502 



NA TURE 



[March 26, 1908 



(4) The motor areas are characterised histologically by 

 the presence of Betz cells. Localisation by histological 

 study is therefore possible, and there is a close corre- 

 spondence of the results so obtained with those obtained 

 experimentally. 



(5) There are, however, two types of motor cortex in the 

 lemur's brain. The large type of Betz cell is found in the 

 greater part of the motor cortex, particularly where limb 

 and body movements are represented. The smaller type 

 of Betz cell is found in the area governing face, tongue, 

 ear, and eye movements, and in this excitable region there 

 is a layer of granules ; it is therefore probably sensori- 

 motor. 



(6) Although the investigation relates in the main to 

 motor representation, histological examination of the 

 occipital (and especially calcarine) region shows it to 

 possess the structural characters of the visual cortex in 

 other animals. That no eye movements could be elicited 

 by faradic stimulation of this region is probably due to 

 the difficulty of the experiment, as explained in the text. 



February 13. — " On the Determination of Viscosity at 

 High Temperatures." By Dr. C. E. Fawsitt. Com- 

 municated by Prof. Andrew Gray, F.R.S. 



Measurements of viscosity at temperatures higher than 

 300° C. to 400° C. present considerable difficulties, and 

 until the present year this subject has not been touched 

 by experimenters. 



The present communication contains a description of 

 the method used. The method is suitable for the measure- 

 ment of the viscosity of liquids which are not very viscous 

 —not more than, say, fifty times as viscous as water — and 

 is especially designed for the determination of the viscosity 

 of molten metals and salts. The determination of the 

 viscosity of salts up to 1200° C, or even higher, can be 

 quite satisfactorily carried out by this method. Deter- 

 minations of the viscosity of metals are much more 

 difficult, owing to the impossibility of preventing a certain 

 arnount of surface oxidation. The smallest trace of surface 

 oxidation will completely spoil a series of observations, 

 and the prevention of oxidation is really the chief difficulty 

 in such determinations. 



The method used is based on the method originally given 

 by Coulomb, the modifications introduced being due to 

 the special nature of the determinations. In Coulomb's 

 rnethod a horizontal disc is allowed to execute horizontal 

 vibrations about a vertical suspending wire attached to 

 its cen'tre. The viscosity of the liquid can be calculated 

 from the rate of decay of amplitude. 



In making a series of observations with this apparatus, 

 the disc is allowed to sink about half an inch below the 

 surface of the liquid. The amplitude of the oscillations 

 is indicated by a pointer (wire) at right angles to the top 

 of the iron rod which carries the disc, and the pointer 

 moves above a circular scale divided into degrees. 



With this apparatus, the determination of the viscositv 

 of a liquid is accurate to within 5 per cent, of the absolute 

 value, unless there are special circumstances, as in the 

 case of molten metals, when the results are apt to come 

 out considerably too high. 



The results obtained show the availability of this method 

 for the determination of viscosity up 'to the highest 

 temperature at which a platinum capillary has been used. 



Chemical Society, IVIarch 5.— Sir William Ramsay. K.C.B., 

 F.R..S., president, in the chair.— The solubilitv of iodine in 

 water : H. Hartley and N. P. Campbell, the solubilitv 

 of iodine in water has been determined at 18°, 25°, 35°. 

 45°, and 55°, and the heat of solution has been' calculated 

 from the temperature coefficient of the solubility. — Nitro- 

 derivatives of o-xylene (preliminary note) : A. W. 'Crossley 

 and Miss N. Renouf. o-Xylene' vields two trinitro-deri- 

 vatives, the one melting at 71° and'the other at 115° (com- 

 pare Noelting and Thesmar, Ber., igo2, xxxv., 634). A 

 new dinitro-o-xylene melting at 82° has also been isolated, 

 and a_ substance melting at 115° which is a dinitro- 

 derivative of some condensed benzene ring derivative. — 

 Substituted dihydrobenzenes, part ii., i : i-dimethyl-A=:'- 

 dihydrobenzene and i : i-dimethyl-A=:^-dihydrobenzene : 

 A. W. Crossley and Miss N. Renouf. Dim'ethvldihvdro- 

 benzcne prepared by the elimination of 2HBr from 

 3 : S-tiibromo-i ; i-dimethylhexahydrobenzene has been 

 proved to consist of a mixture in approximately equal 

 NO. 200J. VOL. 77I 



parts of these two hydrocarbons, thus refuting the adversr 

 criticisms of Harries and Antoni (.-liMia/cH, 1903, cccxxviii., 

 66) on the work published by Crossley and Le Sueur (Trans.! 

