Am.  Jour.  Pharrn. ) 
November,  1907.  J 
Poison  Sumac. 
odor,  suggestive  of  the  original  juice.  Evidently  the  odor  of  the 
plant  is  due  to  this  oily  substance.  A  drop  of  it,  when  allowed  to  sink 
into  paper,  produces  a  "  grease-spot  "  like  a  true  fat  or  oil.  It  is 
not  a  fat,  however,  as  it  produces  no  glycerol  when  saponified.  It 
has  a  faintly  acid  reaction,  a  specific  gravity  of  0-9888  at  25 0  C./ 
25 0  C,  and  is  soluble  in  the  usual  solvents  for  resins  and  oils. 
When  tested  on  the  ear  of  a  rabbit  it  was  found  to  be  very  poisonous. 
It  does  not  possess  the  properties  of  a  glucoside  or  of  an  alkaloid. 
When  dissolved  in  chloroform  it  unites  with  bromine  and  with  iodine 
with  great  violence,  with  copious  evolution  of  hydrobromic  or  hydri- 
odic  acids.  On  evaporating  the  solvent,  a  hard,  black  varnish 
remains,  which  is  very  lustrous  and  apparently  durable. 
Following  the  nomenclature  adopted  by  Tschirch  and  Stevens  in 
their  work  on  Japanese  lac,  we  have  designated  the  alcoholic- 
soluble  portions  of  the  latter  from  Rhus  vernix  as  resins,  though  they 
do  not  possess  all  the  properties  generally  attributed  to  these  bodies. 
In  general,  however,  their  properties  were  found  to  conform  more 
nearly  to  the  resins  than  to  any  other  class  of  organic  products. 
SEPARATION  OF  THE  LAC-RESINS. 
In  all  proportions  the  crude  resin  was  found  not  to  be  completely 
soluble  in  methyl  alcohol,  oil  of  turpentine,  and  petroleum  benzin. 
With  slight  deviations,  the  method  devised  by  Tschirch  and  Stevens27 
for  the  separation  of  the  lac-resins  of  Japanese  lac  was  used  in  our 
work.  As  finally  adopted  the  method  was  as  follows  :  100  c.c.  oi 
the  crude  resins  were  dissolved  in  900  c.c.  of  petroleum  benzin 
(b.  p.,  below  500),  forming  a  clear,  dark  amber- red  solution.  This 
was  then  slowly  poured  with  stirring  into  9,000  c.c.  of  cold  benzin  ; 
a  dense,  brownish-gray  cloud  was  immediately  formed,  which  slowly 
subsided.  At  the  end  of  twenty-four  hours  the  supernatant  liquid 
was  clear  and  could  be  decanted  with  ease.  A  red-brown,  semi-fluid 
mass  remained,  which'  was  insoluble  in  fresh  benzin. 
BENZIN-INSOLUBLE  RESIN. 
The  benzin-insoluble  resin  was  washed  repeatedly  by  covering  it 
with  benzin  in  a  shallow  dish  and  stirring  with  a  glass  rod  until 
the  washings  became  colorless.  On  drying  the  residue  over  H2S04 
under  reduced  pressure,  a  very  viscous,  red-brown,  resinous,  sticky 
27  Arch.  Pharm.,  243,  518. 
