590 
NATURE 
[NOVEMBER 27, 1913 
The inquiries of the committee began in 1905, and 
have resulted in the formulation of a number of recom- 
mendations, which, however, are published as ‘‘ under 
revision.’’ With most of the recommendations all 
who have to use books will cordially agree. Thus 
the committee advise that the title-page should be 
dated in the case of all copyright books with the 
dates of previous impressions on the back or on the 
half-title. Each book should contain a list of con- 
tents and an index, and the headlines should be 
descriptive of the contents of the page. One of the 
most important and difficult parts of the inquiry 
related to the quality of the paper used in books, and 
a classification into four types was adopted : (1) papers 
of light, spongy character, or featherweight; (2) 
printing papers with a moderate finish or surface, con- 
taining not more than 15 per cent. mineral matter; 
(3) highly surfaced printing papers; (4) so-called ‘‘ art” 
papers surfaced on both sides with mineral matter. 
Class (2) is recommended for books intended to resist 
a normal amount of wear, papers in classes (1) and 
(4) being quite bad from the point of view of 
durability. Class (3) is a compromise between (2) and 
(4), and the committee evidently prefers to use class (2) 
for reading matter and for illustrations also where 
the use of half-tone blocks can be avoided. When the 
illustrations are of a kind which demands a surfaced 
paper, ‘‘it seems reasonable to suggest that the 
letterpress should be printed on ordinary paper and 
the illustrations on a thin art paper coated on one 
side only, the illustrations being guarded into the 
book.’’ There are recommendations with reference 
to printing, book-illustration, and binding, and the 
report is the result of careful work by experts in the 
subjects dealt with. The establishment of the London 
County Council classes in book production was an 
indirect result of their earlier labours, and we shall 
look forward to a further report, when we hope that 
the question of legibility will receive more considera- 
tion, especially the influence upon eyesight of the 
surface, thickness, and texture of the paper used for 
printing. 
SOCIETIES AND ACADEMIES. 
Lonpon. 
Royal Society, November 20.—Sir Archibald 
Geikie, IKX.C.B., president, in the chair.—Dr. D. H. 
Scott: Medullosa pusilla. Medullosa is a genus of 
fossil plants, with structure preserved, from the 
Carboniferous and Permian. Only one British species 
has -so far been known, Medullosa anglica, from the 
Lower Coal.Measures, the oldest and simplest mem- 
ber of the genus, with three uniform vascular 
cylinders. Medullosa pusilla from Colne, Lanes., is a 
closely allied form of remarkably small size and some- 
what simplified structure——Prof. A, F. S. Kent: 
Neuro-muscular structures in the heart. The paper 
deals .with the relations .of the structures at the 
auriculo-ventricular junction. Nerve fibres and nerve 
cells, the exact functions of which are open to con- 
jecture, are numerous in the neighbourhood of the 
junction. The present work shows that these nervous 
elements are associated with structures which lie in 
the connective tissue between the auricular muscle 
and the ventricular muscle.—George Graham and 
EP. Poulton: The alleged excretion of creatine in 
carbohydrate starvation.—J. A, Gardner and P. E. 
Lander: The origin and destiny of cholesterol in the 
animal organism. Part xi., The cholesterol content of 
growing chickens under different diets —W. E. 
Bullock and- W. Cramer: Contributions to the bio- 
chemistry of growth—the lipoids of transplantable 
tumours of the mouse and the rat. 
* “NO. 2300, VOE.@2i 
| 
Physical Society, November 14.—Prof. C. H. Lees, 
F.R.S., vice-president, in the chair.—H. R. Nettleton ; 
The thermal conductivity of megcury by the impressed 
velocity method. The paper gave an account of the 
determination of the thermal conductivity of mercury 
at the ordinary temperature of the room by the im- 
pressed velocity method first described by the author 
in the Proceedings of this society, vol. xxii., 1910. 
A mean value of 0-0201 c.g.s. units at 15-5° C. is- 
obtained for the thermal conductivity—Dr. A. W. 
Ashton; Polarisation and energy losses in dielectrics. 
The object of the paper is to discuss the relations 
which should exist between the coefficients in Pellat’s 
equation (as modified by Schweidler), giving the dis- 
placement in a viscous dielectric as a function of the 
time of charge and the P.D.—F. J. Harlow: A lecture 
experiment to illustrate ionisation by collision and to 
show thermo-luminescence. A method of demonstrat- 
ing to an audience both ionisation by collision and 
the reduction of the sparking potential by the presence 
of initial ionisation is described in the paper. 
Paris. 
Academy of Sciences, November 17.—M. F. Guyon 
in the chair.—Charles Moureu and Emile André: The 
thermochemistry of acetylene compounds. ‘The heats 
of combustion and formation of thirty-three acetylene 
derivatives have been determined, and compared with 
the analogous ethylene and saturated compounds. The 
addition of a molecule of hydrogen to acetylene deriva- 
tives evolves about 80 calories in the fatty series, rather 
less in the aromatic series.—A. Laveran; Macacus and 
dogs are affected similarly by Indian and Mediter- 
ranean kala-azar. An experimental proof of the 
identity of these two diseases.—Georges Charpy and 
André Cornu: The influence of silicon on the solu- 
bility of carbon in iron. As the silicon increases, 
the solubility of carbon in iron decreases, becom- 
ing practically nil at goo°, for 4 per cent. silicon, 
and at r1000° C., with 7 per cent. of silicon.—M. 
Gosselet was elected a non-resident member.—M. 
Giacobini: The return of the Giacobini comet 
(1900 III.). The comet 1913e is shown to be identical 
with the Giacobini comet (1900 III.).—E. Keraval: A 
family of triply orthogonal systems.—M. Tzitzéica : 
Conjugated networks.—Zodrd de Georce: The quad- 
rature of varieties—Kampé du Fériet; The ultra- 
spherical polynomials Vee y» Léon Brillouin - 
The propagation of a luminous signal in a dispersive 
medium.—Pierre Weiss and Auguste Piccard: The 
magnetisation of nitric oxide and magneton.—E. 
Ariés : Remarks on the coefficients of thermo-elasticity- 
—M. Billon-Daguerre, ,, Medard, and H. Fontaine: A 
new arrangement of the mercury lamp. A description 
of a quartz mercury-vapour lamp, giving about 3000 
candles for an expenditure of 1250 watts. The lamp 
causes practically no heating effects, and the light can 
be condensed on a celluloid film without danger. The 
point of light is absolutely fixed, and requires no 
adjustment in use.—G, Moreau; Electric couples in 
flames. An account of some electrical effects noticed 
when two platinum plates, one bearing a trace of a 
salt and the other clean, are heated together in a 
flame.—M. de Broglie: A new method giving photo- 
graphs of line spectra with R6ntgen rays.—F. O. 
Germann; Revision of the density of oxygen. The 
density of the air of Geneva. The oxygen in these 
experiments was prepared by heating potassium per- 
manganate, passed over solid potash, phosphoric 
anhydride, and mercury, and further purified by frac- 
tional distillation. Using four different density 
globes, eleven observations gave a mean density of 
1-42904 (extremes 1-42815 and 1-42941). A second set, 
in which the oxygen was not distilled, gave a mean 
value 1-42923; a third set, similar treatment to first 
