372         VALUE  OF  VARIOUS  KINDS  OF  CINCHONA  BARK. 
The  presence  of  aldebyd  in  alcohol  ought,  therefore,  to  be  no 
detriment  to  its  use  in  the  preparation  of  chloral.  Nevertheless, 
it  was  found  that  the  product  obtained  from  this  spirit  differed 
in  some  respects  from  the  ordinary  chloral.  Analysis  proved 
that  it  contained  a  distinct  substance. 
It  has  been  shown  that  when  aldehyd  is  subjected  to  the  ac- 
tion of  hydrochloric  acid  gas,  two  molecules  of  it  are  deprived 
of  the  elements  of  water,  and  crotonic  aldehyd  results  : — 
2(C,H,0)  -  H,0  =  CAO. 
The  hydrochloric  acid  resulting  from  the  first  part  of  the  action 
therefore  attacked  the  free  aldehyd,  and  produced  this  change. 
By  the  further  action  of  chloiine  upon  this  crotonic  aldehyd  a 
chlorine  derivative  was  obtained,  having  the  composition  C4H3- 
CI3O.  Whether  this  body  possesses  the  same  medicinal  proper- 
ties as  the  ordinary  chloral  has  not  been  determined. — Pharm. 
Journ.^  Lond.^  May^  1870. 
ESTIMATION  OF  THE  VALUE  OF  THE  VARIOUS  KINDS  01 
CINCHONA  BARK. 
By  Dr.  A.  E.  Vogl. 
Forty  grms.  of  the  previously-pulverized  bark  are  intimately 
mixed  with  ten  grms.  of  quick-lime,  and  made  into  a  thin  paste 
with  water  ;  and  this  mixture  is  dried  (the  temperature  is  not 
stated).  The  dried  mass  is  pulverized,  and  repeatedly  exhausted 
with  boiling  alcohol  at  90  per  cent.  (600  c.c.  are  a  sufficient 
quantity  for  this  purpose)  ;  the  alcoholic  solution  is  filtered,  and 
to  the  filtrate  are  added  about  5  c.c.  of  dilute  sulphuric  acid. 
The  ensuing  precipitate  of  gypsum  having  been  removed  by  fil- 
tration, the  alcoholic  fluid  is  submitted  to  distillation,  and,  after 
having  been  greatly  reduced  in  bulk,  is  further  evaporated  to  a 
very  small  bulk  on  a  water-bath,  whereby  a  flocculent,  resinous, 
vanilla-like  smelling  aromatic  substance  is  precipitated.  After 
this  material  is  again  removed  by  filtration,  to  the  filtrate  is 
added  a  sufficient  quantity  of  a  solution  of  caustic  soda  as  is  re- 
quired for  the  precipitation  of  all  the  alkaloids  contained  in  the 
bark.  These  bodies  are,  by  this  mode  of  treatment,  obtained  in  a 
high  degree  of  purity  in  the  shape  of  a  white  caseous,  or  crystal- 
lino  flocculent  precipitate;  this  should  be  collected  onapreviouslj 
