Chapter II 
To Prepare Blood Films 
To Clean Slides .—Slides should be dipped in water 
and rubbed dry and clean with a soft cloth, e.g ., a clean 
handkerchief. If a perfectly clean slide is required, 
heat it £ red hot ’ over a flame ; in this way grease is 
completely removed. 
Before proceeding to take specimens of blood, the 
prepared slides may be placed in a small pocket slide 
box or wrapped in a sheet of clean note paper. 
To Clean the Patienfs Finger .—If the finger of 
one’s subject is obviously dirty, and especially if damp 
with sweat, the finger should be wiped with a cloth. 
If considered necessary, precautions may be taken to 
avoid all skin contaminations by the use of soap and 
water, alcohol, and ether, but in ordinary examinations 
for malarial parasites this is quite unnecessary. 
To make Dry Films .—The simplest and by far the 
best way of making films is by the use of no other 
apparatus than— 
1. A straight surgical needle about two inches in 
length with the eye cut off. 
2. Clean glass slides. 
When the drop of blood reaches the size of the 
head of a small pin, touch it with the slide about one- 
third inch from the far end. Now lay the shaft of the 
needle across the drop of blood. After waiting about 
a second, that is until the drop spreads between the 
slide and the needle ; the needle is evenly and not too 
