Correspondence. 
Am.  Jour.  Ptaarrn. 
April,  1903. 
powder,  and  finally  the  methods  used  in  its  isolation  and  estimation. 
These  latter  the  author  found  defective,  and  he  proposed  a  simple 
method  whereby  the  powder  was  saponified  with  sodium  hydrate, 
and  the  sodium  cantharidate  thus  formed  was  extracted  with  alum 
solution,  this  extract  yielding,  on  concentration,  crystals  of  can- 
tharidin  and  a  basic  salt  of  alum. 
Since  then  {Jour.  Pharm.  Soc.  Japan,  No.  244,  June,  1902)  Mr. 
Sing  has  modified  this  method  (called  Dr.  Nagai's  Method,  out  of 
courtesy)  somewhat,  and  he  now  recommends  first  extracting  the 
lat  and  cantharidin  with  a  solvent  like  chloroform,  after  which  the 
saponification  is  effected. 
Still  another  method,  which  he  calls  the  "  nitric-acid  process," 
yields  even  better  results.  Twenty-five  grammes  of  the  powder  are 
treated  with  10  c.c.  of  strong  nitric  acid  diluted  to  200  c.c,  the 
whole  evaporated  to  dryness  by  the  use  of  a  little  gypsum  and  the 
residue  extracted  with  chloroform.  The  solution  yields  an  abun- 
dance of  crystals  which  are  accompanied  by  a  very  yellow,  heavy, 
oily  substance  that  can  be  removed  by  the  use  of  a  very  small 
amount  of  ether.  The  cantharidin  is  then  re-crystallized.  By  this 
process  Japanese  cantharides  yielded  1-9591  per  cent,  of  canthari- 
din, melting  at  207-2  io°  C.  F.  Y. 
CORRESPONDENCE. 
UNITED  STATES  PHARMACOPCEIAL  AFFAIRS. 
Dear  Editor  : — The  following  circular  letter,  under  date  of 
March  18th,  from  Prof.  Jos.  P.  Remington,  Chairman  of  the  Com- 
mittee on  Revision  of  the  United  States  Pharmacopoeia,  to  the 
members  of  the  committee,  may  prove  of  interest  to  your  readers. 
Very  truly, 
H.  M.  Whelpley, 
St.  Louis,  March  23,  1903.  Secretary  U.S. P.  Convention. 
Meeting  of  the  Diphtheria  Antitoxin  Committee. — This  special 
^committee  had  its  first  meeting  at  1832  Pine  Street,  on  March  7, 
1903,  the  following  members  being  present:  Dr.  Theobald  Smith, 
'Chairman,  Forest  Hills,  Boston,  Mass.;   Dr.  E.  M.  Houghton, 
Detroit,  Mich.;  Dr.  Joseph  J.  Kinyoun,  H.  K.  Mulford  &  Co.  Lab- 
