advantages for using it, that called these multitudes of human beings into existence, to eat the food which they paid for by their labour. And it should be equally obvious that the existence of forty-six millions of people upon 121,000 square miles of territory depends entirely upon our finding a market for our manufactures abroad, for so only are we able to pay for the food of the people. It is most unfortunate that these exports must, with our present population, include coal, which, if we had any thought for posterity, we should guard jealously and use sparingly; for in five hundred years at the outside our stock will be gone, and we shall sink to a third-rate Power at once. We are sacrificing the future in order to provide for an excessive and discontented population in the present. During the present century we have begun to be conscious that our foreign trade is threatened; and so sensitive is the birth-rate to economic conditions that it has begun to curve very slightly downward in relation to the death-rate, instead of descending with it in parallel lines.[23] This may be partly due to the curtailment of facilities for emigration, owing to the filling up of the new countries. For emigration does not diminish the population of the country which the emigrants leave; it only increases its birth-rate. We are now in a position to enumerate the causes which actually lead to an increase in the population of a country. The first is an increase in the amount of food produced in the country itself. If the parks and gardens of the gentry were ploughed up or turned into allotments, a few hundred thousands would be added to the population of the United Kingdom, at the cost of one of the few remaining beauties which make our country attractive to the eye. The introduction of the potato into Ireland added several millions of squalid inhabitants to that ill-conditioned island, and when the crop failed, large numbers of them inflicted themselves on the United States, to the detriment of that country. The richest countries to-day are those which produce more food than they require, such as the United States, Canada, Australia, Roumania, and the Argentine. (We need hardly say that throughout this survey we are using the statistics of the years immediately before the war.) But this state of things cannot last long, for the net increase in such countries is invariably high, either by reason of a very high birth-rate, as in Roumania, or because newcomers flock in to enjoy a land of plenty. Another condition which leads to abnormally rapid increase is found when a civilised nation conquers and administers a backward country, introducing better methods of agriculture, and especially irrigation and the reclamation of waste lands. The alien Government also gives greater security, without raising the standard of living among the natives, since the dominant race usually monopolises the lucrative careers. In this way we are directly responsible for