194 



G. G. Heslop 



the tubes was then brought to a common level by the addition 

 of 0.9 per cent, saline solution, so that eaeh tube contained 2.5 

 c.c. of fluid. One unit of sensitised red blood cells (sheep) was 

 then added to each tube, and, after shaking, the tubes were placed 

 in the incubator at 37°C. Results were read at the end of half 

 an hour, one hour, and two hours' incubation respectively, and, 

 of the tubes showing complete haemolysis, the one containing 

 the smallest amount of complement was noted. From the table 

 set out below it will be seen that this tube was tube 6, which 

 contained 0.25 c.c. of complement dilution; that amount being 

 the minimum quantity required to completely haemolyse one 

 unit of sensitised red blood cells in one hour at 37°C. Even 

 after two hours' incubation it was found that no tube lower than 

 lube 6 in the series showed complete haemolysis. 



Parallel with series A, series B was set up. The quantities 

 of sensitised red blood cells and complement dilution were exactly 

 the same as those used in the corresponding tubes in series A, 

 imt to each tube in series B (excepting where indicated in the 

 controls), 0.15 c.c. of a 1 in 10 dilution of inactivated bovine 

 serum was added. The tubes were filled to a common level with 

 saline solution, as in series A, and placed in the incubator at 

 37°C, the results being read after half an hour, one hour, and 

 two hours' incubation. Each series was thoroughly controlled, 

 as shown in the following tables : — 



Series A. 



Tube 



Comple- 

 ment, 

 1 in 10 



Saline 

 0.9% 



Sensitised 

 R.B.C. 5% 



Decree of Haemolysis after 



incubation for 



Half hoffr 



One hour 



Two bours 



1 



- 5 - 



20 



- 5 - 



Complete - 



Complete 



- Complete 



2 



- 45 - 



205 



- '-5 - 



„ 



,, 



>> 



3 



- 4 - 



21 



- 5 - 



,, 



„ 



„ 



4 



•- 35 - 



2- 15 



•5 - 



>> 



,, 



„ 



5 



- 3 - 



22 



- 5 - 



„ 



„ 



, f 



6 



- 25 - 



225 



•5 



Almost 

 complete 



Complete 



- Complete 



7 ' 



- -2 - 



23 



•5 



Partial 



Partial 



- Not 



complete 



9 



- 15 - 



235 



•5 



Very 



slight 



Slight 



- Slight 



9 



- -1 - 



24 



- 5 - 



None r 



Very 

 slight 



- Slight 



10 



- -05 - 



245 



'5 



None 



None 



- None 



11 



— - 



25 



- 5 - 



None 



None 



- None 



