'75 
detennining  factor,  especially  in  attacks  i,  2,  3,  0,  7,  ii,  12,  13,  14 
and  14a,  This  relationship  is  exhibited  in  tabular  form  in  Table  50 
(p.  247),  and  is  further  considered  in  Section  V,  pp.  130-165. 
The  duration  of  the  attack  of  haemoglobinuria  was  usually  short, 
lasting  from  three  or  four  hours  to  four  days.  (Table  50).  Relapses 
occurred  in  three  cases  (4,  8  and  10).  In  the  first  two  a  single  relapse 
occurred  respectively  ten  days  and  two  days  after  the  original  attack  ; 
in  the  last  case  a  remarkable  series  of  small  relapses,  about  fifteen  in 
number,  occurred  during  the  ten  days  following  the  original  attack, 
and  bore  no  obvious  relation  to  the  quinine  taken  during  this  period 
(Table  50).  Three  of  the  patients  (6,  7  and  14)  suffered  from  another 
attack  of  blackwater  fever  after  the  lapse  of  a  period  varying  from 
two  to  three  and  a  half  months. 
The  severity  of  the  constitutional  symptoms  varied  considerably 
in  different  attacks,  being  insignificant,  for  example,  in  Case  7,  while 
severe  collapse  lasting  about  twenty  hours  occurred  in  Case  2. 
Vomiting  was  severe  in  attacks  3,  6a,  9,  14a,  16  and  17.  Pain  in  the 
back  was  common,  but  was  not  severe.  Rigors  occurred  at  the  onset 
of  the  attack  in  Cases  i,  2,  3,  5,  8,  9,  10,  12,  14  and  14a.  Cramps  in 
the  calf  muscles  were  severe  in  Case  2.  Illness  of  several  days’ 
duration  preceded  the  attack  of  blackwater,  except  in  i,  4,  13  and  14a. 
The  complications  observed  were  hyperpyrexia  (Case  13), 
suppression  of  urine  (Cases  7a  and  ii)  and  vomiting  attended  with 
extreme  weakness  (Case  16).  All  these  complications  terminated  in 
death. 
The  blood  obtained  by  pricking  the  finger  tip  was  generally 
remarkably  watery  in  aspect.  TIaemoglobinaemia  was  usually 
present  during  haemoglobinuria  in  the  cases  in  which  this  point  was 
investigated  (3,  7a,  10,  14,  15  and  17,  cp.  Table  34,  p.  75),  the  highest 
amount  observed  being'  0‘95  per  cent.  Methaemoglobin  was  also 
observed  in  relatively  small  amount  during  blackwater  in  most  cases 
in  the  blood  plasma,  which  was  dark  orange  in  colour  in  every  attack, 
except  5,  6a  and  9,  in  which  it  was  light  yellow  (Cases  t  and  13  were 
not  examined) 
The  reaction  of  the  red  blood  cells  to  quinine  in  vitro  was  noted 
in  Cases  3,  4,  5,  7,  7a,  8,  10,  1 1,  14,  14a  and  15  ;  it  was  found  not  to 
exhibit  any  marked  alteration  (Table  24,  p.  46). 
