quinine  bihyclrochloride  is  0'8t  per  cent.,  complete  haemolysis  was  not 
attained  after  the  lapse  of  three  hours,  while  in  Table  3,  with  a 
concentration  of  the  quinine  salt  of  0’635  per  cent,  haemolysis  vvas 
complete  in  three  hours,  the  ratio  of  the  weight  of  red  blood  cells  to 
that  of  quinine  bihydrochloride  being,  in  the  first  case,  about  43  to  i, 
and,  in  the  .second  case,  36'4.  to  i. 
2.  Ac/ ion  of  quinine  in  /he  form  of  alkaloid  on 
red  blood  cells. 
So  far  the  action  upon  red  blood  cells  of  quinine  in  the  form  of  a 
salt  has  been  investigated.  Since  quinine  has  not,  however,  been 
shown  to  be  present  in  the  blood  in  the  form  of  a  quinine  salt,  but 
may  possibly  be  present  in  the  free  state,  it  was  therefore  decided  to 
investigate  the  action  of  quinine  in  the  alkaloidal  form  (Table  5). 
These  experiments,  owing  to  the  sparing  .solubility  of  alkaloidal 
quinine,  namely  one  in  about  sixteen  hundred  parts  of  water  at  15°  C., 
could  only  be  carried  out  in  very  dilute  solution.  The  series  of 
experiments  given  m  Table  5  is  similar  to  those  given  in  Table  I, 
except  that  the  free  alkaloid  is  employed  instead  of  the  quinine  salt. 
Here  it  is  seen  that  the  amount  of  haemolysis  is  less  than  when  the 
quinine  salt  was  employed,  the  transition  point,  which  as  before  is 
sharply  marked,  occurring  with  a  concentration  of  alkaloid  of  0-063 
per  cent.,  which  is  equivalent  to  O’oy;  per  cent,  of  quinine  bihydro¬ 
chloride,  while  the  weight  of  red  blood  cells  completely  haemolysed  is 
six  and  a  half  times  that  of  the  free  quinine  employed,  or  five  and  a 
quarter  times  that  of  the  corresponding  amount  of  quinine  bihydro¬ 
chloride. 
Table  5.  Haemolysis  of  red  blood  cells  by  quinine  in  alkaloidal  state.  Duration  of 
experiment  three  hours.  Temperature  37®  C. 
No.  of 
Experi¬ 
ment 
CoMPOSiTioK  OF  Mixture  of 
Rtu  Bi.ood 
C'f.lls  and  Quinine  Solution. 
Quinine  (alkaloid)  0*078 
Weight  of  wet  red  blood  cells  4-8 
W'eight  of  quinine  (alkaloid)  1 
0*063  ^*11 
6*4 
j 
0-052  “1,  0-045% 
8-0  q'6 
I  1  I 
o-ojg  0;, 
1  r*l 
i 
I 
Complete 
Complete 
Partial  Partial 
Trace 
2 
Complete 
Complete 
Partial  Slieht 
Trace 
3 
Complete 
Complete 
Partial  P.artial 
P.irtial 
4 
Complete 
Complete 
Marked  Marked 
'Prace 
5 
Complete 
Marked 
Marked  Partial 
Partial 
