ADAugust,^l9oa7^m■}    Pennsylvania  Pharmaceutical  Association.  367 
An  attempt  to  adapt  the  official  assay  for  formaldehyde  to  the 
assay  of  benzaldehyde  failed. 
Treatment  with  an  excess  of  sodium  bisulphite  and  titration  of 
the  excess  of  bisulphite  with  iodine  V.S.  also  failed,  owing  to  the 
difficulty  in  determining  the  end  reaction. 
Tinctura  Iodi. — By  A.  E.  Pflaum.  A  number  of  samples  of  tincture 
of  iodine  obtained  from  different  pharmacists  were  assayed.  All 
those  containing  potassium  iodide,  made  by  the  new.  official  process, 
were  of  the  required  strength.  Two  samples  containing  no  potas- 
sium iodide  were  deficient  in  iodine. 
Acidum  Hydrochloricum  Dilution. — By  S.  H.  Feldman.  Ten 
samples  of  diluted  hydrochloric  acid  obtained  from  different  phar- 
macists were  assayed,  the  results  ranging  from  9-5  to  12-3  per  cent. 
HC1,  average  11-05  Per  cent. 
THE  PENNSYLVANIA  STATE  PHARMACEUTICAL  ASSO- 
CIATION MEETING, 
By  Charges  H.  La  Wall. 
{Concluded from  page  341.) 
ABSTRACTS  OF  PAPERS. 
Cataplasm  of  Kaolin. 
I.  V.  S.  Stanislaus. 
A  difference  in  commercial   kaolin  is    reported,  especially  as 
regards  the  amount  of  moisture  which  was  found  to  be  present,  run- 
ning as  high  as  14-2  per  cent,  in  one  of  the  samples,  and  affording 
an  explanation  as  to  why  different  quantities  of  glycerin  are  required 
by  different  samples  of  kaolin  in  order  to  make  a  product  which 
shall  at  all  times  be  uniform.    The  difference  in  the  appearance  of 
the  samples  when  examined  microscopically,  and  as  regards  fineness 
of  texture  was  also  noted,  and  a  variation  in  this  respect  will  pro- 
duce corresponding  variations  in  the  finished  product.    The  following 
deductions  were  made  by  the  author  : 
(1)  Kaolin  should  be  of  the  variety  known  in  commerce  as  bolted 
china  clay.  (2)  It  should  be  heated  for  at  least  one  hour  with  con- 
stant stirring  before  the  boric  acid  is  added.  (3)  The  glycerin  should 
be  heated  to  a  temperature  of  ioo°  C.  before  adding  to  the  mixed 
powders.    (4)  After  the  addition  of  the  glycerin  the  heating  and 
