This volume is the continuation of ‘A History of Epidemics in Britain from A.D. 664 to the Extinction of Plague’ (which was published three years ago), and is the completion of the history to the present time. The two volumes may be referred to conveniently as the first and second of a ‘History of Epidemics in Britain.’ In adhering to the plan of a systematic history instead of annals I have encountered more difficulties in the second volume than in the first. In the earlier period the predominant infection was Plague, which was not only of so uniform a type as to give no trouble, in the nosological sense, but was often so dramatic in its occasions and so enormous in its effects as to make a fitting historical theme. With its disappearance after 1666, the field is seen after a time to be occupied by a numerous brood of fevers, anginas and other infections, which are not always easy to identify according to modern definitions, and were recorded by writers of the time, for example Wintringham, in so dry or abstract a manner and with so little of human interest as to make but tedious reading in an almost obsolete phraseology. Descriptions of the fevers of those times, under the various names of synochus, synocha, nervous, putrid, miliary, remittent, comatose, and the like, have been introduced into the chapter on Continued Fevers so as to show their generic as well as their differential character; but a not less important purpose of the chapter has been to illustrate the condition of the working classes, the unwholesomeness of towns, London in particular, the state of the gaols and of the navy, the seasons of dearth, the times of war-prices or of depressed trade, and all other vicissitudes of well-being, of which the amount of Typhus and Relapsing Fever has always been a curiously correct index. It is in this chapter that the epidemiology comes into closest contact with social and economic history. In the special chapter for Ireland the association is so close, and so uniform over a long period, that the history may seem at times to lose its distinctively medical character.

As the two first chapters are pervaded by social and economic history, so each of the others will be found to have one or more points of distinctive interest besides the strictly professional. Smallpox is perhaps the most suitable of all the subjects in this volume to be exhibited in a continuous view, from the epidemics of it in London in the first Stuart reigns to the statistics of last year. While it shares with Plague the merit, from a historical point of view, of being always the same definite item in the bills of mortality, it can be shown to have experienced, in the course of two centuries and a half, changes in its incidence upon the classes in the community, upon the several age-periods and upon town and country, as well as a very marked change relatively to measles and scarlatina among the infective scourges of infancy and childhood. For certain reasons Smallpox has been the most favoured infectious disease, having claimed an altogether disproportionate share of interest at one time with Inoculation, at another time with Vaccination. The history of the former practice, which is the precedent for, or source of, a whole new ambitious scheme of prophylaxis in the infectious diseases of men and brutes, has been given minutely. The latter practice, which is a radical innovation inasmuch as it affects to prevent one disease by the inoculation of another, has been assigned as much space in the chapter on Smallpox as it seems to me to deserve. Measles and Whooping-cough are historically interesting, in that they seem to have become relatively more prominent among the infantile causes of death in proportion as the public health has improved. Whooping-cough is now left to head the list of its class by the shrinkage of the others. It is in the statistics of Measles and Whooping-cough that the principle of population comes most into view. The scientific interest of Scarlatina and Diphtheria is mainly that of new, or at least very intermittent, species. Towards the middle of the 18th century there emerges an epidemic sickness new to that age, in which were probably contained the two modern types of Scarlet Fever and Diphtheria more or less clearly differentiated. The subsequent history of each has been remarkable: for a whole generation Scarlatina could prove itself a mild infection causing relatively few deaths, to become in the generation next following the greatest scourge of childhood; for two whole generations Diphtheria had disappeared from the observation of all but a few medical men, to emerge suddenly in its modern form about the years 1856-59.

The history of Dysentery, as told by the younger Heberden, has been a favourite instance of the steady decrease of a disease in London during the 18th century. I have shown the error in this, and at the same time have proved from the London bills of mortality of the 17th and 18th centuries that Infantile Diarrhoea, which is now one of the most important causes of death in some of the great manufacturing and shipping towns, was formerly still more deadly to the infancy of the capital in a hot summer or autumn. Asiatic Cholera brings us back, at the end of the history, to the same great problem which the Black Death of the 14th century raised near the beginning of it, namely, the importation of the seeds of pestilence from some remote country, and their dependence for vitality or effectiveness in the new soil upon certain favouring conditions, which sanitary science has now happily in its power to withhold. I have left Influenza to be mentioned last. Its place is indeed unique among epidemic diseases; it is the oldest and most obdurate of all the problems in epidemiology. The only piece of speculation in this volume will be found in the five-and-twenty pages which follow the narrative of the various historical Influenzas; it is purely tentative, exhibiting rather the disjecta membra of a theory than a compact and finished hypothesis. If there is any new light thrown upon the subject, or new point of view opened, it is in bringing forward in the same context the strangely neglected history of Epidemic Agues.

Other subjects than those which occupy the nine chapters of this volume might have been brought into a history of epidemics, such as Mumps, Chickenpox and German Measles, Sibbens and Button Scurvy, together with certain ordinary maladies which become epidemical at times, such as Pneumonia, Erysipelas, Quinsy, Jaundice, Boils and some skin-diseases. While none of these are without pathological interest, they do not lend themselves readily to the plan of this book; they could hardly have been included except in an appendix of miscellanea curiosa, and I have preferred to leave them out altogether. It has been found necessary, also, to discontinue the history of Yellow Fever in the West Indian and North American colonies, which was begun in the former volume.

I have, unfortunately for my own labour, very few acknowledgements to make of help from the writings of earlier workers in the same field. My chief obligation is to the late Dr Murchison’s historical introduction to his ‘Continued Fevers of Great Britain.’ I ought also to mention Dr Robert Willan’s summary of the throat-distempers of the 18th century, in his ‘Cutaneous Diseases’ of 1808, and the miscellaneous extracts relating to Irish epidemics which are appended in a chronological table to Sir W. R. Wilde’s report as Census Commissioner for Ireland. For the more recent history, much use has naturally been made of the medical reports compiled for the public service, especially the statistical.

September, 1894.