as to the educated world at large, to investigate the
evidence for so portentous a conclusion. To do this requires only a
general acquaintance with modern science, more especially with mechanics
and physics, while the main contention (with which I shall chiefly deal)
that the features termed 'canals' are really works of art and
necessitate the presence of intelligent organic beings, requires only
care and judgment in drawing conclusions from admitted facts. As I have
already paid some attention to this problem and have expressed the
opinion that Mars is not habitable,[2] judging from the evidence then
available, and as few men of science have the leisure required for a
careful examination of so speculative a subject, I propose here to point
out what the facts, as stated by Mr. Lowell himself, do _not_ render
even probable much less prove. Incidentally, I may be able to adduce
evidence of a more or less weighty character, which seems to negative
the possibility of any high form of animal life on Mars, and, _a
fortiori_, the development of such life as might culminate in a being
equal or superior to ourselves. As most popular works on Astronomy for
the last ten years at least, as well as many scientific periodicals and
popular magazines, have reproduced some of the maps of Mars by
Schiaparelli, Lowell, and others, the general appearance of its surface
will be familiar to most readers, who will thus be fully able to
appreciate Mr. Lowell's account of his own further discoveries which I
may have to quote. One of the _best_ of these maps I am able to give as
a frontispiece to this volume, and to this I shall mainly refer.

[Footnote 2: _Man's Place in the Universe_ p. 267 (1903).]

_The Canals as described by Mr. Lowell._

In the clear atmosphere of Arizona, Mr. Lowell has been able on various
favourable occasions to detect a network of straight lines, meeting or
crossing each other at various angles, and often extending to a thousand
or even over two thousand miles in length. They are seen to cross both
the light and the dark regions of the planet's surface, often extending
up to or starting from the polar snow-caps. Most of these lines are so
fine as only to be visible on special occasions of atmospheric clearness
and steadiness, which hardly ever occur at lowland stations, even with
the best instruments, and almost all are seen to be as perfectly
straight as if drawn with a ruler.

_The Double Canals._

Under except