urface peculiarity on the Earth or
moon at all resembles these features. The moon's surface as you
know is cracked and

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streaked. But the cracks are what we generally find cracks to
be--either aimless, wandering lines, or, if radiating from a
centre, then lines which contract in width as they leave the
point of rupture. Where will we find cracks accurately parallel
to one another sweeping round a planet's face with steady
curvature for, 4,000 miles, and crossing each other as if quite
unhampered by one another's presence? If the phenomenon on Mars
be due to cracks they imply a uniformity in thickness and
strength of crust, a homogeneity, quite beyond all anticipation.
We will afterwards see that the course of the lines is itself
further opposed to the theory that haphazard cracking of the
crust of the planet is responsible for the lines. It was also
suggested that the surface of the planet was covered with ice and
that these were cracks in the ice. This theory has even greater
difficulties than the last to contend with. Rivers have been
suggested. A glance at our own maps at once disposes of this
hypothesis. Rivers wander just as cracks do and parallel rivers
like parallel cracks are unknown.

In time the many suggestions were put aside. One only remained.
That the lines are actually the work of intelligence; actually
are canals, artificially made, constructed for irrigation
purposes on a scale of which we can hardly form any conception
based on our own earthly engineering structures.

During the opposition of 1894, Percival Lowell, along with A. E.
Douglass, and W. H. Pickering,

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observed the planet from the summit of a mountain in Arizona,
using an 18-inch refracting telescope and every resource of
delicate measurement and spectroscopy. So superb a climate
favoured them that for ten months the planet was kept under
continual observation. Over 900 drawings were made and not only
were Schiaparelli's channels confirmed, but they added 116 to his
79, on that portion of the planet visible at that opposition.
They made the further important discovery that the lines do not
stop short at the dark regions of the planet's surface, as
hitherto believed, but go right on in many cases; the curvature
of the lines being unaltered.

Lowell is an uncompromising advocate of the "canal" theory. If
his arguments are correct we have at once an answer to our
question, "Are there other minds than ours?"

We must con