GLEANINGS  FROM  GERMAN  JOURNALS. 
21 
produce  a  splendid  blue  color.    Nitrous  acid  and  nitrites  cause 
the  same  coloration  as  nitric  acid.    Ihid.  570-571. 
An  improved  apparatus  for  the  suhUmation  of  benzoic  acid 
has  been  constructed  by  C.  Rump.  It  consists  of  a  circular 
kettle  made  of  sheet  iron,  18  inches  in  diameter,  12  inches  high, 
which  is  placed  upon  a  good  stove  and  has  a  cover,  through  the 
centre  of  which  a  thermometer  can  be  inserted.  At  two  oppo- 
site sides  the  kettle  connects  with  a  6'  inch  tube  6  inches  in 
length,  and  these  are  inserted  into  tubes  3  inches  long,  fastened 
into  the  paper  boxes  44  inches  in  length  and  27  inches  wide,  at 
the  extreme  end  of  which  a  hole  of  4  inches  diameter  is  cut 
into  the  lid  and  supplied  with  a  tube  one  foot  long.  The  benzoin 
or  benzoic  acid  is  put  into  an  iron  or  earthen  ware  capsule,  which 
is  placed  into  the  sheet-iron  kettle.  The  opening  in  the  cover 
allows  the  feeding  of  the  apparatus  after  sublimation  ceases. 
The  cover  may  be  kept  heated  to  prevent  condensation  of  the 
acid,  which  sublimes  very  regularly  if  the  thermometer  is  kept 
at  a  temperature  of  200  to  240°  C.  No  luting  is  required. 
Ibid,  671-674. 
Potato  fusel  oil  contains,  according  to  Dr.  Hugo  Trommsdorff, 
propylic  alcohol ;  besides  this,  two  alcohols  appear  to  be  present 
in  it,  boiling  respectively  below  90°  C.  and  between  101  and 
103°  C.    Ibid.  688,  689. 
Assay  of  Opium. — Dr.  Schneider  proposes  for  the  sixth 
edition  of  the  Austrian  Pharmacopoeia  tte  following  assays  : 
1.  10  grammes  dried  and  powdered  opium  are  exhausted 
with  altogether  150  grm.  water,  acidulated  with  20  grm.  muria- 
tic acid,  sp.  gr.  1*12  ;  the  dried  residue  must  not  weigh  over  4*5 
grm.  The  liquid,  after  dissolving  in  it  20  grm.  table  salt,  is  set 
aside,  and  after  24  hours  filtered.  The  filtrate  is  precipitated  , 
with  ammonia,  the  crystals  collected  after  24  hours,  redissolved 
in  acetic  acid  and  precipitated  with  ammonia.  The  precipitate, 
after  washing  and  drying,  must  weigh  not  less  than  one  gramme. 
2.  10  grm.  dry  powdered  opium  are  macerated  for  24  hours 
with  50  grm.  water,  and  exhausted  by  percolation  in  a  funnel 
with  100  grm.  more  water.  The  liquid  is  boiled  for  10  minutes 
with  10  grm.  lime,  filtered  and  the  residue  washed  with  a  little 
