IN MilDlCINE. 25 



at some of its uses to us in our daily practice. One of the most 

 frequent and important uses in practice is the examination of 

 deposits in the urine. The presence of blood-cells shows that 

 haemorrhage is going on in some parts of the urinary apparatus, 

 while pus-cells show that suppuration is going on, or that an 

 abscess has burst into the bladder or kidneys, and the presence of 

 different crystals in the urine are symptomatic of different consti- 

 tutional derangements. 



The presence of uric acid in the blood may be shown by 

 putting a little of the serum (or fluid part of the blood) in a 

 watch-glass, and adding a few drops of acetic acid. Two or three 

 fine filaments of silk are then placed in the mixture and allowed 

 to stand twenty-four hours, when the microscope reveals numerous 

 minute crystals of uric acid attached to the filaments. This, in 

 many instances, would give definite proof of the existence of 

 undeveloped gout in the system, and might often account for 

 various anomalous symptoms. 



Itch is demonstrated by finding the Acarus scabiei in its 

 burrows in the skin, and Ringworm by the presence of the spores 

 of Trychophyton tonsurans in the hair. 



The presence of intestinal worms may often be suspected from 

 the symptoms, but by microscopic examination we can detect the 

 ova, and so be certain of their existence, and by examination of a 

 small portion of muscle in a suspected case of Trichinosis we 

 could prove the presence or absence of Trichi?ice. An interesting 

 use of the microscope occurred during the recent formation of 

 the St. Gothard Tunnel. The workmen were attacked by a small 

 nematode worm — the Anchylostomum, which attached itself to the 

 upper part of the intestinal canal by a cup-like sucker, and 

 then proceeded to suck the blood, causing extreme weakness, 

 and in some cases death. When this disease was suspected in 

 any of the workmen, the correctness of the diagnosis was 

 proved by discovering the ova in their faeces. 



The expectoration of consumptive patients often contains 

 fragments of lung-tissue, which in some cases may be detected by 

 the microscope before positive signs of the disease can be 

 detected by other means. With reference to this. Dr. Andrew 

 Clarke says, " That the microscopical inspection of expectoration 



