The earthly corona was unequal in width, and to the westward was very distinctly brightened, while on the other side it was narrow and comparatively faint.

While watching this phenomenon through the lower lens, I thought that I could perceive behind or through the widest portion of the halo a white light, which at first I mistook for one of those scintillations that had of late become scarcely discernible.

But after a time it extended visibly beyond the boundary of the halo itself, and I perceived that the edge of the Sun's disc had come at last into view.

It was but a minute and narrow crescent, but was well worth watching.

The brightening and broadening of the halo at this point I perceived to be due, not to the Sun's effect upon the atmosphere that produced it, but chiefly to the twilight now brightening on that limb of the Earth's disc; or rather to the fact that a small portion of that part of the Earth's surface, where, if the Sun were not visible, he was but a very little below the horizon, had been turned towards me.