650 PRACTICE OF PHYSIC. 



MDCCXCIV. It must however be allowed, that the princi- 

 pal circumstance in causing scurvy, is the living very much and 

 very long upon animal food, especially when in a putrescent 

 state ; and the clear proof of this is, that a quantity of fresh 

 vegetable food will always certainly prevent the disease. 



MDCCXCV. While it has been held, that, in those circum- 

 stances in which scurvy is produced, the animal food employed 

 was especially hurtful by its being of difficult digestion, this 

 opinion has been attempted to be confirmed, by observing, that 

 the rest of the food employed in the same circumstances was 

 also of difficult digestion- This is supposed to be especially 

 the case of unfermented farinacea, which so commonly makes a 

 part of the sea-diet. But I apprehend this opinion to be very 

 ill-founded ; for the unfermented farinacea, which are in a great 

 proportion the food of infants, of women, and of the greater 

 part of mankind, can hardly be supposed to be food of difficult 

 digestion : and with respect to the production of scurvy, there 

 are facts which show, that unfermented farinacea, employed in 

 large proportion, have had a considerable effect in preventing 

 the disease. 



MDCCXCVI. It has been imagined, that a certain impreg- 

 nation of the air upon the sea had an effect in producing scurvy. 

 But it is altogether improbable ; for the only impregnations 

 which could be suspected, are those of inflammable or mephitic 

 air ; and it is now well known that these impregnations are 

 much less in the air upon the sea than in that upon the land ; 

 besides, there are otherwise many proofs of the salubrity of the 

 sea-air. If, therefore, sea-air have any effect in producing 

 scurvy, it must be by its sensible qualities of cold or moisture. 



MDCCXCVII. That cold has an effect in favouring the 

 production of scurvy, is manifest from hence, that the disease 

 is more frequent and more considerable in cold than in warm 

 climates and seasons ; and that even warm clothing has a con- 

 siderable effect in preventing it. 



MDCCXCVIII. Moisture may in general have an effect in 

 favouring the production of scurvy, where that of the atmos- 

 phere in which men are placed is very considerable ; but the or- 

 dinary moisture of the sea-air is far from being such. Probably 

 it is never considerable, except in the case of unusual rains ; 



