89 
For further details of the manner in which the blood serum was 
obtained and the filtration performed, see the above records of Filo- 
mena Martinez. 
Peredo was carefully watched from the hour he was injected, but 
he remained in good health, and no deviation from the normal was 
detected. 
His temperature was taken every four hours during the night and 
day, both before and following the injection, as will be seen by the 
temperature chart. No symptoms developed. 
His blood was examined daily for plasmodium, but none was found. 
The result of this injection must therefore be considered negative. 
Ten days later he was again injected with filtered malarial blood 
under different circumstances, and with positive results. 
At 1.40 p. m., November 6, he was given an intravenous injection 
of the blood of Andres Mendez, passed through the same Berkefeld 
filter as before. Mendez was suffering with a double tertian in¬ 
fection; his blood was drawn during his chill and before the height 
of the paroxysm, as will be seen by reference to the temperature chart 
(page 85). 
Thinking that allowing -the blood to clot four or five hours in the 
ice chest in order to obtain a clear serum for filtration might be too 
severe a tax upon the vitality of the malarial parasite, we this time 
defibrinated the blood as quickly as possible, diluted it as before with 
an equal volume of physiological salt solution, and filtered it through 
the same Berkefeld filter in the same manner as was done with blood 
of Filomena Martinez. 
As soon as 9 cc. of the filtrate could be obtained it was injected into y 
the basilic vein of the right arm of Louis Peredo. This injection took 
place at 1.40 p. m. 
About thirtj^-five minutes after receiving the injection he began 
having chilly sensations and headaches, and presently went to bed 
covering himself with his blanket (2.25 p. m.). Five minutes later 
(2.30) he was having a violent chill, his teeth chattering so that we 
could not trust the thermometer in his mouth. The rigor of the entire 
body was so marked that there was difficulty in taking the radial 
pulse. The face was pale, and at this time he vomited most of the 
dinner he had eaten a short time before receiving the injection. 
The patient complained of headache, which he localized at the fore¬ 
head and occiput; says he felt cold and had pains in the knees. At 
this time the skin was dry. The chill lasted somewhat over half an 
hoar. 
At 3 p. m. the patient had transient chilly creeps, very slight rigor. 
At 3.15 p. m. he said he felt “ warm inside,” and all sense of chilli¬ 
ness had disappeared; still has headache. 
At 3.25 p. m. he complained of marked pain in the legs. 
