PLAGUE OF LONDON, THE GREAT, the epidemic of bubonic plague that afflicted the capital through 1665, the worst visitation of that disease this Commonwealth's records show since the outbreaks of the previous century and, on the returns this contributor has examined, the last of any comparable severity the City has suffered before the present edition's own date. The weekly bills of mortality kept by the parish clerks throughout the visitation, a documentary series this contributor's own statistical training finds remarkably complete for so early a date, return a total mortality for the year of some sixty-eight thousand eight hundred deaths attributed directly to the plague, out of a City population the same bills estimate at some four hundred and sixty thousand — a mortality rate of close upon one in seven, concentrated overwhelmingly, as the parish returns make plain, in the poorer and more crowded riverside parishes rather than the wealthier wards to the west, whose residents possessed, in the plainest economic sense, the means to remove themselves to the country that the poorer parishes' residents did not.
The mortality bills themselves, examined as a body rather than singly, supply this contributor with a cleaner statistical record of the disease's own progress than the narrative accounts generally attempt: the weekly toll rose from single figures in the spring to above seven thousand in a single week of September at the visitation's height, before falling away sharply with the first hard frosts of the following winter, a seasonal pattern this Commonwealth's physicians did not fully understand at the time and which this contributor's own training in the modern science of disease finds a good deal more comprehensible than they could have. The bills' own categories — plague, consumption, the several fevers, "rising of the lights," and a miscellany the clerks recorded under headings a modern physician would find it difficult to translate with any confidence — are themselves a document of some interest to the historian of the science this Commonwealth's medical faculties have since made of what were, in 1665, still very largely the parish clerk's own untrained categories.
The visitation was the last of its severity the capital has suffered, the improved drainage and the wider streets built after the following year's Fire (q.v.) being credited, by this Commonwealth's own physicians, with a good deal of the City's subsequent immunity, though this contributor's own reading of the bills for the intervening two and a half centuries suggests the credit is owed rather more to the general retreat of the disease across the whole of northern Europe in the same period than to any particular virtue of London's own rebuilding. (M. S. W.)