To an amateur possessed of a small telescope, the Sun offers (when the weather is above the English average of recent years) a very great and constant variety of matters for studious scrutiny in its so-called “spots.” To the naked eye, or even on a hasty telescopic glance, the Sun presents the appearance of a uniform disc of yellowish white colour, though often a little attention will soon result in the discovery of a few, or it may be many, little black, or blackish patches, scattered here and there over the disc seemingly without order or method. We shall presently find out, however, that this last-named suggestion is wholly inaccurate. Though commonly called “spots,” these dark appearances are not simple spots, as the word might imply, for around the rather black patch which constitutes generally the main feature of the spot there is almost invariably a fringe of paler tint; whilst within the confines of the black patch which first catches the eye there is often a nucleus or inner portion of far more intense depth of shade. The innermost and darkest portion being termed the _nucleus_, the ordinary black portion is known as _umbra_, whilst the encompassing fringe is the _penumbra_. It is not always the case that each individual umbra has a penumbra all to itself, for several spots are occasionally included in one common penumbra. And it may further be remarked that cases of an umbra without a penumbra and the contrary are on record, though these may be termed exceptional, often having relation to material organic changes either just commencing or just coming to a conclusion. A marked contrast subsists in all cases between the luminosity of the penumbra and that of the general surface of the Sun contiguous. Towards its exterior edge the penumbra is usually darker than at its inner edge, where it comes in contact with the umbra. The outline of the penumbra is usually very irregular, but the umbra, especially in the larger spots, is often of regular form (comparatively speaking of course) and the nucleus (or nuclei) of the umbra still more noticeably partakes of a compactness of outline. Spots are for the most part confined to a zone extending 35° or so on each side of the solar equator; and they are neither permanent in their form nor stationary in their position. In their want of permanence, they are subject, apparently, to no definite laws, for they frequently appear and disappear with great suddenness.