62 



(4) Organic constituents, as when glairy from albumen coagulable by 

 strong nitric acid and boiling, -when cliarged with microscopic casts of 

 the uriuiferous tubes, with the eggs or bodies of worms, with sugar, 

 blood, or bile. (5) In its salts, which may crystalize out spontaneously, 

 or on boiling, or on the addition of chemical re-agents. 



Albuminous urine in the horse is usually glairy, so that it may be 

 drawn out in threads, but its presence can always be tested as follows: 

 If the liquid is opaque, it may be first passed through filter paper; if 

 very dense and already precipitating its salts, it may be diluted with 

 distilled water ; add to the suspected liquid acetic acid drop by drop 

 until it reddens blue litmus paper; then boil gently in a test tube; 

 if a precipitate is thrown down, set the tube aside to cool and then add 

 strong nitric acid. If the precipitate is not dissolved it is albumen; if 

 dissolved it was probably urate or hippurate of ammonia. Albumen is 

 normally present in advanced gestation; abnormally it is seen in dis- 

 eases in which there occurs destruction of blood globules (anthrax, low 

 fevers, watery states of the blood, dropsies), in diseases of the heart 

 and liver which prevent the free escape of blood from the veins and 

 throw back venous pressure on the kidneys, in inflammation of the 

 lungs and pleuraB, and even tympany (bloating), doubtless from the 

 same cause, and in all congestive or inflammatory diseases of the kid 

 neys, acute or chronic. 



Casts of the uriniferous tubes can only be seen by placing the sus- 

 pected urine under the microscope. They are usually very clastic and 

 mobile, waving about in the liquid when the cover-glass is touched, and 

 showing a uniform clear transparency (waxy) or entangled circular 

 epithelial cells or opaque granules or flattened red blood globules or 

 clear refrangent oil globules. They may be even densely opaque from 

 crystals of earthy salts. 



Pus cells maybe found in the urine associated with albumen, and 

 are recognized by clearing up, when treated with acetic acid, so that 

 each cell shows two or three nuclei. 



DIURESIS — POLYURIA — DIABETES INSIPIDUS— EXCESSIVE SECRETION 



OF URINE. 



This consists in an excessive secretion of a clear, watery urine of a 

 low specific gravity (1.007) with a correspondingly ardent thirst, a rap- 

 idly advancing emaciation, and great loss of strength and spirit. 



Its causes may be any agent, medicinal, alimentary, or poisonous, 

 which unduly stimulates the kidneys; the reckless administration of 

 diuretics, which form such a common constituent of quack horse-powders; 

 acrid diuretic plants in grass or hay; new oats still imperfectly cured; 

 an excess of roots or other very watery food ; a full allowance of salt to 

 animals that have become inordinately fond of it ; but, above all, feeding 

 on hay, grain, or bran which has not been properly dried and has be- 

 come musty and permeated by fungi. Thus bay, straw, or oats secured 



