298 
The  Pharmacopoeial  Standard. 
Am.  Jour.  Pharm. 
June,  1896. 
the  writer  undertakes  the  responsibility  of  pointing  in  a  general 
way  to  what  may,  under  present  conditions,  be  considered  as  defects 
and  oversights,  but  which  have  not  heretofore  had  an  existence. 
The  substance  under  consideration  may  be  divided  into  three 
classes,  a  few  specimens  of  each  being  herein  mentioned,  and  re- 
marked upon  as  follows : 
(1)  It  is  evident  that  in  many  cases  the  intent  was  not  to  give 
standards  that  must  be  maintained  in  commerce,  but  to  indicate 
what  will  be  the  condition  of  a  substance  when  freshly  and  exactly 
prepared.  As  examples  of  substances  that  will  illustrate  this  phase 
of  the  subject,  I  will  call  attention  to  Class  A,  to  follow,  embracing 
preparations  that  begin  to  change  immediately  and  continue  to  alter 
with  greater  or  less  rapidity  according  to  circumstances. 
(2)  Preparations  in  which  the  qualities  demanded  by  the  phar- 
macopoeial descriptions  are  such  as  to  render  their  production 
impractical  or  unnecessarily  expensive,  as  shown  by  Class  B,  to 
follow. 
(3)  Substances  used  largely  in  the  arts  that  the  demands  of  com- 
merce, necessities  of  manufacture  or  custom  have  established  of 
qualities  different  from  the  standard  of  the  U.  S.  P.  In  such  cases, 
as  shown  by  Class  C,  if  no  great  advantage  accrues  from  the  phar- 
macopoeial quality,  it  is  questionable  as  to  whether  it  is  wise  to 
demand  a  pharmacopoeial  strength  different  from  that  already 
established  in  commerce,  or  different  from  that  established  by  the 
preceding  Pharmacopoeias. 
"An  aqueous  solution  of  several  chlorine  compounds  of  sodium, 
containing  at  least  2-6  per  cent,  by  weight  of  available  chlorine." 
— U.S.  P,  1890. 
A  lot  was  prepared  October  12,  1895,  according  to  the  direction 
of  the  U.  S.  P.,  kept  well  stoppered  and  protected  from  light ;  it 
was  tested  at  different  periods,  with  results  as  follows  : 
CLASS  A. 
(1)  Liquor  Sodce  Chloratce  (Labarraque's  Solution). 
Per  Cent. 
Available 
Chlorine. 
October  12,  1895 
October  14,  1895 
October  24,  1895 
January  20,  1896 
May  6,  1896 
2-56 
2'22 
2-09 
1-87 
178 
