Am*ju°iy?i89oarm"}  Gleanings  from  the  German  Journals.  345 
solved  0-2  gm.  oxalic  acid.  After  one-half  hour  5-2  gm.  of  a  solution 
of  potassium  carbonate  (1  :  2)  are  added,  thoroughly  mixed  (avoid- 
ing unnecessary  agitation)  and  16-5  gm.  filtered  at  once  through  a  dry 
plaited  filter  of  12  cm.  diameter  into  a  tared  flask  of  30  cc.  capacity. 
To  the  16-5  gm.  filtrate  (representing  1  gm.  opium)  add  5  grams  ether 
free  from  alcohol,  cork  the  flask  and  agitate  briskly  for  10  minutes  ; 
the  ether  is  then  evaporated  by  use  of  a  small  rubber  blast,  the  mor- 
phine collected  on  a  small  plain  filter  and  thoroughly  washed  with 
water  saturated  with  ether,  dried  at  40-500  C,  returned  to  the  flask 
which  has  been  dried  in  the  meantime  and  weighed  to  constant 
weight.  / 
The  addition  of  the  o<alic  acid  is  made  to  precipitate  calcium  salts 
which  are  present  in  all  opium  varieties  excepting  Salonica  opium 
which  gives  no  perceptible  precipitate ;  by  the  use  of  a  large  excess 
of  potassium  carbonate  the  narcotine  is  completely  and  immediately 
precipitated  while  no  morphine  is  precipitated  in  the  minute's  time 
necessary  to  filter  off  the  16-5  gm.  filtrate. 
This  method  has  also  been  applied  to  the  examination  of  extract 
and  tincture  of  opium.  2-5  gm.  extract  are  dissolved  in  water  with 
the  addition  of  o-2  gm.  oxalic  acid,  diluted  to  70  gm.,  5  gm.  solu- 
tion of  potassium  carbonate  added,  15  gm.  filtered  off  (correspond- 
ing to  0-5  gm.  extract),  etc.,  as  above. 
Fifty 'gm.,  with  o  2  gm.  oxalic  acid,  are  evaporated  to  a  thin 
extract  and  gradually  diluted  with  water  to  make  70  gm. ;  to  this 
add  5  gm.  solution  of  potassium  carbonate  and  filter  off  15  gm. 
(corresponding  to  10  gm.  tincture)  and  proceed  as  above. — G.  LoofT, 
Apotheker  Ztg.,  1890,  271. 
Cooling  ointments  are  defined  by  Unna  as  mixtures  of  fat  and 
water  which,  applied  to  the  skin,  produce  a  sensation  of  cold,  owing 
to  the  evaporation  of  the  water.  They  are  to  be  preferred  to  the 
usual  fat  ointments  which  prevent  the  normal  water-evaporation  and 
which  are  often  of  injurious  action.  Lanolin,  owing  to  its  ready 
miscibility  with  water  and  aqueous  solutions,  was  thought  to  be  the 
best  base  for  such  ointments,  but  experiment  did  not  confirm  this ; 
its  effect  is  cooling  at  first,  but  this  quickly  disappears  and  gives 
way  to  a  sensation  of  warmth.  It  was  found  that  mixtures  of 
lanolin  and  fats  mix  with  large  quantities  of  water  and  these  mix- 
tures had  a  permanent  cooling  effect.  The  proportions  of  anhydrous 
lanolin  :  fat  :  water  are  10  :  20  :  30  for  cooling  ointments.  Lanolin- 
