"Very good; but if, on the other hand, there is a continual increase, how can the population continue the same?"
"Because the increase supposes a normal state; that is to say, the births are only estimated as compared with deaths from disease or old age. But then there are shipwrecks, inundations, plagues, and war, which sometimes exterminate entire communities at one fell swoop. Then whole nations die out and give place to the redundant populations of others; phenomena now observed in the cases of the aborigines of Australia and America."
"Very true."
"No signs of furs yet," cried Fritz, who was every now and then levelling his rifle at the phantoms on shore.
"We need not dread," continued Jack, "ever being hustled or jostled on the earth; life will fail us before space. There are now eight hundred millions of human beings in existence, and, according to the most moderate computation, room enough for twice that number. As it is, the most fertile sections of the earth are not the most populous; there are four hundred millions in Asia, sixty millions in Africa, forty in America, two hundred and thirty in Europe, and only seventy millions in the islands and continent of Oceanica!"
"To which," remarked Fritz, "you may add the eleven inhabitants of New Switzerland."
"Assuming, then, this calculation to be nearly accurate, though authorities vary materially in their computations of the earth's inhabitants, and regarding it in connexion with the average duration of human life, a thousand millions of mortals must perish in thirty-three years; to descend to detail, thirty millions every year, three thousand four hundred every hour, sixty every minute, or ONE EVERY SECOND."
"Aye," remarked Willis, "we are here to-day and gone to-morrow."
"Suppose, then, that the population of the earth were twice as great, cultivation would be extended, territories that are now lying waste would be teeming with life and covered with fertile fields, but the same beautiful equilibrium would be maintained."
"And the inhabitants of the planets," said Fritz, "what are they about?"