254 
Pharmaceutical  Meeting. 
Am.  Jour.  Pharm. 
May,  1901. 
concentration  and  purity  of  the  substance,  and  that  they  served 
simply  as  useful  guides  to  be  considered  in  connection  with  other 
properties.  Where  the  substance  occurs  in  sufficient  quantity  to  be 
crystallized,  the  speaker  considered  the  microscopical  examination 
one  of  the  most  reliable  of  tests  for  establishing  its  identity. 
Mr.  Freeman  P.  Stroup,  Instructor  in  Chemistry  in  the  College, 
made,  at  the  request  of  Professor  Kraemer,  an  examination  of  some 
powders  which  were  submitted  him  by  Professor  Lloyd,  the  compo- 
sition of  which  was  as  follows,  although  this  composition  was  not 
known  at  the  time  the  tests  were  made,  with  the  exception  of  No.  I : 
(i)  Mixture  of  hydrastine,  I  part,  and  morphine,  9  parts.  (2)  Mix- 
ture of  No.  1,  plus  10  per  cent,  of  strychnine.  (3)  Mixture  of  hydras- 
tine,  1  part,  and  morphine,  9  parts.  (4)  Mixture  of  No.  1,  plus  25 
per  cent,  of  strychnine.  (5)  Mixture  of  No.  1,  plus  50  per  cent,  of 
strychnine.  (6)  Mixture  of  No.  1,  plus  10  per  cent,  of  strychnine. 
(7)  Mixture  of  No.  1,  plus  25  per  cent,  of  strychnine. 
The  tests  were  carried  out  on  crucible  lids,  and,  as  nearly  as  pos- 
sible, under  the  same  conditions,  and  a  sample  of  pure  strychnine 
was  tested  under  the  same  conditions  in  order  to  note  similarities  or 
differences  in  behavior. 
In  each  case  eight  drops  C.  P.  sulphuric  acid  (sp.  gr.  1-84),  weigh- 
ing approximately  '230  grammes,  was  placed  upon  crucible  lid,  and 
to  it  was  added  a  small  portion  (-oio  to  -012  grammes)  of  the  pow- 
der to  be  tested,  and  stirred  around  with  a  glass  rod  until  dissolved. 
A  fragment  of  potassium  bichromate  size  of  pin  head  (about  -006 
gramme)  was  then  dropped  in  and  moved  about  with  glass  rod. 
In  the  case  of  the  strychnine  a  violet-blue  streak  followed  the 
bichromate,  whether  the  crystal  was  moved  rapidly  or  slowly,  but 
the  color  was  transient,  changing  in  one  or  two  seconds  to  yellow 
or  orange. 
In  the  case  of  all  the  others,  if  the  crystal  was  moved  rapidly 
the  streak  was  greenish-yellow,  changing  rapidly  to  purplish- 
violet,  while  a  slow  tracing  with  the  crystal  produced  the  pur- 
plish-violet streak  at  once.  The  shades  produced  were  not  strictly 
identical,  but  so  nearly  alike  that  a  description  could  not  be  given 
that  would  give  a  definite  idea  of  their  differences.  No.  3  and  No. 
4  had  a  sort  of  blue-grayish  cast,  and  No.  1  gave  the  deepest  shade, 
being  practically  a  purple.  In  the  case  of  No.  5  the  purplish  color 
disappeared  after  about  an  hour,  and  thereafter  the  moving  of  the 
