ARTIFICIAL  FORMATION  OF  GLYCERINE.  429 
formed  was  heated  for  eight  days  on  the  oil-hath  to  a  tempera- 
ture of  248p-257°  F.  On  the  conclusion  of  the  reaction,  the 
contents  of  the  flask  were  thrown  upon  a  filter,  and  the  bromide 
of  silver  washed  with  ether. 
The  liquid  was  distilled  until  the  thermometer  marked  284°  F. ; 
the  residue  was  treated  with  lime  and  ether.  The  colorless 
ethereal  solution,  when  evaporated  on  the  water-hath,  left  15-5 
grms.  of  a  neutral  yellowish  oil.  This  was  distilled,  when  a  few 
drops  only  passed  at  482°  F.,  and  the  greater  part  of  the  liquid 
passed  at  532°  F.  The  perfectly  colorless  product  is  neutral, 
possesses  a  slight  odor  of  acetic  acid,  and  is  heavier  than  water? 
at  the  bottom  of  which  it  forms  an  oily  stratum.  When  agitated 
with  a  great  excess  of  water,  it  dissolves.  It  is  soluble  in  all 
proportions  in  alcohol  and  ether.    It  contains — 
Found.  C18H14012. 
C  49-12  49.5 
H  6-60  64 
.  The  formula  C18  H14  O12  is  that  of  triacetine.  The  product 
analysed  really  contained  3  equivs.  of  acetic  acid  and  1  equiv, 
of  glycerine.  0-647  gr.  of  the  artificial  triacetine  were  saponified 
by  baryta-water.  The  liquid  was  freed  from  the  excess  of  baryta 
by  a  current  of  carbonic  acid  and  distillation,  and  precipitated 
by  sulphuric  acid.  0-974  gr.  of  sulphate  of  baryta  was  obtained, 
representing  2-8  or  3  equivs.  of  acetic  acid. 
To  obtain  artificial  glycerine,  triacetine  was  saponified  by 
baryta-water,  and  the  liquid  freed  from  the  excess  of  baryta  was 
evaporated  to  dryness.  The  residue  was  treated  with  absolute 
alcohol  containing  a  small  quantity  of  ether.  The  liquid,  evapo- 
rated in  vacuo.  At  about  392°  F.  a  very  thick  colorless  liquid, 
of  a  distinctly  saccharine  taste,  passed ;  it  was  soluble  in  all  pro- 
portions in  water  and  alcohol,  but  insoluble  in  ether.  This  liquid 
gave  on  analysis  C  38-5,  H  8-6.  The  formula  C6  H8  O6  requires 
C  39-1,  H  8-6.  To  verify  its  identity  with  glycerine,  it  was 
treated  with  iodide  of  phosphorous,  PI2 ;  a  very  brisk  reaction 
took  place,  and  iodized  propylene  was  obtained. 
The  tribromide,  C6  H5  Br3,  fusible  at  61°  F.,  and  boiling  at 
422°  to  423°  F.,  is  not  identical  with  tribromhydrine.  Accord- 
ing to  Berthelot's  experiments,  this  is  a  colorless  liquid,  fuming 
slightly  in  the  air,  and  distilling  at  about  356°  F.    But  if  the 
