Note 25 — Chapter V · NITROGEN AND AIR
George Kamensky translation
In Chapter III., Note 4, an approximate calculation is made for the determination of the balance of oxygen in the entire atmosphere; it may therefore he supposed that the composition of air will vary from time to time, the relation between vegetation and the oxygen absorbing processes changes; but as the atmosphere of the earth can hardly have a definite limit and we have already seen (Chapter IV., Note 33) that there are observations confirming this, it follows that our atmosphere should vary in its component parts with the entire heavenly space, and therefore it must he supposed that any variation in the composition by weight of the air can only take place exceedingly slowly, and in a manner imperceptible by experiment.