January 28, 1904] 
NALTORE 
293 
LEDTERS TO THE EDITOR. 
[The Editor does not hold himself responsible for opinions 
expressed by his correspondents. Neither can he undertake 
to return, or to correspond with the writers of, rejected 
manuscripts intended for this or any other part of NATURE. | 
No notice is taken of anonymous communications.] 
The Royal Society. 
Ar the special meeting of the Royal Society held on 
January 21, when the constitution and functions of the 
sectional committees were under consideration, the opinion 
was expressed by more than one speaker that the usefulness 
of the society in encouraging and advancing scientific work | 
is not what it might be; but no very definite suggestions 
were made with a view to its improvement. 
It seemed to me that the functions of these sectional com- 
mittees had a good deal to do with the lack of scientific 
enterprise which we observe in the Royal Society, and that 
they might with advantage be done away with. 
As many of the fellows had left the meeting before I 
spoke, and as everything that affects the efficiency of the 
Royal Society concerns the public, I crave the hospitality 
of the columns of Nature to develop as shortly as possible 
my views on this matter. 
The main function of the sectional committees is to refer 
papers received by the society from fellows, to some other 
fellow or fellows of the society to be certified that they are 
or are not fit to be accepted and published by the society. 
It is well known that the fellows of the society are de facto 
chosen by the council after rigid scrutiny and the most 
careful inquiry, and the only object of this scrutiny and 
inquiry is to satisfy the council that the candidate whom 
it recommends is a man of eminence in his own science, and 
that the work which he is likely to do will be a credit to 
the society. So convinced is the society of the thorough- 
ness and impartiality with which the council discharges this | 
duty that the confirmation of its selection by election has 
come to be a pure formality. This being so, it cannot fail 
to surprise the newly elected fellow, when he proceeds to 
justify his election by doing work and communicating the 
results of it to the society, to find that he is now in no 
better position than he was before he was elected. His | 
work is referred in the same way as that of any outsider. 
His recent selection by the council is ignored by that body 
or is regarded as having no weight, and it treats him, 
scientifically, as a perfect stranger. 
Furthermore, this reference, which amounts to neither 
mere nor less than a secret revision of the title of the fellow 
to the privileges of the society, is repeated on every occasion 
when he comes under the notice of the society by offering 
it work. So long as he is content to be a passive fellow, or 
at least an inactive one, he is spared this injustice and 
indignity. It is no wonder then that the fellowship of the 
Royal Society has come to be looked on as an invitation 
to repose rather than as an incentive to work. 
How different is the state of things which we observe 
in the parallel society in France, the Academy of Sciences. 
Its constitution is thoroughly democratic, and all its pro- 
ceedings are inspired by enlightened self-respect. But we 
need only contemplate the work which it puts through in 
the year and compare it with what is turned out by the 
Royal Society to see that there is something for us to learn 
by its study. 
First and foremost the academy meets fifty-two times in 
the year, namely, on every Monday, with the exception of 
Easter Monday and Whit Monday, and then it meets on the 
following Tuesdays. By the time-table of the current year 
the Royal Society is to meet twenty times. ; 
Papers by members, or communicated by members of the 
academy, are not obliged to be sent in before the meeting. 
The agenda of the meeting is compiled at the meeting, each 
member who has a paper to communicate giving notice of 
it to the secretary on his arrival in the room, and the 
papers are taken strictly in the order of their intimation. 
If the paper communicated by the member is to be pub- 
lished in the Comptes rendus of the sitting, it has to be 
handed in to the secretary at the sitting; the corrected | 
proof has to be returned to the printer on the Wednesday | 
evening, and it is then published without fail on the Sunday. 
NO. 1787, VOL. 69] 
The communication, reading, and publication of a paper pre- 
sented to the academy is therefore an affair of the inside 
of a week, and it is a certainty. This promptitude in the 
putting through of work is due to the fundamental fact 
| that when a man is elected a member of the academy he 
entérs at once into the full enjoyment of all its privileges, 
and one of the chief of these is the complete confidence of 
all his fellow-members. When he communicates a paper, 
whether it be by himself or by someone not a member of 
the academy, it is accepted without question. The only 
limitation in the privileges of members is with regard to 
the space that they are entitled to claim in the Comptes 
rvendus. A paper by a member or foreign associate of the 
academy may fill six pages per number, and his communi- 
cations in the year may fill fifty pages in all, and this as 
a matter of right. 
It is unnecessary to occupy more space in order to show 
what a powerful engine the Academy of Sciences is in the 
production and encouragement of work, or to indicate how 
easily the Royal Society may successfully rival it. Let 
every fellow of the society, whether he be on the council or 
not, have complete confidence in his fellow-fellows and give 
practical effect to it, and the thing is done. The rest will 
follow of itself. J. Y. BucHanan. 
January 23. 
The Radiation from an Electron describing a Circular 
Orbit. 
Tue complete formula for the radiation may be useful to 
some of those who are now indulging in atomic specula- 
tions. It is derived from the general formula I gave a year 
ago in Nature (October 30, 1902), expressing the electro- 
magnetic field everywhere due to an electron moving any- 
how. Put in the special value of R required, which is a 
matter of elementary geometry, and the result is the com- 
plete finite formula. But only the part depending on R-* 
is required for the radiation; and, in fact, we only want 
the r—-? term (if r=distance from the centre of the orbit), 
if the ratio of the radius of the orbit to the distance is. 
insensible, and that, of course, is quite easy, on account of 
the extreme smallness of electronic orbits. The magnetic 
force is given by 
Qun . 
Hy,= <— 2° cos @ cos ¢), 
4nrv 
(1) 
subject to 
gy=%, +B cos $= — nt +nr/v. (4) 
There is no limitation upon the size of w/v, save that it 
must be less than 1. But there is a limitation regarding 
the acceleration. If the change in the acceleration is 
sensible in the time taken by light to traverse the diameter 
of the electron, it will sensibly alter the results. The size 
of the electron itself will then have to be considered. But 
this is very extreme. To explain the symbols: the 
(surface) charge is Q moving at speed u and angular speed 
n in a circle in the plane perpendicular to the axis from 
which @ is measured. It revolves positively round this 
axis, and its position when t=o is =o. Also, r, 0, @ are 
the usual spherical coordinates of the point of observation, 
and Hy. Hs are the @ and @ components of the magnetic 
force at that point at the moment ¢. The coefficient a® 
shows the Doppler effect on H. The difference between 9, 
and », must be noted. 
It will be readily seen what an important part the Doppler 
effect plays if, as has been sometimes assumed, sub- 
atomic motions of electrons involve values of w which are 
not insensible fractions of v. For instance, in the plane of 
the orbit, H@=o, and 
— Quan sin g,-u/o _ 
4 4mrv [1 —(z/v) sin >, }° 
(5) 
