26 



platino-cyanide of barium at a short distance. In experimenting 

 with this screen, he noticed that certain solid substances, even if 

 interposed directly between the tube and the screen, did not 

 prevent the " fluorescence " of the latter. Rays must, therefore, 

 have penetrated the intervening substance, and to these unknown 

 rays he gave the ordinary scientific denomination of an un- 

 known quantity, and called them "X"' rays. The action of 

 these rays was brought home to the audience in a striking way 

 by Mr. Payne, who, having entirely covered his luminous 

 vacuum tube with some red silk, so that practically no light was 

 emitted, held up the platino cyanide of barium screen, which 

 immediately glowed with its pale green " fluore.scent " light. 

 "Luminous " paint, the fairy lanterns of the glow-worm and the 

 firefly, the myriad sparkling of the tropic seas, and the baleful 

 green of a cat's eyes in the dark, were all, he said, more or less 

 " luminescent " phenomena. 



WEDNESDAY, MARCH 4th, 1900. 



ffib^ning for Microscopes, 



REPORT OF THE COUNCIL 



For the Year ending WEDNESDAY, JUNE 13th, 1900. 



IT will be remembered that last year an invitation was con- 

 veyed from this Society to the Congress of the S.E. Union 

 of Scientific Societies, then meeting at Rochester, to assemble in 

 Brighton this year. This invitation, conveyed by our delegates, 

 Messrs. Slingsby Roberts and E. A. T. Breed, was duly accepted. 

 and the Congress accordingly met here on the 7th, 8th, and 

 9th inst. 



Between 20 and 30 delegates attended from Societies 

 affiliated to the Union, and about 80 tickets were taken by mem- 

 bers of this and other Natural History Societies and strangers. 



At the General Meeting of Delegates held on the 9th inst., 

 a hearty vote of thanks was passed to this Society for the eflbrts 

 made by it for the entertainment of the Congress, eftbrts which, 

 the delegates were pleased to say, had been so far crowned with 



