596th ORDIXAEY GEXERAL MEETIXG, 



HELD IX COMMITTEE ROOM B, THE CENTRAL HALL, 

 WESTMINSTER, ON MONDAY, FEBRUARY 18th, 1918, 



AT 4.30 P.M. 



E. J. Sewell, Esq., ix the Chaik. 



The Minutes of ihe preceding Meeting were read iind confirmed. 

 The lecture was illustrated throughout by lantern slides. 



SUNSPOIS AND SOME OF THEIR PECULIARITIES. 

 By E. Walter Maunder, F.E.A.S., Superintendent of the 

 Solar Department, Royal Obser%-atory, Greenwich. 



MY reason for choosing Sunspots for my subject is two-fold. 

 First, the study of the spots upon the sun has been my 

 work for forty-four years ; they are the natural objects 

 with which I am best acquainted. Xext, though the subject of 

 sunspots occupies but a very small corner of the entire domain 

 of the science of astronomy, and though astronomy is but one 

 out of the large and ever-increasing number of the physical 

 sciences, yet examination of the methods employed in one 

 scientific inquiry may give some rough idea of the principles by 

 which scientific research in general is guided. 



It has passed into a proverb that Science is Measurement " ; 

 in other words, the scientific inquirer tries to throw into numerical 

 fonn the data which he collects from his observation of the 

 phenomena which he studies. There mav be much observation 

 of nature, even useful obser\-ation, but it cannot rightly be called 

 " scientific *' unless it is arranged on a svstem, is precise in 

 character, and is more or less directed towards numerical ex- 

 pression. 



Thousands of years ago, the Chinese observed and recorded 

 the appearance of spots upon the sun, but for us the history of 

 sunspots practically begins with the invention of the telescope 



