Potatoes the National Food of the Irish
There is one instance, and only one, of a great European people possessing a very cheap national food. In Ireland the labouring classes have for more than two hundred years been principally fed by potatoes, which were introduced into their country late in the sixteenth or early in the seventeenth century. Now, the peculiarity of the potato is, that until the appearance of the late disease, it was, and perhaps still is, cheaper than any other food equally wholesome. If we compare its reproductive power with the amount of nutriment contained in it, we find that one acre of average land sown with potatoes will support twice as many persons as the same quantity of land sown with wheat. The consequence is, that in a country where men live on potatoes, the population will, if other things are tolerably equal, increase twice as fast as in a country where they live on wheat. And so it has actually occurred: until a few years ago, the population in Ireland, in round numbers, increased annually three per cent.; the population of England during the same period increasing one and a half per cent.—Buckle’s History of Civilization.