146       Recent  Literature  Relating  to  Pharmacy.  {AmMirch,i9oi.rm' 
The  percentage  of  alkaloids  in  young  succirubra  leaves  is  ten 
times  greater  than  that  of  the  old  leaves,  but  the  actual  amount  in 
each  leaf  is  not  as  great.  The  average  tree,  having  10,000  leaves 
weighing  about  5  kilos  when  dried  and  yielding  about  ^  per  cent, 
alkaloids  a  day,  produces  about  2  kilos  of  alkaloids  a  year  (5 
grammes  a  day),  a  quantity  much  greater  than  that  obtained  each 
year  from  the  bark  of  an  average  tree.  This  shows  the  leaves  fully 
capable  of  producing  all  the  alkaloids  we  find.  The  excess  in  for- 
mation is  easily  accounted  for:  (1)  The  leaves  are  never  com- 
pletely emptied  each  day.  (2)  The  unfavorable  weather  reduces 
alkaloidal  output. 
The  theory  of  leaf  formation  of  alkaloids  is  strengthened  by  the 
facts  that  the  petioles  are  richer  in  alkaloids  than  the  blade,  that 
the  branch  bark  contains  more  than  the  trunk  bark,  that  the  root 
bark  is  practically  free  from  alkaloids.  The  leaves,  however,  con- 
tain no  crystalline  alkaloids,  hence  no  quinine.  This  is  explained 
by  saying  that  the  leaves  produce  a  fundamental  and  soluble  alka- 
loidal base,  which  is  elaborated  into  the  true  alkaloids  when  being 
stored  in  the  bark. — Bet.  dtsch.  Ph.  Ges.,  1900,  124. 
H.  V.  A. 
ASSAY  OF  VOLATILE  OIL  IN  AROMATICS. 
Distil  an  alcoholic  percolate  of  the  drug  with  steam,  taking  care 
that  distillate  represents  an  aliquot  part  of  the  drug.  Place  100  c.c.. 
of  this  distillate,  to  which  a  few  drops  of  diluted  sulphuric  acid  is 
added,  and  which  must  not  contain  more  than  50  per  cent,  of  alco- 
hol, in  a  special  flask,  having  a  lower  bulb  of  95  c.c.  capacity 
connected  by  a  narrow  neck,  graduated  from  98  c.c.  to  100  c.c.  in 
fractions  of  05  c.c,  to  a  second  bulb  holding  25  c.c.  up  to  its  neck, 
which  in  turn  connects  with  a  third  bulb  of  value  in  agitation.  The 
liquid  in  the  flask  is  cooled  in  water  to  exactly  200  C.  and  an  exact 
reading  is  taken,  after  which  petroleum  ether  (sp.gr.  0  640  to  067  o)> 
of  same  temperature  is  added  up  to  the  125  c.c.  mark.  In  this 
way  the  flask  contains  two  distinct  layers  of  liquid,  say  the  aqueous 
up  to  100  c.c.  and  the  benzin  up  to  125  c.c.  The  mixture  is 
vigorously  shaken  five  minutes  and  then  allowed  to  cool  to  200  C, 
when  it  is  noticed  that  the  oil  formerly  present  in  the  aqueous  layer 
has  been  absorbed  by  the  benzin,  increasing  volume  of  the  latter 
the  amount  of  oil  present,  as  proven  by  experiments  of  the  author. 
— Dr.  Neuman  Wender,  Ph.  Post,  1900,  344.  H.  V.  A. 
