^^^aIai^sjs.''"''  }  Selections  from  Danish  A  r  chives  for  Pharmacy .  171 
point  and  stoppered  with  cotton-wool.  If  not  all  the  contents  of  a 
bottle  have  to  be  used  at  once,  then  the  cotton  plug  has  to  be  replaced 
by  a  cork,  through  which  passes,  first,  a  short  tube  (the  nethermost  end 
of  which  is  drawn  out  to  a  point),  filled  loosely  with  cotton-wool ;  and, 
then,  a  syphon,  the  long  end  of  which  is  furnished  with  a  gum-elastic 
tube  and  spring-compressor.  This  arrangement  is,  of  course,  to  be 
applied  before  heating.  As  the  liquid  is  drawn  off,  the  air  filters  through 
the  cotton. 
The  bottles  have  to  be  rinsed  with  boiling  water,  since  cold  water 
contains  germs,  on  the  presence  of  which  fermentation  and  putrefac- 
tion depend. 
Compressed  Powders. 
Prof.  Rosenthal  (Berlin,  Prussia)  recommends  to  compress  bulky 
powders  which  have  to  be  taken  in  large  doses  ;  for  instance,  Kousso, 
and  other  worm  medicines. 
He  does  this  by  means  of  a  common  press  (vertical),  the  lower  cross- 
piece  of  which  is  provided  with  a  hole,  which  can  be  covered  by  a 
plate.  A  tube  is  put  on  top  of  said  plate,  and  the  several  doses  of 
the  powder  are  introduced,  separated  by  small  metal  cylinders.  Strong 
pressure  is  now  applied,  the  above-mentioned  plate  is  removed,  and 
the  compressed  powder  tablets  fall  through  the  hole  in  the  cross-piece. 
It  will  be  seen  that,  since  no  water  or  other  constituent  is  used,  said 
tablets  must  dissolve  readily  in  the  stomach.  The  largest  convenient 
size  to  swallow  will  be  found  to  be  1—2  grams.* — [Berliner  Klin, 
Woch  enschrft^  1874.) 
Nitrous  Oxide  (Laughing  Gas). 
A  circular  of  the  Royal  Danish  Board  of  Health  (June,  1873)  P^*^" 
vides,  that  :  ist.  Nitrous  oxide  gas  must  be  dispensed  from  pharmacies 
only,  on  requisition  (prescription)  of  an  authorized  physician  or  dentist. 
2d.  The  reservoir  must  be  sealed  and  labelled  :  "  Nitrous  oxide  gas." 
It  does  not  expect  every  apothecary  to  prepare  said  gas,  but  requires 
the  manufacturers  to  see,  that  :  ist.  The  nitrate  of  ammonia  does  not 
contain  chlorine,  sulphuric  acid  nor  nitrate  of  potassa.  2d.  That  the 
nitrous  oxide  gas  passes  through  water,  a  solution  of  protosulphate  of 
iron  and  a  solution  of  potassa  or  soda.  3d.  The  gas  must  not  be  dis- 
pensed, unless  it  has  been  in  contact  with  water  for  at  least  24  hours. 
*  One  or  two  Philadelphia  firms  make  compressed  pills  a  specialty. 
