480 PRACTICE OF PHYSIC. 



two diseases have been commonly distinguished by the grip- 

 ings being more violent in the dysentery ; and they are com- 

 monly less violent and less frequent in diarrhoea ; but as they 

 frequently do occur in this also, and sometimes to a consider- 

 able degree, so they do not afford any proper distinction. 



MCCCCLXVII. A diarrhoea is to be distinguished from cho- 

 lera chiefly by the difference of their causes ; which, in cholera, 

 is of one peculiar kind ; but in diarrhoea is prodigiously di- 

 versified, as we shall see presently. It has been common to 

 distinguish cholera by the evacuation downwards being of bili- 

 ous matter, and by this being always accompanied with a vom- 

 iting of the same kind ; but it does not universally apply, as a 

 diarrhoea is sometimes attended with vomiting, and even of 

 bilious matter. 



MCCCCLXVIII. The disease of diarrhoea, thus distin- 

 guished, is very greatly diversified ; but, in all cases, the fre- 

 quency of stools is to be imputed to a preternatural increase of 

 the peristaltic motion in the whole, or at least a considerable 

 portion, of the intestinal canal. This increased action is in 

 different degrees, is often convulsive and spasmodic, and at any 

 rate is a motus abnormis : for which reason, in the Methodical 

 Nosology, I have referred it to the order of Spasmi, and ac- 

 cordingly treat of it in this place. 



MCCCCLXIX. Upon the same ground, as I consider the 

 disease named Lientery to be an increased peristaltic motion 

 over the whole of the intestinal canal, arising from a peculiar 

 irritability, I have considered it as merely a species of diarr- 

 hoea. The idea of a laxity of the intestinal canal being the 

 cause either of lientery or other species of diarrhoea, appears 

 to me to be without foundation, except in the single case of 

 frequent liquid stools from a palsy of the sphincter ani. 



MCCCCLXX. The increased action of the peristaltic mo- 

 tion, I consider as always the chief part of the proximate cause 

 of diarrhoea : but the disease is further, and indeed chiefly, di- 

 versified by the different causes of this increased action, which 

 we are now to inquire into. 



MCCCCLXXI. The several causes of the increased action 

 of the intestines may be referred, I think, in the first place, 

 to two general heads. 



1 



