AmAu°g'if92arm'}  Immunity  and  Cure.  427 
tion  is  subcutaneous  or  intravenous.  With  the  blood  serum  of 
these  rabbits  thus  rendered  insusceptible,  Klemperer  succeeded  in 
curing  septicaemia  in  mice. 
In  mice  the  course  of  the  disease  (septicaemia  Koch)  is  character- 
istic. A  mouse  has  an  injection  of  o-i  ccm.  of  the  fresh  bouillon- 
culture.  Within  24  hours  there  are,  as  a  rule,  no  signs  of  illness, 
but  on  the  morning  of  the  second  day  there  is  a  great  change. 
The  creature  sits  cowered  in  a  heap  with  its  eyes  plastered  to.  As 
the  disease  progresses  it  curls  itself  up  more  and  more,  and  finally 
dies  in  this  position  in  the  course  of  the  third  day.  By  injecting 
0-5- 1 -o  ccm.  of  the  blood  serum  of  a  rabbit  rendered  insusceptible, 
Klemperer  managed  to  avert  the  disease  altogether,  and  this  was 
the  case  whether  the  injection  of  the  serum  was  24  hours  in  advance 
or  injected  at  the  same  time  as  the  bacillus  culture.  But — and  this 
is  of  more  importance — a  cure  resulted  in  every  case  when  the 
blood  serum  was  introduced  24  hours  after  infection,  and  in  three 
cases  48  hours  after  infection.  In  these  last  three  cases  the  mice 
had  already  assumed  the  characteristic  posture,  and  the  control 
mice  died  in  a  few  hours.  The  affected  recovered  but  slowly  after 
the  serum  injection,  and  it  was  some  time  before  they  became  lively 
and  lost  their  curved  attitude. 
The  efficacy  of  this  serum  was  tried  on  other  germ  diseases,  but 
in  every  case  the  result  was  negative.  It  was  found  also  that  mice 
cured  by  the  serum  were  proof  against  later  infection  by  mouse 
septicaemia  bacilli.  How  long  the  period  of  immunity  may  last 
Klemperer  cannot,  as  yet,  say.  Injections  on  the  eighth  and  four- 
teenth day  were  negative. 
Klemperer  repeated  a  similar  set  of  experiments  with  Fried- 
lander's  pneumonia  bacillus  with  precisely  similar  results. 
He  also  experimented  with  the  bacillus  pyocyaneus,  and  with 
similar  success.  Here,  also,  as  in  the  two  other  diseases,  he  found 
that  the  blood  serum  of  an  animal  rendered  insusceptible  could  cure 
that  one  disease  only,  being  absolutely  useless  when  employed  against 
any  other  germ. 
These  are  Klemperer's  facts — we  now  come  to  his  conclusions. 
In  the  wonderful  transmission  of  immunity  lies  the  kernel  of  the 
matter. 
The  blood  serum  does  not  destroy  the  bacillus,  either  the  mouse 
septicaemia  bacillus  or  Friedlander's.    A  few  bacteria  in  5  ccm. 
