1896.] Light from Polished Speculum-Metal Mirrors. 331 



A, Vacuum tubes. 



BB', Lead plate, 18 in. x 12 in. | in. thick. 



C, Hole 2 in. diameter. Pipes 2 in. diameter x | in. 



D, Speculum -metal mirrors. 



E, Zinc box, 4 in. x 4 in., 1 in. deep. 



F, Aluminium window. 

 Gr, Objects. 



H, Black cardboard. 



I, Photographic plate. 



Some experiments I have carried out in my laboratory at Blyths- 

 wood induce me to believe that the X rays can be reflected. 

 vol. lix. 2 A 



