Compounds of Phosphoric Acid with Aniline. 1 7 



leadj and the precipitate treated with sulphuric acid, gave 

 2*617 grms. of sulphate of lead. 



III. I also determined the acid by precipitating with ace- 

 tate of lead in great excess and boiling for a long time ; the 

 metaphosphate of lead is completely changed into the tribasic 

 salt. This is a very advantageous method of determining 

 metaphosphoric acid. 0-5785 grm. of the substance gave 

 1*3485 grm. of tribasic phosphate of lead. 



These numbers correspond to the following per cents. : — 



I. II. HI. 



Carbon 41*3.3 



Hydrogen .... 4*55 



Phosphoric acid 41*24 40*98 



These analyses lead to the formula 



HO, Ci.H^N, PO5, 



as is seen by the following : — 



12 eqs. Carbon 900*00 



8 ... Hydrogen 100*00 



1 ... Nitrogen 177*01 



1 ... Oxygen 100*00 



1 ... Phosphoric acid . . . 892*28 

 1 ... Metaphosphate of aniline 2169*29 



This salt is analogous to Prof. Graham's metaphosphate of 

 sod^^ NaO, PO5, 



which, according to the experiments of this chemist, likewise 

 becomes viscid on evaporation, and never presents the slightest 

 trace of crystallization. 



The corresponding metaphosphate of ammonia is only 

 known in solution. On evaporation this salt assimilates 1 

 equivalent of water, passing into the common phosphate with 



1 equivalent of ammonia and 2 equivalents of water. 



The experiments which I have described prove that there 

 exist the following series of phosphates of aniline : — 



Phosphates . . .i';?}P'%\^^i^}^'Z?'' 

 * LllOj ^^12 H7 N, 2H0, PO5. 



Pyrophosphate . . HO, CiaH^N, HO, PO5. 



Metaphosphate . . HO, C,2H7N, PO5. 



This series embraces compounds corresponding to all the 

 combinations of soda with phosphoric acid, except the phos- 

 phate with 3 equivalents of soda, and the pyrophosphate with 



2 equivalents of fixed base. 



Phil. Mag. S. 3. Vol. 30. No. 198. Jan. 1847. C 



