424 SCIENTIFIC RECORD FOR 1883. 



t 



ranged by Mr. George B. Clark, and at present the transit of stars of 

 the tenth, and even of the eleventh, magnitude can be observed. 



The successful working of the meridian photometer is remarked upon, 

 and it is stated that since November 1, 1882, there have been made 133 

 series of observations of this kind, which required about 20,000 settings. 

 The most important investigation made with the instrument relates to 

 the magnitudes of the brighter telescopic stars in the northern hemis- 

 phere. This will result in reducing to a single system the estimates of 

 brightness made at thirteen observatories for ten or fifteen years, during 

 the recent co-operative zone observations. It appears from the work of 

 the meridian photometer that systematic errors in previous estimates of 

 magnitude have occurred, owing to the presence of the Milky Way and 

 of groups of bright stars, especially those in Orion. The equatorial of 

 the west dome has been actively employed by Mr. Chandler especially 

 in the study of the variable stars. About one hundred and forty vari- 

 ables of long period are definitely known to exist, and each of these 

 objects is observed twice a month, according to the present plan of 

 work, and still more frequently during its brighter phases. About 

 three hundred observations of the color of variable stars have also been 

 made, and telescopic stars suspected of variability are likewise exam- 

 ined. Important experiments in astronomical photography have been 

 made. It is thought that photographic methods will furnish very deli- 

 cate tests of the color of stars, and a photographic map of the whole 

 heavens is to be formed. 



A congratulatory reference is made to the adoption of the new stand- 

 ard time, in respect to which it is remarked that the policy of the ob- 

 servatory has been to avoid forcing the matter in anticipation of the 

 public wishes. The Boston time-ball was dropped during the year at 

 noon by telegraph on 321 days, and by hand on 40 days. On 4 days it 

 failed to fall at noon, but was dropped five minutes later. The transfer 

 of the Smithsonian Institution to the observatory of the responsibility 

 of collecting and distributing intelligence of new discoveries is noted as 

 one of the important events of the year. Among other matters the 

 successful observations of the transit of Venus last December are men- 

 tioned. • The report closes as follows: 



u The director visited Europe during the summer, and, among other 

 scientific results of his trip, obtained copies of valuable unpublished 

 manuscripts of Sir William Herschel and of Argelander. The Herschel 

 manuscripts complete the estimate of the light of all stars in Flam- 

 steed's Catalogue, and are of great importance in connection with the 

 work of the meridian photometer. Thirty-one publications relating to 

 science have been made during the year by the observatory or its officers 

 individually." (Boston Advertiser.) 



From the last annual report of Harvard College Observatory we learn 

 that the search for new planetary nebula} (by the spectroscopic method) 



