2$2 SCIENCE PROGRESS 



brightness of faint novae and other faint variable stars ; to the 

 study of stellar clusters, and to many similar purposes. 



Astronomers have by now obtained an extensive and com- 

 paratively detailed knowledge of the region of the heavens in 

 the immediate neighbourhood of the sun. The distribution of 

 the stars, their motions in and across the line of sight, their 

 spectral types, intrinsic brightnesses, and in some cases their 

 masses are known with tolerable accuracy. A considerable 

 amount of statistical information as to the region at a somewhat 

 greater distance from the sun has also been accumulated. With 

 the new telescope, the astronomer will be able to probe yet 

 further into space, and the information which will be gathered 

 will no doubt have a profound influence on theories of the 

 structure of the Universe. This probing process with the 

 6o-inch at Mount Wilson has recently led to the formulation 

 of certain conclusions which are at considerable variance with 

 what had been generally accepted as to the structure of the 

 stellar universe, based on the study of our more immediate 

 neighbours. We congratulate Prof. Hale and his staff on the 

 possession of so fine an instrument of research, the product of 

 years of thought and work, and on having such good observing 

 conditions that they can use it with success. 



We are indebted to Prof. Hale for his kindness in forwarding 

 the photographs from which the plates which accompany this 

 article are reproduced. 



