26 Mr. Noad on the Action of Nitric Acid on Cymol. 



which it is very sparingly soluble ; it is then dissolved in hot 

 alcohol, boiled for a few minutes with animal charcoal, and 

 filtered ; by spontaneous evaporation the new acid crystal- 

 lizes out in beautiful rhombic prisms of a pale yellow colour. 



Composition of Nitrotoluylic Acid. 



The powdered crystals by combustion with oxide of copper 

 yielded the following numbers : — 



I. O'o30 grm. gave 0*640 carbonic acid and 0*1205 water. 



II. 0*382 grm. gave 0*7396 carbonic acid and 0*136 water. 



III. 0*4145 grm. gave 0*806 carbonic acid and 0*152 water. 



IV. The nitrogen was determined by Dumas' method in 

 an atmosphere of carbonic acid. The particulars of the ex- 

 periment are as follows : — 



0*600 grm. gave 41*5 cubic cent, of moist nitrogen. Ba- 

 rometer 0'"*7973 ; Thermometer 18°*5 C. 



These numerical results correspond with the following per 

 cents. : — 



I. II. III. IV. 



Carbon . , 52*89 52*80 53*03 

 Hydrogen . 4*06 3*95 4'07 



Nitrogen ... ... 79*6 



and lead to the formula HO, Cig-< -^^^^ > O3, as the following 



comparison of the calculated numbers with the mean of 

 analysis shows : — 



Theory. Mean of expt. 



16 eqs. Carbon .... 96 53*03 52*90 



7 ... Hydrogen ... 7 3*86 4*00 

 1 ... Nitrogen ... 14 7*74 7*96 



8 ... Oxygen ... 64 

 1 ... Nitrotoluylic acid 181 



By the following analyses of some of the salts of this acid 

 the above formula is fully confirmed, and the atomic weight 

 of the acid proved. 



Nitrotoluylate of Baryta. — This salt was formed by adding 

 chloride of barium to a neutral solution of nitrotoluylate of 

 ammonia. A white curdy precipitate was determined, soluble 

 to a considerable extent in boiling water, out of which it cry- 

 stallized on cooling in beautiful stellated tufts, having a 

 shining appearance when dry : after two or three recrystal- 

 lizations it was submitted to analysis, and yielded the follow- 

 ing results : — 



0*738 grm. gave by ignition 0*290 grm. of carbonate of 



