DR. LEGEAR'S STOCK BOOK. 85 



CHAPTER VII. 

 THE URINARY ORGANS. 



The urinary organs are, the kidneys, ureters (tubes leading 

 from the kidneys to the bladder), bladder, and urethra (tube 

 leading from the bladder through which the urine is expelled). 

 Their functions are to secrete the urine from the blood, and ex- 

 pel it from the body. The urine is a watery fluid holding 

 in solution a varying quantity of earthy salts, and a peculiar sub- 

 stance, urea, which, if not expelled from the body, acts as a blood 

 poison. The kidneys are very important organs of the body, and 

 have a very essential duty to perform; therefore, it is all-import- 

 ant that they be kept in proper working condition, and free from 

 disease. Certain affections, with imperfect nutrition or destruct- 

 ive waste of the bony tissues, tend to charge the urine with phos- 

 phates of lime and magnesia, and induce the formation of stone 

 and gravel. All general diseases of the system more or less affect 

 the kidneys by giving them extra work to do carrying off 

 the waste products and poisons of the disease. The kidneys are 

 located under the loins, one on each side of the backbone. The 

 bladder i,s located in the pelvic cavity, and it serves as a reservoir 

 for the urine. From the bladder leads the urethra, through 

 which the urine escapes. Below will be found a brief description 

 of the more important diseases of the urinary organs. 



NEPHRITIS INFLAMMATION OF THE KIDNEYS. 



Inflammation of the kidne} r s is not so common among the 

 lower animals as in man. It usually occurs in the chronic form, 

 being rarely met with in the acute form. Only one kidney may 



