dea that the greenish parts are seas
had to be quite given up, though it appeared so attractive. The idea now
generally believed is that the greenish parts are vegetation--trees and
bushes and so on, and that the red parts are deserts of reddish sand,
which require irrigation--that is to say, watering--before anything can
be grown on them. The apparent doubling of the canals may be due to the
green vegetation springing up along the banks. This might form two broad
lines, while the canal itself would not be seen, and when the vegetation
dies down, we should see only the trench of the canal, which would
possibly appear faint and single. Therefore the arrangements on Mars
appear to be a rich and a barren season on each hemisphere, the growth
being caused by the melting of the polar ice-cap, which sends floods
down even beyond the Equator. If we could imagine the same thing on
earth we should have to think of pieces of land lying drear and dry and
dead in winter between straight canal-like ditches of vast size. A
little water might remain in these ditches possibly, but not enough to
water the surrounding land. Then, as summer progressed, we should hear,
'The floods are coming,' and each deep, huge canal would be filled up
with a tide of water, penetrating further and further. The water drawn
up into the air would fall in dew or rain. Vegetation would spring up,
especially near the canal banks, and instead of dreary wastes rich
growths would cover the land, gradually dying down again in the winter.
So far Mars seems in some important respects very different from the
earth. He is also less favourably placed than we are, for being so much
further from the sun, he receives very much less heat and light. His
years are 687 of our days, or one year and ten and a half months, and
his atmosphere is not so dense as ours. With this greater distance from
the sun and less air we might suppose the temperature would be very cold
indeed, and that the surface would be frost-bound, not only at the
poles, but far down towards the Equator. Instead of this being so, as we
have seen, the polar caps melt more than those on the earth. We can
only surmise there must be some compensation we do not know of that
softens down the rigour of the seasons, and makes them milder than we
should suppose possible.

Of course, the one absorbing question is, Are there people on Mars? To
this it is at present impossible to reply. We can only say the planet
seems