Besides the famine-fever of Scotland in 1622-23, there was another associated thing which should not be left out of account. Before the famine and fever had begun in that country, the notorious Hungarian fever was raging in the Palatinate, and continued to rage for four years. “Hungarian fever” had become the dreaded name for war-typhus of a peculiar malignity and diffusive power. It had been so often engendered since the 16th century in campaigns upon Hungarian soil as to have become known everywhere under the name of that country. Its infection spread, also, everywhere through Europe; thus it is said to have even reached England in 1566, and again in 1589, although it is not easy to find English evidence of it for either year. It was this type of fever which broke out in the Upper Palatinate, occupied by troops of the Catholic powers, in 1620, and continued through the years 1621, 1622 and 1623; as the title of one of the essays upon this outbreak somewhat fantastically declares, it spread “ex castris ad rastra, ex rastris ad rostra, ab his ad aras et focos[52].” Was the epidemic constitution of “spotted ague” in England in 1623 and 1624 derived from the centre of famine-fever in Scotland, or from the centre of camp-fever in the Palatinate? In the last years of James I. communications were frequent with the latter country, and there was of course much intercourse with Scotland. The spotted fever or spotted ague of 1623-24, the plague of 1625, and the country agues of the same autumn make really a more instructive series of epidemic constitutions than any that fell under Sydenham’s observation, so instructive, indeed, that it has seemed worth while to revert to it for the sake of illustrating the doctrine of epidemics then in vogue. That doctrine made little of contagion from person to person; yet the idea of contagion was familiar, and had been so since medieval times. If we might assume contagion to explain such cases as those that occurred in the houses of squires and nobles, we might find a source of it either in the famine-fever of Scotland or in the war-fever of the Palatinate. But the teaching of the time was that it was in the air; and if the infective principle had been generated either in Scotland or on the upper Rhine it had diffused itself in some inscrutable way. The doctrine of epidemic constitutions seems strange to us; but some of the facts that it was meant to embrace are also strange to us. Were it not for an occasional reminder from influenza, we should hardly believe that any fevers could have travelled as the Hungarian fevers, the spotted fevers or “spotted agues” of former times are said to have done.