Am.  Jour.  Pharm.  ) 
Aug,  1876.  j 
Varieties. 
379 
VARIETIES. 
On  Anthraflavon  and  an  Accessory  Product  of  the  Manufacture  of 
Artificial  Alizarin.  By  M.  A.  Rosenstiehl.- -The  author  showed  in  1874 
{Comptes  Kendusy  lxxix.,  p.  764)  that  the  anthraflavon  of  Barth  and  Sennhofer,  if 
melted  with  caustic  potassa,  gives  simultaneous  rise  to  two  coloring  matters,  one 
of  which,  soluble  in  benzin  and  in  alum  water,  dyes  mordanted  tissues  shades  bor- 
dering upon  those  of  alizarin,  whilst  the  other,  insoluble  in  the  same  liquids,  ap- 
proaches purpurin  ;  the  shades  obtained  in  dyeing  are,  in  brightness  and  solidity^ 
comparable  to  those  of  madder.  The  former  of  these  colors  is  produced  in  such 
small  quantities  that  its  examination  has  not  been  hitherto  possible.  The  latter  is 
more  plentiful,  and  is  an  isomer  of  purpurin  approaching  the  isopurpurin  or  anthra- 
purpurin  of  Perkin.  Anthraflavon  itself  is  a  mixture  of  two  isomers  of  alizarin? 
distinguished  by  their  behavior  with  bases.  The  one  forms  a  soda  salt  very  soluble 
in  water  5  it  dissolves  in  baryta  water,  which  it  colors  a  deep  orange  yellow,  com- 
bines with  gelatinous  alumina  to  form  an  orange  lake,  and  if  melted  with  caustic 
potash  between  1350  and  1500  it  forms  the  isomer  of  purpurin  just  mentioned.  The 
other  yields  a  soda  salt  sparingly  soluble,  and  readily  crystallisable  ;  it  is  insoluble 
in  cold  baryta  water,  does  not  combine  with  gelatinous  alumina,  and  if  melted  with: 
potassa  at  the  same  temperature  it  does  not  give  rise  to  a  coloring  matter  ;  a  little 
only  is  formed  at  a  higher  temperature,  with  the  destruction  of  a  large  proportion  of 
the  substance.  This  second  body  can  be  obtained  in  the  form  of  fine  silky  needles,, 
which  in  bulk  present  the  yellow  color  of  chromate  of  lead,  and  recalls  the  aspect  of 
chrysophanic  acid.  This  body  is  identical  with  an  accessory  product  of  the  manu- 
facture of  artificial  alizarin  from  the  works  of  Przibram  &  Co.,  of  Praz. — Chem.. 
News,  July  14,  1876. 
New  Color. — Rosenstiehl  has  obtained  a  coloring  matter  in  yellow  metallic 
lamellae  by  acting  upon  dry  artificial  alizarin  with  nitrous  acid.  With  alumina  it 
dyes  yellow,  and  with  iron  mordants  a  red-violet,  both  of  which  colors  can  be 
brightened  with  boiling  soap  lyes.  It  dyes  best  in  distilled  water  or  with  addition 
of  acetate  of  lime.  Rosenstiehl  considers  it  as  nitro-alizarin. — Chem.  Neivsr 
July  7th. 
Resorcin  Black.  By  M.  R.  Wagner. — If  to  an  aqueous  solution  of  resor- 
cin  there  is  added  sulphate  of  copper  and  then  ammonia,  enough  to  re-dissolve  the 
precipitate  first  formed,  a  deep  black  liquid  is  obtained  which  dyes  wool  and  silk 
black,  and  which  may  possibly  be  used  as  ink. —  Chem.  Neivs,  June  23,  1876. 
MINUTES  OF  THE  PHARMACEUTICAL  MEETING. 
A  Pharmaceutical  Meeting  was  held  July  18th,  1876,  Edward  Gaillard  in 
the  chair.  Prof.  Remington  donated  to  the  Cabinet  from  Cramer  &  Small,  a  stone 
jar  in  which  balsam  of  tolu  was  imported  a  box  which  held  25  musk  pods,  and  a 
sample  of  Persian  opium. 
