812 
Supplement  to  the  “ Tropical  A{/ric}iUaridT 
r\lAY  I,  1S07. 
manner  did  not  contract  rinderpest  as  a result  from 
the  inoculation,  there  can  he  doubt  that  even  the 
glycerine  exercised  a destructive  effect  upon  the 
rinderpest  virus,  a circumstance  which  is  tlie  more 
remarkable  as  almost  all  infective  materials,  parti- 
cularly the  small-pox  lymjdi,  are  not  destroyed  by 
it,  but  even  preserved.  After  a sufficiently  long  time 
had  elapsed  I injected  virulent  rinderpest  blood, 
and  this  second  inoculation  produced,  after  the 
usual  period  of  incubation,  genuine  landerpest. 
The  phenol-cow,  however,  remained  healthy,  and  it 
is  not  impossible  that  the  first  injection  had  a pro- 
tective influence.  I therefore  repeated  thise.xperi- 
ment,  and  hope  soon  to  be  able  to  report  to  you 
on  the  result.  Being  aware  that  distilled  water 
destroj’s  the  red  and  white  blood  corpuscles,  and 
thinking  that  it  may  possilily  also  injure  the 
rinderpest  contagion,  I diluted  rinderpest  blood 
with  tills  liquid  in  a proportion  of  1'20,  and  inocu- 
lated one  beast  with  tliis  material.  The  animal 
thus  operated  uponshoa  ed  tlie  first  symjitoms  of 
rinderpest  later  than  usual,  but  the  course  of  the 
disease  was  just  as  violent  and  its  termination 
fatal.  In  order  to  find  bow  far  the  dilution  of  the 
blood  can  be  carried  without  damaging  its  in- 
fective qualities,  1 diluted  fresh  rinderpest  blood 
with  the  .so-called  physiological  ClNa  solution  (0‘6 
per  cent.)  in  a proportion  of  I'oOO,  and  injected  one 
cubic  centimetre  of  this  mixture.  In  spite  of  the 
extremely  small  quantity  of  infective  material, 
which  the  animal  received  subcutaneously,  viz., 
1‘600  c.cm.  of  blood,  it  contracted  rinderpest  after 
exactly  the  same  time,  and  manife.sted  the  same 
malignant  symptoms  as  those  animals  which  had 
received  10  c.cm.,  a dose  5,000  times  larger. 
A most  noteworthy  experiment  was  the  follow- 
ing : — 1 dried  10  c.cm.  blood  by  the  moderate  tem- 
perature of  31  deg.  C.  during  a period  of  four  days, 
and  after  having  dissolved  it  again  in  water  I in- 
oculated one  head  of  cattle.  This  beast  remained 
perfect  ly  healthy,  and  I may  therefore  sa  fely  ex- 
press the  opinion  that  ilesicciition,  even  during 
such  a short  space  of  time,  render^  the  rinderpe.^t 
virus  non-effective.  This  is  highly  important  for 
the  farming  community,  and  1 intend,  therefore, 
making  similar  exp(?riinents  with  other  media, 
particularly  the  skin  and  the  f;cces,  in  order  to 
ascertain  tlie  influence  which  desiccation  has  upon 
them.  I have  already  .stated  that  blood,  dried  and 
dissolved  again  in  the  above-mentioned  manner, 
did  not  produce  any  ill-effect  upon  the  animal  in- 
oculated, and  have  now  to  add  it  also  had  no  p-o- 
tective  action,  for  the  beast  contracted  rimlerpest 
readily,  when  I subsequently  inoculated  it  with 
fresh  blood.  Of  all  the  animals  which  as  yet  have 
been  suffering  fi'om  rinderpest  on  the  e.xperimental 
station,  four  have  recovered. 
