2l6 VETERINARY HOMCEOPATHY. 



branches from the spinal cord, and the desire is responded to by 

 the action of special nerves upon certain muscular fibres, which go 

 to make up the walls of the bladder, and therefore these muscular 

 fibres contract and in this way make the organ itself smaller, and 

 so the urine is forced out into the urethra and from thence dis- 

 charged as hereinbefore explained; other influences are brought 

 to bear in assisting the bladder to empt)' itself, but this will suffice 

 for the object in view, namely, to supply a cursory glance of the 

 function of urination. In order that the importance of obtaining 

 an intelligent appreciation of this subject may be impressed upon 

 the reader, it may be well to state, as shortly as possible, the prin- 

 cipal constituents of urine; and as we proceed it is hoped that it 

 will be discovered this has an important bearing upon the health 

 of horses, as observations of the appearance of urine, so far as 

 regards color and consistence are made. In the first place, the 

 specific gravity of the horse's urine averages 1045; the range 

 varies from 1 01 6 to 1060, the variations depend in a great measure 

 upon the mode of feeding as well as upon diseased conditions; the 

 diet also has a bearing upon the condition of urine whether the 

 same gives an acid or an alkaline reaction upon testing, a process 

 that furnishes valuable aid in selecting a drug under certain con- 

 ditions. The constituent composition of urine in health is ap- 

 proximately made up of water, urea and uric acid, which are de- 

 composition products of food and of the tissues of the body; hippuric 

 acid deriv^ed chiefl}^ from food; coloring and aromatic matters, and 

 salts, among which the phosphates abound. Much greater care 

 in observing the state of the urine is called for than is generally 

 exhibited during periods of illness, and there are several points 

 calling for special consideration; for instance, urine may have 

 either an excess or deficienc)^ of the watery constituents; an excess 

 of water may under certain conditions be favorable, as it serves to 

 wash away from the tubes of the kidneys any accumulation of 

 solid matter that has collected during disease; on the other hand 

 it may be an evidence of disease itself, as in one form of diabetes. 

 Then, with regard to apparent deficiency of water, it ma)' be due 

 to the fact of the horse having been submitted to hard work in 

 hot weather causing considerable perspiration; or the increase of 

 urea and other solid constituents ma)- be larger without a relative 

 increase in the water; in both instances the alteration may take 



