644 The [Harmony of Creation. 
Minor currents and eddies are produced by grass, stones, 
the leaves of the forest, the surface of waters, owing to 
their unequal power of absorbing and radiating heat. The 
air continually moves in obedience to these laws, and thus 
sweeps along, in constantly renewed currents, over the sur- 
face of the bodies which cause these constant perturbations. 
The carbonic acid which we exhale is carried away im- 
mediately it is breathed out, by these motions of the ‘air; 
not a single atom that has escaped our lungs will again 
return to their cells. 
The attraction of the sun and moon cause immense 
tides in the aérial ocean, just as they draw the tides of sea 
and river. The atmosphere thus equally distributes heat, 
and has a power also of retaining this indispensible neces- 
sity of life. It also distributes light, and enables us to see 
terrestrial objects at a great distance, such as a ship rising 
upon the horizon, and to penetrate through the crystal 
depths of the heavens, which, without the medium of the 
air, would wear a black funereal aspect. It is the bearer 
of sounds, without which the view of a beautiful landscape 
would seem dreary and desolate, if it lay before us in un- 
interrupted silence. It enables us, above all, to commu- 
nicate the sound of language, and all animated nature to 
express its feelings. 
The same power which maintains the celestial bodies in 
their orbits, and compels the planets to wander in fixed 
ellipses through endless space, also keeps with immutable 
constancy the regular alternation of ebb and flood. The 
influence of the tides upon the marine plants and animals 
is of essential importance. Many of the commonest alge 
best flourish when bathed alternately with floods of water 
and air. Many plants and animals could not possibly live 
without a continual oscillation of the tides. Thus the re- 
pose of the seas is constantly disturbed by tropical heat 
and polar frost, but the ocean has the same tendency to 
restore the equilibrium of its temperature as the atmo- 
sphere has, and thus numerous warm and cold currents are 
produced, by which the waters of the different zones are 
being continually exchanged. 
The influence of the oceanic currents is immense. They 
moderate the heat of the tropical zone, and warm the higher 
latitudes. The influence of the Gulf stream may be traced as | 
far as the west coasts of Spitzbergen and Novaja, Sewlja, 
Scotland, and Norway, where forests clothe the mountain 
sides up to a height of several thousand feet, which would ~ 