In  my  previous  report  I have  already  mentioned 
that  they  would  serve  for  immunising  experiments, 
but  I thought  it  first  necessary  to  convince  my- 
self if  these  animals  were  really  perfectly  safe 
again.^t  now  infections.  I therefore  inoculated 
with  rinderpe.st  blood  two  “salted  ” animals  and 
at  the  same  time  a fresh  one.  The  result  was,  that 
the  latter  died  of  rinderpest,  whilst  the  other  two 
never  evinced  the  least  symptoms  of  the  disease, 
not  even  the  slightest  rise  of  temperature.  Having 
thus  proved  the  thorough  immunity  of  these  ani- 
mals, I drew  from  the  stronger  one  a large  quantity 
of  blood  and  inoculated  one  beast  with  100  c.cm, 
serum.  After  this  animal,  which  on  the  next  day 
was  inoculated  hypodermically  with  1'5  c em  of 
rinderpest  blood,  bad  remained  well  for  six  diys, 
it  was  re-inoculated  with  a largerquantity  of  virus  , 
viz.,  1 cc.m.  of  rinderpest  blond.  Another  anim  il 
was  vaccinated  with  a mixture  of  both  ieium  and 
blood,  which  previous  to  the  operation  was  kept 
for  one  night  in  the  ice-chest.  This  a;iim  il  like- 
wise did  not  show  anything  ami.ss  during  the  next 
six  days  and  was  then  on  the  seventh  day  in- 
oculated with  a large  quantity  of  rinderpest  blood 
Both  these  animals  withstoocl  even  the  .•second  in 
oculation  without  any  injurious  result.  These  ex- 
periments clearly  demonstrate  that  the  .serum  of 
immune  animals  po.ssesses  a certain  protective 
power,  but  before  having  made  further  exj»eri- 
meuts  it  is  not  possible  for  me  to  say  for  how  long 
a period  this  immunity  will  last  and  if  thi.s  method 
can  be  carried  out  m ])r(Lvi.  I have  tried  to  com- 
municate rinderpest  to  other  animals  than  rumi- 
nants on  a somewhat  extensive  scahq  but  have  not 
found  any  other  species  of  which  1 could  with 
certainty  expre.ss  the  opinion  that  they  are  liable 
to  the  jiesfe. 
With  reference  to  birds  I may  state  without  any 
hesitation  that  they  are  not  susceptible.  We  have 
experimented  on  fowls,  doves,  pigeons,  guinea 
fowls,  and  a crane,  but  with  negative  results.  An 
eagle  and  a seci'etary  bird  I have  fed  for  weeks  on 
intestines  taken  only  from  ritiderpest  animals,  but 
I have  not  observed  the  slightest  ill-effect  upon 
either  of  them.  Dogs  proved  themselves  perfectly 
immune.  I also  did  not  succeed  in  giving  the 
pest  to  donkeys.  Rodents,  such  as  mice,  guinea- 
pigs,  rabbit.s.  are  also  not  susceptible.  In  pigs 
only  it  .seems  as  if  it  were  po.ssible  to  transmit  in- 
fective material  successfully,  but  our  e.xperiments 
in  this  re.spect  are  as  yet  not  complete. 
The  arrangements  on  the  experimental  station 
have  proved  themselves  to  be  perfect,  for  we  had 
no  case  of  spontaneous  infection  since  reporting  to 
you  last. 
Another  vi.<it  to  several  rinderpest  farms  in  the 
Free  State,  and  a small  and  quickly  checked  out- 
break of  rinderpest  in  a suburb  of  Kimberley  af- 
forded me  again  a sjileuili  I opjKirtunity  of  making 
further  observations  ami  of  procuring  new  material 
for  inoculation  and  examination. — 
DR.  Koch's  fouktii  rkport. 
I have  the  honour  to  report  herewith  several 
important  facta  resulting  from  my  investigations 
on  the  Rinderpest  Fxperimental  .Station. 
In  my  last  report  1 was  already  in  a position  to 
inform  you  that  blood  serum  of  cattle  which  had 
already  recovered  from  rinderpest  had  a certain 
immunising  effect  upon  the  healty  stock  when  in- 
oculated with  it. 
Its  protective  properties,  however,  are  not  very 
great,  for  100  c.cm.  of  such  serum  are  reejuired 
to  protect  an  animal  against  an  inoculation  with 
a small  dose  of  rindeipest  blood.  This  immunity 
is  in  its  nature  merely  a “j),a.ssive"  one,  and  will 
only  last  during  a short  j)eriod. 
For  protective  inoculation  on  a large  scale  such 
serum  is  not  apiilicable,  but  I succeeded  in  im- 
munising within  a fortnight  several  animals  by 
means  of  a mixture  of  serum  and  vindent  rinder- 
pestblood  tosucha  degree  that  they  were  enabledto 
withstand  an  injection  of  L>()  ccm.  rinderpest  blood, 
a ten  thousandth  part  of  which  is  a fatal  dose. 
From  this  fact  1 judge  that  the  immunity  of 
