188 
NATURE 
Dynamo Circuits Contractions 
Example :— 
ie eee a 
a ae 
a ; 
or D fer Dynamo. 
T+  ,, Terminal positive. 
T-— _ ,, Terminal negative. 
E.M. ,, Electro-magnet. 
or F.M. ,, Field Magnet. 
c.p. », candle-power of a lamp. 
A.M. ,, Ampere meter. 
V.M. ,, Volt-meter. 
S.W.G.,, Standard wire gauge. 
For use in Formule 
Rz R,, Re ,, Resistance of armature, magnets, and ex- 
ternal circuit respectively. 
Current in armature, magnets, and external 
circuit respectively. 
L; ,, coefficient of self-induction. 
L,, ,, coefficient of mutual induction. 
In the above notation the first letter of the most important 
words has been used wherever it was found practicable to do so, 
and the recurrence of the same letter under similar circumstances 
avoided as much as possible. In cases where no ambiguity can 
occur, such as H for the heat in Joules, and H for the horizontai 
intensity of the terrestrial magnetism ; for metre, and m for 
magnetic strength of pole; V for velocity, and v for volts, it 
will be observed that the same letters appear in each case. 
M. Hospitalier, the Secretary for the French Committee on 
this subject, came over from Paris specially to take part in the 
ceecussien; and related what had already been done by him in 
aris. 
Prof. Forbes, Mr. John Munro, Prof. Ayrton, Dr. Fleming, 
Ca Cy Ce ,, 
Prof. Hughes, Prof. Silvanus Thompson, and others took part | 
in the discussion, and generally agreed that a uniform system 
was much required. The paper, they said, had givena very fair 
start to this being accomplished. 
The author replied that he was glad the Society had agreed 
so readily to form a thoroughly representative committee, and 
hoped that their work would be not only speedily accomplished 
but satisfactory to all concerned. 
THE JUBILEE OF THE STATISTICAL 
SOCIETY 
THE Statistical Society has been holding a series of meetings 
: during the present week in celebration of the jubilee of 
its foundation. The meeting is really an International Congress 
of Statistics, some of the most eminent foreign statisticians being 
present as the guests of the Society ; among others Sig. Bodio, 
| 
of Rome; MM. Keleti, KGrési, and Prof. Neumann-Spollart, | 
of Buda-Pesth ; Prof. Levasseur and M. de Foville, of Paris ; 
Gen. F, A. Walker, of the United States, Gen. Liagre, and 
others. The meetings have been held in the theatre of London 
University, and several subjects of much statistical importance 
have been introduced for discussion. One of them was the 
claim of statistics to be considered as a science, discussed at 
some length in the address of the President, Sir Rawson W. 
Rawson. Statistics, as usually treated in this country, little 
more than the mere calculating of numbers, is a mere mechani- 
cal operation ; but which, treated as some of the most eminent 
statists have treated it, as dealing with the structure of human 
society, then it certainly becomes amenable to scientific methods. 
Sir Rawson Rawson referred further to the want of organisation in 
the collection and publication of official statistics in this country, 
and rightly advocated reform in thisrespect. Among the other 
papers read on Monday were—a sketch of the history of the 
Society, by Dr. F. J. Mouat; ‘‘ Statistical Developments, with 
special reference to Statistics as a Science,” by Dr. W. A. Guy, 
F.R.S. ; and on ‘Statistics and their Enemies,” by M. de 
Foville. One of the principal papers on Tuesday was by Mr. 
R. Giffen, on ‘‘ Some General Uses of Statistical Knowledge,”’ 
[Fune 25, 1885 
in which, among other things, he referred to the rapid increase of 
the population of Europe during the last century as compared 
with the increase in China and other Asiatic countries (except 
India) and in Africa. Should the present rate of European in- 
crease continue, the population of our continent in another 
century will be 1000 millions, whilst that of the United States 
would be 800 millions. Mr, Giffen maintained that the increase 
in Europe had been accompanied by a corresponding increase in 
the means of subsistence and improvement in the position of all 
classes. 
Mr. J. S. Jeans read a paper ‘‘ On Uniformity of Statistics.” 
He held the chief destderata required with a view to the im- 
provement and co-ordination of the statistical work undertaken 
by different Government bureaux were: (I) an agreement as to 
the major facts necessary to be collected for each special depart- 
ment of statistics ; (2) uniformity in the processes by which these 
facts were got together; (3) co-ordination of the methods 
whereby the materials thus collected were systematised and 
made use of ; (4) the adoption, as far as possible, of the calendar 
year as the universal statistical period, so that when comparisons 
were made they should alway relate to the same dates ; (5) the 
general adoption of the metrical system of weights, measures, 
and currency. 
Herr Kéro6si spoke ‘‘On the Unification of Census Record 
Tables.” The voluminous and polyglot census results of the 
world were, he found, practically non-comparable, and he pro- 
ceeded to sketch a uniform scheme of record tables by which we 
should arrive at one bound at the highest aim of statistics—the 
possession of a uniform description of the different nations and 
of all mankind as regarded sex, age, civil state, illiteracy, occu- 
pations, &c. 
Mr. F. Y. Edgeworth, in a paper entitled ‘‘The Methods of 
Statistics,” confined himself to the treatment of numerical 
means. He showed that if we take several means of pheno- 
mena belonging to one and the same class (e.g. statures of men), 
each mean derived from numerous observations, the set of values 
thus presented would in general [fulfil a certain simple mathe- 
matical law. The general formula involved a constant or co- 
efficient peculiar to each class of phenomena, which must be 
discovered by experience. When this operation had been per- 
formed we had an apparatus for testing whether any given mean 
was or was not exceptional, indicative that the set of things of 
which the datz: was the mean might [(as compared with other 
phenomena of the same general class) be regarded as belonging 
to a distinct species. A pretty illustration of important prin- 
ciples was afforded by the statistics of a wasp’s nest, ‘‘the 
image of trade which wasps entering and issuing from their nest 
present.” It appeared that the exports and imports of this 
miniature commerce fluctuated with mathematical regularity. 
As further illustrations of the variety of interests amenable to 
| the general law, he adduced the attendance of the members of 
| a club at a fable d'héte, and the frequency of dactyls in the 
Latin hexameter. The conditions postulated by the Calculus of 
Probabilities were particularly well exemplified by the fluctua- 
tions of the Virgilian rhythm. In conclusion, he alluded to the 
simpler methods of statistics, and maintained that the mathe- 
matical, as compared with the more elementary, organon could 
produce the same effect with less trouble, or, with the same 
trouble, greater effect. 
M. Emile Levasseur, Member of the Institute and Professor 
at the College of France, initiated a discussion on the graphic 
method applied to statistics, exhibiting diagrams and cartograms 
or statistical maps illustrating his views. Prof. Marshall, of 
Cambridge, who followed, advocated the use of a standard 
gauge for historical curves in order to simplify references to the 
graphic method of statistics, and pointed out dangers in the em- 
ployment of curves arising from their deceptive appearance to 
the untrained eye. He suggested a ready means of testing the 
values of curves under comparison. 
Yesterday was entirely occupied by a conference and discus- 
sion on the subject of an International Statistical Institute, the 
establishment of which was virtually agreed to. 
UNIVERSITY AND EDUCATIONAL 
INTELLIGENCE 
CAMBRIDGE.—At the annual election at St. John’s College 
on June 22, the following awards were made to students of 
Mathematics, Natural Science, and Medicine :— 
Foundation Scholarships.— Mathematics: Love, Fletcher 
