CERTAIX ABNORMAL CONDITIONS OP^ THE URINE. 713 



local changes occiirring in the kidney or at different parts ot 

 the mucous membrane of the urinary tract ; while by the 

 exercise of the same means, if not able certainly to determine 

 the existence of disease of other and distant organs, we often 

 find much assistance in forming our opinions and in directing 

 our attention to situations and conditions of disease which 

 otherwise we miofht not observe. 



CHAPTER LI. 



OF CERTAIN ABNORMAL CONDITIONS OF THE URINE. 



Without doing violence to the subject, and as likely to include 

 nearly all those abnormal conditions of the urine we may 

 encounter in our particular patient, we shall here regard the 

 unnatural state of the secretion under three considerable 

 groups or varieties : (1) Characters given to the secretion through 

 excess or deficiency, beyond moderation, of the normal consti- 

 tuents ; (2) Characters imparted by matters in solution not 

 usucdly present in health ; (3) Tlie existence of certain morbid, 

 urinary deposits. 



1. Characters given to the Secretion through Excess or Deficiency 

 of Normal Elements, a. Excess of Water. — Of this unnatural 

 condition we have frequent examples in the horse, notably in 

 the disease recognised by the terms ' Diabetes Insipidus,' or 

 'Hydruria,' and in other states which, as they do not reach the 

 same extent of discharge of watery urine, have not been dignified 

 with any distinctive appellation. 



In all these cases of excess of water, although the entire 

 bulk of the urine is largely increased, there may be no very 

 appreciable augmentation of the solid materials of the secretion; 

 no doubt in some, such augmentation does exist, particularly 

 during the earlier stages of the increased secretion. We know 

 that excess of water is favourable to the removal of the products 

 of tissue-waste, as also that with such sudden increase and out- 

 pouring of water from the malpighian capillaries, by washing 

 out the uriniferous tubes, there is augmentation for the time 

 of the sohd matters in the urine. Usually, however, although 

 we have obvious increase of the Avater, the solids of the dis- 



