144 
Proximate  Plant  Analysis. 
( Am.  Jout.  Pharni. 
\      Marcli,  18S9. 
cent.  It  will  be  seen  from  these  figures  that  but  two  of  the  sam- 
ples contained  less  than  the  92-5  per  cent,  of  absolute  sulphuric 
acid  required  by  the  Pharmacopceia. 
Acidum  Sulphuricitm  Aromaticum. — Charles  W.  Beyerle,  P.D., 
made  an  examination  of  twelve  samples  of  this  preparation  for  the 
purpose  of  estimating  the  amount  of  official  (92-5  per  cent.)  sulphuric 
acid  present  in  them.  The  results  indicated  10  26,  15-33,  12-20, 
11-34,  1026,  13-39,  12-42,  16-41,  11-34,  I]['34>  io- 80  and  9-72  per 
cent.  The  Pharmacopceia  requires  the  preparation  to  contain  about 
20  per  cent,  of  the  official  sulphuric  acid,  the  variation  thus  allowed 
being  between  19  6  and  20-4  per  cent. 
Acidum  Sulphurosum. — John  E.  Coleman,  P.D.,  examined  eight 
samples  of  sulphurous  acid.  All  the  samples  were  clear  and  color- 
less. Sample  8  was  odorless;  the  odor  of  sample  3  was  very  faint. 
All  showed  sulphuric  acid,  and  failed  to  evaporate  without  leaving 
a  residue.  The  official  method  of  estimating  the  sulphur  dioxide 
was  applied  to  the  samples  with  the  following  results:  3*4,3-45, 
0-007,  2-49,  4-3,  1-5,  0-175  and  0002  per  cent.  These  results  show 
a  great  variation  from  the  official  requirement  of  6  4  per  cent,  of 
sulphur  dioxide. 
A  COMMON  ERROR  IN  RECORDED  RESULTS  OE 
PROXIMATE  PLANT  ANALYSIS. 
By  Lyman  F.  Kebi,e;r. 
Under  the  above  title  the  writer  made  a  few  remarks  which  ap- 
peared in  the  January  number  of  this  Journal.  From  a  certain 
portion,  it  might  appear  that  the  schemes  of  analysis  were  being 
criticised,  and  the  editor  justly  appended  a  foot-note,  in  this  connec- 
tion. The  impression  thus  conveyed  is,  however,  incorrect.  It  was 
clearly  stated  at  the  outset,  that  the  remarks  were  in  reference  "  to 
an  error  frequently  made  in  recording  the  results  of  proximate 
plant  analysis."  The  last  sentence  of  the  first  paragraph  imparts 
the  wrong  idea.  Line  seven,  from  the  top  of  this  paragraph,  should 
read,  "  they  are  frequently  recorded  again,"  instead  of,  "  they  must 
necessarily  be  recorded."  The  error  referred  to  is  not  due  to  the 
analytical  schemes,  but  to  inadvertent  recapitulations.  Any  one 
can  ascertain  this  for  himself,  by  consulting  the  literature  of  proxi- 
mate plant  analysis  during  the  past  fifteen  years.  It  will  be  found 
that  the  ash  is  doubly  recorded,  either  in  part  or  as  a  whole,  again 
and  again. 
