DR. E. SCHUNCK ON ANTHRAFLAVIC ACID. 233 



water, communicates not the least tinge of colour to alu- 

 mina and iron mordants on calico, however long the liquid 

 may be boiled. The effect produced in dyeing by artificial 

 alizarine would appear therefore to be in no way due to 

 the presence of the acid. 



The analysis of the acid yielded the following results : — 



I. 0*3014 grm. of the substance, dried at ioo° C, gave 

 07808 grm. carbonic acid and 0*1062 water. 



II. 0*3194 grm. gave 0*8288 grm. carbonic acid and 

 0*1140 water. 



III. 0*3226 grm. gave 0*8372 grm. carbonic acid and 

 0*1138 water. 



These numbers lead to the following composition : — 



Experiment. 

 Calculation. 



C 15 180 70-86 



H 10 10 3*93 



4 64 25*21 



I. 



II. 



III. 



70-65 



70-76 



70-77 



V9 1 



3'9 6 



3*9i 



25-44 



25-28 



25-32 



254 IOO'OO IOO'OO IOO'OO ioo*oo 



The barium salt, prepared in the manner above de- 

 scribed, was dried at first in vacuo j then at ioo°, and finally 

 at I20°C, before being analyzed. 



I. 0*4980 grm. of the dry salt gave 0*8026 grm. car- 

 bonic acid and 0*1080 water. 



0*4442 grm. gave 0*2528 grm. sulphate of barium. 



II. 0*4844 grm. gave 0*7892 grm. carbonic acid and 

 0*1052 water. 



0*4904 grm. gave 0*2790 grm. sulphate of barium. 

 The composition of the salt is therefore as follows : — 



Experiment. 



Calculation. 



c 16 . 



Ba . 



o 5 



180 



44-22 



10 



**45 



137 



33*66 



80 



19*67 



407 IOO'OO 



I. 



II. 



43*95 



44*43 



2*40 



2*41 



33*46 



33'45 



20*19 



1971 



IOO'OO 



I0O"0O 



