
AvuGUST 5, 1915] 
important journals into consideration. If all who are 
engaged in preparing general subject-indexes were to 
agree as to which periodicals should be indexed, and 
were to publish beforehand the names of the periodicals 
they proposed to index, it is possible that such action 
might have influence upon authors who have not yet 
decided where they should publish. Unfortunately 
the periodicals excluded from the list will immediately 
show cause why they should be included. We have 
no doubt that the Athenaeum will find a way of deal- 
ing with this difficulty, and we wish our contemporary 
success in its new undertaking. 

SOCIETIES AND ACADEMIES. 
EDINBURGH. 
Royal Society, June 28.—Dr. Peach, F.R.S., vice-pre- 
sident, in the chair.—Prof. J. W. Gregory : Contribu- 
tions to the geology of Benguella and some Cretaceous 
Echinoidea from the north of Lobito Bay.—G. W. 
Tyrrell: Notes on rocks obtained in Angola by Prof. 
Gregory.—R. B. Newton: Some Cretaceous shells 
from Angola.—G. C. Crick: Some Cephalopoda 
from Benguella.—Mrs. Margaret F, Romanes: Notes 
on an Algal Limestone from Angola. These six con- 
nected papers were based on the visit in 1912 of Prof. 
Gregory to Angola and Benguella, Portuguese West 
Africa, and on the material collected and brought home 
by him. The earliest explorers of this region were 
Livingstone, who described the chief features of the 
physiography, and Cameron, who discovered Cretace- 
ous rocks as well as widespread distributions of granite 
and gneiss. The Cretaceous rocks begin on the coast 
and end inland in great conglomerates at the floor of 
the old plateau of gneiss. The following conditions 
were recognised and described: Bihé Sandstones con- 
sisting of soft beds giving rise to the wastes known as 
the ‘‘hungry country”’; Oecendolongo sandstones, 
rhyolites, and tuffs, often like the Old Red Sand- 
stone, referred by some to the Devonian, by others to 
the Torridonian; Lepi greywackes with cherts, tuffs, 
and slates; Huambo Quartzites, pre-Torridonian. The 
coast is traversed by numerous step faults, cutting 
through the Cretaceous rocks. The fossils of these 
rocks are described by R. B. Newton. A number of 
the species are new to the area.—W. F. P. M’Lintock : 
The zeolites and associated minerals from the 
tertiary lavas around Ben More, Mull. The peculiar 
facies of vesicle-minerals in a belt of. lavas traceable 
from areas free from contact metamorphism up to the 
margin of one of the big acid intrusions is described. 
The non-metamorphosed rocks are albitised olivine 
basalts, in which the olivine is completely, and the 
augite partially, chloritised. The vesicles are filled 
with chlorite, albite, epidote, prehuite, and scolecite 
deposited in the order named. Frequently these 
minerals are seated upon a coarsely crystalline layer 
of albite, augite, magnetite, and chlorite, with which 
the vesicle is lined, and it is concluded that the cavi- 
ties were filled during the cooling of the lava. By 
contact metamorphism the contents of the amygdales 
of the lavas around the margins of the intrusion have 
been altered; the chlorite has gone to hornblende, the 
scolecite to prehnite, epidote, and ultimately to garnet; 
the prehnite, to epidote and garnet; whilst the epidote 
is replaced by garnet and aphene. The effect of the 
metamorphism has been generally to build up the 
minerals in the reverse order to that in which they 
were originally deposited in the vesicles.—R. C. 
Mossman: A see-saw of atmospheric pressure, tem- 
perature, and wind velocity between the Weddell and 
Ross Seas. By a comparison of the departures from 
the normal for each of these data during the years 
1902-4, Ig10-12 evidence was obtained of an opposite 
NO. 2388, VOL. 95] 
NATURE 

637 

phase relationship or see-saw of meteorological condi- 
tions over these seas. The discussion formed part of 
a much wider inquiry into the meteorology of ant- 
arctic regions.—W. J. Walker: The magnetic quality 
of iron and steel as affected by transverse pressure. 
The compressing force acted perpendicular to the 
direction of magnetisation. The induction was 
measured ballistically. The general result was diminu- 
tion of susceptibility with increase of transverse pres- 
sure; but there were variations from this general 
result which demanded further investigation.—W. 
Hill: Chalk boulders from Aberdeen and fragments 
from the sea-floor off the Scottish coast; and notes 
on the structure of the challx occurring in the west of 
Scotland. These important papers were found among 
the author’s possessions after his death.—Prof. E. 
Topsent: Supplementary paper on the sponges col- 
| lected by the Scotia Scottish National Antarctic Expe- 
dition.—Dr. R. Kidston: The fossil plants of the 
Forest of Wyre and Titterston Clee Hills coalfields. 
With remarks on the geology of the coalfields by T. C. 
Cantrill and E. Dixon. 
Paris. 
Academy of Sciences, July 26.—M. Ed. Perrier in the 
chair.—G. Bigourdan : The unpublished correspondence 
of the astronomer, J. N. Delisle.—J. Boussinesq : The 
importance of the rudimentary dynamics of Aristotle 
in the progress of Mediterranean civilisation.—C. 
Gutton: An induction balance designed for the detec- 
tion of buried shells in ground under cultivation. 
Owing to the danger to agriculturists due to the pre- 
sence of unexploded shells buried in the soil and the 
liability of explosion owing to contact with a plough, 
the author has devised a modification of the Hughes 
induction balance by means of which two persons can 
thoroughly explore a hectare of land in about. three 
hours.—J. Maldiney : The retarding action of sugar in 
the development of photographic negatives and the 
permeability of gelatine to the metolhydroquinone 
developer, used alone or with sugar. A plate giving 
a complete image in five seconds under the influence 
of the developer alone can be retarded by the addition 
of sugar, the addition of 60 grams of sugar per 
too ¢.c. of developer causing a retardation of from 
three to five minutes. The action appears to be due 
to physical causes, the increased viscosity of the solu- 
tion rendering the penetration of the gelatine emulsion 
sivwer. 
WasuHincton, D.C. 
National Academy of Sciences, July 15 (Proceedings 
No. 7, vol. i.).—W. S. Adams and F. G. Pease : Nova 
Geminorum No. 2 as a Wolf-Rayet star. A con- 
tinuous series of observations on Nova Geminorum 
No. 2 has shown the development of the spectrum of 
| this star through the successive stages characteristic 
| of nove into one very strongly resembling that of 
planetary nebulz ; and then, by the gradual elimination 
of the nebular lines and their replacement by Wolf- 
Rayet bands, into a spectrum identical with this char- 
acteristic type of stellar spectra.—A. A. Michelson : 
The ruling and performance of a ro-in. diffraction 
grating. A to-in. grating (actual ruled surface 9-4 in. 
by 28 in.) having a theoretical resolving power of 
about 660,000, shows an actual power of about 600,000. 
The methods of obtaining exact ruling is also dis- 
cussed.—E. E. Barnard: A singular dark marking on 
the sky. From a dark object in Cepheus and those 
in Taurus the author gets the impression that the 
interstellar spaces are suffused with a feeble nebulosity 
and that the dark marks are due to the projection 
upon this background of nearer dark, opaque objects. 
—A. L. Parson: A highly sensitive electrometer. The 
principle of working in a condition approaching in- 
stability is used to increase greatly the sensitiveness 
