558 
Glyceraie  of  Sucrate  of  Lime,  etc. 
f  Am.  Jour.  Pharm  . 
\     Dec.  1,  1873. 
of  sucrate  of  lime.  This,  in  a  certain  state  of  dilution,  he  uses  to 
prepare  his  new  chalk  liniment* 
Solubility  of  Sucrate  of  Lime  in  Grlycerin. — Sucrate  of  lime  is 
very  soluble  in  glycerin  and  the  addition  of  water  and  heat  hastens 
the  solution.  The  temperature  may  be  raised  to  the  boiling  point 
without  fear  of  the  coagulation  of  the  monobasic  sucrate  of  lime, 
which  is  prevented  by  the  glycerin.  The  following  two  experiments 
had  for  their  object  to  compare  the  solubility  of  sucrate  of  lime  in 
water  and  in  glycerin,  separately  : — 
(a)  Fifty  grams  of  dry  sucrate  of  lime,  in  fine  powder,  were  treated 
with  100  grams  of  distilled  water,  at  from  75°  to  80°  C,  the  liquor 
filtered,  and  the  proportion  of  lime  determined  by  an  alkalimetric 
operation.  Ten  grams  of  the  solution  gave  0*4958  gram  of  lime  cor- 
responding to  3*646  grams  of  sucrate  of  lime.  The  solution  was 
coagulated  by  heat. 
(b)  One  hundred  grams  of  dry  sucrate  of  lime,  in  fine  powder,  were 
treated  with  a  mixture  of  equal  portions  of  water  and  glycerin  (100 
grams  of  each),  at  a  temperature  of  75  C,  and  the  liquor  filtered. 
The  filtration  was  slow.  An  alkalimetric  estimation  showed  that  10 
grams  of  liquor  contained  0*5161  gram  of  lime,  corresponding  to  3*756 
grams  of  dry  sucrate  of  lime.  In  this  case  heat  did  not  cause  the 
monobasic  sucrate  of  lime  to  coagulate. 
In  comparing  these  results  it  must  be  admitted  that  the  solubility 
of  sucrate  of  lime  is  nearly  equal  in  water  and  in  glycerin.  The 
slight  difference  is  due  to  a  peculiarity  that  is  worth  mentioning. 
During  the  evaporation  of  the  sucrate  of  lime  to  obtain  that  com- 
pound in  a  dry  state  there  is  formed  a  small  quantity  of  carbonate  of 
lime.  If  the  sucrate  be  treated  with  water  traces  only  of  the  carbon- 
ate formed  go  into  the  solution,  whilst  in  the  mixture  of  water  and 
glycerin  the  whole  is  dissolved.  In  fact,  if  a  few  drops  of  hydro- 
chloric acid  be  added  to  each  of  the  solutions  there  is  a  notable  disen- 
gagement of  carbonic  acid  from  the  glycerate,  but  only  a  very  feeble 
one  from  the  aqueous  solution.  This  would  explain  the  slight  differ- 
ence in  the  two  experiments. 
Saturated  Glycerate  of  Sucrate  of  Lime. — Without  having  recourse 
to  the  use  of  dry  sucrate  of  lime,  and  in  order  to  shorten  the  opera- 
tion, a  nearly  saturated  solution  of  sucrate  of  lime  may  be  obtained 
by  adopting  the  following  formula  : — 
Slaked  Lime,    .    200  grams. 
