The San Francisco call., 1909-10-03

ton being somewhat less than half the amount re-
ceived by the earth The day on Mars is about halt
hour longer than here and the seasons nearly
= twice as long Summer in the northern hemisphere
lasts 3Sl days and winter only 800 At the north pole
the night is 800 days long; that is the sun never
rises during that period and Martians living within
"a degrees OF the north pole are consequently IN
darkness for a time corresp sponding to more than
10 months. In the southern hemisphere the winter
is longer than the summer, the night at the south
pole being 3S1 days and the day 500 days long, dur
ing which time the sets. We have similar
effect in the land OF the midnight where the
remains above the horizon for three months but
imagine living in region where daylight lasts for 10
monthst We can we'll imagine the Martians forsak-
ing the dreary realms of darkness for the land where
the sun SETS retreating from to the other
according to the varying seasons.
The surface of Mars is little less than One-third
that the EARTH trife than the total OF
dry land on planet The volume OF the planet IS
one-seventh and its only one-tenth that OF the
earth This determined with great accuracy from
observations of the two little moons, Phobos and
Dilmos, discovered by Professor Asaph Hall OF the
Naval observatory, Washington, in 1877.
The inner moon, Phobos, with diameter Of seven
miles, makes one revolution around the planet in
period of hours and half three times during
ing the of Martian day. In fact, 1t moves
much faster than Mars that inhabitant Of the
planet the moon would seem rise in the west and
crescent and full in single night
The outermost moon, Dilmos, with diameter OF
five six miles, completes its journey period
OF so hours and Is minutes Consequently there
must always be moon adorning the sMartian sky.
But how small in size these moons as compared
with own glorious satellite. with its diameter Of
1000 miles.
FORCE OF GRAVITY ON MARS
The weight of body at the surface of planet de-
pends upon the attraction of gravitaton, and this in
with the and decreases with the square
OF the diameter of the planet AS Mars contains only
one-tenth much matter the earth its attraction
equal distances will be only one-tenth great but
the other hand the surface Of Mars is only one
half far from the center IS the earths surface.
and on this the attraction will be quadruped
Thus the surface gravity of Mars will be about four
tenths that of the earth.
Owing to the lessened force of gravity the Mar
tans might attain strength and greater than
ours without being burdensd by their weight
Dealing, as they would have with rocks only
little more than third as heavy as they would be
here, their work would be greatly more effective.
Nevertheless, according to a calculation made by
J. Orr of the British Astronomical association it
would require army Of 20OO000O0 men, working
for thousand years to construct the canal system
outlined Mars
THE CANALS AS AN ENGINEERING FEAT
The canals as drawn by Lowell and his assistants
present the appearance of lines laid down by rule
and compass Each line varies in width from
miles in the case of the narrowest to Is or 20
miles, each line stretching across the planets sur
face an undeviated, unbroken course. The length
of these lines is enormous, many stretching
three thousand miles across the surface of this
strange planet. More remarkable than their length
the direcness of these lines-they always take the
shortest the great circle course, between the two
points they join Allowing for the larger size of the
earth" to quote illustration given by Professor
Poor in his book on "The Solar System" such line
the distinct ones would stretch from London
to Calcutta, crossing mountains, plains and
unbroken straight band 40 miles wide"
No part of the Martian surface is entirely free
from this network of lines, which furrow so called
land and dark seas alike. Those who see in these
markings vast irrigating system also contend that
the water flows from the north during the northern
summer
Starting at the polar cap, it sweeps through the
network of canals through the temperate regions to
again quote Professor Poor. past the equator and
fertiizes the plains some 35 degrees south lat-
tude Thus that great part of the surface lying
between IS degrees south and 35 degrees north lat
tude Grom Buenos Aires in the south to Washing
in the north) the water in the called canals
flows, in opposite directions in winter and in sum
mer; flows up hill readily as down hill To over
the obvious physical impossibilities of sucn
system Lowell is forced to the conclusion: No
natural force propels it (water) and the inference
is fortnight and inevitable that it is arthcially
helped to its end. The engineering feat here pro-
claimed staggers the imagination
TO push speculation and imagination to this ess-
treme is farcical when the simplest and most ele
mentary of the planetary conditions are still un-
known There is no direct evidence that water even
exists upon the surface OF Mars; its presence is in
ferred from the behavior of the polar caps Whether
this inference is correct or not is open question
The imaginative theory suggested by the writer
earlier in this article concerning the dark outlines on
Mars as resembling huge aeroplanes with the addi-
tiona suggestion that the network of lines may be