256 
NAT ORE. 
[JANUARY 14, 1904 
Tue Board of Education, in cooperation with the council | 
of the Society of Arts, intends during the present year to 
hold, in the Victoria and Albert Museum, South Kensing- 
ton, an exhibition of engravings produced by mechanical 
means, such as photogravure and other photographic pro- 
cesses, as a sequel to the exhibition of engraving and etch- 
ing held during last summer; and as great advancements 
have been made in printing in colours since the Exhibition 
of Modern Illustration in 1901, specimens of colour printing 
will be included. A committee, of which Sir William de W. 
Abney, K.C.B., F.R.S., will act as chairman, has been 
formed to advise the Board in carrying out the exhibition. 
All communications should be addressed to the secretary, 
Exhibition of Mechanical Engraving, Board of Education, 
South Kensington. 
At the monthly meeting of the Church Society for the 
Promotion of Kindness to Animals, held on Friday, January 
8, at the Church House, Westminster, it was resolved to 
present a memorial to the Government asking for a depart- 
mental inquiry into the conditions under which slaughter- 
ing is carried on, and the general treatment of animals. 
A paper was read on “* Nature-Study Conducive to Kindness 
to Animals ’’ by the Rev. Claude Hinscliff. 
Mr. J. A. GitruTH, pathologist to the Public Health 
Department, Wellington, N.Z., is reported to have made a 
new discovery with regard to anthrax (Times, January 11). 
The series of experiments which he has conducted proves 
that an animal particularly susceptible to anthrax, such as 
a guinea-pig or a rabbit, will resist enormous doses of 
virulent anthrax provided the anthrax germs be mixed with 
a greater quantity of another species of microbe that in 
itself must be non-pathogenic and incapable of producing 
any disease. These observations may ultimately prove to 
be of practical importance, and their confirmation will be 
awaited with interest. 
Pror. A. Kiossovsky, of the University of Odessa, and 
director of the meteorological system of south-west Russia, 
has published in vol. xxv. of the Journal of the New Russian 
Society of Naturalists a very interesting résumé of the 
general condition of weather prediction at the present time. 
He deals with the old method of mean values and the 
modern method of synoptic meteorology, the application of 
mathematical analysis, with periodicities (varying from two 
to thirty-five, and even one hundred and thirty-five years), 
the moon’s influence, &c. The chief object of the paper is 
to examine the method of M. Demtschinsky and the pre- 
dictions published for some years in the journal Climate. 
The predictions in question have been submitted to an ex- 
haustive examination, and Prof. Klossovsky’s conclusions 
are entirely unfavourable to M. Demtschinsky’s method and 
results. For the benefit of meteorological students the 
author suggests that, if M. Demtschinsky persists in his 
views, the matter should be referred to the independent 
decision of the International Meteorological Committee, and 
that the necessary funds should be placed at its disposal 
for the preliminary work of calculation and preparation of 
diagrams. 
Every photographer who washes his negatives carefully 
is aware of the great expenditure of water and time re- 
quired before he is satisfied that the last trace of hypo- 
sulphite of soda has been dissolved. 
times given as the length of time necessary, but 
one hour is considered sufficient. Mr. J. 
Norton, in the British Journal of Photography (January 1), 
suggests an alternative scheme for getting rid of the hypo 
No. 1785, VOL. 69] 
Four hours is some- 
usually 
in five minutes, and as he says he has given some attention 
to this question, his process may be summarised here. The 
basis on which the suggestion is made is that barium 
chloride has an exceedingly strong affinity for sulphur. On 
the addition of barium chloride to hyposulphite of soda 
both are immediately broken up; the barium unites with 
the sulphur and the soda with the chlorine, so that the 
products are barium sulphate and common salt. The 
barium sulphate being loose, very heavy, white (poisonous) 
powder, quite insoluble, can be easily rinsed off the photo- 
graphs, and the common salt remains in the solution. 
After the photograph has been taken from the hyposulphite 
of soda solution, it should be rinsed in running water for 
a minute and rubbed on both sides with a cotton swab. It 
should then be dipped for two minutes in a 5 per cent. solu- — 
| tion of barium chloride, and afterwards rinsed and swabbed 
in running water. Mr. Norton finds that five minutes is 
sufficient for this latter manipulation. He also remarks 
that the whites of the photographs are improved by this 
process. 
Two small booklets on ‘‘ Color Correct Photography ” 
and ‘‘ How a Lens Works,”’ belonging to the *‘ Photogram 
Series of Penny Pamphlets on Photography,’’ have been 
received from the publishers, Messrs. Dawbarn and Ward, 
Ltd. The first contains some facts about isochromatic and 
orthochromatic methods which will aid the photographer 
to improve his work both from the technical and pictorial 
points of view. The second tells one what the lens can and 
cannot do, and gives in simple language various pieces 
of information useful to a beginner. ‘This useful series. of 
pamphlets will no doubt find many readers. 
An account of the development. of mathematics during the 
nineteenth century is contributed by Dr. J. T. Merz to the 
Proceedings of the Durham University Philosophical 
Society. 
IN a paper contributed to the Physikalische Zettschrift, 
iv., 30, by Messrs. R. Luther and W. A. Uschkoff on the 
chemical action of R6éntgen rays on bromide-gelatin photo- 
graphic plates, the authors arrive at the conclusions (1) 
that the action of these rays is specifically different from 
that of ordinary light; (2) that short exposure to Roéntgen 
rays alters the sensitiveness of the plates to ordinary light, 
sometimes increasing and sometimes decreasing it; (3) that 
previous illumination with ordinary light does not affect the 
behaviour of bromide plates towards Rontgen rays. 
SEVERAL papers have recently appeared dealing with the 
study of ultra-microscopical particles. In the Revue 
générale des Sciences MM. A. Cotton and H. Mouton give 
a general account of the recent researches of Siedentopf 
and Zsigmondy, and Mr. E. Raehlmann, of Weimar, con- 
tributes to the Physikalische Zeitschrift the results of his 
researches on the ultra-microscopic particles contained in 
solutions of colouring matters, these researches having been — 
carried out with the aid of the instrument belonging to 
the Zeiss Laboratory in Jena. 
Tue recent attempts of engineers and others to grapple 
with thermodynamical problems falling more strictly within 
the domain of the physicist have led to the publication of a 
paper by Prof. W. S. Franklin in Science for November 
20, 1903, on the misuse of physics by biologists and 
engineers. In discussing irreversible processes, the author 
introduces the new nomenclature of *‘ steady sweeps,”’ 
““ trailing sweeps,’’ and ‘‘ simple sweeps,’’ and he maintains 
the view (rightly or wrongly) that the conception of 
temperature has no meaning except in cases of thermal 
equilibrium. 
