Evening star. [volume] (Washington, D.C.) 1854-1972, 1878-06-08
PEOPLE ON MIRS'S MOONS,

prof. r. A. Proctor, in Belgravia.l
Probably the most convenient assumption
We can make is that there may be creatures in
a general respect like ourselves on those moons
of Mars, but that, owing to the extreme rarity
of the atmosphere, their vital energy is SO far
reduced that they are not more active than we
are d. spite the feeble action of gravity in their
world. The air must be exceedingly rare, most
certainly, even if the quantity Is proportional
to the volumes OF these moons. On this as
sumption the quantity OF air is less than the
quantity Of terrestrial as / is less than 400
fines 400 times iU0-that is, it amounts only 10
j 6i,COt,tW part OF the terrestrial air
Being spread over a surface which is but
1l6O,00O of the eaTth'S il follows that the guam
tity of air above each square mile of surface is
l-4OO part only OF the quantity over each square
mile Of our eaTtnS surface. This would be
little enough in all conscience, but this is no
all. For the action OF gravity being, according
Ia our assumption, only Loco of terrestrial
gravity, il follows that the atmospheric pres
sure, and therefore density, is further reduced
III this degree. giving finally density of equal
only TO 10000 of the density of our own air.
Now, at Il hight OF seven miles where the
atmospheric pressure is reduced to One-fourth
that 4. the sta level, men of ordinary cons itu-
tons would perish in 4 few moments. if nOt in
SANITY. In CoXwelrS ascent to nearly that
hight, GlaisheT tainted, and CCXwell only Just
had strength LETT 10 draw the yIive-String with
bis teeth (hiS hands being already pOwereSS)
Yet at the hight OF seven miles the density of
the air Is tU.U times greater than that which,
according To our very reasonable assumption,
prevails at the surface of The Marian moons
We can very we'll believe, then, that in
whatever way the inhabitants of these moons
may be adapted, cOrpOTedlly and constitution
ally, for existence in their small homes, the
rarity of the air there must tend to reduce
their vital energy. SO that we may well ina
CINE that, instead OF being able To leap to a
hight of half a mile or over distance of two
OF three miles, they are not more active than
We are on earth with six hundred times gr sat-
er weight, but far more effective reSpira ion
We might, perhaps, 90 even further than this,
and assume that, in order to give the inhabi-
tantS Of these moons locomotive powers pro-
pOrtiOned in the same way TO their own dimen-
siODS as ours are, they must be supposed very
much smaller than We are.
We might imagine then in an atmosphere so
exceedingly attenuated that creatures which
could have vitality enough to move freely
about must be no larger than flies or ants and
must have also some such provision as insects
have for more effective inspiration. In this
way We might find in the Marian moons a
miniature of our own earth, not only in the
Proportions Of these worlds themselves, but
also in those Of the creatures living upon them
But il would not be very interesting To con
slider mere miniatures of our earth, such as
the moons of Mars would thus come TO be re-
gaTded. Indeed, in that case, little more could
be said than that all the relations presented by
this earth were or might be represented in he
NaTtian moons, but on greatly reduced