958 



NATURE 



[December 29, 192, 



Societies and Academies. 

 London. 



( ! Mill' ■ ; ■'. '.M;ro read : 



( <.i till- IP. 1 1 hem border 



01 iMiiinDoij uciwccn wmddon I' ' ''■"-' in 



Down. The Lower Curbonifci' j'f 



.1.. :.!,., 1 j,,,^, ^ r.fnvcr Aluminous .uni <i c .m.iu.wus 

 I he l.itiri I (iiiinicnccs with grey shales above 

 i wwti .\Iuiuinuu.s scries, without any physical 

 t< iMiiv, and contains a volcanit Lmd, generally in a 

 liaguicntar)' condition, mixed wiih ash. slate, and 

 other fragments, .md iiii|)ri-,L;na1i-d witli < lurl ; l>ut, 

 at Etist T luionli >u II, tlu- rock is more solid, and is a 

 (|ii.iii topliyif. I he corresponding mixed 



iL;Ht(Mi .1 till- north-western Dartmoor border, 



which have been variously di -ii!'-d .w- altered 

 keratophyres. Above the \(iK,iinr ImuiI .m- two 

 hiiicstoiu -areas : one on the west, near Whiddon 

 Down, and, separated by quart/ose rocks, another 

 limestone-ana at Drewsteignton. Throughout the 

 length of 1' nil I considered, the top of the Cal- 

 careous Series is formed of grey shales, with hard 

 rock-bands which pass upwards into the Upper 

 Aluminous Series. The granite south of the Carbon- 

 iferous border-rocks shows three separate intrusions, 

 all from the same magma, but showing sulHcient 

 differences to separate them. — D. J. Farquharson : 

 The geology of southern Guernsey. With the possible 

 exception of some dykes of doubtful Palaeozoic age, 

 the whole of Guernsey consists of pre-Cambrian rocks 

 — gneisses and schists in the south ; unfossiUferous 

 shales and grits at Pleinmont ; and a series of in- 

 trusions in the north, which range from homblende- 

 gabbro through diorites and tonalites to granites with 

 their accompanying dykes. These dykes not only 

 pierce the last-named suite, but also the gneisses and 

 grits of the south. 



Paris, 



Academy of Sciences, November 26. — M. Albin 

 Haller in the chair. — E. L. Bouvier : Ormiscodes 

 gregatus, a moth the larvae of which group together 

 to build complex pouches. A description of the 

 building habits of a new species of Ormiscodes found 

 by M. Grisol in the neighbourhood of San Fernando 

 d Apure, Venezuela. The pouch is built in common, 

 and may contain 10 to 12 cocoons. The name 

 Ormiscodes gregatus is proposed for the species. — 

 G. Friedel : The black inclusions contained in Cape 

 diamonds. These inclusions have been regarded as 

 graphite, but without clear proof. E. Cohen has 

 shown in a large diamond of 80 carats that the 

 inclusion was a flattened crystal of oligist, and has 

 concluded that many inclusions, if not all, are oligist. 

 The author regards these conclusions as too sweeping, 

 and shows that in the case of a diamond in the 

 University Museum at Strasbourg the inclusion was 

 certainly not oligist, but was very probably graphite. 

 — M. Aimd Cotton was elected a member of the section 

 of general physics in the place of the late J. Violle. — 

 Harald Bohr : The approximation of nearly periodic 

 functions by trigonometrical summation. — Pierre Hum- 

 bert : The confluences of Clausen's series. — L6on 

 Pomey : Linear integro-differential equations with 

 several variables. — Ren6 Lagrange : Systems con- 

 nected with linear differential equations. — Paul Bon- 

 nier : Thin rectangular plates with edges resting on 

 a fixed surface. — Ernest Esclangon : Ghding flight 

 without motive power. — C. E. Guye : The motion of 

 the gas in the electromagnetic rotation of the electric 

 discharge. In the case where the action of the posi- 



tive ion« is alone concerned in imparting a movenu i; 

 of rotation to the gas, the observed velocity V' can ! 

 put in the form 



^ = i2r<T«MmL*"^M-.Nj' 



