490 PRACTICE OF PHYSIC. 



pending upon irritation, though it may be for some time suspend- 

 ed by opiates, yet always returns very soon. It is only by tak- 

 ing off irritability that opiates are useful in diarrhoea ; and, 

 therefore, when the disease depends upon an increase of irrita- 

 bility alone, or when, though proceeding from irritation, that 

 irritation is corrected or exhausted, opiates are the most useful 

 and certain remedy. And though opiates are not suited to cor- 

 rect or remove an irritation applied, they are often of great bene- 

 fit in suspending the effects of that irritation whenever these 

 are violent : and, upon the whole, it will appear, that opiates 

 may be very frequently, and with great propriety, employed in 

 the cure of diarrhoea. 



CHAP. XII. OF THE DIABETES. 



MDI V. This disease consists in the voiding of an unusually 

 large quantity of urine. 



As hardly any secretion can be increased without an increased 

 action of the vessels concerned in it, and as some instances of 

 this disease are attended with affections manifestly spasmodic, I 

 have had no doubt of arranging the diabetes under the order of 

 Spasmi. 



MDV. This disease is always accompanied with a great de- 

 gree of thirst, and therefore with the taking in of a great quan- 

 tity of drink. This in some measure accounts for the very ex- 

 traordinary quantities of urine voided : but still, independent of 

 this, a peculiar disease certainly takes place ; as the quantity 

 of urine voided does almost always exceed the whole of the 

 liquids, and sometimes the whole of both solids and liquids, taken 

 in. 



MDVI. The urine voided in this disease is always very clear, 

 and at first sight appears entirely without any colour ; but, 

 viewed in a certain light, it generally appears to be slightly 

 tinged with a yellowish green, and in this respect has been very 

 properly compared to a solution of honey in a large proportion 

 of water. 



Examined by the taste, it is very generally found to be more 



