RONTGKEN RAYS UP-TO-DATE. 
547 
phosphorescent screen it was detected and a mark made on the arm; 
before the close of the lecture the piece of metal which had been cut 
out was sent from the Arsenal and exhibited on a plate to the audience. 
Special reference was made to the excellent X Ray work carried out at 
the Miller and St. Thomas's Hospitals. 
Lantern slides were then thrown on a screen showing the advance 
made in reducing the time of exposure, and unavoidable errors in 
surgery due to the non-use of X Ray apparatus. 
The lecture concluded with hearty thanks tendered by Colonel H. 
S. S. Watkin, c.b., the chairman, in the name of all present. 
After the lecture Mr. Webster very kindly gave individual members 
of the audience opportunities of inspecting his instruments and 
apparatus and of testing the extraordinary state of transparency 
produced by tubes treated as recommended by him in the lecture, 
acting through the medium of a phosphorescent screen. 
