Dec.'i'isS^"'  }       ^^^^  Coloring  Matter  of  Flowers. 
601 
prepared  by  making  an  infusion  of  one  part  of  violet  petals  with  two 
parts  of  boiling  water,  and  dissolving  in  the  clear  liquid  one-third  its 
weight  of  table  salt;  if  kept  in  small  well-corked  vials,  this 
solution  is  stated  to  remain  unaltered  in  the  sunlight.  The  blue 
flowers  of  the  larkspur  (Delphinium),  and  of  the  columbine 
(Aquilegia),  treated  in  a  similar  manner,  can  also  be  used  as  chemical 
reagents. 
Regarding  the  chemistry  of  the  blue  coloring  matter,  the  principal 
investigations,  embracing  blue  flowers  of  different  orders,  were  pub- 
lished by  Marquardt  in  1835,  and  by  Fr^my  and  Cloez  in  1854,  in  ad- 
dition to  which  a  large  number  of  observations  on  the  coloring  mat- 
ter of  certain  flowers  might  be  mentioned.  Marquardt  named  the 
blue  coloring  matter  anthocyan,  the  cyanin  of  Fremy  and  Cloez,  the 
latter  name  having  been  more  recently  appropriated  for  a  blue  dye- 
stuff  derived  from  chinoline.  The  chemists  named  regard  the  col- 
oring principles  of  all  blue  flowers  as  identical,  the  blue  compound 
being  amorphous,  soluble  in  water  and  alcohol,  but  insoluble  in 
absolute  alchohol,  ether,  volatile  oils,  etc.  Its  solution  is  sometimes 
rapidly  decolorized  on  exposure,  also  by  reducing  agents  ;  it  is  col- 
ored red  by  acids,  and  green  by  alkalies,  and  yields  with  lead  ace- 
tate a  green  precipitate.  The  coloring  matter  of  red  flowers  is  re- 
garded as  antho-cyan  (cyanin)  colored  red  by  acids.  Even  white 
flowers  often  contain  the  same  coloring  matter,  and  hence  are  col- 
ored green  by  alkalies.  The  coloring  matter  of  various  berries  is 
changed  to  green  by  alkalies,  and  to  red  by  acids,  and  has  been 
regarded  as  identical  with  that  of  blue  flowers,  but  derivatives 
of  quercitrin  and  rutin  are  likewise  known,  having  similar  reac- 
tions. 
However,  a  large  number  of  investigations  have  been  made  on 
red,  purple  and  blue  berries,  proving  that  in  many  instances  their  col- 
oring matters  show  decided  differences  in  behavior.  Similar  observa- 
tions have  also  been  made  with  many  red  and  purple  flowers, 
which  contain  red  coloring  matters  not  agreeing  with  anthocyan  in 
reactions.  But  the  blue  flowers  examined  by  many  chemists  show 
in  so  far  identical  reactions,  as  they  are  turned  red  by  acids,  and 
green  by  alkalies.  Some  minor  differences  in  behavior  have  been 
ascribed  by  Filhol  (1860)  to  the  presence  of  sugar  and  other  com- 
pounds. 
The  identity  of  the  blue  coloring  matters  of  different  flowers  has 
