THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
JUNE,  1885. 
NOTE  ON  FROZEN  GLYCERIN.^ 
By  Wallace  Procter,  Ph.G. 
Having  occasion  to  empty  a  50  lb.  case  of  glycerin,  daring  the  early 
part  of  April,  I  found,  to  my  surprise,  that  half  the  contents  of  the 
can  was  a  mass  which,  on  examination,  seemed  to  possess  a  crystalline 
structure  of  great  toughness  and  solidity.  Suspecting  an  adulteration, 
tests  for  glucose,  as  the  most  probable,  were  first  applied,  but  with  a 
negative  indication. 
On  applying  to  the  party  from  whom  the  glycerin  was  purchased,  I 
was  informed  that  the  whole  of  a  large  consignment,  received  from 
abroad,  was  more  or  less  "  frozen,"  as  it  is  expressed  technically.  The 
stateuient  was  also  made  that,  in  the  course  of  twenty  years'  extensive 
dealing  in  glycerin,  only  once  previously  had  it  been  observed  in  this 
condition,  and  that  some  three  years  ago.  It  was  of  the  nitro  grade, 
such  as  is  used  in  the  manufacture  of  nitroglycerin,  and  almost  with- 
out water.  The  article  in  question  was  not  sold  as  the  finest  quality, 
but  as  a  second  grade,  though  comparing  favorably  in  appearance  and 
freedom  from  odor  with  any  usually  to  be  procured. 
A  further  and  more  critical  examination  was  made,  with  the  follow- 
ing results —specific  gravity  of  unfrozen  portion,  at  15*5°C.,  1'235  to 
1-237. 
A  portion,  heated  to  100°C.  for  ten  minutes  with  an  equal  volume 
of  sulphuric  acid,  gave  but  a  very  slight  coloration ;  warmed  with 
diluted  sulphuric  acid,  an  appreciable  but  very  faint  butyric  odor  was 
developed;  when  diluted  with  distilled  water,  test  solution  of  silver 
nitrate  produced  no  cloudiness  after  standing  some  hours.  As  before 
stated,  the  absence  of  sugars  was  also  determined. 
These  results  seemed  to  conclusively  prove  that  the  phenomenon 
was  inherent  with  the  glycerin  itself,  and  not  caused  by  any  admixture 
or  inipurity. 
1  Read  at  the  Pharmaceutical  Meeting,  held  May  10th,  1885. 
18 
