572 PRACTICE OF PHYSIC. 



degree without producing a plethora ad spatium in a great part 

 of the system of the aorta, and therefore a plethora ad molem 

 in the lungs, and in the vessels of the brain. 



MDCXXIII. In attempting the cure of polysarcia, I am 

 of opinion that the conjunction of plethora and obesity, in the 

 manner just now mentioned, should be constantly attended to ; 

 and when the morbid effects of the plethoric habit are threaten- 

 ed, either in the head or lungs, that blood-letting is to be prac- 

 tised : but at the same time it is to be observed, that persons 

 of much obesity do not bear blood-letting well ; and when the 

 circumstances I have mentioned do not immediately require 

 it, the practice upon account of obesity alone, is hardly ever 

 to be employed. The same remark is to be made with respect 

 to any other evacuations that may be proposed for the cure of 

 corpulency : for without the other means I am to mention, they 

 can give but a very imperfect relief; and, in so far as they 

 either empty or weaken the system, they may favour the return 

 of plethora, and the increase of obesity. 



MDCXXI V. Polysarcia, or corpulency, whether it depend 

 upon plethora or obesity, whenever it either can be considered 

 as a disease, or threatens to induce one, is to be cured, or the 

 effects of it are to be obviated, by diet and exercise. The diet 

 must be sparing ; or rather, what is more admissible, it must be 

 such as affords little nutritious matter. It must therefore be 

 chiefly, or almost only, of vegetable matter, and at the very ut- 

 most of milk. Such a diet should be employed, and generally 

 ought to precede exercise ; for obesity does not easily admit of 

 bodily exercise, which is, however, the only mode that can be 

 very effectual. Such, indeed, in many cases, may seem difficult 

 to be admitted ; but I am of opinion, that even the most cor- 

 pulent may be brought to bear it, by at first attempting it 

 very moderately, and increasing it by degrees very slowly, 

 but at the same time persisting in such attempts with great 

 constancy. 



" There is always a way of introducing exercise : if the 

 patient cannot walk twenty yards, he perhaps can walk ten, 

 which, by repeating, he will soon increase to eleven and twelve, 

 and so may be brought gradually to undergo any degree of 

 exercise. It will be ridiculous if patients will not submit to 



