METEOES AND COMETS. 
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water of varjdng depth, in muscle, bone, or brain, and 
live through all temperatures from zero to 135° ; life 
that breathes by lungs, by gills, by spiracles, or by 
none of these. There may be conscious intelligent 
beings who can live on entirely different food from 
that we need, or on no food at all; they may never 
need sleep, and have neither head nor feet. Infinite 
wisdom can plan where we can not imagine. 
But suppose that the planets are not inhabited, 
could we say they are useless orbs ? Suppose the 
other suns in the universe should have no attending 
planets, are they therefore created in vain ? Are they 
not ornaments hung in the sky which call forth our 
admiration night after night ? They are queries in 
the firmament to stir our thoughts and widen our 
mental horizon. 
METEORS AND COMETS. 
INo one can be out under an open sky on a clear 
night without seeing bright objects shooting across 
the heavens in one direction or another. They look 
like red-hot halls moving through the air and leaving 
in their rear a trail of illuminated dust particles. 
What are they, and whence do they come ? Many 
have reached the earth, and their composition has 
been determined. They often look like a black lump 
of iron. Upon being broken in two, the smaller ones 
generally show a lamellated structure, as if they had 
grown by adding layers of matter. They are com¬ 
posed of many of the minerals found in the earth, 
chiefiy iron. 
