DIET. 131 



greater risk of being assailed by disease. It is, therefore, very 

 imprudent to sleep with open windows, or, at least, with such as 

 admit a current of air to pass over the sleeping body. And yet 

 this is a practice generally followed, with a view to enjoying the 

 cool of the night. Sleeping in the open air has not the same 

 ill effects. 



Besides these general rules, there are others which are 

 specially applicable to persons living within the limits of marshy 

 places. The effluvia arising from such localities exercise their 

 influence on the natives as well as strangers ; and the suggestions 

 I am about to offer are intended for both classes of persons. 



Any individual dwelling near a marsh ought to make use of 

 animal food, drink beer and porter, or spirits and water in the 

 proportion of one pint of the former and thirty of the latter : 

 the water should be filtered through charcoal. If engaged in 

 rural avocations, before going out in the morning he should 

 take some strong coffee, chocolate, or tea, with a little bread ; in 

 fact, he ought never to commence his labours with an empty 

 stomach. Again, he should not venture out at an early hour 

 when the dew is still abundant on the field, or during rain, 

 unless dressed in coarse woollen garments — say serge trousers 

 and a flannel jacket : both should be made large. He should 

 not follow the practice of wearing socks, and, on coming home — 



j even for a short time — he should change his wet for dry shoes. 



I If possible, he should avoid exposure to the action of effluvia 

 either at sunrise or sunset, as they condense at night and seem 



! to evolve or disperse with renewed energy in the morning ; and, 

 as the human frame is more liable to be acted upon during 

 slumber, all outer entrances to dwellings ought to be closed 

 before sunset, and re-opened some time after sunrise — particu- 

 larly those of the sleeping-room; screens made of canvas, or 

 metallic sheets, should be also placed at the draughts of doors 

 and windows, as a protection against the introduction of 

 miasma. 



Individuals should be very careful in protecting themselves 

 against humidity, for I have come to the conclusion that this is 

 one of the most active causes of disease. It is humidity, and 

 not heat, which may be said to be productive of fever. Yellow 

 fever may arise during the rainy season, as also dysentery. 

 Many localities, under the same latitude, which enjoy the 



