stretched, vegetable life would still suffice without effort to clothe the increased surface. But since the size of the globe inexorably limits the amount of vegetable produce possible of growth, the limited vegetable produce must, in its turn, limit the amount of animal life which can be sustained. While increased knowledge, skill and care may augment the means of subsistence obtainable from the earth, yet animal life multiplies more rapidly than can its food. As is truly said by the author just quoted: "From a consideration of the law of agricultural industry, and an estimate of the rate at which the means of subsistence could be increased in old countries, even under the most favourable circumstances, it may be inferred with certainty that these means of subsistence could not possibly be increased so fast as to permit population to increase at its natural rate … Let us apply the American rate of increase to the population of this country. Is it conceivably possible that the population of England or any old country should double itself every twenty-five years? In Great Britain there are now" (the book was written many years ago) "about twenty-one millions; is it conceivable that the means of subsistence could be so rapidly increased as to allow these twenty-one millions to swell to forty-two millions in the first twenty-five years; to eighty-four millions in the next; 168 millions in the next, &c.? The supposition is evidently absurd. Even the rate of increase of the last fifty-three years (in which time the population has doubled) cannot possibly be long continued. If it were, it would increase our population in three centuries to about 1300 millions; or, in other words, to more than the total population of the globe, which is estimated at about 1000 millions."
Wherever, then, we look throughout Nature, we find proofs of the truth of the law, that "there is a tendency in all animated existence to increase faster than the means of subsistence." This is the law of which Miss Martineau said that it could be no more upset than a law of arithmetic; this is the law which John Stuart Mill regarded "as axiomatic;" this is the law which the Lord Chief Justice designated "an irrefragable truth." Controversialists may quarrel as to its consequences, and may differ as to man's duty in regard to them, but no controversy can arise on the law itself, any more than on the sphericity of the earth.
