DISEASES OF THE URINARY ORGANS. 



By JAMES LAW, F. R. C. V. S., 

 Professor of Veterinary Science, etc., in Cornell University. 



The iirinaiy organs constitute the main channel through which are 

 excreted the nitrogenous or albuminoid iDrinciples, whether derived 

 directly from the food or from the muscular and other nitrogenized 

 tissues of the body. They constitute, besides, the channel through 

 which are thrown out most of the poisons, whether taken in by the 

 moutli or skin or develoxDcd in connection with faulty or natural 

 digestion, blood-forming, nutrition, or tissue destruction; or, finally, 

 poisons that are developed within the bod}" as the result of normal 

 cell-life or of the life of bacteria or other germs that have entered the 

 body from Vv-ithout. To a large extent, therefore, these organs are 

 the sanitary scavengers and purifiers of the system, and when their 

 functions are impaired or arrested the retained poisons quickly show 

 their presence in resulting disorders of the skin and connective tissue 

 beneath it, of the nervous system, or other organs. Nor is this influ- 

 ence one-sided. Scarcely an important organ of the body can suffer 

 derangement without entailing a corresponding disorder of the urinary 

 system. Nothing can be more striking than the mutual balance 

 maintained between the liquid secretions of the skin and kidneys dur- 

 ing hot and cold weather. In summer, when so much liquid exhales 

 through the skin as sweat, comparatively' little urine is passed, 

 whereas in winter, when the skin is inactive, the urine is correspond- 

 ingly increased. This vicarious action of skin and kidneys is usually 

 kept within the limits of health, but at times the draining ofC of the 

 water by the skin leaves too little to keej) the solids of the urine safely 

 in solution, and these are liable to crj'stallize out and form stone and 

 gravel. Similarly the passage in the sweat of some of the solids that 

 normally leave the bod}', dissolved in the urine, serves to irritate the 

 skin and produce troublesome eruptions. A disordered liver contrib- 

 utes to the i)roduction, under different circumstances, of an excess of 

 biliary coloring-matter, which stains the urine; of an excess of hip- 

 puric acid and allied products, which, being less soluble than urea 



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