professed to explain the charred aspect of the moon-- a disaster
which they attributed to the intensity of the solar heat; only,
on being reminded that comets have an atmosphere, and that the
moon has little or none, they were fairly at a loss for a reply.

Others again, belonging to the doubting class, expressed certain
fears as to the position of the moon. They had heard it said
that, according to observations made in the time of the Caliphs,
her revolution had become accelerated in a certain degree.
Hence they concluded, logically enough, that an acceleration of
motion ought to be accompanied by a corresponding diminution in
the distance separating the two bodies; and that, supposing the
double effect to be continued to infinity, the moon would end by
one day falling into the earth. However, they became reassured
as to the fate of future generations on being apprised that,
according to the calculations of Laplace, this acceleration of
motion is confined within very restricted limits, and that a
proportional diminution of speed will be certain to succeed it.
So, then, the stability of the solar system would not be deranged
in ages to come.

There remains but the third class, the superstitious.
These worthies were not content merely to rest in ignorance;
they must know all about things which had no existence whatever,
and as to the moon, they had long known all about her. One set
regarded her disc as a polished mirror, by means of which people
could see each other from different points of the earth and
interchange their thoughts. Another set pretended that out of
one thousand new moons that had been observed, nine hundred and
fifty had been attended with remarkable disturbances, such as