Omega - Camille Flammarion (free ebooks for android txt) 📗

atmosphere we breathe is composed of seventy-nine percent of nitrogen and twenty percent of oxygen, and that of the remaining one percent about one-half is aqueous vapor and three ten-thousandths is carbonic acid, the remainder being ozone, or electrified oxygen, ammonia, hydrogen and a few other gases, in exceedingly small quantities. Nitrogen and oxygen, then, form ninety-nine percent of the atmosphere, and the vapor of water one-half the remainder.

“But, gentlemen, from the point of view of vegetable and animal life, this half of one percent of aqueous vapor is of supreme importance, and so far as temperature and climate are concerned, I do not hesitate to assert that it is more essential than all the rest of the atmosphere.

“The heat waves, coming from the Sun to the Earth, which warm the soil and are thence returned and scattered through the atmosphere into space, in their passage through the air meet with the oxygen and nitrogen atoms and with the molecules of aqueous vapor. These molecules are so thinly scattered (for they occupy but the hundredth part of the space occupied by the others), that one might infer that the retention of any heat whatever is due rather to the nitrogen and oxygen than to the aqueous vapor. Indeed, if we consider the atoms alone, we find two hundred oxygen and nitrogen atoms for one of aqueous vapor. Well, this one atom has eighty times more energy, more effective power to retain radiant heat, than the two hundred others; consequently, a molecule of the vapor of water is 16,000 times more effective than a molecule of dry air, in absorbing and in radiating heat⁠—for these two properties are reciprocally proportional.

“To diminish by any great amount the number of these invisible molecules of the vapor of water, is to immediately render the Earth uninhabitable, notwithstanding its oxygen; even the equatorial and tropical regions will suddenly lose their heat and will be condemned to the cold of mountain summits covered with perpetual snow and frost: in place of luxurious plants, of flowers and fruits, of birds and nests, of the life which swarms in the sea and upon the land; instead of murmuring brooks and limpid rivers, of lakes and seas, we shall be surrounded only by ice in the midst of a vast desert⁠—and when I say we, gentlemen, you understand we shall not linger long as witnesses, for the very blood would freeze in our veins and arteries, and every human heart would soon cease to beat. Such would be the consequences of the suppression of this half hundredth part of aqueous vapor which, disseminated through the atmosphere, beneficently protects and preserves all terrestrial life as in a hothouse.

“The principles of thermodynamics prove that the temperature of space is 273° below zero. And this, gentlemen, is the more than glacial cold in which our planet will sleep when it shall have lost this airy garment in whose sheltering warmth it is today enwrapped. Such is the fate with which the gradual loss of the Earth’s water threatens the world, and this death by cold will be inevitably ours, if our earthly sojourn is long enough.

“This end is all the more certain, because not only the aqueous vapor is diminishing, but also the oxygen and nitrogen, in brief, the entire atmosphere. Little by little the oxygen becomes fixed in the various oxides which are constantly forming on the Earth’s surface; this is the case also with the nitrogen, which disappears in the soil and vegetation, never wholly regaining a gaseous state; and the atmosphere penetrates by its weight into the land and sea, descending into subterranean depths. Little by little, from century to century, it grows less. Once, as for example in the early primary period, it was of vast extent; the Earth was almost wholly covered by water, only the first granite upheaval broke the surface of the universal ocean, and the atmosphere was saturated with a quantity of aqueous vapor immeasurably greater than that it now holds. This is the explanation of the high temperature of those bygone days, when the tropical plants of our time, the tree ferns, such as the calamites, the equisetaceae, the sigillaria and the lepidodendrons flourished as luxuriously at the poles as at the equator. Today, both the atmosphere and aqueous vapor have considerably diminished in amount. In the future they are destined to disappear. Jupiter, which is still in its primary period, possesses an immense atmosphere full of vapors. The Moon does not appear to have any at all, so that the temperature is always below the freezing point, even in the sunlight, and the atmosphere of Mars is sensibly rarer than ours.

“As to the time which must elapse before this reign of cold caused by the diminution of the aqueous atmosphere which surrounds the globe, I also would adopt the period of 10,000,000 years, as estimated by the speaker who preceded me. Such, ladies, are the stages of world-life which nature seems to have marked out, at least for the planetary system to which we belong. I conclude, therefore, that the fate of the Earth will be the same as that of the Moon, and that when it loses the airy garment which now guarantees it against the loss of the heat received from the Sun, it will perish with cold.”

At this point the chancellor of the Columbian academy, who had come that very day from Bogota by an electric airship to participate in the discussion, requested permission to speak. It was known that he had founded on the very equator itself, at an enormous altitude, an observatory overlooking the entire planet, from which one might see both the celestial poles at the same time, and which he had named in honor of a French astronomer who had devoted his whole life to making known his favorite science and to establishing its great philosophical importance. He was received with marked sympathy and attention.

“Gentlemen,” he said, on reaching the desk, “in these two sessions