M. Kraut on Toluric Acid. 193 



really occupies the same place as the chlorine in chloride of ben- 

 zoyle, C^'^H^O^ CI, this latter, or some other haloid compound 

 of benzoyle, ought, by an appropriate action of hydrogen in the 

 nascent state, to be converted into hydruret of benzoyle, 



C^4H5 0^C1 + 2H = Ci^H^O^H + HCl. 



Chloride of benzoyle. Hydruret of benzoyle. 



The ready decomposability of chloride of benzoyle renders it un- 

 fitted for this reaction, but the change takes place with cyanide 

 of benzoyle ; for when it is treated with hydrochloric acid, and 

 granulated zinc added, decompositiou of the cyanide takes place, 

 the odour of hydrocyanic acid is evolved, and the mass contains 

 a large quantity of hydruret of benzoyle, which is separable by 

 distillation. 



The same change occurs when cyanide of benzoyle is treated 

 with mercury and hydrochloric acid. 



Kraut* found that toluylic acid, when taken into the system, 

 gives rise to the formation of a new acid. The toluylic acid was 

 taken in doses of several grammes at a time without any percept- 

 ible efi'ect on the organism ; the urine had afterwards a distinctly 

 acid reaction. The new acid, which Kraut names toluric acid, is 

 obtained from the urine by the methods used for extracting hip- 

 puric acid from that source. 



Toluric acid crystallizes in the rhombic system in hard lus- 

 trous crystals. It is easily soluble in alcohol and in boiling 

 water, from which it crystallizes on cooling. It decomposes the 

 earthy carbonates, forming with the bases crystalline salts. The 

 formula of the acid is C^o Hi^ NO^ and of its salts C^o W N0«. 

 Treated with hydrochloric acid, it undergoes a change entirely 

 analogous to hippuric acid under the same circumstances, being 

 converted into toluylic acid and alcohol. 



Toluylic acid undergoes, hence, in passing through the organ- 

 ism, a similar change to benzoic acid ; with loss of water it assi- 

 milates the elements of glycocoU : thus — 



C14 H6 04 + C^ IP NO'^-2HO = Ci8 H^ NO^. 



Benzoic acid. GlycocoU. Hippuric acid. 



Ci^H^ 0^ + 04 HSNO4-.2HO = C20HiiNO^". 



Toluylic acid. GlycocoU. Toluric acid. 



Kraut confirms the statement of Hofmann, that cuminic acid 

 passes through the body unchanged. 



Professor Schmidt f of Dorpat has investigated the boracic 

 acid fumaroles of Monte Cerboli in Tuscany. In order to check 



* Liebig's Annalen, June, p. 360. f Ibid. p. 273. 



Phil. Mag. S. 4. Vol. 12. No. 78. Sept. 1856. O 



