'^SptLmber^^i92o; }  United  States  Pharmacopoeial  Revision.  65  i 
found  are  merely  those  of  phraseology;  for  instance;  in  the  first 
paragraph  on  page  593  it  is  stated  that  alkaloids  "are  more  or  less 
soluble  in  alcohol,  chloroform,  ether,  amyl  alcohol,  benzene,  petro- 
leum benzin,  or  mixtures  of  several  of  these."  The  latter  phrase 
is  somewhat  misleading,  as  it  conveys  the  impression  that  the  alka- 
loids are  not  soluble  in  a  mixture  of  two  of  the  solvents  but  only  in  a 
mixture  of  more  than  two,  or,  in  other  words,  of  several.  In  our 
opinion,  the  latter  part  of  this  sentence  should  be  changed  to  read  as 
follows:  "More  or  less  soluble  in  alcohol,  benzene,  petroleum  ben- 
zin, or  a  mixture  of  two  or  more  of  these."  The  same  sort  of  error 
occurs  in  paragraphs  three  and  four,  page  594.  In  paragraph  three 
it  is  stated  that  a  mixture  of  more  than  one  volume  of  chloroform 
to  one  volume  of  ether  will  separate  in  the  bottom  of  the  sep- 
arator. As  a  mixture  of  equal  volumes  of  chloroform  and 
ether  is  also  heavier  than  water,  the  sentence  should  read  as  fol- 
lows: "A  mixture  of  one  volume  or  more  of  chloroform  to  one 
volume  of  ether  will  settle  in  the  bottom  of  the  separator."  The 
correction  of  paragraph  four  is  of  the  same  order,  as  the  phrase 
should  read:  "Two  volumes  or  more  of  ether  to  one  volume  of 
chloroform." 
Indicator. — It  is  recommended  that  methyl  red  be  specifically 
directed  for  use  in  the  various  assay  processes  instead  of  cochineal. 
Methyl  red  gives  clear  end-points  in  all  cases,  whereas  the  end-point 
with  cochineal,  when  assaying  aconite,  ipecac,  nux  vomica,  or  opium, 
is  rather  obscure  and  difficult  to  determine.  Cochineal  could  be, 
permitted  for  alternate  use  as  methyl  red  now  is. 
Detection  of  Alkaloid. — On  page  594,  in  paragraphs  five  and  six,, 
under  the  instructions  for  determining  the  presence  or  absence  of 
alkaloid  during  the  various  stages  of  the  assay,  it  is  stated  that  the 
solution  tested  should  show  not  more  than  a  very  faint  cloudiness 
on  the  addition  of  a  drop  of  mercuric-potassium  iodide  T.  S.,  or 
in  the  case  of  caffeine  or  colchicine  on  the  addition  of  a  drop  of 
iodine  T.  S.  Experience  has  shown  that  it  is  necessary  to  "shake 
out"  until  a  negative  test  has  been  obtained,  particularly  in  the 
case  of  extracts,  such  as  powdered  and  solid  extracts  of  belladonna 
leaves,  which  require  more  than  the  usual  number  of  shake-outs. 
Ordinarily,  and  particularly  in  the  case  of  crude  drugs,  three  or 
four  shake  outs  are  sufficient  to  extract  all  of  the  alkaloids,  but  in  the 
case  of  the  belladonna  and  other  extracts  many  more  shake  outs  are 
