Am  jour.  Pharm.  i  The  Purity  Rubric  and  US.P.  Tests.  63 
February, 1910.    )  J  0 
THE  PURITY  RUBRIC  AND  THE  U.S.P.  TESTS.* 
With  Notes  on  Quantitative  Methods  for  Certain  Pharmacopoeial 
Compounds. 
By  Atherton  Seidell  and  M.  I.  Wilbert. 
Division  of  Pharmacology,  Hygienic  Laboratory,  United  States  Public  Health 
and  Marine-Hospital  Service,  Washington,  D.  C. 
As  has  been  repeatedly  pointed  out,  the  Federal  and  States  Pure 
Food  and  Drug  laws  have  given  to  the  Pharmacopoeia  of  the  United 
States  an  entirely  different  standing  from  that  occupied  by  it  at  the 
time  that  the  present  official  revision  was  authorized  by  the  Phar- 
macopoeial Convention,  which  met  in  May,  1900,  and  it  is  also  well 
known  that  the  Pharmacopoeial  Convention  which  is  to  be  held  in 
the  City  of  Washington  in  May,  1910,  will  meet,  as  a  legally  char- 
tered organization,  under  entirely  different  conditions  from  those 
prevailing  at  any  one  of  the  previous  nine  conventions.  The  respon- 
sibilities assumed  by  the  delegates  attending  this  convention  are 
therefore  such  that  they  and  all  others  who  are  in  any  way  interested 
in  the  scope  and  content  of  the  Pharmacopoeia  of  the  United  States 
should  thoroughly  inform  themselves  beforehand  on  the  general 
principles  that  will  come  up  for  discussion. 
From  the  point  of  view  of  the  chemist,  no  one  feature  of  the 
prospective  revision  of  the  Pharmacopoeia  is  of  greater  importance 
than  the  establishment  of  reasonable  standards  of  strength  and 
purity,  and  the  co-relating  of  the  several  tests  and  assays  with  the 
requirements  under  what  has  become  known  as  the  purity  rubric. 
Our  Chairman,  in  his  recent  circular  letter,  calls  renewed  atten- 
tion to  the  fact  that,  "  in  many  cases  the  Pharmacopoeia  requires 
that  its  products  shall  be  of  a  definite  strength  or  purity  without 
supplying  the  method  to  secure  such  results." 
It  is  also  well  known  that  while  many  of  the  chemical  tests  in 
the  U.S.P.  are  described  in  detail,  others  are  but  briefly  outlined, 
and  in  connection  with  some  the  language  used  is  ambiguous  even  to 
the  trained  chemist  and  certainly  meaningless  or  misleading  to  those 
of  limited  experience. 
Many,  if  not  all  of  you,  will  agree  with  the  dictum  that  if  the 
Pharmacopoeia  of  the  United  States  is  to  serve,  as  it  really  should, 
*  Read  at  the  Division  of  Pharmaceutical  Chemistry  of  the  American 
Chemical  Society,  December,  1909. 
