EPIDEMIC DIARRHCEA 309 



iiection not less instructive, perhaps more so, than its rise. It 

 coincides with the decline of the temperature recorded by the 4-foot 

 earth thermometer, which temperature declines very much more 

 slowly than the atmospheric temperature, or than that recorded by 

 the 1-foot thermometer; so that the epidemic mortality may con- 

 tinue (although declining) long after the last-mentioned temperatures 

 have fallen greatly, and may extend some way into the fourth 

 quarter of the year. The atmospheric temperature and the tempera- 

 ture of the more superficial layers of the earth, is little if at all 

 apparent until the temperature recorded by the 4-foot earth ther- 

 mometer has risen as stated above ; then their influence is apparent, 

 but it is a subsidiary one." 



In addition to these conditions of soil, Ballard and other workers 

 have concluded that insanitation in the widest sense of the term 

 favours epidemic diarrhcea. Density of population or houses upon 

 an area, unclean soil, dusty surfaces, bad light, absence of ventilation, 

 maternal neglect, etc., all have a share in creating an environment 

 favourable to the disease. As we have seen, Del^pine, like Ballard, 

 attributes the disease in large measure to milk. Ballard believed 

 that milk gained its infection by unsuitable storage and by the mode 

 in which it was used. He found that " infants fed solely from the 

 breast are remarkably exempt from fatal diarrhoea ; that infants fed 

 in whatever way with artificial food to the exclusion of breast milk 

 are those which suffer most heavily from fatal diarrhcea; that 

 children fed partially at the breast and partially with other kinds 

 of food, suffer to a considerable extent from fatal diarrhoea, but very 

 much less than those brought up altogether by hand ; and that, as 

 respects the use of ' the bottle,' it is decidedly more dangerous than 

 artificial feeding without the use of the bottle." This view has been 

 confirmed by Newsholme, Niven, Eichards, the writer, and others. 



Dr N'ewsholme of Brighton has published an interesting paper 

 on the causation of epidemic diarrhoea. Some of his chief conclusions, 

 which are now widely accepted, may be added : — 



"(1) Epidemic diarrhoea is chiefly a disease of urban life. (2) 

 Epidemic diarrhoea as a fatal disease, is a disease of the artisan and 

 still more of the lower labouring classes to a preponderant extent. 

 This is probably largely a question of social status iper se ; that is, 

 it is due to neglect of infants, uncleanly storage of food, industrial 

 occupation of mothers, etc. (3) Towns which have adopted the 

 water-carriage system of sewerage have, as a rule, much less diarrhoea 

 than those retaining other methods of removal of excrement. (4) 

 Towns with the most perfect scavenging arrangements, including the 

 methods of removal of house refuse, have the least epidemic diarrhoea. 

 It has recently been suggested that epidemic diarrhoea is due to 

 surface pollution derived from street dust, particularly dried horse- 



