154 STERILIZATION AND DISINFECTION 
When everything is in readiness the culture is added to the dis- 
infectant solutions with a sterile pipette in quantities of a tenth of 
a cubic centimeter to each dilution. . 
To add the culture, the seeding tube containing the disinfectant 
is removed from the water bath with the left hand and slanted at 
an angle of about 45°, and with the right hand the end of the pipette 
containing the culture is introduced and lightly touched against the 
side of the tube where the liquid has run away on account of the 
slanting. At the proper time the culture is allowed to run into the 
disinfectant solution, the pipette removed, the tube straightened up, 
gently shaken three times, and 
replaced in the water bath. The 
other tubes are done the same way 
in succession, and it will be found 
that fifteen seconds is ample time for 
each tube. By adding the culture 
to the disinfectant with a pipette 
touched against the side of the 
seeding tube, accurate measure- 
ments can be made and each tube 
receive exactly the same amount 
of “seeding,” which is not the case 
when the culture is added by the 
be drop.” 
If ten tubes are to be inocu- 
Fro, 44.—Cross-section of Water lated, only a few seconds will remain 
Bath Showing Seeding Tubes in 2fter inoculating the last tube before 
Place. a plant from the first tube will have 
to be made. 
The mixing tubes are not removed or disturbed in making the 
planting except to insert the loop or spoon into them, touch the botton, 
withdraw, and then make the plant in broth. Every effort is made to 
insert and withdraw the loops or spoons in a uniform manner. The 
loops and spoons are bent to an angle of about 45° where they are 
jointed to the shank, and therefore are always filled with the mixture 
when withdrawn from the seeding tubes. After making the plants 
the loops or spoons are flamed as already described. 
After an experiment is finished the date and any necessary details 
can be marked on one of the broth tubes.and the rack placed in the 
incubator at 37° C. for forty-eight hours. At the end of this time 
the results are recorded on a chart specially devised for the purpose. 
