27 
sodium  hydrate  employed,  which  are  well  m  the  nighbourhood  of  the 
lowest  concentration  of  quinine  bihydrochloride,  the  weight  of  red 
blood  cells  completely  haemolysed  per  unit  weight  of  the  haemolytic 
agent  is  also  ajiproximately  proportional  to  the  square  root  of  the 
latter.  Thus  m  the  case  of  hydrochloric  acid  the  maximum  weight 
of  wet  red  blood  cells  completely  haemolysed  in  three  hours  m 
concentrations  of  o'ooi  14  per  cent,  and  o'ooqi  per  cent,  respectively  is 
182  and  91,  the  calculated  amounts  being  1 53  and  gi.  Similarly  with 
concentiations  of  sodium  hydrate  of  0'0i  57  per  cent.,  o'oogo  per  cent, 
and  0-0045  per  cent,  the  maximum  weights  of  red  blood  cells  com¬ 
pletely  haemolysed  in  three  hours  at  37°  C.  were  resjrectively  166,  133 
and  1 13,  per  unit  weight  of  the  haemolytic  agent,  the  calculated 
amounts  being  163,  136  and  113.  In  the  case  of  quinine  in  the  free 
state,  although  here,  in  consequence  of  the  sparing  solubility  of  the 
alkaloid  and  the  limited  range  of  concentration  available,  it  has  not 
been  possible  to  determine  this  point  with  sufficient  accuracy  to  enable 
an  altogether  satisfactory  proof  of  the  relationship  between  con- 
centiation  and  haemolytic  power  to  be  given,  the  concentrations 
employed  being  somewhat  close  together  and  the  experimental  error 
relatively  large  in  consequence,  yet  the  figures  obtained— 6-4  and  4-8 
for  the  red  cells  and  0-0628  per  cent,  and  0-0366  per  cent,  for  the 
concentration—  indicate  that  the  former  is  proportional  to  the  square 
root  of  the  latter,  the  calculated  amounts  for  the  red  cells  being  5-8 
and  4'8  respectively. 
6.  Na/ure  of  ilu  action  of  quinine  in  the  alkaloidnl  state  on 
red  blood  cells. 
When  haemoglobin  is  set  free  the  action  of  the  haemolytic  agent 
is  not  duected  to  the  red  cell  as  a  whole,  for  the  cell  is  not  chemically 
homogeneous,  but  to  one  of  its  constituents.  Whether  this  constituent 
IS  haemoglobin  itself  or  is  part  of  the  stroma,  as  in  the  case  of 
haemolysins  produced  as  antibodies  by  the  injection  of  red  cells  into  a 
foreign  organism,*  is  not  determined  by  our  further  experiments, 
which  have  instead  been  directed  to  the  problem,  what  is  the  nature 
of  the  action  of  the  haemolytic  agents  which  have  been  used  in  the 
*  Ivar  Bang  mid  J.  Forssinaii,  Untersuchungen  iiber  die  H!imoly.sinbi]dmig.  Zeitschr 
1.  d.  ges.  Biochemie,  1906.  Bd.  -Vtll,  .S.  238.  "  ® 
