CONSTITUTION OF ANTHRACENE OR PARANAPHTHALINE. 687 
heated with strong sulphuric acid they fuse, and bromine and hydrobromic acid 
are expelled. On digestion with alcoholic potash they immediately become 
yellow, and are converted into another compound. When heated to 348° F. 
they become brown, and at 361° fuse and give off bromine. Analysis gave the 
following results :— 
4:990 grains of carbonic acid, and 
5'313 grains of sexbromide of anthracene gave 
I 
0:°760 grains of water. 
6°159 grains of sexbromide of anthracene gave 
5°835 grains of carbonic acid, and 
0-880 grains of water. 
II 
5-652 grains of sexbromide of anthracene gave 
III.< 5-310 grains of carbonic acid, and 
1-730 grains of water. 
7°540 grains of sexbromide of anthracene gave 


. 12°818 grains of bromide of silver. 
Experiment. Calculation. 
ee ~ 
I. Il. III, Iv. 
Carbon, ‘ : 25°62 25°84 25°62 e 25:53 C,, 168 
Hydrogen, . A 1:59 1:59 1:72 oe Progr dt 4 ho 
Bromine, : ae ae 72°33 72°95 Br, 486 
100-00 658 
The formula is C,, H,, Br,, and the substance is produced by the direct absorption — 
of six equivalents of bromine. 
Quadribrominated Anthracene.—W hen the preceding compound is treated with 
an alcoholic solution of potash, it swells up considerably and acquires a bright 
sulphur-yellow colour, and the solution contains bromide of potassium. This 
change occurs in the cold, but it is more convenient to heat the solution. The 
yellow powder is collected on a filter, washed, dried, and crystallised from 
boiling benzole. It is thus obtained in long yellow needles, having a fine silky 
lustre. It is very sparingly soluble in cold alcohol, ether, and benzole—more 
so when hot. Boiling benzole is its best solvent, but even of this it requires above 
a hundred times its weight. It fuses at 460°, and gives a dark coloured mass, 
which has undergone partial decomposition. The portions used for analysis 
were crystallised from benzole, and then washed with ether :— 
6-400 grains of acid, and 
5°110 grains of quadribrominated anthracene gave 
i; 
0°780 grains of water. 
6:250 grains of carbonic acid, and 
5021 grains of quadrobrominated anthracene gave 
1G 
0°750 grains of water. 
6°560 grains of carbonic acid, and 
5-271 grains of quadribrominated anthracene gave 
III. 
0:°792 grains of water. 
