JuLY 31, 1902] 
NATURE 
319 
metals for R6ntgen rays have only been determined for rays far 
less penetrating in character than these rays from thorium and 
radium. Benoist has shown that the relative absorption of 
Ro6ntgen rays by matter depends to a large extent on the kind 
of rays employed. ‘‘ Hard” rays give quite different ratios 
from ‘‘soft” rays. For penetrating Rontgen rays the absorp- 
tion of the rays by a gzven wezgh¢ of the elements isa continuous 
and increasing function of their atomic weights. From the 
curve of absorption, given in his paper, the variations of 
absorption with density are much greater for Rontgen rays than 
for the penetrating rays from radio-active substances. 
A very important question arises in discussing the character 
of these penetrating rays. According to the electromagnetic 
theory, developed by J. J. Thomson and Heaviside, the 
apparent mass of an electron increases with the speed, and when 
the velocity of the electron is equal to the velocity of light its 
apparent mass is infinite. An electron moving with the velocity 
of light would be unaffected by a magnetic field. 
It does not seem at all improbable that some of the electrons 
from thorium and radium are travelling with a velocity very 
nearly equal to that of light, for Kaufmann has recently deter- 
mined the velocity of the most penetrating deviable rays from 
radium and found it to be about 95 per cent. of the velocity of 
light. 
The power of these rapidly moving electrons of penetrating 
through solid matter increases very rapidly with the speed. From 
general theoretical considerations of the rapid increase of mass 
with speed, it is to be expected that the penetrating power would 
increase very rapidly as the speed of light was approached. Now 
we have already shown that these penetrating rays have very 
similar properties, as regards absorption and ionisation, to 
rapidly moving electrons. In addition, they possess the proper- 
ties of great penetrative power and of non-deviation by a 
magnetic field, which, according to theory, belong to electrons 
moving with a velocity very nearly equal to that of light. It 
is thus possible that these rays are made up of electrons pro- 
jected with a speed of about 186,000 miles per second. 
An interesting speculation arises from the experimental ob- 
servation that the excited radiations from bodies include these 
very penetrating rays. Elster and Geitel have recently shown 
that excited radio-activity can be produced from the atmosphere 
by exposing a negatively charged wire in the open air. This 
excited activity is very similar in properties to that produced by 
thorium and radium. Since the earth is negative with regard 
to the upper atmosphere, the surface of the earth is itself made 
radioactive. From the nature of the phenomenon, it necessarily 
follows that, not only the surface of the earth, but also the whole 
interior surface of buildings is covered with an invisible deposit 
of radioactive matter. From the close similarity in the nature 
of this excited activity from the air with that from radio-active 
bodies, it is not improbable that the excited radiations from the 
air include also some of the penetrating rays. If this is the case, 
our bodies must be continually subject in a small degree to 
something very like the Rontgen ray treatment, which is now 
so popular in medical circles. It would also follow that the 
“* spontaneous ”’ ionisation of air, observed in closed vessels by 
Elster and Geitel and C. T. R. Wilson, may be due, in part at 
least, to the presence of these rays, which so readily pass through 
the walls of the containing vessels. E. RUTHERFORD. 
McGill University, Montreal, July 6. 
The Future of the Victoria University. 
THE interesting contribution on the subject of the Victoria 
University which Prof. Schuster has made to your columns 
(July 19, p. 252) invites a few words of reply from one who 
does not regard the possible disruption of the University with 
the same complacency. 
It may be unknown to many readers of NATURE that the 
proposals which would disband the University arose in such a 
way as to preclude that close and careful deliberation on the 
future of the University and its colleges which would have re- 
sulted in a peaceful maintenance of the status guo or in a 
harmonious process of separation. We should otherwise have 
been saved from the unfortunate situation in which the University 
is now placed, when one of the colleges and its county is left 
standing alone for the maintenance of the University. 
I refer to this because it might be, supposed that the existing 
state of affairs was the outcome of something like a quarrel. 
There has been no quarrel ; the three colleges of the Victoria 
NO. 1709, VOL. 66] 
University have worked together with a degree of smoothness 
and good feeling that might seem hardly possible to those who 
know the strong local sentiment of the two counties and the 
three towns. There have indeed been many controverted ques- 
tions in the University history, but the lines of party have, I 
think, been usually independent of the colleges. 
The question of disruption having been raised in such a way 
that the University itself could not consider it by means of an 
unpledged tribunal, the Yorkshire College, believing the move- 
ment to be detrimental to the interests of education, desired 
that there should be a Government inquiry by means of a Royal 
Commission or other body of high authority. This proposal has 
not been accepted by the majority of the University Court, and 
as the matter rests now we have the application of Liverpool 
for a university formally opposed by Yorkshire and formally 
approved by Owens College, subject to Manchester being also 
allowed an independent university. 
I have no wish to enter here upon the general question of the 
relative merits of single college and federal universities, but 
I think there is something to be said on another question of 
more immediate practical importance, and that is, whether an 
action so grave as the disestablishment of a university should 
not be the subject of a strict and impartial public inquiry. 
It is true, no doubt, that the Privy Council may be trusted 
to give a careful and impartial consideration to the question 
before it, but in the ordinary course of things that would not in- 
volve a public inguiry, and the grounds on which any decision 
was reached would not be made known. 
I believe that the future of the Victoria University isa question 
not affecting that University alone. It raises the much greater 
issue of the future of university organisation in England, and 
it seems to me to be of the first importance that the real grounds, 
if there are any, for the disruption of the federal Victoria Uni- 
versity should be clearly set forth in evidence and endorsed by 
competent authority. 
Prof. Schuster says that ‘‘the Victoria University is now 
practically an examining body, which unites all disadvantages.” 
That is just the sort of statement I wish to see sifted by an 
impartial tribunal. Many of us would say that such a statement 
cannot be serious ; it seems so exaggerated. 
It is proposed to dissolve a great educational corporation 
which after twenty-three years of hard work has acquired real 
momentum and has come to be recognised as a factor in 
educational affairs not inconsiderable when compared even with 
the older universities. I am one of those who believe that a 
factor of this particular kind has been and is one of the most 
urgent needs of our time. I believe also that the defects of the 
Victoria University, which are undoubted, might be largely 
rectified by a less drastic process than disruption, and that with 
a revised constitution the University might continue to exist 
with greater freedom and ease for its constituent colleges and 
with undiminished effect in their collective action as an 
enlightened ‘‘modern” force on English education. 
Surely at least the question is worthy of the most careful 
consideration and is one that calls for an open inquiry. 
In conclusion, I deplore the haste which has been made by 
advocates of disruption to convince the public of the defects of 
a University which after all may be obliged to continue its 
existence. ARTHUR SMITHELLS. 
July 14. 
IN writing about the future of the Victoria University in a 
scientific journal I was anxious to avoid all questions which are 
immaterial to the main point. Prof. Smithells’s letter deals 
mainly with side issues. The lines of cleavage at our board 
meetings interest no one but ourselves, and it does not matter 
now whether Liverpool might or might not have proceeded ina 
more academic manner. 
The position at present is this:—The two senior colleges, 
representing about three-quarters of the University, believe that 
independent universities will in future be able to carry out their 
educational work better than the present federation. Prof. 
Smithells thinks that we ought to have accepted the proposal of 
the Yorkshire College to have the whole question referred to a 
Royal Commission. But surely the only course likely to be 
followed by men who know their own minds is to ask for what 
they want; at any rate, it is the only way to getit. Itis 
fortunate, however, that Prof. Smithells’s predilection in favour 
of a federal university may yet be satisfied. Yorkshire is quite 
large enough to supply the material for a federation, and as an 
