HJEMOLYTIC SERUM 327 



instead, and although the following method is directed 

 to the preparation of human haemolysin the same 

 procedure serves in all cases. 



THE PREPARATION OF H^MOLYTIC SERUM. 



Apparatus Required: 



Small centrifuge, preferably electrically driven, with two recep- 

 tacles for tubes, and enclosed in a safety shield (Fig. 162). 



Sterile centrifuge tubes (10 c.c. capacity), Fig. 163. 



FIG. 162. Small electrical centrifuge. 



Sterile pipettes (10 c.c. graduated) in case. 



Sterile glass capsules (in case). ^^ 



Sterile test-tubes. ^ugliube' 



Sterile all glass syringe (5 c.c. or 10 c.c. capa- 

 city) and needle. 

 Reagents Required: 



Normal saline solution. 



10 per cent, sodium citrate solution in normal saline. 



Human blood (vide infra}. 



METHOD. 



1 . Select a healthy full-grown rabbit of not less than 

 2500 grammes weight in accordance with the directions 

 already given (page 322) and prepare it for intraperi- 

 toneal inoculation. 



2. Measure out 2 c.c. citrated human blood (collected 

 at a surgical operation or a venesection, or withdrawn 

 by venipuncture from the median basilic or median 

 cephalic vein of a normal adult) into a centrifuge tube 

 and centrifugalise thoroughly. 