 1902, Ixxxi., 821). — The viscosity of aqueous pyridine solu- 

 tions : A. E. Dunstan and F. B. T. Thole. The authors 

 have repeated their experiments on the viscosity of aqueous 

 pyridine solutions, and find that the same discontinuities 

 occur in the curve as were previously observed (compare 

 Hartley and others, Proc, 1908, xxiv., 22). — The action of 

 thionyl chloride on the methylene ethers of catechol deri- 

 vatives, ii., piperonyloin, piperil, and hydropiperin : G. 

 Bargrer and A. J. Ewins. — Traces of a new tin-group 

 element in thorianite : Miss C. de Brereton Evans. The 

 dark brown sulphide of the new element separates with 

 arsenious sulphide, from which it differs in being soluble 

 in water, to form a deep brown solution. It yields a 

 hygroscopic brown oxide, which on reduction in hydrogen 

 furnishes a grey metal. Incidentally, proof was obtained 

 of the presence in thorianite of arsenic, mercury, bismuth, 

 molybdenum, and selenium. — The sulphination of phenolic 

 ethers and the influence of substituents ; S. Smiles and 

 R. Le Rossignol. The authors have confirmed the con- 

 clusion that the sulphonium base derived from phenetole is 

 produced in three stages, at which the sulphinic acid, 

 sulphoxide, and base are consecutively formed, by isolating 

 the sulphinic acid. — The relation between unsaturation and 

 optical activity, part ii., alkaloid salts of corresponding 

 saturated or unsaturated acids : T. P. Hilditch. — The 

 wandering of bromine in the transformation of nitro- 

 aminobromobenzenes : K. J. P. Orton and Miss C. 

 Pearson, — K new isomeride of vanillin occurring in the 

 root of a species of Chlorocodon, preliminary note : E. 

 Goulding and R. G. !?elly. The results obtained show- 

 that the odorous constituent of Chlorocodon root is a 

 monomethyl ether of a dihydroxybenzaldehyde" having an 

 odour intermediate between that of vanillin and piperonal, 

 but which is not identical with vanillin or any of its 

 known isomerides. — The volatile oil of the leaves of 

 Ocinium viride, preliminary note : E. Goulding and R. G. 

 Pelly. The composition of the oil is appro.ximatelv as 

 follows : — thymol, 32 per cent. ; alcohols (calculated as 

 C,„H,,0), 40 per cent. ; esters (calculated as C,„H|;.OAc), 

 2 per cent. ; the remainder consists chiefly of a terpene (or 

 possibly a mixture of terpenes), which is a liquid of pleasant 

 lemon-like odour, boiling at i6o°-i66°. — Experiments on 

 the synthesis of the terpenes, part xii., synthesis of terpins, 

 terpineols, and terpenes derived from the methyliiopropvl- 

 cvf/opentancs, Me.C-H,.CHMe, : W. N. Haworth and 

 W. H. Perkin, jun. — The initial change of the radium 

 emanation : N. \'. Sidgfwick and H. T. Tizard. 



Geological Society, March 4.— Prof. W. I. Sollas. F.R.S., 

 president, in the chair. — Metriorhynchtts hrachyrhynchus, 

 Deslong., from the Oxford Clay near Peterborough : E. T. 

 Leeds. Two skulls have recently been obtained from the 

 Saurian zone of the Lower Oxford Clay, in the neighbour- 

 hood of Dogsthorpe, Peterborough. The mandibles w^cre 

 missing. The two specimens have been referred to Mctrio- 

 rhynchus bracbyrhynchus. This is believed to be the first 

 recorded occurrence of the species in England. — The high- 

 i level platforms of Bodmin Moor, and their relation to the 

 deposits of stream-tin and wolfram : G. Barrow. In this 

 area there are three platforms : — one, which is marine and ' 

 of Pliocene age, terminating in a steep slope at 430 feet ; 

 j a second, at a height of 750 feet, seen about Camelford 

 i and at the foot of Delabole Hill ; and a third, a little 

 under 1000 feet, first recognised on Davidstow Moor. 

 The superficial deposits whicfi bear tin above the 750-fe('i 

 platform differ markedly at times from those below it. 

 These deposits are not so concentrated as the stream- 

 sorted material below, but they have been frequently 

 worked in past times. The veins from which the wolfram 

 is derived have been found close to the points v/nere the 

 " wash " is enriched by their denudation. The success of 

 working depends to some extent on the slope of the 

 granite-floor on which the detritus rests. On Bodmin 

 Moor the larger marshes have a floor of kaolinised granilr, 

 but there is a difficulty in working it at many points in 

 consequence of the water-logging by peaty water. 



Royal Anthropnlogical Institute, March 10 — Prof. A\ . 

 Ridgeway, president, in the chair. — The origin of tlv 

 crescent as a Mohammedan badge : Prof. Ridgeway. I ' 



