648 SCIENTIFIC EECORD FOE 1885. 



To this note in the sealed packet the French chemist added the fol- 

 lowing : "I have not yet finished the very long work undertaken in the 

 hope of determining the nature of the above-described phosphorescent 

 spectrum. This spectrum is now recognized as identical with that as- 

 cribed to pure yttria by Mr. Crookes, and which this savant obtained 

 under experimental conditions very dilierent from mine. Nevertheless, 

 my latest observations lead to the conclusion that yttria is not the 

 cause of the si)ectrura bands observed. In my fractionations the phos- 

 phorescence spectrum regularly gets weaker as I advance towards the 

 yttria end. With almost pure yttria the phosphorescence bands show 

 themselves faintly or not at all, while they are brilliant with the earths 

 which do not give, by the direct spark, the rays of yttrium to an ap- 

 preciable extent. The prodigious sensitiveness of Mr. Crookes' reac- 

 tion, which detects a millionth part of his purified yttria, makes very 

 singular this divergence which I am obliged to point out between the 

 conclusiyns of the eminent English chemist and myself" - - - "I 

 should acknowledge here that Mr. Crookes was the first to see the 

 phosphorescence spectrum of samarium." {Comptes rendus, C, 1437, 

 and Chem. N'eics, lii, 4.) 



Quantitative Determination of Lithium by the Spectroscope. — L. Bell has 

 found the following method gives good results : A standard solution was 

 made from lithium carbonate converted to the chloride, containing 

 .0265™em of LhO per cubic centimeter. Of this 10'=« were taken, diluted 

 till the spectral line was just on the point of vanishing and the vol- 

 ume noted. Then the solution to be estimated was diluted to the same 

 point and its volume compared with that of the standard, when a sim- 

 ple proportion gave the amount of Li20 present. A very small loop of 

 platinum wire should be used and applied to the same part of the Bun- 

 sen flame. The method is applicable to the analysis of lithium miner- 

 als, and examples are given. The method is useful also in case of 

 thallium and sucli other elements as give distinct lines in the spectro- 

 scope. {Am. Chem. t/., Vii, 35.) 



Action of Light on Iodoform in Solution. — E. Eabini has observed that 

 a solution of iodoform in benzine becomes bright red when exposed to di- 

 rect sunlight for ten to twenty minutes, whereas in the dark it remains 

 colorless. If a solution prepared in the dark is suddenly exposed to 

 the rays of the sun it immediately turns to a splendid red color, and 

 iodine is precipitared. Further experiments with solutions of iodoform 

 in ether and in oils shows it to be very sensitive to light, being thereby 

 reduced. {Pharmaceutische Post.) 



, On the Action of Light in Chemical Reactions (by D. Amato). — The 

 author, in studying the action of light and of heat in chemical re- 

 actions, has obtained results of great interest ; he shows that many of 

 the decompositions and combinations attributed to the action of light 



