“The endemic and epidemic diseases in Scotland,” says Malthus, “fall chiefly, as is usual, on the poor.... To the same causes, in a great measure, are attributed the rheumatisms which are general and the consumptions which are frequent among the common people. Wherever, in any place, from particular circumstances, the condition of the poor has been rendered worse, these disorders, particularly the latter, have been observed to prevail with greater force.” In these observations Mr. Malthus lays the very foundation of the science of health. Health in Europe, he shows, is incompatible with high birth-rates, which cause over-crowding, consumption, and death. Scotland, says Malthus, writing in 1806, is certainly still over-peopled, but not so much as it was a century ago, when it contained fewer inhabitants. Scotland in 1801, had 1,608,420 inhabitants, and in 1871, 3,360,018, so that its time of doubling has been nearly seventy years, or much slower than that of England and Wales. With regard to Ireland, there is only one short paragraph in Malthus’ tenth Chapter of Book Second upon that country. We give it in its entirety:—“The details of the population of Ireland are but little known. I shall only observe, therefore, that the extended use of potatoes has allowed of a very rapid increase of it during the last century (18th). But the cheapness of this nourishing root, and the small piece of ground which, under this cultivation, will in average years produce the food for a family, joined to the ignorance and barbarism of the people, which have prompted them to follow their inclinations with no other prospect than an immediate bare subsistence, have encouraged marriage to such a degree that the population is pushed much beyond the industry and present resources of the country; and the consequence naturally is that the lower classes of people are in the most depressed and miserable state. The checks to the population are, of course, chiefly of the positive kind, and arise from the diseases occasioned by squalid poverty, by damp and wretched cabins, by bad and insufficient clothing, by the filth of their persons, and occasional want.” Malthus here foresaw the famine of 1848, which, aided by emigration, reduced the Irish population from 8,175,124 in 1841 to 6,552,385 in 1851. Doubtless, as shown by Mr. J. S. Mill, Professor Laveleye, and other subsequent writers, the miserable condition of the Irish peasant is due mainly to the intolerable feudal laws of land tenure, which have been so violently put an end to in our happiest of modern European States, France. CHAPTER VII. DETACHED ESSAYS.