282 
On the importance of geology it is needless here to 
dwell. Geology has its own place, and that a high 
one, among the sciences; without due provision for its 
study no university is complete. Geologists will be 
profoundly grateful, therefore, to Prof. and Mrs. Herd- 
man for having completed the geological chairs in the 
English universities. Liverpool has long been such an 
active centre of geological work that the lack of a 
chair in the science at the University was a regrettable 
deficiency. New conditions of life have brought with 
them a growing demand for men whose scientific train- 
ing shall include not only a knowledge of geological 
aspects of geography, but also of the earth’s mineral 
resources. The war has cost science and the universi- 
ties so much in life and brain, and also in wasted 
effort, that the example set by Prof. and Mrs. Herd- 
man in establishing such a useful and appropriate 
memorial to their son will, we hope, be followed by 
others. 
A pupstic lecture on ‘Chemistry and its Relation to 
National Affairs *’ will be delivered by Sir William A. 
Tilden, at Birkbeck College, Chancery Lane, on Tues- 
day, December 12 (Founder’s Day). at 5.45 p.m. The 
chair will be taken by Sir Alfred Pearce Gould, Vice- 
Chancellor of the University of London. The lecture 
is open to the public without fee or ticket. : 
AccorDING to the Miinchener medizinische Wochen- 
schrift the number of students during the summer 
semester of 1916 in the Austrian universities. was as 
follows :—Vienna, 3472; Prague (Czéch university), 
1891; Cracow, 1281; Lemberg, 1174; Graz, 647; 
Prague (German university), 638; Innsbruck, 584. 
The proportion of medical students was highest at 
Vienna and at Graz (both about 30 per cent. of the 
total). At Vienna nearly two-fifths of the medical 
students were women. . 
Tue evening classes held at University of London, 
King’s College, Strand, W.C., will be open during 
the session 1916-17 to members of his Majesty's 
Forces of all ranks wearing uniform who have at any 
time passed the matriculation examination of the Uni- 
versity of London, or any examination exempting 
therefrom, and are desirous of spending what time is 
available after their military duties in furthering their 
education in arts or science. In view of the- fact 
that the attendance of such students will be liable to 
interruption, no tuition fee will be charged during the 
war for any classes or course of study entered upon. 
Those who attend these classes may be registered as 
internal students of the University of London. 
‘THe General Medical Council on December 2 adopted 
by a majority a proposal to make Latin optional in 
the medical higher preliminary examination, The 
Education Committee of the council, in a report, ex- 
pressed the opinion that the possession by a student of 
a senior leaving examination certificate or its equiva- 
lent, the matriculation certificate of the universities, 
affords ample evidence that all the objects of the coun- 
cil in preseribing a preliminary examination in general 
knowledge are fully realised. The report recom- 
mended the council to accept such certificates without 
further proviso than that they should embrace at least 
four subjects, including English and mathematics, the 
two or more additional to be chosen from among the 
principal subjects of the school curriculum. On the 
following day the question of making Latin optional 
in, the preliminary examination of candidates for ad- 
mission to the medical curriculum belonging to the 
junior class-was discussed by the council, and even- 
tually, at the suggestion of the president, Sir Donald 
Maealister, the question was referred back to com- 
mittee. 
NO. 2458, VOL. 98] 
NATURE 
[DECEMBER 7, 1916 
SOCIETIES AND. ACADEMIES. 
LONDON. ; 
Royal Society, November 23.—Sir J. J. Thomson, 
president, in the chair.—Sir Robert Hadfield and Dr. 
E. Newbery: The corrosion and electrical properties of 
steels. The condition that a metal shall dissolve in an 
acid with evolution of hydrogen is :—Single potential — 
of metal + over-voltage < single potential of hydrogen 
electrode, all measurements being, of course, made in — 
the given acid. If therefore we assume that the atmo-— 
spheric corrosion of a metal is a process similar to that 
of dissolution in an acid, it should be possible to pre- 
dict the corrosion-resisting power of a given metal by 
determining its single potential referred to. a hydrogen 
electrode, together with its over-voltage in a. suitable 
electrolyte. Experiments on a number of special steels 
have been carried out to test the validity of the above 
assumption. The over-voltage, single potential, and 
loss of weight in acid of each soecimen were determined 
and compared with the atmospheric corrosion observed 
after exposing clean surfaces to the air for ten weeks? 
The results showed that the electrical method gives 
decidedly better estimates of the conrosion- a 
powers of steels than the acid method, and althoug 
neither method gives trustworthy estimates in all cases} 
vet the electrical method appears to rest-upon a sound 
theoretical foundation, and is probably capable of fur- 
ther developments which may result in the formation 
of trustworthy corrosion data.—Dr, A. E. H. Tuttoh: 
Monoclinic double selenates of the nickel group. In 
this paper the results are given of the investigation’ of 
the double salts, potassium nickel selenate, rubidium 
nickel selenate, caesium nickel, selenate, and ammo- 
nium nickel selenate, each containing six molecules of 
water of crystallisation. The results are in line’ with 
all those already published for the complete monoclinic 
double sulphate series with 6H,O, and for the iso- 
morphous magnesium and zinc double selenate groups. 
The morphological and physical properties exhibit the 
progression in. accordance’ with the atomic weight of 
the alkali metal brought out by the previous work, 
and the ammonium salt is shown to belong to the 
isomorphous series, and to exhibit the peculiar traits 
described in connection with the other ammonium salts 
of this monoclinic series already dealt with.—Dr. - 
A. E. H. Tutton: X-ray analysis and topic axes of 
the alkali sulphates and their bearing on the law of 
valency volumes. An X-ray spectrometric . analysis, 
carried out with the author’s crystals in, the laboratory 
of Prof: W. H. Bragg by Prof. A. Ogg and Mr. F. 
Lloyd Hopwood, of the rhombic crystals of the allali 
sulphates R,SO,, where R is K, Rb, Cs, and NH,, 
has indicated that four molecules of R,SO, are con- 
tained in the unit rectangular cell of the space-lattice, 
as suggested by the author in 1894. The atoms of 
sulphur occupy the corners of the rectangular’ cell and 
the middle point of each side. The planes of sulphur 
atoms parallel to the (001) face are of pseudo-hexa- 
gonal structure, the atomic centres being arranged in 
nearly regular hexagons, as suggested by Federov and 
adopted by the author. The metallic atoms are also 
probably arranged in nearly regular hexagons. It is 
fully substantiated that the constants, molecular 
volume. and topic axial ratios afford true indications 
of relative volume and dimensions of elementary space- 
lattice cells in the cases of crystal structures of iso- 
morphous series.—Dr. T. J. I’a. Bromwich ; The scat- 
tering of plane electric waves by soheres. The first 
section contains a very general solution of the electro- 
magnetic equations in curvilinear co-ordinates, and it 
is proved that this solution contains as particular cases 
those previously obtained by Hertz, Fitzgerald, Ray- 
leigh, Love, and Lamb. ‘This general solution is then 
applied to the problem indicated in the title of the 
