NOTES BY THE EDITOR. XV 



similar circumstances, the less their temperature and the greater 

 their mass is. 



6. The great difference of intensity in the dark lines of the 

 spectrum of the sun and other fixed stars depends not only on 

 the differences of absorption, but also on the different depths at 

 which the reversion of the spectra takes place. 



M. Borelly, at the Marseilles Observatory, has discovered a new 

 planet (No. 110). Professor Peters, of Hamilton College, has 

 added two new asteroids (the 111 and 112) to the number 

 already enrolled. A new comet was discovered at the observa- 

 tory of Marseilles, on the 28th of August, by M. Coggin. 



Professor Winlock, of the Cambridge Observatory, has had pho- 

 tographs of the sun taken nearly every fair day during the past 

 year. The primary objects in this work have been to prepare 

 and perfect apparatus and processes which might be used with 

 the best result during the coming transit of Venus, in 1874. A 

 reliable record of changes in the sun's surface is also obtained 

 by these photographs. 



Mr. Proctor has published some novel views of the constitution 

 of the stellar system under the title of " Star Drift" and " Star 

 Mist." 



Dr. Gould, with assistants, is now stationed at Cordova, in the 

 Argentine Confederation, having the observatory there under 

 his charge. He proposes to extend the catalogue of the south- 

 ern heavens beyond the limit of 30, to which the zones of Arge- 

 lander extended. Dr. Gould says, "My hope and aim is to 

 begin a few degrees north of Argelander's southern limit, 

 say at 26 or 27, and to carry southward a system of zone 

 observations to some declination beyond Gilliss 1 northern limit, 

 thus rendering comparisons easy with both these other labors, 

 and permitting the easy determination of the corrections need- 

 ful for reducing positions of any one of these three series to cor- 

 responding ones for the other." 



Great preparations were made to observe the total eclipse of 

 the sun in December, Professor Pierce, of Harvard College, in 

 his official capacity as superintendent of the coast survey, having 

 general charge of the American expedition. 



After crossing the Atlantic Ocean, the shadow of the moon 

 passed across the south of Portugal and the Straits of Gibraltar to 

 Algeria, reaching its most southerly limits in about longitude 4 

 east of Greenwich, where the southern boundary of the shadow- 



