ADeim\rerPS6m-}      Solution  of  Hydrogen  Peroxide.  583 
for  nitrobenzol  by  reducing  and  testing  for  aniline,  positive  results 
were  obtained. 
Correspondence  with  the  firms  making  the  article  in  question 
revealed  the  interesting  fact  that  the  reaction  which  had  been  entirely 
ascribed  to  the  presence  of  nitrobenzol,  was  due,  in  part  at  least,  to 
the  presence  of  acetanilide  which  had  been  used  as  a  preservative 
agent  in  preventing  the  deterioration  of  the  solution  with  the  accom- 
panying loss  of  oxygen. 
Further  investigation  of  the  facts  in  the  case  showed  that  the 
practice  was  confined  to  a  few  manufacturers  who  had  regarded  it 
in  the  light  of  a  trade  secret  until  the  approach  of  the  period  of  the 
enforcement  of  the  regulations  of  the  Food  and  Drugs  Act,  which 
requires  the  labeling  of  all  products  containing  acetanilide,  made  this 
condition  no  longer  possible. 
That  the  presence  of  small  quantities  of  acetanilide  does  preserve 
the  solution  from  decomposition  was  shown  by  the  fact  that  several 
samples  examined  which  were  known  to  be  at  least  four  months  old 
showed  from  9.5  to  10.5  volumes  of  oxygen.  These  had  originally 
been  supposed  to  contain  10  volumes. 
There  would  probably  be  no  objection  to  the  use  of  small  quanti- 
ties of  acetanilide  when  the  advantages  of  increased  stability  are  con- 
sidered, but  the  product  should  be  labeled,  as  it  will  have  to  be  after 
January  1,  1907,  with  the  amount  of  the  preservative  stated  on  the 
label. 
The  most  interesting  fact  in  connection  with  the  investigation  of 
the  subject  is  the  production  of  the  nitrobenzol-like  odor  referred  to 
in  the  first  part  of  this  article.  It  requires  about  four  months  for 
the  development  of  this  odor,  which  is  very  pronounced  and  very 
characteristic. 
The  presence  of  acetanilide  in  the  freshly  made  and  odorless  prod- 
uct can  be  detected  by  shaking  out  about  25  c.c.  of  the  solution  with 
a  few  cubic,  centimeters  of  chloroform,  evaporating  the  latter  to  dry- 
ness and  applying  the  isonitrile-test  for  the  presence  of  acetanilide. 
