Page:Popular Science Monthly Volume 24.djvu/193

Rh in it; there was the great spot, often of singular outline, accompanied outside its shadowy borders by one or more swarms of minute black specks pitting the white photosphere in the most extraordinary fashion; there was the huge group, visible even to the unassisted eye, and consisting of half a dozen or more large spots intermingled with smaller ones whose number seemed to defy counting, and enveloped in a penumbral cloak of becoming amplitude; there, near the edges of the disk, were the crinkling lines and heaped-up masses of faculæ, the mountainous hydrogen-flames which marked the places where the intensest solar action was going on—in short, there was a panorama in which every variety of sun-spot seemed to be passing in a gigantic procession across the disk. And what a procession it was!—long enough, nearly, to reach from the earth to the moon and back again three times!

But the most extraordinary feature of this great solar display was the linear arrangement of the spots making a belt, or band, that half encircled the sun; there was also a noticeable regularity in the distances separating the groups composing this singular belt, and this peculiarity increased the likeness to a procession which must have impressed every observer who beheld the gradual march of the sun-spot army across the



solar disk. It was like watching a parade of masqueraders; each company of spots had its own characteristic and conspicuous make-up, and each kept its place in the line at a nearly invariable distance from the group in front of it and the one that followed.

The separate spots and groups did not, however, present an unvarying appearance. There was change as well as variety in this