1910. ] Complement Deviation in Mouse Carcinoma. 361 
_ Serum was obtained from mice affected with mouse tumour by killing 
these animals with ether, exposing the heart with antiseptic precautions, 
puncturing the right ventricle with a sterilised glass pipette provided with a 
eapillary point which was pushed into the right auricle. With the aid of a 
rubber teat blood was sucked into the pipette and transferred to a steri- 
lised centrifugal tube, in which it was allowed to coagulate. The latter was 
then centrifugalised, the supernatant serum pipetted off, and inactivated by 
heat as above described. The amount of serum obtained from the mouse 
- ranged from 0:1 c.c. to 03 c.c. For use in control experiments, serum was 
obtained by the same procedure from normal mice. The sera were not 
employed for experiment until the lapse of 24 hours after inactivation. 
Owing to the small amount of serum obtainable from the mouse, it was 
necessary to deal with very small quantities of the fluids used for experi- 
ment. To this end capillary pipettes were prepared, which were graduated 
in hundredths of a c.c., and were capable of delivering amounts as small as 
0-003 c.c. to 0001 ¢.c. The graduation of the pipettes was effected by deter- 
mining the diameter of the capillary portion with the aid of a microscope 
provided with an eyepiece micrometer. From this the sectional area of the 
capillary tube was determined, and the length corresponding to any desired 
number of cubic millimetres calculated. The tubes were so selected that the 
length corresponding to 0:01 ¢.c. was from 1 cm. to 2cm. The mixtures of 
fluids employed in Tables I to IV were preserved in small tubes of about 
5 mm. internal diameter. 
The actual testing was carried out in the following way :—In the first 
place a number of tubes were prepared containing sensibilised red cells. To 
this end, into each tube 0:02 c.c. of the inactivated serum of a rat into which 
the red blood cells of the rabbit had been injected as above described was 
placed, and then 0-02 c.c. of the suspension of the red blood cells of the rabbit, 
the mixture being kept at 37° C., with occasional shaking, for one hour and 
a-hali. At the end of this time the fluid part of the mixture was removed 
by means of a capillary pipette from the red cells which had been allowed to 
fall to the bottom of the tube. 
The tubes containing sensibilised red cells were now arranged in four 
groups (cf. Tables I to IV). To the tubes in each group complement was 
added in amounts ranging from 0°001 c.c. to 0°081 ¢.c. To each of the tubes 
of the first group 0°06 c.c. of a 0°85-per-cent. sodium chloride solution was 
added, soas to make the volume of fluid in each tube equal to that in the 
corresponding tubes of the other groups. In this group the hemolytic power 
of varying quantities of complement was exhibited. To each of the tubes of 
the second group 0:03 c.c. of sodium chloride solution and 0:03 e.c. of tumour 
