526 '  British  Pharmaceutical  Conference.  {Am-octu!"i8P37arm" 
kinds  obtained  from  San  Domingo  and  Jamaica.  As  to  the  condition  in 
which  the  wood  was  to  be  used  the  Pharmacopoeia  was  silent,  and  ignored 
the  fact  that  the  wood  in  logs  and  that  ordinarily  sold  in  chips  or  in  the  form 
of  a  coarse  powder,  were  most  essentially  different  from  each  other  from  a 
chemical  point  of  view,  since  the  ground  wood  or  chips  as  met  with  in 
commerce  had  undergone  a  long  process  of  fermentation  by  being  laid  up 
with  water  in  heaps  and  exposed  to  the  air  for  weeks.  The  great  difference 
between  the  two  was  well  known  to  those  engaged  in  dyeing  and  calico- 
printing,  and  to  technical  chemists  acquainted  with  these  processes;  bat  it 
was  little  known  to  and  not  at  all  appreciated  by  pharmacists.  The  author 
fully  explained  the  difference  in  the  chemical  nature  of  the  two  woods,  and 
expressed  the  opinion  that  the  fresh  or  unfermented  wood  ought  only  to  be 
used  in  pharmacy,  the  aged  or  fermented  wood  being  very  unsuitable  for 
the  decoction  and  the  extract,  especially  for  the  latter,  both  from  a  pharma- 
ceutical and  from  a  medical  point  of  view.  He  had  no  doubt  in  his  mind 
that  the  framers  of  the  Pharmacopoeia  meant  the  unfermented  wood,  as 
this  alone  had  the  sweetish  taste  alluded  to  in  the  characters.  The  last 
question  he  answered  in  the  negative,  asserting  that  fermented  chips  were 
almost  exclusively  used  by  pharmacists  and  wholesale  houses  for  the  B.  P. 
preparations.  Unfermented  chips  were  rarely  met  with  in  commerce,  and, 
to  his  knowledge,  were  never  sold  to  retailers.  He  thought  that  pharma- 
cists or  wholesale  druggists  should  prepare  their  own  extract,  as  that  im- 
ported so  largely  from  France  and  America  was  not  pure  enough  for  phar- 
maceutical purposes.  He  would  recommend  in  the  place  of  the  extract  a 
liquor  hsematoxyli,  representing  its  own  weight  of  wood,  which  after  settling 
was  an  elegant  and  very  permanent  preparation.  He  gave  fall  details  as  to 
how  this  should  be  made. 
Logwood  as  a  reagent. — Mr.  Siebold  also  read  a  Note  on  the  Application  Of 
Dyewoods  in  Chemical  Analysis.  He  said  that  much  had  been  written  re- 
garding the  application  of  logwood  tincture  for  the  detection  of  alum  in 
bread  and  of  traces  of  heavy  metals  in  potable  water;  but  it  had  never  been 
properly  pointed  out  what  kind  of  logwood  should  be  employed  for  such 
purposes.  He  recommended  the  use  of  aged  or  fermented  wood  for  the 
preparation  of  the  tincture  intended  for  testing,  since  its  indications  were 
far  more  delicate.  He  showed  experimentally  how  this  test  could  be  made 
to  show  the  presence  of  one  part  of  copper  in  four  millions,  one  of  aluminium 
in  seventeen  millions,  and  one  of  tin  in  the  same  proportion  of  water;  also, 
now  it  should  be  best  applied  for  the  detection  of  alum  in  flour  and  bread 
He  also  warmly  recommended  the  fustic  test  described  by  Goppelsroeder 
for  the  detection  of  traces  of  aluminium  in  colorless  liquids. 
Examination  of  cacao  butter,  by  Mr.  E.  J.  Millard.  This  paper  at  first  dealt 
with  the  statement  in  the  British  Pharmacopoeia  that  the  melting  point 
occurs  "  usually  between  30°  and  35°  C,"  the  author  affirming  that  starting 
with  an  original  sample  of  pure  cacao  butter,  the  melting  point  of  which  was 
33°  C,  he  had  found  that  the  addition  of  as  much  as  ten  per  cent,  of  paraffin, 
wax  or  tallow,  only  varied  the  melting  points  slightly  outside  the  limits  official- 
ly given  as  "  usual."    Better  results  were  obtained  with  the  test  given  in  the 
