Mr. J. Parnell on a new Fluorescent Substance. 137 



crude mass obtained by the process above mentioned, when 

 pounded, mixed with water, and washed with ether, gives an 

 ethereal solution which in a concentrated state exhibits a fluo- 

 rescence which it is believed has never been surpassed by any 

 known body*. By this means, however, the powdered mass is 

 apt to cake together, so that it is difficult to extract all the sub- 

 stance in question, which, to avoid periphrasis, it is proposed tem- 

 porarily to call Fluoraniline. A better method appears to be to 

 dissolve the crude mass in dilute hydrochloric acid, to add am- 

 monia in excess, and then to wash out with ether. The ethereal 

 solution thus obtained must be repeatedly washed with water 

 until the washings cease to acquire a pink colour. Thus purified it 

 has a greenish-yellow colour and exhibits a green fluorescence. 

 When evaporated to dryness spontaneously, the residue consists of 

 two amorphous substances, one red and the other orange, the fluo- 

 rescence being due apparently to the latter. The author has not 

 succeeded at present in perfectly eliminating the red substance, 

 although it may be got rid of to a great extent by washing the 

 ethereal solution with dilute hydrochloric acid (which will extract 

 the whole of the crude fluoraniline), reducing with zinc, adding 

 ammonia in excess, extracting with ether, and, if necessary, re- 

 peating the process. From a specimen of aniline-red prepared by 

 Messrs. Maule and Nicholson, but by what process the author has 

 been unable to learn, as much as 10 per cent, of crude fluoraniline 

 has been extracted. When an ethereal solution of fluoraniline 

 is evaporated spontaneously till all the ether has gone, and then 

 heated on a water-bath to drive off the small quantity of residual 

 water, a strong smell of peppermint is evolved. As the heat is 

 increased, a substance is volatilized which condenses as a dark 

 brown matter insoluble in ether, and as still further heat is ap- 

 plied hydrocyanic acid is evolved. 



Fluoraniline is almost insoluble in water when cold, but 

 slightly soluble in hot water, being precipitated as the water 

 cools. It is soluble in dilute hydrochloric, nitric (thus distin- 

 guishing it from chrysaniline), sulphuric, and acetic acids, giving 

 fluorescent solutions, is not affected by sulphide of ammonium, 

 and but slightly by hypochlorite of calcium. The alcoholic so- 

 lution is of a much darker colour than the ethereal,. and not so 

 fluorescent ; but alcohol added to a solution of fluoraniline in hy- 

 drochloric acid increases its fluorescence ; it was, indeed, by add- 

 ing that acid to an alcoholic solution of aniline-red that atten- 

 tion was first drawn to this subject. The fluorescence of this 

 substance is most remarkable. When a beam of sunlight made 



* The author has not had an opportunity of examining a new substance 

 exhibiting a green fluorescence, which has recently been obtained by M. 

 Wurtz by a totally different process. 



