Am.  jour.^Pharm.|  Quinine  and  Homoquinine.  519 
and  taken  up  with  ether,  which  quickly  deposits  the  alkaloid  in  crystals. 
This  operation  is  repeated  as  often  as  may  be  necessary,  but  generally 
a  second  recrystallization  of  the  base  in  this  way  suffices  to  separate 
any  admixture  of  quinine. 
On  a  previous  occasion,1  I  had,  upon  the  basis  of  the  results  of 
analyses  I  and  II,  which  were  before  me  at  the  time,  represented 
homoquinine  by  the  formula  C19H22N202.  But  in  the  course  of  this 
investigation  it  has  given  weighty  evidence  in  favor  of  the  formula 
C20  H24  N2  02,  with  which,  moreover,  analysis  IV,  made  by  me  only 
recently  with  well  crystallized  material,  corresponds  very  well.  Before 
analysis  the  substance  was  dried  at  120°  to  125°  C. ;  it  then  gave: 
I.  0-2154  gram  0-5820  C02  and  0*1420  H20 
II.  0-2436  gram  0-6535  CO,  and  0-1555  H20 
III.  0-2453  gram  0-6660  CO,  and  0-1585  H20 
IV.  0-2613  gram  0-7095  C02  and  0'1765  H20 
Calculated  for  Found. 
CigHsoNoOa  Co0H24N2O2  I.  II.  III.  IV. 
C.  73-54  .  .  .  74~*07~  .  .  .  73*73  7316  74*04  74*05 
H.      7*09     .    .    .       7*41    .    .    .    7*35        7*09        7*17  7*50 
From  ether  containing  water  homoquinine  separates,  if  undisturbed, 
partly  in  concentrically  grouped  needles,  partly  in  stout  decided  prisms, 
derived  from  the  rhombic  system,  terminating  at  the  ends  in  a  dome, 
the  crystals  being  sometimes  isolated  and  sometimes  a  few  concentrically 
aggregated  together.  In  a  disturbed  crystallization,  on  the  other  hand, 
according  to  the  degree  of  concentration  of  the  solution,  either  a  sandy 
powder  or  a  crystallization  consisting  of  delicate  lamella?  is  obtained. 
In  all  cases  it  contains  water  of  crystallization,  the  quantity  varying 
between  2  and  2J  molecules,  a  part  of  which  is  readily  given  off  at  80° 
to  100°  C,  and  the  remainder  first  at  120°  to  125°  C. 
I.  0  2438  gram  gave  at  120°  to  125°  C.  0*0234  H.,0 
II.  0*2784  gram  gave  at  120°  to  125°  C.  0-0303  H20 
III.  0*2500  gram  gave  at  120°  to  125°  C.  0*0260  H,0 
IV.  0*2733  gram  gave  at  120°  to  125°  C.  0*0273  H90 
V.  0-2935  gram  gave  at  120°  to  125°  C.  0*0322  H,0 
VI.  0-6085  gram  gave  at  120°  to  125°  C.  0*0710  H,0 
Calculated  for 
Co0H,4N2O2  +2H.,0    Co0Ho4NoOo +2^H.,0 
H,0     .    .    ."   10*0     .    .    .  "12*19 
Found 
I.  II.        III.        IV.        V.  VI. 
11-65       10-88       10*40       10  00       10*97  11*66 
1  Beriehte,  xv,  857  ;  Am.  Jour.  Phar.,  1882,  364. 
