254 
American  Pharmacopoeia. 
Am.  Jour.  Pharm. 
June,  1906. 
and  in  how  far  the  limits  of  value  given  in  the  Pharmacopoeia  agree 
vyith  those  obtained  at  1 50.  We  have  here  in  several  cases  found 
more  or  less  considerable  differences.  For  the  purpose  of  a  better 
review,  we  have  combined  the  results  obtained  in  a  tabulated  form 
(p.  256).  The  limits  of  value  given  in  the  American  Pharmacopoeia, 
which  do  not  agree  with  ours,  are  printed  in  italic  type.  These 
limits  printed  thus  cannot  and  should  not  in  our  opinion  be  accepted 
as  such,  for  they  are  inconsistent  with  the  values  fixed  for  150,  and 
are  consequently  incorrect.  Differences  of  1  in  the  third  decimal 
figure  have  been  left  out  of  account,  as  they  lie  within  the  limits  of 
error.    We  would  still  mention  that  the  differences  between  the 
1  c°  2K0 
specific  gravities  determined  at  ~0  and  at  — Q,  as  given  by  us,  agree 
15  25 
well  on  the  whole  with  those  ascertained  previously  by  Schreiner 
and  Downer,1  and  also  that  the  average  value  of  these  differences  is 
the  same  as  that  found  by  those  authors,  viz.  0-00064  per  degree  of 
temperature. 
Of  alcohols,  the  American  Pharmacopoeia  recognizes  a  strong 
alcohol  of  94-9  per  cent,  by  volume  (Alcohol),  and  a  weak  one  of 
48-9  per  cent,  by  volume  (Alcohol  dilutum).  In  the  following  pages 
the  former  is  designated  simply  as  "  alcohol." 
Anise  Oil  (Oleum  amsi). — Colorless  or  faintly  yellow  ;  d25Q  0  975 
to  0-985  ;2  aD250_2o3;  solidifying  point  not  below -f-  150;  soluble  in 
an  equal  volume  alcohol  and  in  5  vol.  90  per  cent,  alcohol. 
Benzaldehyde  (Benzaldehydum). — Colorless  liquid,  strongly  re- 
fractive, with  at  least  85  per  cent,  pure  benzaldehyde;4  d250  about 
1-045;  aD±o°;  boiling  point  179  to  1800;  soluble  in  alcohol  in 
every  proportion ;  test  for  absence  of  chlorinated  products. 
Bitter  Almond  Oil  (Oleum  amygdala  amarce). — Colorless  or  yel- 
low ;  content  of  benzaldehyde  at  least  85  per  cent.;5  content  of  hydro- 
1  Pilar.  Archives  4  (1901),  165.    Report  April,  1902,  80. 
2  The  upper  limit  of  value  should  be  0*988,  as  otherwise  especially  the  oils 
richest  in  anethol,  and  consequently  the  most  valuable  anise  oils,  could  not  be 
used.    Comp.  also  the  table  (p.  256). 
3  This  should  read  :  up  to  —  20. 
4  According  to  the  method  of  determination  by  means  of  neutral  sodium 
sulphite  indicated  by  the  Pharmacopoeia,  we  found  it  impossible  to  obtain  even 
approximately  satisfactory  results  ;  for  this  reason,  we  greatly  doubt  the  use- 
fulness of  this  method. 
5  Comp.  note  under  benzaldehyde. 
