662     Detection  of  Cocaine,  Heroine  and  Veronal.  {^J0°buerr 
our.  Pharm. 
919. 
solvent  mixed  and  shaken  with  two  successive  portions  (10  Cc.) 
of  -^q  hydrochloric  acid.  The  aqueous  solution,  after  rendering- 
alkaline  with  ammonia,  is  reextracted  with  chloroform.  The  resi- 
due obtained  after  distilling  off  the  chloroform  may,  where  cocaine 
is  suspected,  be  reextracted  with  benzene,  in  which  this  alkaloid  is 
distinctly  soluble. 
The  final  residues  obtained  are  dried,  weighed,  redissolved  in 
suitable  solvents,  and  aliquot  portions  evaporated  in  small  flat- 
bottomed  porcelain  basins.  One  residue  in  each  case  is  treated  with 
a  few  drops  of  a  2  per  cent,  acetic  acid  solution  and  the  special 
alkaloidal  group-tests  applied,  the  precipitates,  if  any,  being  reserved 
for  microscopical  examination  and  comparison  with  those  obtained 
from  known  alkaloids. 
The  following  notes  on  the  identification  of  certain  narcotics 
may  be  of  interest : 
Veronal  (B.P.  Barbitone,  Diethyl  barbituric  acid). 
"  \c<  >co. 
This  is  a  white  crystalline  substance  with  a  slightly  bitter  taste, 
sparingly  soluble  in  water  (1  part  in  j 50),  and,  when  pure,  has  a 
melting-point  of  191 0  C.  After  extraction  from  viscera  the  melting- 
point  is  frequently  slightly  lower,  about  1860  C.  The  medicinal  dose 
given  in  the  B.P.  is  5  to  10  grains,  whilst  it  is  suggested  by  W.  H. 
Willcox  that  50  grains  may  be  regarded  as  the  minimum  fatal  dose 
for  a  healthy  adult. 
In  cases  of  death  from  veronal  poisoning  the  organs  frequently 
contain  a  fair  amount  of  the  substance,  and,  as  the  latter  is  excreted 
by  the  kidneys,  one  usually  finds  a  distinct  proportion  in  the  urine. 
Sometimes,  however,  a  considerable  period  elapses  between  the  tak- 
ing of  the  fatal  dose  and  the  resulting  death,  and  under  such,  circum- 
stances much  of  the  drug  may  have  been  eliminated. 
Veronal  dissolves  very  rapidly  in  alkaline  solutions  and  is  easily 
extracted  from  an  acid  solution  by  means  of  ether.  The  crystalline 
character  of  the  ethereal  extract  is  to  help  in  its  detection,  as  also 
is  the  melting-point  and  the  fact  that  it  sublimes  completely  if  care- 
fully heated.  The  crystalline  sublimate,  if  any,  yielded  by  the  ex- 
tract may  be  compared  microscopically  with  that  obtained  from 
