364 
NATURE 
[ NOVEMBER 20, 1913 
Arica,’ where fossils occur which indicate an Upper ' generally recognised, has to some extent been obscured 
Jurassic (Callovian) age. They are interbedded with 
thick sheets of basic enstatite-andesite. The erosion 
of the river-valleys that has brought to light the 
Jurassic sediments has also laid bare the underlying 
plutonic mass of granodiorite, which may be regarded 
as the deep-seated core of the western ‘‘ Cordillera.” 
The western Cordillera is essentially a volcanic range. 
The enormous amount of volcanic material emitted 
has almost completely concealed the underlying rocks. 
The lavas can be resolved into three main groups, 
characterised by their dominant ferromagnesian 
mineral, succeeding one another in age according to 
a law of increasing basicity. The ‘ Altaplanicie,” is 
almost entirely covered by horizontal sheets of volcanic 
ash, tuff, and pumiceous lava, described as the Mauri 
Volcanic Series. The occurrence in an interbedded 
layer of gravel, of a fragment of a jaw of ‘* Nesodon,” 
almost identical with specimens from the Miocene 
beds of Santa Cruz, affords a clue for an estimation 
of their age. They are overlain on the east by 
gravel-deposits of the Desaguadero River, the highest 
terrace of which was found to contain remains of 
Mastodon, Megatherium, Scelidotherium, and other 
Pleistocene vertebrates. From beneath these super- 
ficial deposits crops out a series of unfossiliferous red 
sandstones and conglomerates. These are divided 
into two groups—a younger series of Cretaceous 
age resting with pseudoconformity on an older Permo- 
Carboniferous group. The Carboniferous formation 
is nowhere exposed along the line of section. The 
eastern Cordillera is composed chiefly of steeply- 
dipping Devonian slates and quartzites. 
Linnean Society, November 6.—Prof. E. B. Poulton, 
F.R.S., president, in the chair.—H. Hamshaw 
Thomas and Miss Nellie Bancroft: The cuticles of 
some recent and fossil Cycadean fronds. The inves- 
tigation was undertaken with the view of determining 
the probable relationships of the modern group to the 
Mesozoic Cycadophyta.—Prof. W. A. Herdman: 
Spolia Runiana II. Results of the past season’s 
dredging. The author described the course taken by 
the yacht off the west coast of Scotland, and showed 
a long series of slides displaying the scenery and 
bird-life of the unfrequented regions visited. 
Mineralogical Society, November 11.—Anniversary 
meeting.—Dr. A. E. H. Tutton, F.R.S., president, in 
the chair.—A. Hutchinson and A. M. MacGregor: A 
crystalline basic copper phosphate from ‘Rhodesia. 
The mineral occurs at the Bwana M’Kubwa copper 
mines as a crust of minute, brilliant, peacock-blue, 
orthorhombie crystals, associated with malachite. 
