64 Appendix. 



2. Farther oxidation to dioxyanthraquinone. 21 



Anthraquinone, C 14 H 8 O 2 . 



Dioxyanthraquinone or Alizarin, C 14 H 6 (OH) 2 O 3 . 



The history of this triumph may be indicated as follows : 22 



(21) First, C 14 H 10 +3O=C,4H 8 O 2 +H 2 O. 



Second, C 14 H 8 O 2 +2H 2 S0 4 =C 14 H 6 (HSO 3 ) 2 O 2 -f-2H 2 O. 



[2K 2 SO 3 -f-4H 2 O. 

 C l4 H 6 (OK) 2 2 -f-2HCl=C 14 H 6 (OH) 2 O 2 +2KCl. 



(22) Artificial prodcution of Alizarin: ROSCOE: Chem. News, xxi., 185; 

 Amer. Reprint, p. 332 (1870). 



