RONTGEN RAYS. 
w 
BY 
W. WEBSTER, Esq., f.c.s. 
(A Lecture delivered at the Royal Artillery Institution, Woolwich, Thursday , 12th Nov., 1896.) 
Colonel C. C. Trench, Director Artillery College, in the Chair. 
Colonel Trench, Ladies and Gentlemen—I start with a consider¬ 
able amount of diffidence in approaching a subject of this description, 
because there has been so much written in the public press for and 
against it, that it is difficult to tell you anything new ; in fact, there is 
nothing new to tell, as the process is merely an evolution of a series of 
discoveries made by eminent men. 
We owe to Electricity some of the greatest benefits mankind has ever 
enjoyed : Telegraphy, Telephonic Communication, Lighting, etc ; also 
in Surgery, electric Cautery and Electrolysis ; and it now seems 
that still greater benefits are to be received in this direction by means 
of the Rontgen or X Rays. 
We start in ignorance, for although electricity can be explained in a 
highly mathematical manner, it is by no means satisfactory ; the 
explanation usually given, in a popular form, is that there exists a 
subtle fluid which acts by repulsion on its own particles and pervades 
all matter. By friction certain bodies acquire an additional quantity, 
and are said to be positively electrified ; others by friction lose a 
portion, and are said to be negatively electrified ; the two, when com¬ 
bined, neutralise one another, and are then supposed to be in the 
natural state generally called “ Static.” 
Electricities of the same name repel one another, and electricities of 
opposite kinds attract one another ; but beyond the fact that we know 
the properties of this mysterious Ether or Fluid and can use it for Heat, 
Light, Chemical Action or Power, we are absolutely ignorant of what it 
is—we are dealing with an unknown quantity. 
5. VOL. XXIV. 
27 
