558 
U.  S.  Pharmacopoeial  Revision. 
Am.  Jour.  Pharm. 
August,  1920, 
Dissolve  the  sodium  hydroxide  in  loo  Mils  of  water  and  filter 
.  the  solution  through  asbestos.  Weigh  the  oleic  acid  in  a  tared  vessel, 
add  the  cresol,  and  stir  thoroughly.  Now  add  the  solution  of  sodium 
hydroxide,  stir  vigorously  until  saponification  occurs,  and  finally 
add  sufficient  water  to  make  the  solution  weigh  looo  Gms. 
Liquor  Ferri  Chloridi. — ^This  solution  is  described  as  "reddish 
brown"  in  color.    It  is  more  nearly  "yellowish  brown." 
Liquor  Ferri  Tersulphatis. — The  description  here  is  "yellowish 
brown."  It  should  be  "reddish  brown."  The  color  descriptions 
of  these  two  solutions  were  evidently  confused. 
Liquor  Formaldehydi. — Methyl  alcohol  is  specified  in  this  solu- 
tion, to  prevent  polymerization.  It  would  be  desirable  to  permit 
the  use  of  either  methyl  or  ethyl  alcohol. 
Liquor  Magnesii  Citratis. — The  use  of  talc  in  this  solution  is 
unnecessary  and  undesirable.  Partial  sterilization  of  the  product, 
as  directed  in  the  present  Pharmacopoeia,  is  unnecessary  when  the 
solution  is  sold  within  a  few  days,  and  only  adds  to  the  time  neces- 
sary for  its  preparation.  If  the  solution  is  to  be  kept  for  any  length 
of  time,  it  should  then  be  properly  sterilized.  This  can  best  be 
accomplished  by  heating  the  completed  solution  in  stoppered  bottles 
in  an  Arnold  sterilizer,  or  steam  boiler. 
Liquor  Plumhi  Suhacetatis. — This  preparation  may  be  made 
equally  satisfactory  by  mixing  the  lead  oxide  with  the  solution  of 
lead  acetate,  agitating  occasionally  during  seven  days  and  filtering. 
Heating  for  one  hour  evaporates  the  solution  continuously,  neces- 
sitating the  addition  of  more  water  and  usually  causing  considerable 
precipitation  of  lead  as  carbonate.  The  cold  maceration  method 
has  been  used  for  a  number  of  years  in  large  laboratories  and  also 
on  a  small  scale  and  the  resulting  product  frequently  tested  and  found 
to  be  identical  with  that  prepared  by  the  hot  process. 
Magma  Magnesiae. — The  suggestion  of  Sister  Bertha  Mueller 
(This  Journal,  p.  162,  1920),  that  this  magma  be  made  by  triturating 
commercial  light  magnesium  oxide  with  lime  water,  has  been  found 
an  improvement  over  the  present  official  method  and  should  be 
carefully  tested  for  possible  U.  S.  P.  use.  The  minute  quantity 
of  calcium  present  is  not  objectionable  and  all  washing  of  the  magma- 
is  avoided.    The  formula  is  as  follows: 
Light  Magnesium  Oxide,  U.  S.  P   60  Gms. 
Solution  of  Calcium  Hydroxide,  U.  S.  P.,  sufficient  to 
make 
1000  Mils 
