Mr. A. H. Church on some Derivatives of Xylole. 455 



only salts I prepared, have an acid reaction. Xylidine boils, 

 according to my determination, at 213° to 214°*. The sulphate 

 of xylidine is difficultly soluble in cold water, but crystallizes 

 from hot water in long colourless needles. 



2. Preparation of Nitro-sulphoocylolic and Sulphoxylolic 

 Acids. 



One portion of the pure xylole boiling at 126*2 I treated with 

 fuming nitric acid, &c, and dissolved the nitroxylole thus ob- 

 tained in fuming sulphuric acid : after three days (the liquid 

 having been heated for one hour at 100° C.) the solution was 

 diluted with water, saturated with carbonate of barium and 

 filtered. The filtrate, evaporated nearly to dryness on the water- 

 bath, yielded a lemon-yellow crystalline powder, nitro-sulphoxy- 

 lolate of barium ; in quantity, however, too small to admit of an 

 attempt to isolate the acid, or to form from this barium com- 

 pound other salts by double decomposition. On ignition and 

 treatment of the residue with nitric and sulphuric acidsf, — 



*42 grin, of the barium salt gave '1607 grm. of sulphate of 

 barium, corresponding to 22*5 per cent, of barium ; calculation 

 as C 16 H 8 N0 4 Ba2S0 3 requires 22-94 per cent. 



The remainder of the pure hydrocarbon at my disposal (2 # 5 

 grnis.) was placed in contact with four volumes of Nordhausen 

 sulphuric acid, and set aside for a week : at the expiration of 

 this time, radiating tufts of needles, long and perfectly colourless, 

 filled the xylole, still partly undissolved by the sulphuric acid ; 

 these crystals were collected, placed over sulphuric acid, and 

 enclosed in a glass tube which was afterwards sealed; they were 

 pure sulphoxylolic acid. This substance has a strongly acid 

 reaction; at first its taste is sour, then bitter; it crystallizes 

 well from xylole, is exceedingly soluble in water and in sulphuric 

 acid, deliquesces rapidly in the air, may be fused in vacuo or in 

 xylole vapour without decomposition, but if heated above its 

 fusing-point, acquires a dark colour : the fused acid crystallizes 

 on cooling in fine prisms. A barium salt prepared from this 

 acid gave me 26-93 per cent, of barium ; theory as C 16 H 9 Ba2S0 3 



* I had intended to make a combustion of this base, but was prevented 

 by an accident which occurred to the apparatus in which I was heating the 

 xvlidine in order to determine a second time its boiling-point. I retained, 

 however, a small portion which had distilled twice at a little below 213°, and 

 combined it with sulphuric acid. '8 grm. of this sulphate gave by precipi- 

 tation with chloride of barium -20-17 gi'm. of sulphate of barium, corre- 

 sponding to 28-11 percent, of SO'; the formula C 16 II ,2 N SO' requires 

 28-23 per cent. 



t The same process was adopted in all the other determinations of 

 barium given in the present paper. 