Axial ratios a:b:c=0-394:1:1-01; forms 110, 011; 
hardness 4-5; specific gravity 41. Chemical com- 
position, determined by an analysis of a small quantity 
of carefully selected material, approximates to the 
formula 2Cu,(PO,),..7Cu(OH),; no water is lost on 
heating to 190°. Although it has much the same 
composition as some minerals included in the pseudo- 
malachite family, it differs widely in its physical char- 
acters from dihydrite, the only well-defined crystalline 
member of the group, and is probably a new species.— 
Dr. G. T. Prior: The meteoric stone of Wittekrantz, 
South Africa. The stone, which fell on December 9, 
1880, at the farm, Wittekrantz, Beaufort West, Cape 
Colony, is slightly chondritic, and consists of the 
usual aggregate of olivine and bronzite, with particles 
of nickeliferous iron and troilite. In chemical and 
mineral composition it is very similar to the Baroti 
meteorite previously described.—Dr. G. T. Prior: The 
remarkable similarity in chemical and mineral composi- 
tion of chondritic meteoric stones. The close similarity 
presented by most chondritic meteoric stones, although 
NO. 2299, VOL. 92] 
by the unduly elaborate classifigations which have been 
devised. A review of the quantitative mineral com- 
position of forty-two chondritic stones and a critical 
examination of the published analyses of others lead 
to the conclusion that almost all those at present 
known are, except for some variation in the amount 
of nickeliferous iron, practically identical in chemical 
and mineral composition, the identity extending even’ 
to the chemical composition of the individual con- 
stituents. They approximate to the type with the’ 
following percentage mineral composition :—Nickel- 
iron (Fe: Ni=10), 9; troilite, 6; olivine (Mg : Fe=3), 
44; bronzite (Mg: Fe=4), 30; felspar, 10; chromite, 
&c., 1.—Arthur Russell: Notes on the minerals oceur- 
ring in the neighbourhood of Meldon, near Okehamp- 
ton, Devonshire. The principal species are datolite, 
in crystals sometimes 23 cm. in length, sea-green in 
colour, and nearly transparent, polysynthetically de- 
veloped, and showing a cleavage parallel to oor; 
apophyllite, in three types—square, tabular, and pyra- 
midal; pyrrhotite, in thin hexagonal plates; tour- 
maline, in black, brown, green, blue, and pink 
crystals, sometimes zoned; garnet, in colourless cubo-. 
dodecahedra, and trapezohedra, sometimes including 
wollastonite hairs; wollastonite, abundantly in pure 
white, fibrous masses.—J. B. Scrivenor: A calcium- 
iron-garnet from China. It is interesting on account 
of its unusually easy solubility in hydrochloric acid 
without ignition. 
Mathematical Society, November 13.—G, T. Bennett : 
The skew-isogram mechanism.—G. H. Hardy and 
J. E. Littlewood: Tauberian theorems concerning 
power series the coefficients of which are positive.— 
G H. Hardy: Lambert’s theorem.—J. E. Campbell : 
(1) The connection between surfaces the lines of curva- 
ture of which are spherical and surfaces the inflec- 
tional tangents of which belong to linear complexes. 
(2) Surfaces the systems of inflectional tangents of 
which belong to systems of linear complexes.—W. H. 
Young: Integration with respect to a function of 
bounded variation.—W. W. Johnson: The computation 
of Cotes’s numbers, and their values up to n=20.— 
S. G. Soal: Some ruler constructions for the co- 
variants of a binary quantic.—T. C. Lewis: Analogues 
of orthocentric tetrahedra in higher space. 
Paris. 
Academy of Sciences, November 10.—M. F. Guyon 
in the chair.—Emile Picard: Remarks concerning an 
integral equation considered by M. Charlier.—H. 
Deslandres and L. d’Azambuja: The action of a mag- 
netic field on the ultra-violet band spectrum of water 
vapour. A new property of the regular series of lines 
forming the band. The third group of the nitrogen: 
bands shows the Zeeman effect; under similar con- 
ditions the water vapour band is not doubled by the 
magnetic field, but all the lines constituting the band 
are displaced.cArmand Gautier: Fluorine as a con- 
stant element in the emanations from the earth’s 
crust. Fluorine (probably as hydrofluoric acid) has 
been detected and estimated in the gases from a 
fumerolle at Vesuvius, in the proportion of about 
one part in 10,000. Fluorine has also been found in 
the fumerolles of Tuscany.—E. Jungfleisch and Ph. 
Landrieu; Researches on the acid salts of dibasic 
acids. The dextrorotatory camphorates: the 
potassium camphorates.—C. V. L. Charlier: Terres- 
trial refraction and the constitution of the atmosphere. 
—M. Fessenkoff: The equatorial acceleration of the - 
sun.—MM. Chipart and Liénard: The sign of the real 
part of the roots of an algebraic equation.—Georges 
Pélya: An algorithm always convergent to obtain 
polynomials with the best approximation of Tcheby- 
