no  The  Detection  of  Methyl  Alcohol.  {AVaXf9holrm* 
addition  the  alkaline  phloroglucinol  test  reagent  does  not  keep  as 
satisfactorily  as  the  resorcinol  solution,  so  that  for  the  official  test  to 
be  used  in  the  forthcoming  Pharmacopoeia  they  have  recommended 
the  following.  They  believe  that  this  can  be  carried  out  with  uniform 
results  by  any  careful  experimenter,  and  it  is  relatively  simple  in  its 
experimental  details,  as  compared,  for  instance,  with  either  the 
Riche  and  Bardy  or  even  the  Rimini  test. 
U.  S.  Pharmacopoeia  Methyl  Alcohol  Test. — Into  a  test-tube  of 
about  40  c.c,  I  c.c.  of  the  alcohol  or  spirit  to  be  tested  should  be 
poured,  and,  if  it  be  undiluted,  enough  distilled  water  added  to  make 
the  liquid  measure  10  c.c.  If  the  alcohol  be  already  diluted,  a  cor- 
respondingly larger  volume  of  it  should  be  taken  and  diluted  to 
10  c.c,  so  that  the  proportion  of  alcohol  in  the  liquid  shall  not  be 
more  than  about  10  per  cent,  by  volume.  A  copper  wire  spiral 
(made  by  winding  1  meter  of  No.  18  clean  copper  wire  closely 
around  a  glass  rod  7  mm.  thick,  making  a  coil  about  3  cm.  long, 
the  end  of  the  wire  being  formed  into  a  handle)  should  be  heated 
to  redness  in  a  flame  free  from  soot,  and  plunged  steadily  quite  to 
the  bottom  of  the  liquid  in  the  test-tube  and  held  there  for  a  second 
or  two,  then  withdrawn  and  dipped  into  water  to  cool.  This  treat- 
ment with  red-hot  copper  should  be  repeated  five  or  six  times,  im- 
mersing the  test-tube  in  cold  water  to  keep  down  the  temperature 
of  the  liquid.  The  contents  of  the  test-tube  should  now  be  filtered 
into  a  wide  test-tube  and  boiled  very  gently.  If  the  odor  of  acetal- 
dehyde  be  perceptible,  the  boiling  is  to  be  continued  until  the  odor 
ceases  to  be  distinguished  clearly.  The  liquid  is  now  cooled,  and 
to  it  should  be  added  1  drop  of  a  solution  containing  1  part  of 
resorcinol  in  200  parts  of  water.  A  portion  of  this  liquid  is  then 
poured  cautiously  into  a  second  tube  containing  pure  sulphuric  acid, 
in  such  a  way  that  the  two  liquids  shall  not  mix,  the  tube  being 
held  in  an  inclined  position;  this  tube  is  allowed  to  stand  for  three 
minutes,  and  then  slowly  rotated.  No  rose-red  ring  should  show 
at  the  line  of  contact  of  the  two  layers  (absence  of  more  than  2  per 
cent,  of  methyl  alcohol). 
