May 13, 1922 



NA TURE 



629 



A Modified Octet Theory. 

 T N an interesting paper on electronic structures in 

 -^ unsaturated molecules, published in the Journal 

 of the American Chemical Society for March, Mr. E. D. 

 Eastman discusses multiple bonds in relation to the 

 octet theory of atomic structure due to G. N. Lewis. 

 It is assumed that the pair of electrons possessed by 

 dements of the first period (except hydrogen), 

 although usually not acting as valency electrons, 

 and forming a shell persisting throughout the entire 

 period of elements, may take part in the forma- 

 tion of outer groups of octets when it is otherwise 

 difficult for these to be formed. The double bond is 

 then pictured as one atom in which the central 

 electrons have been drawn into the outer octet, joined 

 by two electrons to another atom in which the normal 

 arrangement is preserved. In cases of triple bonding 

 the two inner electrons are assumed to have been 

 drawn into the outer shell of tw^o adjacent atoms, 

 there being again two electrons held in common. 



The arrangements are illustrated by the formulae 

 of ethane, ethylene, and acetylene, in which the 

 symbols indicate nuclei and all outer electrons are 

 shown as dots : — 



Multiple bonds are apparently formed only by ele- 

 ments of the first period. 



To meet the requirements of facts relating to 

 stability, reactivity, and free rotation, the electrons 

 of unsaturated octets are assumed to be held in 

 equilibrium positions at greater distances from the 

 nucleus than in the ordinary case, the transfer from 

 the extended position to the usual ones liberating 

 energy. No attractive force between electrons is 

 assumed, and the electronic arrangement is taken as 

 cubic, though subject to distortion. The structure 

 of carbon dioxide is probably unsymmetrical, rather 

 than the arrangement of three nuclei in line commonly 

 assumed. The structures of the nitrogen and oxygen 

 molecules are represented by the following symbols ; — 



: N : N : and -..'o-.O: 



Many chemical facts discussed in the paper should 

 prove of interest to chemists, who cannot ignore 

 the undoubted difficulties introduced by multiple 

 bonds in the present theory of molecular structure. 



University and Educational Intelligence. 



Bristol. — The Vincent Stuckey-Lean scholarship 

 in botany, tenable for one year and value 36/. with 

 free access to the department . of botany, is offered. 

 Further information may be obtained from the 

 Registrar, the University, Bristol. Applications for 

 the scholarship must be received not later than 

 Saturday, May 20. 



London. — The following lectures, which will be 

 open to the public free and without ticket, have been 

 arranged : — At King's College, a course of three lectures 

 on Tertiary Igneous Action in Britain, by Dr. Alfred 

 Harker, on May 17 and 31 at 5 o'clock, and on May 

 24 at 4 o'clock, a course of four lectures on The 

 Development of the Head Muscles of Vertebrates, 

 by Prof. F. H. Edgeworth, at 5.30 p.m., on May 22-25, 

 and one lecture by Prof. J. F. Van Bemmelen, of the 

 University of Groningen, on The Morphological 

 Character of the Skin Pattern in Insects and Mammals, 



on May 17 at 5.30 p.m. At Birkbeck College, a 

 course of three lectures on Recent Work with regard 

 to the Influence of Soil Conditions on Agriculture, 

 by Dr. E. J. Russell, on Fridays, commencing May 12 

 at 6 o'clock, and one lecture on Whorled Phyllotaxis, 

 by Prof. J. C. Schoute of the University of Groningen, 

 on May 11 at 5.30 p.m. At the School of Oriental 

 Studies, a course of three lectures on The Idea of 

 Personality in Sufism, by Dr. R. A. Nicholson, on 

 Wednesdays, commencing May 17 at 5 o'clock. At 

 the London School of Economics two lectures on 

 Modern Views of Indo-European Origin, by Dr. Peter 

 Giles, on Fridays, commencing May 12 at 5 o'clock. 



The following advanced lectures in medicine will 

 be given in French at the Rooms of the Royal Society 

 of Medicine, i Wimpole Street, W i, at 5 p.m.: on 

 May 22, " Anti-ana^phylaxie," by Prof. F. Widal ; 

 on May 25, " De I'Erythr^mie, (Maladie de Vaquez- 

 Osler)," by Prof. H. Vaquez ; and on May 31, " Des 

 reflexes de defense," by Prof. J. Babinski. 



Mr. W. H. Reed, a former mayor of the city of 

 Exeter, has purchased and presented to the Governors 

 of the University College, Exeter, the mansion house 

 of Streatham Hall and part of the Streatham Hall 

 estate, to be used as the site of the University College 

 of the South-west of England. The Governors have 

 purchased the adjoining farm and lands so that the 

 new College will enter into possession of a site of 

 120 acres. It is expected that the incorporation of 

 the new University College, the establishment of 

 which has been approved by the University Grants 

 Committee, will be effected this summer. Streatham 

 Hall is placed on rising ground to the north-west of 

 the city. It is near the stations and conveniently 

 situated in every respect. The estate is admirably 

 laid out and commands a prospect over the Exe 

 valley to Dartmoor. It is intended to place on the 

 new site not only the College buildings but also the 

 hostels and playing fields. 



A conference of representatives of universities 

 of Great Britain and Ireland will (as we announced 

 last week) .be held at University College, London, 

 on Saturday, May 13. The holding of such annual 

 conference was resolved upon at the First Congress 

 of the Universities of the British Empire, but, owing 

 to the war, the realisation of this project was post- 

 poned although conferences for special purposes were 

 held in the years 1917-1920. At the Second Congress 

 of Universities of the Empire in 1921 the resolution 

 in favour of annual conferences was re-affirmed and 

 it was decided that the month of May would be a 

 convenient time for holding them. All the home 

 universities were invited to suggest agenda and from 

 these suggestions the Standing Committee of Vice- 

 Chancellors selected the subjects which appeared to 

 be most suitable for discussion at the present time, 

 namely, the urgent need for the provision of enlarged 

 opportunities for advanced study and research in 

 British universities, the increase of residential 

 accommodation for students, specialisation in certain 

 subjects by certain universities, and organisation of 

 adult education as an integral part of the work of 

 the universities. 



The Report of its Principal Officer on the work of 

 the University of London during 1921-22 gives the 

 following among other statistics for the three years 

 1913-14, 1920-2.1, 1921-22 : total admissions of 

 students, 3852, 6728, 7092 ; candidatas for examina- 

 tions (final) for degrees — 1807, 1746, 2455 (external 

 candidates only — 907, 710, 912) ; names on the roll 

 of internal students on May i, 4888, 7870, 8758. 



NO. 2741, VOL. 109] 



