64 PROCEEDINGS OF THE AMERICAN ACADEMY 



though the number of gray spots varies but little in different latitudes, 

 in general the spots become larger and more com})licated as they 

 approach the equatorial zones. 



The most marked characteristic of the gray spots is their vagueness 

 of outline. They are never sharply defined like ordinary spots, but 

 they appear blurred and diffused like an object seen through a mist. 

 As I shall endeavor to show presently, these objects are really seen 

 through the chromospheric gases which are spread as a veil over them, 

 causing this vagueness of outlines. For this reason, I jiropose for them 

 the name of Veiled Solar Spots. 



The veiled solar spots, especially in the lower latitudes, have a 

 remarkable tendency to assemble into small groups after the manner of 

 ordinary spots. Sometimes three or four are seen in contact, while 

 there are comparatively large intervals where none are to be seen. I 

 have in several instances seen the actual formation into groups of 

 distinct veiled spots. 



The granulations of the chromosphere are seen projected upon the 

 veiled spots, just as anywhere else, but they are not there so regularly 

 distributed ; some being closely crowded together, while others are 

 widely scattered. Small facula^ are often formed in this manner by the 

 aggregation of several granules into one mass. Once in a while, the 

 granulations appear as if they were under the power of a propelling 

 force by which they arrange themselves in files, and sometimes in 

 capricious figures which are very remarkable. 



• In many cases I have observed that the granulations projected 

 upon the veiled spots have an extraordinary mobility, to be seen 

 nowhere else, except perhaps in the immediate vicinity of ordinary 

 spots in full activity. Often their form and position are totally 

 changed within a few minutes, and sometimes even within a few sec- 

 onds. This was especially the case June 21. At 8h. 30m. on that 

 day, I was observing a group of veiled spots not far from the centre 

 of the sun, when my attention was drawn to the extraordinary mo- 

 bility of the granulations covering this group. In an instant they 

 changed their form and position, some crowding together as though 

 briskly attracting each other, while others would fly apart as if 

 repelled by an invisible force. Under this tumultuous conflict of 

 forces, new veiled spots would appear and disappear in an instant, 

 faculaj would form and vanish ; in. fact, all was in motion and con- 

 fusion on that particular part of the sun. It was evident that im- 

 mense forces were in conflict under the chromosphere. 



At 2h, Om. P.M., on the same day, several small black spots had 



