t the case, for with the last appearance of the
bright reflected sunlight there appeared a dim circle of light around
the Moon's disc, and the whole surface became faintly visible, and
continued so until the end of totality."

A total eclipse of the Moon which happened on January 28, 1888, was
observed in many places under exceptionally favourable circumstances as
regards weather. The familiar copper colour is spoken of by many
observers. The Rev. S. J. Perry makes mention[120] of patches of colour
even as bright as "brick red, almost orange in the brighter parts," and
this, 20 minutes before the total phase began. Mr. Perry conducted on
this occasion spectroscopic observations for the first time on an
eclipsed Moon, but no special results were obtained.

Various explanations have been offered for these diversities of
appearance. Undoubtedly they depend upon differences in the condition of
the Earth's atmosphere, such as the unusual presence or unusual absence
of aqueous vapour; but it cannot be said that the laws which control
these diversities are by any means capable of being plainly enunciated,
notwithstanding that the explanation generally in vogue dates from as
far back as the time of Kepler. He suggested that the coppery hue was a
result of the refraction of the Earth's atmosphere which had the effect
of bending the solar rays passing through it, so that they impinged upon
the Moon even when the Earth was actually interposed between the Sun and
the Moon. That the outstanding rays which became visible are red may be
considered due to the fact that the blue rays are absorbed in passing
through the terrestrial atmosphere, just as both the eastern and western
skies are frequently seen to assume a ruddy hue when illuminated in the
morning or evening by the solar rays at or near sunrise or sunset.

Owing to the variable meteorological condition of our atmosphere, the
actual quantity of light transmitted through it is liable to
considerable fluctuations, and no wonder therefore that variations occur
in the appearances presented by the Moon during her immersion in the
Earth's shadow.

It has been suggested that if the portion of the Earth's atmosphere
through which the Sun's rays have to pass is tolerably free from aqueous
vapour, the red rays will be almost wholly absorbed, but not the blue
rays; and the resulting illumination will either only render the Moon's
surface visible with a greyish blue tinge, or not visibl