2 ANNUAL EECORD OF SCIENCE AND INDUSTRY. 



been devoted to it by Professor Yarnall and his assistants, 

 and he has himself made nearly one half of the observations. 

 The catalogue is based on over eighty thousand observations 

 of more than ten thousand stars, many of them being quite 

 faint, and in extreme southern latitudes, such as have never, 

 or rarely, hitherto been observed. 



Professor Yarnall has made an elaborate comparison of 

 his results with the position of the stars given in the Ameri- 

 can Nautical Almanac^ and finds that but very small syste- 

 matic differences exist. Americans will be pleased to wel- 

 come this valuable addition to astronomical literature. 



AMATEUR ASTRONOMY IN AMERICA. 



Mr. C. W. Burnham, of Chicago, has communicated to the 

 London Astronomical Society a list of eighty-one new double 

 stars discovered by him. Mr. Burnham is an amateur astron- 

 omer one of the few in this country who have succeeded in 

 bringing their enthusiasm up to the " useful-work " point. 

 He has consulted almost all the good modern catalogues of 

 double stars in order to ascertain that those discovered by 

 him to be double were not already recorded in the annals of 

 astronomy. Chicago is to be congratulated that, amid her 

 business and her losses, one of her citizens is able to apply 

 his leisure to the j^ursuit of so ennobling a study. 



THE VARIABLE SIZE OF THE SUN. 



Secchi, the astronomer of Rome, has concluded, from cer- 

 tain observations made during the past year, that he is justi- 

 fied in affirming that there is a periodic variability in the size 

 of the sun. The many startling revelations of science during 

 the past ten years have j^repared the way for the acceptance 

 of even this conclusion, though the observations on which 

 Secchi founds his belief are as yet so few as to still leave room 

 for some possible doubt on the subject. It would seem that 

 the outer surface of the sun the photosphere as seen by us 

 is a gaseous envelope in a state of continual and perhaps 

 periodic change, such that the diameter of the solar orb, as 

 measured by the aid of the telescope, is least in the region 

 of the greatest spot activity that is, the solar equatorial 

 belt does not bulge out as does that of the earth, but, on the 

 contrary, the solar polar axis is the longest diameter of that 



