MEDICAL WORK WITH MICROSCOPE 



it was thought that the disease malaria was caused 

 by the damp air of low-lying land, in fact the word 

 malaria is derived from two Italian words meaning 

 bad air. It was not till the advent of the micro- 

 scope that the true cause of the disease was learned 

 and the discovery was made that the only connec- 

 tion between the malady and dampness is that the 

 mosquitoes which carry the disease can only thrive 

 in damp situations. 



Medical work with the microscope also entails a 

 study of external and internal parasites of man 

 other than those which infest the blood. Some of 

 the larger human parasites we know only too 

 well, they force their unpleasant attentions upon 

 us from time to time, but fortunately they are not 

 as a rule serious and are soon got rid of. The 

 cleanest of us, in these days of universal travel, 

 cannot avoid the visitations of the lively flea, he 

 is at worst an annoying companion, but he has a 

 cousin who is responsible for the passing of the 

 germs of the dreaded plague from rats to man. 

 Plague long remained a mystery, which, without 

 the help of the microscope, would probably have 

 remained unsolved to this day. Many of these 

 apparently harmless blood-sucking insects may 

 prove to be disease carriers, as medical knowledge 

 and microscopic investigation is brought to bear 

 upon them. 



The majority of the smaller external parasites are 

 beyond the reach of the amateur microscopist. A 

 number of course are available to medical students, 



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