1865.] Astronomy. 655 



measurements) the latter must be about thirty times smaller than the 

 former ; on some occasions the outlines of some of the elevations 

 were so clearly and sharply defined, that they could be compared to 

 the appearance of a coarse shingle beach. During an examination of 

 the sun through a red haze, which was found extremely favourable to 

 definition, a number of the rice-grain forms were noticed lying in 

 various directions one with another; the length of some of them 

 being estimated at 8" or 10" and about 2' in width. These waves, or 

 ridges of photospheric cloud, were not of equal elevation throughout 

 their entire length, but seemed to have an irregular outline of eleva- 

 tion, such as a cumulous cloud generally presents, so that the top of 

 the very wave, or ridge, that causes the mottled appearance on the sun 

 was itself most irregular in the outline of its upper surface. The 

 sides of these waves, or ridges were of very great inclination, not 

 very greatly removed from the perpendicular ; the indentations, or 

 valleys, between them intersecting each other most irregularly. In 

 some parts of the photosphere, where the rounder forms prevailed, 

 the indentations seemed very deep, and penetrated the cloudy stratum 

 in such a slanting position, that the bottom of them could not be seen. 



These indentations seemed to be at least 2" in depth, or 1,000 

 miles, but the estimation of their profundity is a difficult matter. 

 The tops of the ridges were the brightest, while the valleys, or inden- 

 tations, appeared somewhat shaded and less luminous. On some 

 occasions these were noticed, speckled with black dots, or pores. 

 The whole of this mottled surface seems to be disposed in the form 

 of huge undulations, very similar to ranges of mountains, as shown on 

 a good map ; the elevated portions appearing as minute faculce, but far 

 smaller, and far more difficult to observe, than the ordinary faculee of 

 the Sun. 



Mr. Brodie has given an interesting account of the progress of an 

 unusually wide bridge of luminous matter, which formed completely 

 across a large oval-shaped spot, in the course of a few hours, showing 

 the extreme mobility of the sun's photosphere. The luminous matter 

 which formed the bridge, must have moved at the enormous velocity 

 of 14,000 miles per hour. Mr. Brodie concludes, that from what he 

 has observed of the Sun's surface, he cannot conceive the possibility 

 of any regular form of particles so interlacing themselves together as 

 to form the wonderful nodosity of the photosphere of the Sun, since 

 any such interlacing would apparently necessitate a comparative even- 

 ness and uniformity of surface, and so far as he has been able hitherto 

 to see the peculiar formation of the Sun's envelope, he has been as 

 unable to reconcile the willow-leaf theory with it. 



Mr. Lockyer's observations are devoted to one spot, which appears 

 to have been remarkable in several respects ; at one part a bright 

 tongue of facula stretched out into the umbra, in the centre were what 

 appeared to be clouds, which after a time appeared to condense into 

 willow leaves ; at another side was a promontory, in which the 

 willow leaves were changing the direction of their larger axes, with 

 respect to the centre of the spot, whilst in another part, the penumbra 

 seemed composed of layers, and the willow leaves were arranged like 



