72 
RESULTS OF PHYSICAL AND CHEMICAL INVESTIGATIONS. 
Upon submitting an absolutely pure specimen of toluidine, however, to the agents already 
named, under the most varied circumstances, no trace of colour could be obtained. 
A happy experiment served to clear away the obscurity which was seemingly thicken¬ 
ing round this question. 
Upon treating a mixture of pure aniline and pure toluidine with arsenic acid or the 
other oxidizing agents, an abundance of magnificent colour was instantly obtained. It 
thus became manifest that the production of magenta depends upon the co-operation 
of both bases. Dr. Hofmann is still engaged in working out the consequences of this 
discovery. 
On some Metallic Combinations of Aniline. —M. Hugo Schiff has presented to 
the French Academy an account of a series of compounds, formed by the union of ani¬ 
line with metallic salts, which tend to thrown an additional light on the formation of 
magenta or rosaniline. Representing aniline (C 12 H-N) as ammonia, in which one atom 
of hydrogen is replaced by phenyl— 
f C 12 H 5 
N < H 
C H 
these compounds, according to M. Schiff, are salts of a series of metal-anilines ; a second 
atom of hydrogen in the ammonia being replaced by a metal. Thus, aniline combined 
with a salt of zinc forms a salt of zincanile , having the composition— 
C 12 H 5 
C 12 H 0 ZnN = N " 
The hydrochlorate of zincanile (C 12 H 6 ZnN,HCl) crystallizes in oblique rhomboidal 
prisms, free from water, and soluble in water and alcohol, especially when heated. By a 
prolonged boiling of these solutions the salt is decomposed into aniline and chloride of 
zinc. It combines with bichloride of platinum, forming granular crystals. The hydro- 
bromate and the hydriodate resemble the hydrochlorate. 
The sulphate (C 12 H 7 ZnN, S0 4 ) is more soluble than the preceding salts, which may be 
prepared from it by double decomposition. Aniline is added to a solution of sulphate of 
zinc, diluted with water to such an extent as to keep everything in solution ; then, on 
adding a concentrated solution of chloride, bromide, or iodide of potassium, colourless 
crystals of the corresponding salts separate out. 
The salts of cadmianile 
C 12 H 6 CdN=N 
c 12 h 5 
are obtained in the same manner as the salts of zincanile, and possess the same chemi¬ 
cal and physical properties. Neither the one nor the other are decomposed by dilute 
acids in the cold, and even at the boiling temperature decomposition proceeds very 
slowly. 
The cupranile 
CC 12 H 5 
C 1 oH 6 CuN=N-5 Cu 
( H 
forms compounds very little soluble in cold water, and which are decomposed easily by 
luke-warm water. 
Tin furnishes two aniline compounds:— Stannosanile , 
C :2 H 6 SnN = N 
c 12 h 5 
Sn 
H 
a monoatomic (Sn=58) base, corresponding to stannous compounds ; and stannicanile , 
2 C 12 H 5 
C„ 4 H 12 Sn ,, N 2 = N 2 < Sn" 
(2H 
a diatomic base, corresponding to stannic compounds. 
The hydrochlorate of stannosanile (C 12 H c SnN,HCl) is obtained by mixing equal equi- 
