ifi6 



NA TURE 



[December iS, 1902 



limits. The former we would term "long spinal," the latter 

 "short spinal " fibres. In each of these main categories, there 

 can be distinguished fibres of various intermediate length. 



Again, the fibres of each cf the above two categories may be 

 classified into two sets or tracts, according to their topography 

 relatively to the cross-section of the cord. Fibres of both of the 

 above categories are situate both in the lateral columns and in 

 the ventral columns of the cord. It is useful, at least for 

 descriptive purposes, to indicate this by terminology. We thus 

 recognise in the aborally-running intrinsic spina! fibre systems 

 the following sets or tracts : — (ci) Ventral shvt fibres, (B) Ventral 

 lon% fibres, (7) lateral sli"rt fibres, (5) lateral Ion* fibres. It 

 must be added that the distinction into lateral and ventral is 

 somewhat artificial, as there exists often, especially in the case 

 of the "short" fibres, no distinct gap between the ventral and 

 lateral fields of distribution of the fibres in the transverse area 

 of the cord. 



The paper concludes with an analysis of evidence as to 

 decussation of the long and short fibres. 



December II. — "Quaternions and Projective Geometry." By 

 Prof. Charles J. Joly, F.T.C.D., Royal Astronomer of Ireland. 

 Communicated by Sir Robert S. Bill, F.R.S. 



The object of this paper is to include projective geometry 

 within the scope of quaternions. 



Chemical Society, December 4. — Dr. W. It. Perkin, 

 F. R.S. , vice-president, in the chair. — The following papers were 

 read : — The specific heats of liquids, by Mr. H. Crompton. 

 When heat is applied to an unassociated liquid, there is an 

 increase in molecular kinetic energy, internal work is done 

 within each molecule, intermolecular attraction is diminished 

 and a small amount of external work is done. The first two 

 factors together make up the specific heat at constant volume. 

 The evaluation of the diminution of intermolecular attraction 

 is made by the author on the assumption that the total attraction 

 is equal to the difference between the latent heat of vaporisation 

 and the heat evolved when the vapour is compressed to the 

 volume it would occupy as a liquid but without undergoing this 

 change of state. Assuming that this attraction is zero at the 

 critical point and increases regularly with decrease of temper- 

 ature, its change with temperature is given by the expression 

 (L - RT log V/z>)/(T,, - T), where L is the latent heat, T,. and T 

 the absolute critical temperature and absolute.temperature respec- 

 tively, V and v the volumes of the vapour and liquid respectively. 

 Neglecting the fourth factor, viz., the external work done, the 

 author shows that the molecular heats of various liquids 

 for which the foregoing data are available agree fairly well 

 with those calculated by this method. — The constitution of 

 enolic benzoylcamphor, by Dr. M. O. Forster. It is shown 

 that this substance is probably phenylhydroxymethylenecamphor 

 from a consideration of the derivatives and decomposition pro- 

 ducts obtained from it. — Isomeric benzoyl derivatives from iso- 

 nitrosocamphor, by Dr. M. O. Forster. Two isomerides have 

 been obtained ; one crystallises in yellow prisms and melts at 

 105° ; the other is colourless, melts at 136 and does not give 

 isonitrosocamphor on hydrolysis. — Action of phosphorus 

 haloids on dihydroresorcins, by Drs. Crossley and Le Sueur. — 

 The absorption spectra of metallic nitrates, ii., by Prof. 

 Hartley. The positions of the characteristic absorption bands 

 depend upon the molecular weights of the salts in solution. The 

 characters of the spectra observed are equally well explained by 

 the assumption that partial ionic or partial hydrolytic dissoci- 

 ation occurs on solution. — The constitution of the products of 

 nitration of ;«-acetoluidide, by Dr. J. B. Cohen and II. D. 

 Dakin. — The action of metallic thiocyanates upon carbonyl 

 chloride, by Dr. A. E. Dixon. A description of the substituted 

 thiocarbimides obtained. 



Entomological Society, November 19. — The Rev. Canon 

 Fowler, president, in the chair. — Dr. Sharp, F.R.S., exhibited 

 the egg-cases made by a beetle of the genus Aspidomorpha (A. 

 pun, ticosta), and stated that they had been sent to him by Mr. 

