478  Salicylic  Acid  in  Food  and  Drink.      { AVtober,Pimm' 
The  cry  of  "  salicylic  acid  "  has  so  influenced  the  popular  mind 
that  many  persons  are  under  the  impression  that  the  substance  in 
question  is  an  injurious  product  of  solely  artificial  origin,  and  that 
its  physiological  effect  is  but  slightly  less  injurious  than  that  of 
arsenic  itself.  It  would  no  doubt  surprise  many  of  these  persons  to 
learn  that  an  ordinary  wintergreen  lozenge  contains  as  much  salicylic 
acid  (combined  as  methyl  salicylate)  as  the  average  tumbler  of  jelly 
which  has  been  preserved  with  this  substance  ;  but  such  is  certainly 
the  case,  as  any  one  who  desires  may  verify  for  himself. 
The  presence  of  aniline  colors  and  salicylic  acid  being  most  im- 
portant then,  from  the  standpoint  of  compliance  with  the  food  law, 
more  prosecutions  being  based  on  these  substances  than  on  alt 
others  put  together,  many  persons  feel  entirely  safe  from  prosecution 
when  assured  of  the  absence  of  these  products  from  the  articles 
which  they  are  handling,  and  it  is  the  object  of  this  paper  to  show 
the  retail  druggist  how  he  can  easily  and  effectually  determine  the 
presence  or  absence  of  these  substances  at  least. 
In  looking  for  the  presence  of  aniline  colors  in  articles  of  food  and 
drink,  it  will  be  remembered  that  the  range  of  colors  which  it  is  cus- 
tomary to  use  is  somewhat  limited,  being  confined  principally  to  the 
reds,  yellows  and  browns,  very  few  articles  of  this  nature  being 
colored  either  green  or  blue. 
The  first  step  in  the  operation  of  testing  for  the  presence  of  ani- 
line or  coal-tar  color  is  the  selection  and  preparation  of  some  fat- 
free  woolen  goods.  For  this  purpose  a  good  quality  of  nun's-veiling 
is  obtained  and  freed  from  fat  by  boiling  it,  first  in  a  five  per  cent, 
solution  of  sodium  hydroxide  for  a  few  minutes,  and  then  repeatedly 
in  pure  water  until  the  alkali  has  been  entirely  removed.  This  ma- 
terial is  then  cut  into  strips  of  a  uniform  size  (about  1x2  inches), 
and  preserved  in  a  wide-mouth,  glass-stoppered  bottle  until  it  is  to 
be  used. 
The  material  to  be  tested,  if  a  liquid,  is  to  be  diluted  with  an 
equal  volume  of  water ;  if  it  is  a  solid  or  a  semi-solid  it  is  to  be  dis- 
solved in  about  four  times  its  weight  of  water,  and  the  liquid 
strained  to  remove  particles  of  fruit  pulp  or  cellular  tissue,  which 
would  adhere  to  the  wool  and  interfere  with  the  results.  About  100 
c.c.  (or  4  fluid  ounces)  of  the  liquid  is  placed  into  a  beaker,  4  c.c.  (or 
1  fluid  dram)  of  diluted  hydrochloric  acid  (10  per  cent.)  is  added, 
a  single  strip  of  the  woolen  goods  is  immersed  in  the  liquid  and  the 
