384 Mr. J. Henderson-Smith. Increase in the [Mar. 26, 



cc. c.c. 



To 0*02 unheated immune serum, \ hr. after bleeding, must be added 0*225 normal serum. 



?» » *■ 5> }) 0*2 „ 



», )) •* „ „ 0'225 „ 



3| „ „ 0-25 



5? 55 6 „ „ 0'25 „ 



0*02 c.c. unheated serum by itself, no perceptible lysis. 



Since 0*25 c.c. normal serum was required, when the immune serum had 

 been heated, there was contained in the dose of the unheated immune 

 serum — 



c.c. c.c. c.c. 



Of the £ hr. sample complement equivalent to 0*25 — 0*225 = 0*025 of the normal serum. 

 ■*■ j) » )j 0*0o „ j, 



55 55 51 0*025 ,, „ 



)} 



55 



3) 



55 



53 



35 



» 



55 



„ 3f „ „ „ No appreciable amount. 



53 " 55 



The amount of complement increased to double the amount by the end of 

 the first hour, but had decreased again after two hours, and by four hours had 

 become inappreciable. 



Example 6. — Immune serum from rabbit injected with ox corpuscles ; of 

 this when heated 0*05 c.c. required 0*13 c.c. normal rabbit serum. To 0*05 of 



the immune serum unheated — 



c.c 

 From the I hr. sample must be added 0*1 normal serum. 

 1 „ „ 0*085 



1* 5, 5, o*08 



33 " 55 53 ^ * 55 



33 " 3? 31 O'l „ 



C.C. 



Therefore the dose of the £ hr. serum contained the equivalent of 0*03 normal serum. 



„ 53 1 35 53 0*045 „ 



33 55 I? 53 55 0*05 „ 



55 55 3 „ „ 0*03 „ 



53 55 5 „ „ 03 „ 



The complement increased by about 66 per cent, in l£ hours. 



By this method we can demonstrate the occurrence of change in the 

 quantity of complement contained in the immune serum, and can determine 

 the time during which such change is occurring. It is true that we 

 supplement an " immune " complement ■ by a " normal " complement ; and it 

 is probable that partial complements do not exist in the same proportions in 

 the two sera. It is even possible that they are not identical, even when 

 derived from animals of the same species, although there is no evidence of 

 this, and such evidence as we have is against this view. Even if it were so„ 

 however, the fact would not invalidate the method, in so far as it indicates 

 the occurrence of change and the duration of that change. The amount of 



