the surface of Mars one of extreme complexity, a multitude of bright
spots in places, but with a general fixity of character which led him to
believe that the appearances were not atmospheric. He indeed attributed
to Mars an attenuated atmosphere and thought that some of the vagaries
in its surface characters were due to variations in our own atmosphere
He did not find the Schiaparelli canals as distinct in outline as given
by that ingenious observer. He noted many brilliant spots on Mars and
indicated the disturbing influences of vibrations produced by winds on
the surface of our earth in connection with changes in the earth's
atmospheric envelope.

In 1888 M. Perrotin continued his observations on the channels of Mars
and noted changes. The triangular continent (Lydia of Schiaparelli) had
disappeared, its reddish white tint indicating, or supposed to indicate,
land, was then replaced by the black or blue color of the seas of Mars.
New channels were observed, some of them in "direct continuation" with
channels previously observed, amongst these an apparent channel through
the polar ice cap. Some of these seemed double, running from near the
equator to the neighborhood of the North Pole. The place called Lydia
disappeared and reappeared. A strange puzzling statement was made that
the canals could be traced straight across seas and continents in the
line of the meridian. M. Terby confirmed many of these observations.
Later the so-called "inundation of Lydia," observed by M. Perrotin, was
doubted. Schiaparelli himself, Terby, Niesten at Brussels, and Holden at
the Lick Observatory, failed to remark this change. These observers did
not double the canals satisfactorily, but all agreed upon the striking
whiteness and brightness of the planet.

M. Fizeau (1888) argued that the Schiaparelli canals were really glacial
phenomena, being ridges, crevasses, rectilinear fissures, etc., of