GENERAL SUMMARY 



OP 



SCIEXTIFIC AND ESTDUSTEIAL PEOGEESS 

 DUEING THE YEAE 1873. 



ASTRONOMY. 



OuE Astronomical review for the year 1873 begins with 

 the consideration of the nebula?. Amono; those that have at- 

 tracted special attention during a number of years, the most 

 interesting is that in the great southern constellation of 

 Argo. According to the observations of Mr. Abbott, of Tas- 

 mania, during the past few years, the dark spaces in this neb- 

 ula are extending, and becoming more defined and filling up 

 with small stars, thus adding a very remarkable instance to 

 the few cases known in other portions of the heavens of rap- 

 id changes in the configuration of a nebula. 



One of the most valuable additions to the list of stellar 

 atlases is the new one. by Heis, in which the magnitude of 

 every star has been independently determined by himself, and 

 whose distinguishing feature is the delineation of the Milky 

 \Yay, so far as it is possible to see it from northern latitudes. 



Some very valuable maps have been prepared by Mr. Proc- 

 tor and others, in England, showing the distribution of the 

 stars and nebulae, from the studv of which interestino- con- 

 elusions may be hoped for. 



Among the fixed stars, the principal work of the year has 

 been, on the one hand, the continuation of the observations 

 of the southern zones by Dr. Gould at Cordoba, South Amer- 

 ica; and on the other hand, the publication by the United 

 States Naval Observatory of Yarnall's catalogue of over ten 

 thousand stars. 



The accurate observations of double stars, published from 

 time to time during the past ten years by Dembowski, have 

 seemed to him to require a corresponding and thorough in- 

 vestigation of the errors of the filarmici'ometer, and his re- 

 sults must be considered as of great value in reference to this 

 question. 



