35 



thromboses, emboli, edemas, anemias, etc., from vaso-motor trou- 

 bles changing simultaneously the filter, the liquids which filter,, 

 with regard to pressure and velocity. 



Albuminous urine is usually of light color and low specific 

 gravity. It may occasionally be dark and dense, due to other in- 

 gredients, or to concentration. 



Under particular conditions of fatigue or disease albumin 

 may appear in the urine. 



Temporary albuminuria is sometimes induced by a cold 

 bath, especialty in persons prone to kidney disease, and it has 

 been observed after excessive muscular exercise, as in the urine 

 of soldiers after a prolonged march. 



Any cause which leads to an increased blood pressure in the 

 kidneys tends to induce albuminuria, and many of the cases in 

 which it is the result of disease may be traced to this cause. Al- 

 buminuria is a constant accompaniment of the nephritis follow- 

 ing scarlet fever and may occur to a less extent in pneumonia, 

 typhoid and diphtheria. It may also occur in diabetes, and is 

 then a highly unfavorable symptom. 



In every case the urine must be clear before testing, by 

 filtering it carefully; also take the specific gravity.* In addi- 

 tion to the suspected urines make control tests on the normal for 

 comparison. 



Heat Test. Heat about 5 cc. of the urine to the boil- 

 ing point in a test tube. Note the slightest turbidity. If 

 present it will be due to albumin or earthy phosphates. In 

 horse urine the precipitate may be due to driving off CO, 

 and precipitation of lime, etc., not phosphates. Add 

 slowly a few drops of acetic acid (or nitric). If due to 

 the phosphates the urine becomes clear, if the turbidity 

 remains it is albumin. Care must be taken, in the addition 

 of the acid after boiling, to note the effect after each drop 

 is added and to go on adding until there is no doubt that 

 the urine is distinctly acid. If only a trace of albumin is 

 present and too much acid is added the albumin may be 

 converted into acid albumin and remain in solution. Heat 

 does not coagulate acid albumin. Add a little acetic acid 

 to dissolve any phosphates and heat again. 



* If a pathological urine is not available, a little blood serum added 

 to the normal urine will give satisfactory tests. 