R. Mesny .md I'D 

 telegraphy. With 

 sible to utilise pai 

 bundle of radiatioi 



1)V an arran'Tnicnl 



when - ''if charge of the ion supp(»ed cc • ' 

 that -ctron, H the magnetic field pf' 



the K.ww.M., ' ••• ♦'■'• radius and mn&s ■-. 



molecule or ]>< tlic total number 01 ni':. 



cules, ioni.scd .. .\ th<' iiimdi<r ,,{ o.,vi' 



ions contained m unit volume <j1 

 expression allows tlic auoro.xima- 



ry short waves m wire)' 

 ■rt wave-lengths it is jx 

 as to direct t; • 

 1 )■■ ..m! .s.i\cs are produi • d 

 1 t wo symmetrical triodes : wav 

 oi wa\c-l(n^;th oi 10 metres can be produced, a:, i 

 telephonic communications have been produced with 

 these at a distance of two kilometres without using 

 mirrors. — Paul Woog : The resisiance to rupture, 

 lateral compression and equilibrium, of monomolecular 

 layers of various substances in thin films on water. — 

 Rene Audubret : The influence of polarisation on 

 photo-voltaic effects. The mechanism of the pheno- 

 menon. The results of the experiments described can 

 be expressed in terms of the Nemst theory' by saying 

 that tight acts on the electrodes by modifying the 

 solution tension of metals, with an intensity and 

 sense connected with the state of polarisation of the 

 plate. — J. Pouget and D. Chouchak : The radio- 

 activity of the mineral waters of Algeria. — \. Lassieur : 

 An arrangement for electrolysis with graded potentials. 

 The method of Sand and of A. Fischer is modified by 

 replacing the potentiometer measurement by a milli- 

 voltmeter and a high resistance. — Camille Matignon : 

 A new reaction for the preparation of strontium. 

 Strontia is heated in an iron tube with silicon and 

 the strontium condensed in the cool part of the 

 tube. — M. Faillebin : The hydrogenation of certain 

 ketones in the presence of pure or impure platinum 

 black. — A. Daucet : The action of xanthydrol on 

 semicarbazide, the substituted semicarbazides, the 

 semicarbazones and benzoylhydrazine. The raono- 

 xanthylsemicarbazide is showTi to possess the con- 

 stitution NH2.NH.CO.NH.CH(C,H7)jO, the hydra- 

 zine radicle remaining' tree and capable of combining 

 with aldehydes aud ketones in the usual manner. — 

 P. Gaubert : The optical properties of graphite and 

 graphitic oxide. The index of refraction of graphite 

 is between 1-93 and 2 07 ; the crystal is optically 

 negative. — David Rotman-Roman ; Contributions to 

 the lithology of the Yemen ; deep rocks and non- 

 differentiated lode - bearing rocks. — Albert Michel- 

 Levy : Some eruptive rocks from the neighbourhood 

 of Toulon (Var). — Leon Bertrand and L^once Joleaud : 

 The relations between the crystalline and sedimentary 

 formations in the western part of Madagascar, between 

 Betsiboka and Tsiribihina. — R. Dongier : Magnetic 

 measurements carried out in Dauphine, Savoie, and 

 Bresse. — r>cau!ard de Lenaizan : The earthquake of 

 November 10. 10J3. This shock was recorded on the 

 barograph at Mout]icllier at 3.40 a.m. — Lucien Daniel : 

 New researches on the migration of inulin in grafts > ■! 

 Compositeae. — .\. Guilliermond ; New obser\*ations ■ tt 

 the evolution of the chondriome in the embr\-onic - 

 of the Liliaceae. — P. Lecomte du Noiiy : Meaning ' 

 the maximum fall of surface tension of the bL '. 

 serum. — L. Mercier and Raymond Poisson : Contril' .- 

 tion to the stud\- oi the atrophy of the wings and 

 muscles of flight in the Forficulidas. — Alain Caillas : 

 The composition of propolis of bees. Propolis, or bee 

 glue, contains 70 per cent, of resins and 30 per cerit. 

 of wax. — I^ouis Boutan : The two zones of external 



NO. 2826, VOL. 112] 



