562 
NATURE 
imi 22) coms 

Such facts, while not explicable on the ground that 
the inhibition is due merely to a trace of alkali derived 
from the glass, form a confirmation of the theoretical 
considerations put forward in our paper. 
July 7. W. CRAMER. 

Origin of « Mathematical Symbol for Variation. 
As a contribution to the history of algebraic nota- 
tion it may be worth while to point out that the symbol 
ec for variation was introduced by William Emerson. 
In his ‘‘ Doctrine of Fluxions,” third edition, London, 
1768 (first edition, 1749), he says on p. 4:—*To the 
common Algebraic Characters already receiv’d I add 
this «, which signifies a general Proportion; thus, 

’ 
Ac = signifies that A is in a constant Ratio to 
that is (if a, b, c, d be other Values of these Quan- 
ae BC bc 
tit AN = 3 . 
ities) D d 
tion is to be understood.” FLorran Cajort. 
1 Gordon Street, Gordon Square, ‘London, W.C. 
uae and thus every general Propor- 

SCIENCE AND MUNITIONS OF WAR. 
\\JE give in another column the names of the 
members of the Inventions Board which 
is assisting the Admiralty in the co-ordination and 
encouragement of scientific effort in relation to 
the requirements of the Naval Service. The 
Central Committee and the Panel of Consultants 
form as strong a body of expert opinion as it 
would be possible to bring together; and their 
judgment upon scientific matters submitted to 
them may be accepted with confidence. Sug- 
gestions and inventions sent to the Admiralty 
will, if they relate to naval matters, first be con- 
sidered by officials of the existing staff, and any 
promising ideas or devices will be passed on to 
the Central Committee, consisting of Lord Fisher, 
Sir J. J. Thomson, Sir C. A. Parsons, and Dr. 
G. T. Beilby. This committee, when necessary 
or desirable, will refer particular points to 
members of the panel of consultants, which in- 
cludes leading workers in chemistry, physics, 
metallurgy, and various branches of engineering 
science. The president of the Royal Society is 
one of the consultants, and with one exception all 
the other advisers are fellows of the society, 
which is thus giving of its best to the service of 
the country. 
Since the early days of the war the Royal 
Society has been in close touch with the naval 
and military authorities with regard to scientific 
problems presenting themselves in the course of 
the operations. In the autumn the Council set 
up an organisation which has been expanded in 
various directions to meet the continually increas- 
ing requirements of the Government for scientific 
assistance. It consisted essentially of a general 
controlling committee, which was at first 
appointed ad hoc, but is now the Council itself; 
and sectional committees, each of which repre- 
sents one of the several branches of science con- 
cerned, namely chemistry, engineering, physics, 
and physiology. Each committee has _ been 
placed by the council in charge of a chairman of 
acknowledged eminence. The Governmental de- 
NO. 2386, VOL. 95] 


partments concerned have nominated special repre- 
sentatives who sit as members of the sectional 
committees, and through them and the committees’ 
own officers confidential relations have been estab- 
lished with those departments. The committees 
also are in touch with the scientific institutions 
and manufacturing centres throughout the 
country. These committees as working bodies 
are necessarily limited in size, having regard to 
the very confidential nature of the subjects sub- 
mitted to them; but they avail themselves largely, 
as circumstances require, of the services of in- 
vestigators outside their own membership. 
The value of the work thus accomplished was 
publicly recognised by the Prime Minister lately 
in his remarks in the House of Commons. But 
though the Government has acknowledged that 
scientific men have rendered valuable assistance 
in connection with problems arising out of the 
war, no definite scheme seems yet to exist for 
the organisation of our scientific forces into a 
composite body. The Chemical Society, as we 
announced on July 8, has taken steps of its own 
accord to form a consultative council upon which 
kindred societies such as the Institute of 
Chemistry, the Society of Chemical Industry, the 
Society of Public Analysts, the Pharmaceutical 
Society, and the Institution of Mining and Metal- 
lurgy will be represented. Scientific and industrial 
knowledge and interests are thus intimately asso- 
ciated, as they should be, but the relation of this 
group of chemical societies to the Physical Society, 
which has also formed a committee to consider 
suggestions and inventions, or to the war coni- 
mittees of the Royal Society, does not appear to — 
have been settled. Unless there is close co-opera-— 
tion between the committees of the various 
scientific societies it is dificult to see how over- 
lapping will be prevented or how combined expert 
knowledge can be concentrated upon physical, 
chemical, and engineering problems requiring 
early and practical solution. 
In addition to appointing committees to consider 
suggestions or inventions, the Royal, Chemical, — 
and Physical Societies have taken steps to obtain — 
registers of their fellows classified according to ~ 
special knowledge and to scientific services which ~ 
the fellows are willing, as well as specially quali-— 
fied, to perform. The idea in each case is to 
secure co-operation among the fellows of the par- 
ticular societies, and to examine by means of — 
committees any promising suggestions relating 
to munitions of war or kindred subjects. No one © 
knows precisely what will be done with the 
registers when they have been completed. Each — 
society seems to be compiling its list indepen-_ 
dently and without any clear view of the use 
which will be made of the experts’ services which 
will become available by the response to its — 
circular. No scheme has yet been put forward 
by which definite national duties will be assigned — 
to the hundreds of scientific men who are enrolling 
themselves on the registers of their respective — 
societies. 
The case is different with men who - 
ee 
