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TABLE XVI.—Experiments to ascertain if C. V. serum can neutralise the action
     on citrate plasma in vitro either of cobra venom or of king cobra venom.

     The technique employed was as follows: a fixed quantity, namely, one
milligramme, of each poison, was mixed in small test-tubes with different amounts
of serum. The mixtures were allowed to stand at laboratory temperature for half
an hour. There were then run into each tube 2 c.c. of citrate horse plasma
(1 per cent.). After these mixtures had stood for two hours, 0.4 c.c. of a 2
per cent. solution of calcium chloride was added to each tube. This amount
of lime solution clotted the control in about 25 minutes.

     The results were noted at intervals as follows.

              Citrate plasma 2 c.c.—Cacl2 (2%) :0.4 c c.

     The tube with lime alone clotted solid in 25 minutes.

     From these experiments it is evident that 0.8 c.c. of C. V. serum completely,
and 0.6 c.c nearly, neutralised 1 milligramme of cobra venom: also, that 2 c.c. of
serum failed to neutralise the same amount of king cobra venom. There was,-
however, an attempt at neutralisation in the tubes containing the three greatest
quantities of serum.

TABLE VII.—Experiments to ascertain if C. V. serum can neutralise the
     actions of the venoms of (1) Hoplocephalus curtus, (2) Echis carinata, (3)
     Trimeresurus gramineus, and (4) Crotalus adanzanteus on citrate plasma
     in vitro.

     These four venoms rapidly clot citrate plasma in vitro without the addition
of any soluble salt of lime. The technique employed to test if C. V. serum had
any hindering effect on this action was as follows.