26 
Chapter III 
The Detection of the Malaria Parasite 
N.B.—A stained specimen (Romanowsky) should always be used 
for the purpose of making a diagnosis as parasites are easily missed in 
fresh films. 
To Examine the Stained Film. —After staining 
and drying, the film is ready for examination. Canada- 
halsam and coverglass need not he applied. A drop of 
cedar-wood oil is placed upon the film, and the oil 
immersion lowered into it. 
Fix the right-hand end of the slide with a clip 
on the stage, and with the fine adjustment first focus 
upwards slightly, as the lens may be already too low. 
If the film does not come into view, focus down¬ 
wards, keeping the unfixed end of the slide constantly 
moving very slightly to and fro with the left hand 
until the film comes into focus. If this precaution is 
taken a lens should never be jammed against a slide 
or driven through a coverglass. 
Commence the examination at the edge of the 
film near the middle, and then proceed towards the 
points or tongues, for it is along the edge and especially 
in the tongues that parasites (if very scanty) will be 
found if present. 
After the examination is completed, if it be 
desired to keep the film, the cedar oil is dissolved off 
by dropping a little xylol over the film and allowing 
this to drain off. and then to dry. After drying the 
