for my use, gave me his check 

 for $500 for its discovery. This, together with the three 

 gold medals awarded me by the Imperial Academy of 

 Sciences of Vienna, is a partial remuneration for the 

 labor and the unknown suffering endured from cold and 

 want of sleep during the many years I have followed 

 comet seeking in the open air, with no protection from 

 the piercing winds of our northern winters. 



The following are a few positions of the comet from 

 Chandler's ephemeris for Washington midnight. 



h. m. s. 



November 20 1 9 18 Dec. + 54 3 



24 2 6 19 54 25 



28 2 58 39 S3 3 



Lewis Swift. 



Rochester, Nov. 17, 1880. 



COMET E 1880. 



This comet, discovered by Mr. Swift on October ioth, 

 proves to be an interesting object. An orbit has been 

 computed by Mr. Winslow Upton, of the Naval Observa- 

 tory, from the observation made here by Professor East- 

 man, and there can be no doubt that this is a return of 

 the comet discovered by Mr. Tempel, November 27, 1869, 

 since the elements of the two orbits are very nearly alike. 

 The periodic time of this comet is therefore nearly eleven 

 years, and its mean distances from the sun is a little less 

 than that of Jupiter. A. Hall. 



Washington, Nov. ii, 1880. 



ASTRONOMICAL NOTES. 



The corrections employed in reducing the double star 

 observations of M. Otto Struve, given in Vol. IX., of the 

 Poulkova observations were only provisional. Since the 

 publication of that volume definitive corrections have been 

 computed by M. Dubiago, and the corrected results are 

 now published as an appendix. 



At the meeting of the American Association this 

 Summer, Professor Stone gave a description of the con- 

 tinuation of Argelander's Durchmnsterung now " in 

 progress at the Cincinnati Observatory. The zone will 

 extend from 23° to 31" south declination. A four inch 

 equatorial is employed. 



Part III of the Astronomical Papers prepared for 

 the use of the American Ephemeris and Nautical 

 Almanac is devoted to Master Michelson's determination 



of the velocity of light. A minute description of the 

 apparatus employed is given, together with the deter- 

 mination of the errors to which the observations were 

 subject. In the latter part of the work several objections 

 to the plan followed by Foucault are considered. 



Vol. VI, of the Annates de I ' Observatoire de Moscow 

 contains an interesting series of observations of Jupiter 

 made during the opposition of 1879. Nearly forty draw- 

 ings are given, twenty-seven of which were made at 

 times when the large red spot was visible. 



An attempt to photograph stellar spectra was made 

 by Drs. Huggins and Miller, as long ago as 1863, but 

 not with the best of success. Dr. Huggins has 

 published in the last volume of the Philosophical Trans- 

 actions, the results of a recent, and this time successful, 

 attempt, and at the end of the paper has given a map 

 of the spectra of several of the stars observed. These 

 are a Lyrae, Sirius, n Ursae Majoris, a Virginis, a 

 Aquilae, a Cygni, and Arcturus. With the exception 

 of the latter these are all white stars and were observed 

 on account of the remarkable circumstance of the 

 absence of the K line in one of the earlier photographs 

 of Sirius. "The photographs present a spectrum of 

 twelve very strong lines. Beyond these lines a strong 

 continuous spectrum can be traced as far as S, but 

 without any further indication of lines. The least 

 refrangible of these lines is co-incident with the line (C) 

 of hydrogen near G. The next line in order of greater 

 refrangibility agrees in position with h of the solar 

 spectrum. The thirdl ine is H, K, if present at all, is 

 thin and inconspicuous. The nine lines which follow do 

 not appear to be co-incident with any of the stronger 

 lines of the solar spectrum." The symmetry of arrange- 

 ment of these lines is such as to suggest that they are 

 the spectrum of a single substance, perhaps hydrogen. 



The spectrum of Arcturus is very different from that 

 of the other stars named, but quite similar to that of the 

 sun. The spectrum is crowded with a vast number of 

 fine lines, and in further contrast with the class of white 

 stars the hne K is very broad and winged and more in- 

 tense than H. Beyond K the lines are broader and 

 more intense and arranged more or less in groups with 

 fine lines between. Although the crowding continues as 

 far as the spectrum can be seen on the plate the position 

 and arrangement of the lines beyond H is quite different 

 from those in the solar spectrum. 



Photographs of the spectra of Venus, Mars and 

 Jupiter were also taken, but these showed no modification 

 whatever of the solar light. In the case of the moon 

 most of the photographs presented differences in the 

 relative intensity of the ultra violet region, but nothing 

 that could be taken as evidence of the existence of a 

 lunar atmosphere. O. S. 



Prof. C. A. Young, of Princeton, has been fortunate 

 enough to obtain one of the finest large-crown glass 

 discs ever cast. It is of French manufacture, 22 inches 

 in diameter and without a flaw. Alvan Clark & Sons 

 are finishing it for the new Princeton refractor. 



Dr. B. A. Gould, Director of the Cordoba Observatory, 

 Argentine Republic, was in Boston, November 3, on a 

 visit to this country and returns to Cordoba on the 

 steamer of the 27th November. His address is no 

 Marlboro street, Boston. 



Dr. Elkin, whose work on the Parallax of a Centauri 

 has been previously noticed, is spending a few weeks in 

 Washington. He expects to leave shortly for the Cape 

 of Good Hope, where he will continue his investigations 

 upon the Parallax, using for that purpose Lord Lindsay's 

 four-inch Heliometer, which he is to take out with him. 



W. C. W. 



