THE GEOLOGIST. 
JANUARY, 1861. 
HIGH AND LOW LIFE. 
By George E. Roberts. 
Our knowledge of tlie limits of animal life have been notably 
extended during the year which has just departed. Air, blown upon 
an adhesive surface by the aeroscope on the summit of Etna, twelve 
thousand feet above the sea level, has been found to contain large 
quantities of Diatomace^e ; and thus the presence of a zone of life 
has been discovered to us, soaring not only above the limits hitherto 
fixed, but above the range of physical phenomena in the mountain 
itself. 
And now the ocean-depths have given up a secret as marvellous. 
We are taught that at a depth below the surface nearly as great as 
the height of the infusorial zone above it, animals as high in the 
scale of being as starfishes are enjoying life. The one discovery is a 
fitting pendant to the other, and yet, how great is their difference ! 
In the one case the extreme rarification of the atmosphere seemed to 
our notions to render life impossible ; in the other, the enormous 
pressure of the opposite element, which in the homes of these star- 
fishes must amount to at least a ton and a-half on the square inch, is 
so greatly at variance with our belief, that we are confounded at the 
very outset of the inquiry. The capability in an animal so well 
accustomed to air as the starfish — whose ordinary domain is the sea- 
beach — to exist without it, and its inherent power of withstanding a 
VOL. IV. A 
