Am.  Jour.  Pharm. 
June,  1888. 
Laboratory  Notes. 
277 
LABORATORY  XOTES. 
Abstracts  from  Theses. 
Commercial  sugar  lohitened  by  blue  pigment  appears  to  be  more  fre- 
quently met  with  at  the  present  time  than  formerly.  During  the  spring 
and  summer  of  1887,  Charles  C.  Stratton,  Ph.  G.,  procured  at  different 
times  17  samples  of  sugar,  all  of  which  were  labeled  first  grade  gran- 
ulated/^ the  majority  of  the  samples  being  the  products  of  one  refinery. 
Ever}^  one  of  these  sugars  was  whitened  with  a  blue  pigment,  the  nature 
of  which  was  not  examined  except  in  a  few  instances,  when  it  proved 
to  be  ultramarin.  For  determining  the  amount  of  blue  pigment,  six 
pounds  of  sugar  were  used  of  each  lot,  except  a  few  specially  noted  be- 
low. The  sugar  was  dissolved  in  pure  water;  the  syrup  was  set  aside 
for  3  or  4  weeks,  and  then  decanted  from  the  sediment;  the  residue 
was  diluted  with  water,  mixed  with  alcohol,  and  this  mixture  allowed 
to  settle,  decanted  and  filtered,  the  undissolved  portion  being  washed 
upon  the  filter,  dried  and  weighed.  The  yield  of  blue  pigment  was  as 
follows:  1.,  2  grains;  2.,  8  grains;  3.,  10  grains;  4.,  6  grains  (mostly 
dirt;  little  blue);  5.,  6  grains;  6.,  5  grains  (about  one  half  dirt);  7., 
(from  25  oz.)  IJ  gr.;  8.,  6  gr.;  9.,  (from  25  oz.)  f  gr.;  10.,  3  gr.;  11., 
4  gr.;  12.,  12J  gr,,  of  which  about  4  gr.  was  blue  pigment;  13.,  5J  gr. 
blue  and  5  gr.  dirt;  14.,  very  little  blue;  15.,  12J  gr.  nearly  pure 
blue;  largest  amount  observed;  16.,  3 J  gr.,  and  17.,  3  gr.  blue  and  2 
gr.  dirt.  Since  most  of  the  samples  came  from  one  factory,  it  will  be 
seen  that  the  coloring  matter  used  for  different  lots  of  sugar  by  the 
same  maker  varies  in  amount,  but  is  in  all  cases  small  and  probably 
not  injurious,  though  it  should  be  considered  as  an  adulterant. 
Reference  is  also  made  by  the  author  to  a  paper  published  in  a  west- 
ern journal,  stating  that  the  sugars  of  five  refineries  in  Xew  York  and 
Philadelphia,  were  found  to  be  whitened  with  ultramarin  in  three 
cases,  and  with  Prussian  blue  in  two  cases,  while  the  sugar  of  a  Brook- 
lyn refinery  had  been  found  free  from  foreign  coloring  matter. 
Assay  of  chocolates. — Howard  M.  Smith,  Ph.  G.,  examined  five 
samples  of  commercial  chocolate  by  the  following  process :  The  choco- 
late, using  5  gm.  of  each  sample,  was  exhausted  by  maceration  with 
petroleum  spirit,  and  the  liquid  filtered  off  and  evaporated  spontan- 
eously. The  residue  after  driving  off  the  petroleum  with  heat,  was 
mixed  with  an  equal  weight  of  magnesium  oxide,  macerated  for  two 
days  with  50  cc.  of  80  per  cent,  alcohol,  the  mixture  heated  to  boil- 
ing, and  the  liquid  filtered  into  a  tared  beaker  and  evaporated  to  dry- 
