AmNovr;iP8Soarm"}  Gleanings  from  the  German  Journals.  585 
diluted  ammonia  solution  added,  the  flask  corked  and  agitated  thor- 
oughly for  10  minutes.  To  separate  the  emulsion  formed  10  grams 
additional  acetic  ether  are  added,  the  ethereal  layer  carefully  poured 
off,  and  after  addition  of  10  grams  acetic  ether,  the  ethereal  solution 
again  decanted  and  the  contents  of  the  flask  poured  into  a  plain 
filter  of  8  cm.  diameter  ;  the  flask  and  filter  are  twice  was  hed  with 
5  grams  water  saturated  with  acetic  ether,  and  after  allowing  to 
drain,  both  flask  and  filter  are  dried  at  ioo°  C,  the  filter  contents 
transferred  to  the  flask  and  the  latter  dried  to  constant  weight. — E. 
Dieterich,  Pharm.  Centralhalle,  1890,  597. 
Loofs  morphine  estimation  in  opium  (Am.  Journ.  Pha.rm.,  1890) 
has  been  critically  examined  by  E.  Dieterich  ;  the  conclusions  based 
upon  numerous  assays  are  here  given  :  1.  The  use  of  oxalic  acid  is 
unnecessary,  as  the  calcium  salts  present  in  opium  are  not  precipi- 
tated by  potassium  carbonate  until  after  10-12  hours'  standing.  2. 
The  filtration  of  the  precipitated  narcotine  often  proceeds  so  slowly 
that  thrice  the  time  given  by  Loof  is  necessary  to  filter  off  the 
required  quantity;  after  one-half  minute's  standing,  the  morphine 
will  commence  precipitating.  3.  The  precipitation  of  narcotine  is 
not  immediately  complete,  as  stated;  narcotine  contaminating  the 
morphine  obtained.  4.  Potassium  carbonate  has  no  advantages 
over  ammonia  in  precipitating  morphine,  as  this  alkaloid  is  soluble 
in  excess  of  both  precipitants  to  the  same  extent.  5.  By  weighing 
the  morphine  from  only  one  gram  of  opium  any  slight  error  in  the 
estimation  becomes  of  considerable  importance  when  the  results  are 
given  in  percentage. — Pharm.  Centralhalle,  1890,  591. 
Azoimide,  a  new  hydrogen  nitride. — One  of  the  most  interesting 
announcements  in  chemical  research  is  the  discovery  of  an  acid  con- 
taining only  the  two  elements,  hydrogen  and  nitrogen.  The  acid  in 
many  respects  is  analogous  to  the  halogen  acids  ;  it  forms  a  gas  of 
penetrating  odor,  is  easily  soluble  in  water  and  has  a  strong  acid 
reaction;  but  differs  in  having  the  formula  HN3  explained  by  the 
1  N 
structural  formula  H — N     ||    With  ammonia  it  forms  white  fumes 
\  N 
of  NH4N3  or  N4Ht ;  metals  are  rapidly  dissolved  by  it  with  evolution 
of  hydrogen.  The  barium,  mercurous  and  silver  salts,  BaN(5,  Hg.,Nt. 
and  AgN6  respectively,  have  been  prepared  ;  the  last  two  are  very 
explosive.    The  acid  is  obtained  by  a  series  of  organic  reactions 
