^^sep^'^issr'"'}        Comparison  of  Galenical  Preparations.  443 
The  solution  has  the  density  1-036  U.S.,  M42-1-146  P.  G.,  and  con- 
tains 5  per  cent.,  U.  8.,  15  per  cent.,  P.  G.,  of  potassium  hydroxide. 
Liquor  Potassii  Arsenitis,  U.  8.  Liquor  Kalii  arsenicosi,  P.  G. — 
The  two  preparations  are  identical  in  strength,  100  parts  containing  1 
part  of  arsenious  acid  and  are  flavored  with  compound  tincture  of 
lavender  3  parts,  U.  8.,  with  compound  spirit  of  melissa  15  parts,P  G. 
Liquor  Sodw,  U.  8.  Liquor  Natri  caustici,  P.  G. — The  last-men- 
tioned authority  gives  no  formula  for  preparing  this  solution,  which 
has  the  density  of  1*059  U.  8.,  1'159-1-163,  P.  (x.,and  contains  5  per 
cent.  U.  8.y  15  per  cent.  P.  G.,  of  sodium  hydroxide. 
Liquor  Sodii  8Uioatis,  U.  8.  Liquor  Natrii  silicici,  P.  G. — No  for- 
mula ;  both  liquids  identical. 
Magnesii  Citras  granulatus,  U.  8.  Magnesium  citricum  eflervescens, 
P.  G. — Mix  magnesium  carbonate  11  parts,  citric  acid  33  parts  and 
water  sufficient ;  dry  at  30°C.,  powder  and  mix  intimately  with  sugar 
8  parts,  sodium  bicarbonate  37  parts  and  citric  acid  17  parts;  dampen 
the  fine  powder  with  alcohol  and  convert  it  into  a  coarse  granular 
powder.  U.  8. — Magnesium  carbonate  25  parts,  citric  acid  75  parts, 
and  water  10  parts ;  sodium  carbonate  85  parts,  citric  acid  40  parts, 
sugar  20  parts;  tlie  manipulations  are  identical  and  the  proportions  of 
the  ingredients  very  nearly  so,  with  those  of  the  preceding  formula. 
P.  G. 
Massa  Ferri  Carhonatis,  U.  8.  Pilulse  Ferri  carbonici,  P.  G. — Dis- 
solve ferrous  sulphate  100  parts  in  boiling  water  200  parts  and  add 
syrup  25  parts ;  when  cold  mix  with  a  solution  of  sodium  carbonate 
110  in  water  200  parts;  wash  the  precipitate  with  a  mixture  of  syrup 
1  part  and  water  16  parts,  drain,  express,  mix  with  honey  38  parts  and 
sugar  25  parts,  and  evaporate  the  mixture  to  100  parts.  U.  8.' — Ferrous 
carbonate  is  formed  in  precisely  the  same  manner  as  directed  for  Ferrum 
carbonicum  saccharatum  (see  page  440),  no  sugar  being  used,  the  pro- 
portions being  ferrous  sulphate  50  parts  and  boiling  water  200  parts, 
which  solution  is  filtered  into  a  solution  of  sodium  bicarbonate  in  tepid 
water  500  ])arts ;  the  washed  precipitate  is  mixed  with  sugar  8  parts, 
and  honey  26  parts  and  the  mixture  is  evaporated  to 40  parts;  20  gm. 
of  this  mass  with  sufficient  powdered  marshmallow  root  are  formed  into 
200  pills,  which  are  rolled  in  powdered  cinnamon ;  each  pill  contains 
0-025  gm.  of  iron.    P.  G. 
Mel  despumatum,  U.  8.  Mel  depuratum,  P.  G. — The  latter  autho- 
rity giyes  no  process,  but  requires  this  preparation  to  be  clear,  of  the 
