^\ty%si'".""- }  Cincho-^inine.  20  5 
The  solubility  of  the  alkaloid  cinchonia  in  ether  is  given  by  modern 
authorities  as  i  in  about  400  ;  some  older  authorities  give  600,  and  one, 
Bussy  and  Guibourt,  even  830  parts  of  ether.  Calculating  upon  the 
latter  figure  (without  admitting  its  correctness),  the  32  grams  of  ether 
employed  in  each  case  would  have  dissolved  '038  grams  of  cinchonia, 
which  should  be  deducted  from  the,  in  ether,  soluble  alkaloids  ;  the  re- 
maining weight  would  represent  the  correct  total  amount  of  quinia, 
quinidia  and  cinchonidia.  0*038  is  equal  to  i"9  per  cent,  of  2  grams  ; 
the  correct  percentage  of  the  three  alkaloids  named,  would,  according 
to  this  calculation,  be,  for  sample  No.  i,  =  3*00  ;  for  No.  3,  =  2*15, 
and  for  No.  4,  =  3*  10  per  cent.  In,  examining  sample  No.  2,  four 
fluidounces  of  ether  were  used,  which  are  capable  to  dissolve  -089 
grams  of  cinchonia,  and,  if  calculated  for  the  total  amount  of  precip- 
itate and  the  5  grams  of  cincho-quinine,  the  actual  percentage  of  the 
three  alkaloids  named  above  would  be  reduced  to  3'25.  These  cor- 
rected figures  agree  with  the  amount  of  alkaloids  soluble  in  ether  de- 
termined by  Mr.  Wenzell  in  1870,  which  is  2'5  per  cent.  Wenzell 
does  not  give  the  amount  of  ether  employed  by  him,  and  we  are,  there- 
fore, left  to  infer  from  the  above  that  he  may  have  used^  much  smaller 
quantity.  Although  he  failed  to  recognize  the  three  alkaloids,  his  re- 
sults may  be  taken  to  corroborate  those  of  Schefi^er  and  Diehl.  Mr, 
Ebert  has  not  published  the  process  by  which  he  examined  cincho- 
quinine  ;  his  results  cannot  therefore  be  compared  with  the  quantitative 
analyses  referred  to  above. 
While  we  readily  grant  that  the  solubility  of  the  cinchona  alkaloids 
in  ether  is  influenced  by  various  circumstances,  the  investigations  of 
Pasteur,  Van  Heijningen,  De  Vrij,  O.  Hesse,  J.  E.  Howard  and 
others,  prove  that  SchefFer  and  Diehl  have  used  a  much  larger  quantity 
of  this  solvent  than  was  actually  necessary  in  this  case,  and,  as  applied, 
these  tests  cannot  therefere  be  regarded  as  fallacious  zn^  unreliable^  or  the 
quantitative  determinations  to  be  incorrect^  except  in  so  far  as  they  have 
credited  the  samples  of  cincho-quinine  with  a  larger  percentage  of  the  three 
alkaloids  than  is  actually  contained  therein  ;  and  this  is  the  only  light  in 
which  we  can  view  the  assertion  of  the  manufacturers,  that  they  have 
never  sent  out  this  article  constituted  as  determined  by  SchefFer  and 
Diehl.  If,  however,  the  words  "fallacious  and  unreliable"  are  intended 
to  convey  the  idea  that  a  larger  proportion  of  the  salts  of  the  three 
alkaloids  is  used  in  the  manufacture  of  cincho-quinine,  we  can  recon- 
cile this  fact  very  well  with  the  analytical  results  of  the  commercial 
