118 I. Remsen on Nitroparasulphobenzoie Acid. 
0:2475 grams salt lost 0°022 grams on being heated to 200°; 
and gave 0°0963 grams BaSO4=0-05662 grams Ba. 
Found. 
Calculated. 
2(C*H5SO5) 402 67"79 
Ba 137 23°10 22°88 
3H?0 54 9°11 8°88 
593  100°00 
I next endeavored to introduce the group NO? into para- 
sulphaminbenzoic acid. Fuming nitric acid was first employed 
for this purpose. When thisis boiled with the amine-acid, solu- 
tion takes place, and, on diluting this solution with water, noth- 
ing is precipitated. The change effected is, however, the same 
as that effected by Nordhausen sulphuric acid, viz: the NH* 
group is simply converted into OH, and parasulphobenzoie acid 
thus regenerated. The latter acid was in this instance 
readily recognized. The solution was evaporated to dryness 
on the water bath and all nitric acid thus removed. On now 
dissolving in water, neutralizing, as above, with baric carbonate, 
adding chlorhydrie acid and allowing to cool, the acid barium 
salt was deposited. It was identified beyond a doubt by the 
aid of the following analysis: 
0°5825 grams salt lost 0-0483 grams on being heated to 200°; 
and gave 0°2095 grams, BaSO*=0°1232 grams Ba. - 
Calculated. * Found. 
2(C7H5SO5) 402 67°79 
Ba 137 23°10 os°it 
8H20 54 9°11 9°07 
593 100°00 ‘ 
These experiments then only show that parasulphobenzole 
acid is an exceedingly stable compound, as it resists the action 
