198 SECTIONAL ADDRESSES. 
natural defect. On the other hand, certain of the scourges of our ancestors 
have practically disappeared, especially some of the infectious diseases. 
Leprosy and plague long ago ceased their ravages, typhus and famine 
fever vanished, save for isolated cases in later Victorian times, enteric 
fever has lessened nearly to the vanishing point, and even infantile 
diarrhcea is becoming less year by year. Most, if not all, of these diseases 
may be communicated by animal agencies, either by direct inoculation 
from bites or by secondary contamination. The louse, the bug and the 
flea, common until recent years, are succumbing to the newer tradition 
and meaning of cleanliness which has followed universal education, the 
medical inspection of scholars, and the action of public health authorities ; 
the fly, an indirect agent, is being eliminated by improved sanitation, and 
the gradual disappearance of horse transport in our cities. As the changes 
proceed more rapidly in the towns the approximation of their health 
conditions to those in rural areas follows. 
Epidemic diseases have always attracted more notice from the historian 
owing to the wide extent of the resulting evils, so that much is written 
concerning the plague, the sweat, gaol fever and smallpox compared with 
more common disorders of life. Some of these have appeared in earlier 
days to exert some selective influence, though this selection depended 
rather on the mode of transmission of the disorder. Any disease trans- 
mitted, whether by vermin or from case to case, would be more prevalent 
under conditions in which the population were closely massed, and at 
periods or under conditions in which either the facilities or the sentiment 
for cleanliness were lacking. The plague, save in its first pandemic out- 
bursts as the ‘ Black Death,’ was mainly a disease of the poorer classes in 
the towns, in each epidemic affecting especially the worst housed, worst 
fed and least cleanly. Sporadic outbursts in rural areas followed the intro- 
duction of infection from without, as was well recognised by villagers who 
forcibly endeavoured to prevent the entrance of travellers from affected 
areas. Gradual changes in habits and domestic furnishing which reduced 
the breeding-places of rats and fleas were followed by the extinction of the 
plague. The sweat, it was noted in Tudor times, differed in its incidence ;** 
Kock said of the 1529 pandemic ‘the poor people and those living in 
cellars and garrets were free from sickness,’ while Renner noted “it went 
most among the rich people.’ This tradition, or a continuance of similar 
phenomena, must have remained, for we find in ‘ Measure for Measure’ ** 
Mistress Overdone says, ‘ Thus, what with the war, what with the sweat, 
and what with the gallows, [am custom-shrunk.’ It was noted over a long 
period that whereas typhus, gaol fever, and the like were always present 
among the poorer classes, the greater mortality followed outbreaks 
among healthier individuals, who had lived an open life, such as soldiers 
brought back to barracks after a campaign in the field, sturdy felons newly 
flung into gaol, or, as in the Irish famines, magistrates and relief workers 
whose duty carried them into the haunts of the disease. In the case of the 
‘Black Assizes,’ when judges and jurors succumbed but the prisoners 
escaped lightly, the phenomenon was ascribed to the latter being inured to 
22 Creighton, l.c., p. 268, with reference to Gruner, Scriptores de sudore Anglico 
superstites, pp. 444-448. 
23 Acti., Se 2 