 F. Muir, of Durban, Natal, where the beetle and the egg-cases 

 are common. — Dr. Norman H. Joy exhibited a well-marked 

 aberration of a female Lycaena icarus striped black on the 

 underside in the place of the usual ocellations ; a gynandro- 

 morphous specimen of the same species ; an aberration of a 

 male Lycaena bcllargus, similarly striped on the underside ; a 

 specimen ,of Everes argiades taken in 1S85 at Bournemouth ; 

 and specimens of Apatura iris from the neighbourhood of 

 Reading, taken from what appeared to be the throne of the 



NO. 1729, VOL. 67] 



ruling " Emperor" of the wood. Whenever another iris came 

 by, the one on the " throne " attacked it, and after a fight, in 

 which one would eventually pursue the other out of sight, 

 the victor returned to the perch. If this was captured, the next 

 iris coming along would take possession, and soon. — Mr. Claude 

 Morley exhibited a specimen of Diaitictus vulneratus, Sturm., 

 new to Great Britain, and a rare blue form of Miratora 

 vitellinae from Tuddenham Fen. — Mr. G. C. Champion 

 exhibited specimens of Nanophyges ditriiuri, Lucas, a beetle 

 from Central Spain, with drawings of the larva, pupa and 

 perfect insect. — Prof. E. B. Poulton, F. R.S., stated that Mr. 

 A. H. Church, of Jesus College, Oxford, had observed 

 the larva; of a species of Cucullia (probably C. verbasci), feed- 

 ing upon Buddleia globosa which was growing against a wall 

 in the Oxford Botanical Gardens. It is possible that the eggs 

 were laid upon the Buddleia because of the very rough general 

 resemblance in certain respects between its leaves and those of 

 Verbascum. Mr. R. McLachlan, F. R.S., mentioned the case of 

 Mamestra persicariae, at Lewisham, choosing Anemone japonica. 

 I le had offered them fern and elder (which is reputed a favourite 

 food), but the larvae refused everything except the original 

 anemone. Mr. Goss said that larvae of Choerocampa elpcnor, 

 taken at Weybridge from a species of American balsam, altcr- 

 wards refused willow herb, the usual food-plant of the species. 

 Prof. Poulton read a communication from Mr. G. F. Leigh 

 relating to the enemies of Lepidoptera in Natal. The very 

 common grey South African rat seems to be particularly fond 

 of almost any pupae, and will gnaw through thick wooden boxes 

 to get at them. They affect especially Choerocampa eson 

 and C. nerii. Even more remarkable than their keenness in 

 hunting pupa' is the way in which they capture moths on the 

 wing when feeding. Whilst flying at dusk, a rat would leap 

 from the roof right on to their food-plant, and more often than 

 not the moth selected for attack was captured. Bats are also 

 very destructive of South African insect-life. 



Ray Society, December 11. — Council Meeting. — Mr. John 

 Hopkinson, treasurer, in the chair. — A vote of condolence with 

 the widow and family of the late secretary of the Society, the 

 Rev. Dr. Wiltshire, was passed, and in his place Mr. Hopkinson 

 was elected secretary. The question of the appointment of 

 treasurer was not finally decided. 



Manchester. 



Literary and Philosophical Society, December 2. — Mr. 

 Charles Bailey, president, in the chair. — Mr. C. L. Barnes 

 showed a number of experiments depending on Hawksbee's 

 law, viz., that the pressure on the walls of a tube containing a 

 fluid is less when the fluid is in motion than when it is at rest. 

 Several of these are well known, e.g., the apparent attraction 

 which results when a current of air, radial or other, passes 

 between two parallel discs, and the suspension of a ball on a jet 

 of air or water. Other illustrations of the principle are that it 

 is impossible to blow a celluloid ball, or even an inflated toy 

 balloon, out of a funnel held in the ordinary upright position, 

 though, if the funnel be reversed, the ball or balloon can be 

 supported without difficulty. Also, if a couple of celluloid balls 

 are placed on a kind of railway made by lastening two rods to 

 one another, they cannot be separated by blowing between 

 them. The experiment of forcing a celluloid ball out of a tall 

 glass cylinder by blowing downwards upon it was also per- 

 formed, as were also several others of a similar character. — Mr. 

 Frank Southern exhibited and described a Japanese magic 

 mirror, and Dr. C. H. Lees showed a small piece of apparatus 

 used in the determination of the thermal conductivities of solids 

 over wide ranges of temperature. It consists in principle of a 

 differential hydrogen thermometer, one bulb of which is heated 

 by an electric current either in a flat strip of metal wound round 

 it or passing through the material of the bulb itself. 



Dublin. 

 Royal Dublin Society, November iS. — Prof. D. J. 

 Cunningham, F. R.S. , in the chair. — Prof. T. Johnson read a 

 paper on Phellomyces sclerotiophorus, Frank, a fungus of un- 

 known affinities which causes a form of scab in potato-tubers 

 and, in extreme cases, a dry rot. The author first observed 

 the fungus in several potato varieties, grown in the west and 

 other parts of Ireland, in the autumn of 1901. — Phellomyces 

 causes the formation of discoloured patches in the skin of the 



