472 THE URINE. 



H. Kostjurin found at the junction of the cortical and the medullary structure, 

 in the dog, a layer of muscle-fibers from which bundles pass in each direction. 



THE URINE.* 



THE PHYSICAL CHARACTERS OF THE URINE. 



The amount of urine in men is between 1000 and 1500 cu. cm. in 

 twenty-four hours; in women between 900 and 1200. There is a min- 

 imum between 2 and 4 a. m., a maximum in the morning and a second 

 maximum between 2 and 4 p. m. 



The amount of urine is diminished by profuse perspiration, diarrhea, thirst, 

 food deficient in nitrogen, reduction in the general blood-pressure, after profuse 

 hemorrhage, as a result of the action of certain poisons, such as atropin and mor- 

 phin, and in the presence of certain diseases of the structure of the kidney. The 

 minimum that may still be considered normal is between 400 and 500 cu. cm. 



The amount is increased by increase in the blood-pressure in general, or in the 

 distribution of the renal artery alone, by copious drinking, contraction of the 

 cutaneous vessels from the action of cold, the elimination of soluble diuretic 

 substances, such as urea, salts, and sugar through the urine, a diet rich in nitrogen, 

 as well as by certain medicaments, such as digitalis, juniper, squill, alcohol, etc. 

 Carbonated beverages increase the urine in the succeeding hour. 



The direct influence of the nervous system upon the amount of urine is also 

 familiar. In this category belongs the polyuria suddenly developed after nervous 

 perturbation, as, for instance, in hysterical persons, following epileptic attacks, 

 and also after pleasurable excitement, and finally the remarkable increase in 

 urinary secretion after injury of the floor of the fourth ventricle of the brain. 

 Nocturnal polyuria occurs in persons suffering from disease of the heart and the 

 kidneys, in cachectic states and in the presence of arterio-sclerosis. Neurasthenic 

 anuria of neurotic origin lasting from twelve to fifty-six hours is extremely 

 rare. The urine can be measured in graduated cylinders or flasks. 



The specific gravity of the urine varies between 1015 and 1025. 

 The minimum is observed after abundant ingestion of water, 1002; the 

 maximum after profuse sweating and marked thirst, 1040. In the new- 

 born the specific gravity falls considerably in the first few days, in 

 conformity with the progressive increase in the amount of nourishment 

 taken. The adult discharges per diem on the average i gram of solids 

 through the urine for every kilogram of body-weight. 



The determination of the specific gravity is made, with the urine at a tem- 

 perature of 16 C., by means of the urinometer (Fig. 144). If but a small amount 

 of urine is obtainable and it does not sufficiently fill the urinometer-cylinder the 

 urine is diluted with twice or thrice its volume of distilled water, and then the 

 last two figures on the urinometer are multiplied by two or three respectively. By 

 means of the formula of Trapp or Haeser the amount of solids contained in 1000 

 parts of urine can be estimated approximately from the specific gravity. Of the 

 number indicating the specific gravity, as, for instance, 1018, the last two figures 

 are taken, in this instance therefore 18, and multiplied by 2.33. The estimation 

 of the total solids can be made in a more trustworthy manner by evaporating 

 about 15 cu. cm. of urine in a weighed porcelain-dish over the water-bath and 

 subsequent complete drying in the air-bath at a temperature of 100 C. and cooling 

 over concentrated sulphuric acid. In this way some urea is decomposed into 

 carbon dioxid and escaping ammonia, in consequence of which the result is some- 

 what too low. 



The specific gravity depends naturally upon the amount of water in the 

 urine. The urine of the morning (urina noctis) is most concentrated, that is, 

 heaviest, because water is absorbed from the bladder after the urine has been 



* The illustrations are taken in part from Ultzmann and Hoffmann's Atlas of 

 Urinary Sediments. 



