Am.  Jour.  Pharm.  "1 
November,  1907.  i 
Poison  Sumac. 
507 
Fifty  grammes  of  the  juice  were  placed  in  a  steam  distillation 
apparatus  and  distilled  for  five  hours.  The  distillate  was  neutral  to 
litmus,  The  emulsion  in  the  distilling  flask  was  scarcely  changed 
in  appearance.  Twenty  cubic  centimeters  of  10  per  cent.  H2S04 
were  then  added  to  the  contents  of  the  flask  and  the  distillation  con- 
tinued for  five  hours  more.  The  emulsion  was  broken  up  by  this 
treatment,  so  that  the  mixture  separated  into  two  layers  on  standing 
and  cooling.  This  distillate  was  very  slightly  acid  to  litmus.  A 
trace  of  alkali  was  added  to  each  of  the  distillates,  after  which 
they  were  evaporated  separately  to  a  small  bulk.  No  acetic  acid 
could  be  detected  in  either  by  tests  with  ferric  chloride,  sulphuric 
acid  and  ethyl  alcohol,  or  arsenous  acid  and  alkali.  The  distillates 
and  the  residue  in  the  distilling  flask  were  each  separately  shaken 
out  with  ether  and  the  ethereal  layers  evaporated.  Only  mere  traces 
of  a  pale  yellow,  oily  residue  remained  from  the  distillates,  while 
the  contents  of  the  distilling  flask  yielded  about  45  grammes  of  a 
dark  red,  oily  substance.  None  of  these  oily  residues  were  poisonous. 
As  the  original  material  was  highly  poisonous,  it  is  evident  that  the 
poisonous  properties  of  the  lac  are  destroyed  by  long-continued 
heating. 
In  our  investigations  we  have  employed  two  methods  of  testing 
for  poisonous  properties.  The  first  was  one  used  by  Stevens23  in  his 
work  on  Japanese  lac.  A  hole  about  6  mm.  in  diameter  was  cut 
with  a  cork  borer  through  a  piece  of  gummed  paper,  the  paper 
pasted  on  the  arm  and  the  suspected  substance  applied  to  the  open- 
ing by  means  of  a  glass  rod.  In  thirty  minutes  the  paper  was 
removed  and  the  arm  thoroughly  washed  with  ether.  If  the  sub. 
stance  were  poisonous  the  spot  became  red  and  began  to  itch  in 
twenty  to  thirty  hours.  The  second  method  was  one  used  by  Dr.. 
Jadassohn,24  of  the  University  of  Bern,  and  reported  by  Tschirch 
and  Stevens.  It  consisted  in  rubbing  a  drop  of  the  suspected  sub- 
stance by  means  of  a  glass  rod  upon  the  inner  surface  of  the  ear  of 
a  rabbit.  If  poisonous,  redness  and  swelling  would  appear  in  two  to 
five  or  six  days,  followed  by  watery  blisters  and  even  by  necrosis 
of  the  superficial  layers  of  the  skin.  This  condition  would  gradu- 
ally disappear  after  about  two  weeks.    In  the  case  of  the  rabbit  we 
Am.  J.  Pharm.,  78,  63. 
Arch.  Pharm.,  243,  528. 
