MARCH 29, 1901. ] 
pheric electricity. A bibliography accompa- 
nies the article (Ueber neuere Untersuchungen 
auf dem Gebiete der atmosphirischen Hlek-- 
tricitat). R. DEC. WARD. 
YELLOW FEVER.* 
1. Sufficient search reveals the presence of a 
fine small bacillus in the organs of all fatal 
cases of yellow fever. We have found it in 
each of the fourteen cadavers examined for the 
purpose. In diameter the bacillus somewhat 
recalls that of the inflluenza bacillus; seen in 
the tissues ; it is about 4, in length. 
2. This bacillus has been found in kidney, in 
spleen, in mesenteric portal and axillary } lym- 
phatic glands, ete., taken from yellow fever 
cadavers directly after death. In the contents 
of the lower intestine apparently the same 
bacillus is found often in extraordinary prepon- 
derance over other micro-organisms. Prepara- 
tions of the pieces of ‘mucus,’ which are 
usually, if not always, present in yellow fever 
stools, at times may almost present the appear- 
ance of ‘pure culture.’ 
3. Preparations of the organs usually fail to 
show the presence of any other bacteria, whose 
absence is confirmed by the usual sterility of 
cultivation experiments. 
4. It is probable that this same bacillus has 
been met with, but not recognized by three other 
observers. Dr. Sternberg} has mentioned it ; 
and he has also recorded the finding of similar 
organisms in material derived from Drs. Domin- 
gos Freire and Carmona y Valle; but he did 
not recognize its presence frequently, probably 
on account of the employment of insufficiently 
stringent staining technique. 
5. It is probable that recognition has not 
been previously accorded to this bacillus by 
reason of the difficulty with which it takes up 
stains (especially methylene-blue), and by rea- 
son of the difficulty of establishing growths on 
artificial media. 
* Abstract of interim report by Herbert E. Durham 
and (the late) Walter Myers to the Liverpool School 
of Tropical Medicine. 
+ We find these constantly enlarged and much in- 
jected, though whether this is specific we are not able 
to say. 
-f Report on Etiology and Prevention of Yellow Fever, 
1890. 
SCIENCE. 
513 
6. The most successful staining reagent is 
carbolic fuchsin solution (Ziehl), diluted with 
5-per-cent. phenol solution (to prevent acci- 
dental contamination during the long staining 
period) immersion for several hours, followed 
by differentiation in weak acetic acid. Two 
hours staining period may fail to reveal bacilli, 
which appear after 12 to 18 hours. The bacilli 
in the stools are often of greater length than 
those in the tissues, and they may stain rather 
more easily; naturally the same is true of cul- 
tures. 
7. Since the bacilli are small and compara- 
tively few in numbers they are difficult to find. 
To facilitate matters at our last two necropsies 
(14th and 15th) a method of sedimentation has 
been adopted. A considerable quantity of or- 
gan juice is emulsified with antiseptic solutions, 
minute precautions against contamination and 
for control being taken ; the emulsion is shaken 
from time to-time and allowed to settle. The 
method is successful and may form a ready 
means of preserving bacteria-containing mate- 
rial for future study. The best fluid for the 
purpose has yet to be worked out; hitherto 
normal saline with about one-fifth per cent. 
sublimate has been employed. 
8. Pure growths of these bacilli are not ob- 
tained in ordinary aérobic and anaérobic cul- 
ture tubes. 
9. Some pure cultures have been obtained by 
placing whole mesenteric glands (cut out by 
means of the thermo-cautery) into broth under 
strict hydrogen atmosphere. Investigations 
into the necessary constitution of culture media 
for successful cultivation are in progress. 
10. Much search was made for parasites of 
the nature of protozoa. We conclude that 
yellow fever is not due to this class of parasite. 
Our examinations were made on very fresh 
organ juices, blood, etc., taken at various stages 
of the disease, with and without centrifugalisa- 
tion,* and on specimens fixed and stained in 
appropriate ways. We may add that we have 
sometimes examined the organs in a fresh state 
under the microscope within half an hour after 
death. 
11. The endeavor to prove a man-to-man 
* We have found this sometimes useful in examin- 
ing the blood of ague patients. 
