484 PHILOSOPHICAL TRANSACTIONS. [aNNO l/QS. 



small points of an unequal light; but they are evidently an unevenness or rough- 

 ness of high and low parts. 



Sept. 11,1 79'2, the faculse, in the preceding part of the sun, were much 

 gone out of the disc, and those in the following come on. A dark, spot also was 

 come on with them. Sept. 13, 1792, there were a great number of faculas on 

 the equatorial part of the sun, towards the preceding and following parts. There 

 were none towards the poles; but a roughness was visible every where. Sept. l6, 

 1702, the sun contained many large faculae, on the following side of its equator, 

 and also several on the preceding side. But none about the poles. They seemed 

 generally to accompany the spots, and probably, as the faculae certainly were 

 elevations, a great number of them may occasion neighbouring depressions, that 

 is, dark spots. 



The faculae being elevations, very satisfactorily explains the reason why they 

 disappear towards the middle of the smi, and re-appear on the other margin; 

 for, about the place where we lose them, they begin to be edge-ways to our view; 

 and if between the faculae should lie dark spots, they will most frequently break 

 out in the middle of the sun, because they are no longer covered by the side 

 views of these faculae. 



Sept. 22, 1792, there were not many faculae in the sun, and but few spots; 

 the whole disc however was very much marked with roughness, like an orange. 

 Some of the lowest parts of the inequalities were blackish. Sept. 23, 1792, 

 The following side of the sun contained many faculae, near the limb. They took, 

 up an arch of about 30°. There were likewise some on the preceding side. The 

 north and south rough as usual; but differently disposed. The faculae were 

 ridges of elevations above the rough surface. Feb. 23, 1794, by an experiment 

 just then tried, I found it confirmed that the sun cannot be so distinctly viewed 

 with a small aperture and faint darkening glasses, as with a large aperture and 

 stronger ones ; this latter is the method I always use. One of the black spots on 

 the preceding margin, which was greatly below the surflice of the sun, had next 

 to it a protuberant lump of shining matter, a little brighter than the rest of the 

 sun. About all the spots the shining matter seemed to have been disturbed; and 

 was uneven, lumpy, and zig-zagged in an irregular manner. I call the spots 

 black, not that they are entirely so, but merely to distinguish them; for tliere 

 was not one of them which was not partly, or entirely, covered over with whitish 

 and unequally bright nebulosity, or cloudiness. This, in many of them, comes 

 near to an extinction of the -spot; and in others seems to bring on a sub- 

 division. 



Sept. 28, 1794, There was a dark spot in the sun on the following side. It 

 was certainly depressed below the shining atmosphere, and had shelving sides of 

 shining matter, which rose up higher than the general surface, and were brightest 



