488 
Laboratory  Notes. 
(  Am.  Jour.  Pharm, 
\      Oct.,  1877. 
opinion  being  based  upon  the  effects  of  the  use  of  sugars  as  food,  these 
effects  being  stated  chiefly  for  persons  of  weak  or  deranged  digestion. 
He  surmises,  from  testimony  and  report  as  to  sugar  manufacture,  that 
sugar  of  lead  is  much  used  in  decoloring  sugars,  and  that  traces  of  the 
lead  escape  being  removed.  Beside  the  lead,  he  claims  no  information 
as  to  what  the  asserted  injurious  constituents  are,  but  seems  to  assume 
that  they  are  inorganic,  from  manufacturers'  chemicals.  There  appears 
to  be  a  general  popular  distrust  of  the  syrups  of  grocers'  trade,  with  an 
impression  that  some  of  them  contain  dangerous  inorganic  constituents, 
left  behind  from  the  use  of  chemicals  in  their  manufacture. 
Fourteen  samples — ten  sugars  and  four  syrups,  all  selected  by  Mr. 
Rossiter,  were  subjected  to  an  analysis  embracing  the  following  inquiries : 
1.  Special  qualitative  examination  for  lead,  by  a  method  of  known 
degree  of  accuracy. 
2.  Special  qualitative  examination  for  arsenic,  with  a  determination  of 
the  least  quantity  revealed  by  the  process  employed. 
3.  Quantitative  determination  of  the  total  ash,  and  a  full  qualitative 
determination  of  its  constituents,  with  particular  care  in  looking  for  tin 
and  zinc. 
4.  Determination  of  the  glucose  (laevulose  and  dextrose). 
5.  Determination  of  the  water  in  obtaining  a  constant  weight  in  an 
air-bath,  at  about  o,o°C.  The  sugars  had  been  previously  air-dried  by 
standing  in  papers  in  a  dry  place. 
6.  Determination  of  the  specific  gravity  of  the  syrups. 
A  quest  was  made  for  arsenic,  because  it  might  be  left  from  the 
sulphuric  acid  of  starch-sugar  manufacture,  from  the  sulphurous  acid 
used  to  remove  lead  when  lead  acetate  is  employed  in  bleaching,  and 
possibly  from  other  chemicals  or  even  from  zinc  or  tin  apparatus. 
All  the  analyses  were  performed  by  Messrs.  J.  S.  Johnson  and  S. 
E.  Parkill. 
1.  The  examination  for  lead  was  made  simply  by  treating  a  solution 
of  the  sugar  with  hydrosulphuric  acid  gas  ;  this  test  being  more  delicate 
than  a  test  after  removing  the  organic  matter  by  any  means.  One 
hundred  grams  of  the  sugar  or  syrup  were  dissolved  in  .a  sufficient 
quantity  of  water  and  treated  with  the  gas  for  several  hours.  In 
working  with  10  grains  of  the  solution,  Wormley  ("  Michrochemistry 
of  Poisons,"  p.  361)  found  that  a  solution  containing  one-250,oooth  of 
lead  oxide  gave  a  faint  brownish  tint;  containing  one-ioo,oooth,  a 
