114 
Effort was made to obtain from persons who had had typhoid in 
previous years, and with whom the cases had been in association during 
the thirty days prior to onset of illness, specimens of feces for bacte- 
riological examination. Thirty-two such specimens, obtained from 
persons who had had t^’^^hoid from six months to twenty years pre- 
vious, were examined and all were negative for the typhoid bacillus. 
Beside these there were examined in the course of the intensive 
study in special districts specimens of feces from 71 persons who had 
had typhoid fever from one to ten years preAnous and all were negative 
for the t;\’p)hoid bacillus. (See Table Xo. 3, page 16.) 
With a view to forming some idea of how many persons in Wash- 
ington during the typhoid fever season are bacillus carriers we had 
collected and examined, from July 16 to Xovember 8, 1,014 specimens 
of feces and 26 specimens of urine from 993 persons living in 32 blocks 
of the city. The method followed in making these examinations was 
as follows: 
METHOD OF EXAMINING FECES FOE THE TYPHOID BACILLHS. 
The specimens are collected in 2-ounce wide-niouth cork-stoppered 
bottles. Each bottle is accompanied by a piece of wood to be used 
as a spatula. The bottles and spatulas are sterilized before distribu- 
tion. In collecting the specimens instructions are given to place a 
small quantity of feces about the size of a walnut into the bottle with 
the wooden spatula, replace the cork, and label at once with the name 
and date. The bottles are distributed throughout the day and col- 
lected next morning and brought to the laboratory as soon as practi- 
cable. 
About 10 c. c. of sterile bouillon is poured into each bottle and 
agitated. This bouillon is now poured off into a conical graduate 
and allowed to stand one-half to one hour, during which time heavy 
particles settle, and it is supposed the upper layers of such a fluid 
will be more apt to contain motile organisms like the typhoid bacillus. 
A bent glass rod is now dipped into the upper layer of the bouillon 
and used to streak five Endo plates. These are incubated 24 hours, 
at the end of which time the small transparent colorless dewdroplike 
colonies are fished and planted into bouillon These bouillon tubes 
are incubated 24 hours. A drop or two of horse serum of high agglu- 
tinatmg power for B. typhosus is then added to the 24-hour old bouil- 
lon growth. 
With a serum of very high agglutinating power definit-e clumping 
is evident to the naked eye usually within 15 to 20 minutes and 
almost invariably within an hour. Positive growths which fail to 
agglutmate with typhoid agglutmin should be tested with para- 
tAqihoid serums. 
