Am.  Jour.  Pharm.  ) 
January,  1920.  ) 
Current  Literature. 
51 
either  failed  or  deliberately  refused  to  send  in  the  reports,  conserva- 
tive individual  estimates  on  such  delinquent  concerns  have  been 
made.  These  estimates,  which  are  included  in  the  figures  given, 
comprise  only  6  per  cent,  of  the  total  production  shown.  About 
lo  per  cent,  of  the  total  turpentine  stocks  and  about  7  per  cent,  of 
the  total  rosin  stocks  shown  as  in  the  hands  of  consumers  are  es- 
timates on  such  individual  concerns  from  which  no  information  was 
received. 
The  value  of  these  estimates  to  the  individual  concern  and  to  the 
entire  consuming  or  producing  industry  depends  on  their  accuracy 
and  prompt  issue.  It  was  hoped  to  publish  the  figures  several 
months  ago,  but  their  issue  was  held  up  by  lack  of  cooperation  on 
the  part  of  certain  producers  and  consumers.  It  is  hoped  that  in  the 
future  a  more  willing  cooperation  on  the  part  of  producers  and  con- 
sumers may  be  secured,  to  the  mutual  welfare  of  the  interests  of 
both.  However,  the  failure  of  a  small  percentage  of  producers  or 
consumers  to  submit  their  data  will  not  prevent  the  publication  of 
these  statistics,  but  only  serve  to  delay  their  issue,  as  estimates  must 
be  resorted  to  in  every  such  case. 
CURRENT  LITERATURE. 
SCIENTIFIC  AND  TECHNICAL  ABSTRACTS. 
Estimation  of  Arse^nic  in  Substitute^d  PhhnyIvArsinic  Acids 
AND  Thkir  Reduction  Products. — R.  G.  Fargher  (/.  Chem.  Soc, 
1919,  pp.  115-116,  982-992). — Ewins  {Analyst,  42:  50,  1917)  considers 
that  the  method  devised  by  Lehmann  {Apoth.  Zett.,  27:  545,  1912; 
Analyst,  37:  415,  1912)  for  the  estimation  of  arsenic  in  salvarsan  and 
neosalvarsan,  while  applicable  to  some  derivatives,  fails  entirely 
in  many  cases,  owing  to  the  fact  that  the  preliminary  treatment  with 
sulphuric  acid  and  permanganate  fails  to  bring  about  complete 
oxidation.  It  has  now  been  found  possible  by  the  use  of  the  modi- 
fication described  below  to  extend  this  estimation  to  many  substi- 
tuted phenylarsinic  acids  containing  nitro-,  amino-,  hydroxy-, 
methoxy-,  bromo-,  and  other  groups.  Some  of  the  powdered  sub- 
stance (0.2  Gm.)  is  weighed  and  intimately  mixed  in  a  250  Cc. 
flask  with  i  Gm.  of  potassium  permanganate.  Five  Cc.  of  50 
per  cent,  sulphuric  acid  are  added,  followed  by  a  further  10  Cc. 
