52 
Neiv  Vegetable  Coloring  Matter, 
j  Am.  Jour.  Pharm. 
(      Feb.,  1881. 
pounds.  The  above  table  has  been  prepared,  showing  the  action  of 
a  series  of  reagents  upon  several  of  the  common  coloring  principles 
with  the  results  obtained  with  this  coloring  material.  The  brasilin  and 
santalin  were  extracted  directly  from  the  woods  with  alcohol,  and  the 
other  two  were  alcoholic  solutions  of  the  crystallized  coloring  matters. 
The  following  references,  all  of  them  from  the  "  Berichteder  Chem. 
Gesellschaft,"  show  what  has  been  done  with  the  investigation  of  these 
vegetable  coloring  matters  in  late  years:  Franz  Reim — ^^Ueberdas 
Hiematoxylin,"  Ber.,  1871,  p.  329  ;  Adolf  Bfeyer— Ueber  das  Gal- 
lein/'  Ber.,  1871,  p.  457  ;  E.  Kopp — ^'  Ueber  Brasilin  und  Resorcin," 
Ber.,  1873,  p.  446;  C.  Liebermann  and  O.  Burg — Ueber  Brasilin,^^' 
Ber.,  1876,  p.  1883  ;  Richard  Meyer — Verhalten  des  Hsematoxylins- 
bei  der  trockenen  Destination,^'  Ber.,  1879,  p.  1392;  E.  A.  Letts — 
Ueber  das  Phtalein  des  Hfiematoxylins,"  Ber.,  1879,  p.  1651. 
A  comparison  of  the  Beth-a-barra  coloring  material  with  chryso- 
phanic  acid,  the  yellow  coloring  principle  of  rhubarb  and  goa  powder,, 
was  then  made  in  order  to  see  what  resemblance  there  might  exist 
between  the  two. 
Chrysophanic  acid  forms  golden-yellow  scales,  melts  at  162°C.,, 
forms  deep  red-colored  solutions  with  caustic  alkalies  or  ammonia 
from  whicli  the  acid  is  precipitated  in  yellow  flakes  on  neutralizing 
the  solution  with  acid.  Caustic  soda  will  extract  the  color  from  solu- 
tions of  chrysophanic  acid  in  ether,  chloroform,  benzol  or  petroleum 
benzin,  yielding  deep  red  solutions ;  ammonia  will  extract  the  color 
from  solutions  in  ether  or  petroleum  benzin,  but  not  from  chloroform 
or  benzol  solution.  An  ammoniacal  solution  is  precipitated  lilac  by 
acetate  of  lead  and  rose  colored  by  alum. 
The  Beth-a-barra  color  looks  like  chrysophanic  acid,-  but  fuses  at 
135°C. ;  forms  solutions  with  alkalies  like  those  of  chrysophanic  acid. 
Caustic  soda  and  ammonia  both  will  extract  the  color  from  solutions 
in  ether,  benzol,  petroleum  benzin  and  chloroform.  An  ammoniacal 
solution  is  precipitated  brick-red  by  acetate  of  lead,  and  no  compound 
apparently  is  formed  in  alum  solutions.  Chrysophanic  acid,  when 
ignited  with  zinc  dust,  yields  methyl-anthracene ;  this  compound  simi- 
larly treated  yields  phenol-like  bodies  with  the  odor  of  wood-tar  creo- 
sote, and  soluble  in  alkali  with  violet  color.  Finally,  the  percentage 
composition  of  this  compound,  before  quoted,  differs  too  decidedly 
from  that  of  chrysophanic  acid  whicli  requires  70*87  per  cent,  carbon 
and  3 '94  per  cent,  hydrogen. 
