556 
SOLVENT  POWERS  OF  GLYCERIN". 
THE  SOLVENT  POWERS  OF  GLYCERIN. 
By  John  S.  Blockey, 
Some  time  back,  having  occasion  to  experiment  with  the  di- 
sulphate  of  quinine,  I  accidentally  discovered  that  glycerin,  if 
gently  heated,  will  dissolve  more  than  8  grs.  per  fluid  drachm, 
or  about  one-twelfth  of  its  weight  of  this  salt ;  this  fact  will 
render  glycerin  a  valuable  vehicle  for  the  therapeutical  adminis- 
tration of  quinine,  as  I  noticed  in  a  communication  to  the  "Lan- 
cet "  a  few  weeks  ago.  I  have  since  found  that  glycerin  ap- 
pears to  possess  properties  that  may,  perhaps,  give  it  a  place 
among  the  usual  dissolving  substances  ;  for  instance,  salicin 
soluble  in  22  parts  by  weight  of  cold  water,  and  in  30  parts  of 
80  per  cent,  alcohol,  will  dissolve  in  8  parts  of  cold  glycerin ; 
santonin  soluble  in  250  parts  of  boiling  water,  and  in  3  of 
boiling  alcohol,  will  dissolve  in  18  parts  of  boiling  glycerin  ; 
the  solution,  however,  becomes  thick  and  almost  solid,  with  only 
one  grain  of  santonin  in  36  of  glycerin  on  cooling,  and  a  satu- 
rated boiling  solution  of  santonin  in  glycerin,  when  cold  may 
be  inverted  without  loss. 
Strychnia  is  soluble  in  80  parts  of  boiling  glycerin,  but  very 
slightly  in  cold. 
From  these  experiments  it  appears  that  many  substances  are 
soluble  in  glycerin,  in  a  very  different  ratio  to  their  solubility 
in  water,  &c.  Iodide  of  lead  dissolves  sufficiently  in  boiling  gly- 
cerin, to  cause  the  solution  to  become  turbid  on  cooling.  Aconi- 
tina  is  scarcely  soluble  at  all  in  this  medium.  May  not  glycerin 
be  found  a  solvent  for  many  other  comparatively  insoluble  sub- 
stances, both  in  the  inorganic  and  in  the  organic  kingdom  ? 
I  invariably  heat  the  glycerin  to  give  it  greater  fluidity,  and 
the  quantity  that  may  be  thus  dissolved,  the  solution  remaining 
clear  on  cooling,  I  estimate  as  the  quantity  soluble  in  cold  gly- 
cerin.— London  Chemist,  September,  1857. 
PREPARATION  OP  IODIDE  OF  BARIUM  FROM  WXTHERITE. 
By  C.  R.  C.  Tichbokne. 
As  iodide  of  barium  is  used  in  photography,  and  as  iodide  of 
aluminium  (another  salt  proposed  as  an  iodizer)  may  be  made 
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