which exhibit the phenomena of Fluorescence. 89 



of the earths and metallic oxides — including uranium — with- 

 out being able to observe any other instances of fluorescence ; 

 not even in the case of the lead salt, produced from the basic 

 acetate of lead. This, however, cannot be considered as the 

 way most suited for producing fluorescent comenamates. 



Sulphate of Uranium. — Among the many fluorescent com- 

 pounds of uranium, Professor Stokes does not mention the 

 sulphate. I prepared the salt, and found that the crystals 

 gave a fine greenish dispersion in the more refrangible por- 

 tion of the spectrum, to about the same extent as the nitrate 

 does. A strong aqueous solution was likewise fluorescent, 

 though only to a slight degree. 



Phosphate of Phenyl. — In the Quarterly Journal of the 

 Chemical Society, which appeared last month, there is a paper 

 by Mr Scrugham on " Some New Compounds of Phenyl," in 

 which he describes, among other bodies, a tribasic phosphate. 

 It is an oily liquid at the ordinary temperature, and is said to 

 be fluorescent : " By ordinary daylight, the epipolic rays, 

 which have a fine violet tint, are visible at some distance be- 

 low the surface ; the flame of sulphur does not produce this 

 effect more strongly than the light of the sun." Through the 

 kindness of Professor Williamson, I have had an opportunity 

 of examining a fine specimen of this substance. It was clear, 

 but of a somewhat yellow tint ; and the dispersed colour was, 

 as stated, not blue, but a very beautiful violet. It was so 

 strong as to be perfectly visible by gas-light : it did not ex- 

 hibit itself behind a screen of sulphate of quinine, or ferro- 

 cyanide of iron solution ; and when examined by a ray which 

 had passed through ammoniacal sulphate of copper, it pre- 

 sented an appearance as of a self-luminous, pale violet cloud, 

 entering some distance, perhaps an inch, into the liquid. 



Ottar of Poses. — It is well known that many oils, produced 

 by the dry distillation of organic bodies, exhibit a great dis- 

 position to internal dispersion. It is in most cases difficult 

 to isolate the particular substance to which the property may 

 be owing. Mr Arthur Church has, however, directed my at- 

 tention to one hydrocarbon that displays a remarkable fluo- 

 rescence — the ottar of roses. The blue appearance in this 

 case is similar to that of sulphate of quinine, and is produced 



