bable supposition that the corona is the atmosphere of the sun extending beyond its luminous disc, and that the red flames are substances floating in that atmosphere. In ordinary circumstances, the photosphere of the sun, or luminous envelope, is so overpowering, that the corona and the prominences are invisible. When, however, the eye is protected by the moon covering the luminous disc, they are at once revealed. No plausible theory has yet been given to explain the nature of the red flames. Some have attempted to trace a coincidence between the position of the flames and that of the dark spots of the sun; and it has been conjectured from this, that these dark spots are funnels in the luminous envelope, through which inflammable gases rise, and are burned in the region of the corona or atmosphere, where they appear as red flames. Others hold that the prominences are only the crests of the waves, or faculæ of the photosphere. The truth is, that we have almost no ground whatever, as yet, on which to base a theory. It was thought that during the last eclipse of 1851 several points would be set at rest; but the evidence was very conflicting, arising very much from the flurried state of feeling caused by the startling character of the phenomena, and their very brief duration. European astronomers are looking forward to the eclipse of the present year (1860) with eagerness, as it is confidently expected that it will be conclusively settled whether the corona and red prominences really belong to the sun or the moon; and, for this purpose,
