REVIEW  OF  PHARMACOPCEIA  HELVETICA. 
533 
Emplast.  hydrargyri. — Mercury  3,  turpentine  1,  lead  plaster 
8,  wax  2. 
Emplast.  oxycroceum. — Wax  32,  resin  32,  powdered  saffron 
1,  annatto  1,  galbanuni  4,  ammoniacum  27  myrrh  2,  turpen- 
tine 8. 
Emplast.  resinosum. — Wax  2,  suet  2,  Burgundy  pitch  3,  tur- 
pentine 4,  resin  8. 
Emplast.  saponatum. — Lead  plaster  24,  white  lead  16,  soap  8, 
camphor  1,  dissolved  in  1  benne  oil. 
Emulsio  amygdalarum  is  rather  nicer  than  our  Mistura  amyg- 
dala ;  it  is  made  of  almonds  1,  sugar  1,  water  sufficient  to  ob- 
tain 12. 
Emulsio  oleosa  consists  of  oil  of  almonds  4,  mucilage  6,  water  32. 
There  are  57  extracts  officinal  in  the  Swiss  pharmacopoeia,  of 
which  number  2  are  oleoresins,  (cubebs  and  male  fern),  16  are 
made  with  hot  or  boiling  water,  7  with  cold  water,  23  with  alco- 
hol, and  2  only  are  inspissated  juices.  Hot  water  is  used  chiefly 
for  bitter  herbs,  like  wormwood,  blessed  thistle,  centaury,  &c. 
Quassia  and  rhatany  yield  a  better  extract,  though  not  quite  as 
much,  if  treated  with  cold  water  as  directed  by  our  pharmaco- 
poeia. It  is  strange  that  so  many  European  pharmacopoeias 
direct  Extractum  taraxaci  to  be  made  from  the  recently  collected 
root  and  leaves,  either  by  boiling  or  digesting  it  with  water, 
while  in  this  case  it  is  more  necessary  than  in  many  others  to 
avoid  the  long  continued  application  of  heat. 
The  extracts  of  aloes,  myrrh,  cinchona  (frigide  paratum),  gen- 
tian, liquorice,  opium  and  rhubarb  are  made  with  cold  water ; 
the  two  first  and  two  last  are  very  properly  evaporated  to  dry- 
ness. 
The  pharmacopoeia  prepares  the  narcotic  extracts  by  exhaust- 
ing the  recently  powdered  leaves  with  alcohol  of  -890  ;  after  the 
alcohol  has  been  distilled  off,  the  residue  in  the  retort  is  allowed 
to  rest  in  a  cool  place,  the  clear  liquid  is  decanted  and  filtered 
from  the  separated  chlorophyl  and  evaporated.  These  extracts 
are  necessarily  stronger  than  the  alcoholic  extracts  of  our  phar- 
macopoeia which  contain  all  the  chlorophyl  taken  up  by  the  al- 
cohol. Extractum  aconiti,  belladonna,  conii,  digitalis,  hyoscy- 
ami,  lacturse  virosse  and  strammonii  are  made  in  this  way,  the 
