IT is a biological commonplace that every species of animal (man included) tends to increase in numbers if left free to propagate without restraint. This restraint is, however, always forthcoming when the population reaches a certain degree of saturation, and in the case of the human race it has in the past taken three forms, namely, war, famine, and pestilence. During the fourteenth century there were seven famines in England, in which the people died like flies, and towards the close of the century the Black Death wiped out three-quarters of the population. We are familiar with the ravages of the Great Plague in London in 1666, during which 100,000 people died, but few realise that in the preceding century there were two similar visitations, and in the earlier one, which occurred in Elizabeth's reign, 65,000 people died. The Queen and Court fled to Windsor, and the Queen had a gallows erected in the market-place, and gave orders that every Londoner who appeared in the town should be hanged !