Am.  Jour.  Pharm.  > 
Oct.,  1878.  J 
New  Test  for  Glycerin. 
485 
aside  to  cool  and  subside,  after  which  the  clear  alcoholic  solution  con- 
taining the  glycerin  was  decanted  into  another  dish.  The  solution  was 
evaporated  to  dryness  as  before,  and  again  exhausted  with  absolute 
alcohol.  The  solution  from  this  second  treatment  with  alcohol  was 
evaporated  nearly  to  dryness,  and  a  few  drops  of  water  added.  The 
solution  thus  obtained  was  made  faintly  alkaline  to  delicate  litmus 
paper  with  dilute  soda  solution,  and  tested  in  the  manner  already 
describe^.  In  each  case  the  color  was  distinct,  of  course  most  decided 
in  the  case  of  the  residue  from  the  5  per  cent,  solution.  A  solution 
containing  onequarter  of  1  per  cent,  was  examined  in  the  same  way, 
and  gave  the  color  distinctly.  Beer,  to  which  was  added  only  one- 
tenth  of  1  per  cent,  of  glycerin  was  examined  by  first  concentrating 
and  shaking  with  petroleum  ether,  to  remove  hop  resin,  and  then 
evaporating  to  dryness  and  treating  as  above.  In  this  case  green  color, 
though  less  intense  than  before,  was  distinctly  seen.  Several  experi- 
ments were  made  with  beers  to  which  glycerin  was  not  added  ;  but 
treating  them  in  the  way  described  no  green  color  could  be  obtained. 
It  was  noticed  that  the  consistence  of  the  residues  from  beers  to  which 
glycerin  had  been  added,  compared  with  the  residues  of  beers  contain- 
ing no  glycerin,  was  very  different.  The  former  were,  of  course, 
moist  and  syrupy,  while  the  latter  were  much  harder  and  even 
brittle. 
Glycerin  in  Wine. — To  some  sherry  wine  was  added  I  per  cent,  of 
glycerin.  Of  this  solution  50  cc.  were  evaporated  to  dryness  over 
a  water-bath.  The  residue  was  treated,  as  previously  described,  with 
25  cc.  of  absolute  alcohol.  The  alcohol  solution  was  then  evaporated 
over  a  water-bath  nearly  to  dryness,  and  a  few  drops  of  water  added. 
This  solution,  made  faintly  alkaline  and  tested,  gave  the  green  flame 
distinctly.  The  same  wine  without  glycerin  gave  no  green  color  to 
flame. 
Glycerin  in  Milk. — 100  cc.  of  milk,  to  which  1  per  cent,  of  glycerin 
was  added,  were  evaporated  to  dryness  over  a  water-bath.  The 
residue  was  treated  with  50  cc.  absolute  alcohol,  and  the  alcoholic 
solution  so  obtained  evaporated  to  dryness  as  before.  A  few  drops  of 
water  were  added,  and  the  mixture  filtered  through  a  moistened  filter 
to  separate  fat.  The  filtrate  was  then  rendered  alkaline  and  tested. 
The  green  color  was  distinctly  observed.     100  cc.  of  milk  without 
