bluuebunny/crossref_metadata_2025 huggingface dataset:
Alan Marmaduke Wetherell. 31 December 1932 — 13 September 1998
Authors: Allaby James V.
Published: December 2006

Alan Marmaduke Wetherell was a physicist of repute. During his career he excelled in the practice of his profession. As a research student he showed great promise at the University of Liverpool, where he conducted his doctoral work in the group of Professor James Macdonald Cassels from 1954 to 1957. He went on to write his thesis on the ratio of radiative to mesic capture of stopped negative pions by hydrogen. He continued in his research group doing experiments on polarized muon beams and on the radiative β-decay of the pion. In 1957 he was awarded a Commonwealth Fund Fellowship, which he used to visit the California Institute of Technology, where he worked on the photoproduction of kaons and pions. In 1959 he moved from California to Switzerland, where he joined the European Organization for Nuclear Research (CERN). He rose to become a senior research physicist in 1963 and was appointed the Division Leader of the Experimental Physics Division in 1981-84. He retired from the CERN staff in December 1997.
Sir Clifford Charles Butler. 20 May 1922 – 30 June 1999
Authors: Butterworth Ian
Published: December 2006

Clifford Butler was born in Earley, Reading, on 20 May 1922 to Charles and Olive Butler. An only child, he went to Reading School in 1932, having won a Berkshire County Council Educational Scholarship worth £15 per year. In addition to his academic work he was active in the Scouts and was a House Prefect (East House). Leaving school he went to Reading University to take physics, as did Kathleen Collins, whom he was to marry in 1947. Graduating in 1942 with a first–class BSc (Special) he stayed on as a demonstrator, his National Service taking the form of teaching radio as part of the State scheme to produce radar physicists, and acted part–time as a physicist at the Royal Berkshire Hospital. Kathleen went to work at the Road Research Laboratory. Butler found time, largely in the evenings, to undertake research for a PhD in electronic diffraction in the laboratory of Professor J.A. Crowther. He worked very closely with his thesis supervisor Dr Tom Rymer and it was there that he started to demonstrate his considerable skills in technical matters. His thesis, ‘some factors affecting precise measurement in electron diffraction’, was presented in April 1946 and was a detailed study, covering both technical and theoretical aspects, of how to improve the use of Debye–Scherrer electron–diffraction photographs to investigate crystal structure. The research on which it was based initiated four very different papers and led Crowther to predict, immediately after Butler's PhD examination, the latter's Fellowship of The Royal Society.
Sir Christopher Sydney Cockerell, C.B.E., R.D.I. 4 June 1910 — 1 June 1999
Authors: Wheeler Raymond L.
Published: December 2006

Christopher Sydney Cockerell was born in Cambridge on 4 June 1910. His father, Sir Sydney Carlyle Cockerell, was at that time Director of the Fitzwilliam Museum at Cambridge, a position he was to hold for nearly 30 years. He had formerly been secretary to William Morris and the Kelmscott Press. His mother was a talented artist known for her superb illuminated manuscripts. Christopher was an only son, with two sisters. His distinguished father's very strong personality made early relationships with him rather difficult. Fortunately he adored his mother, who had a profound influence on him. The Cockerell household entertained many distinguished visitors such as George Bernard Shaw, Joseph Conrad, Thomas Hardy, Freya Stark and Siegfried Sassoon. Sir Sydney was very disappointed when Christopher showed very little interest in literature, public affairs and other aesthetic pursuits of such visitors. It was only when T.E. Lawrence stayed at their home that he showed an interest—this was in Lawrence's 1000 cc Brough Superior motorcycle, which caused his father to remark that Christopher was ‘no better than a garage hand’ (Blunt 1964).
David George Crighton. 15 November 1942 – 12 April 2000
Authors: Huppert Herbert E. , Peake Nigel
Published: December 2006

For the last decade of his life, David Crighton was the undisputed leader of the applied mathematics community in Britain. He made penetrating research contributions to the subject of aeroacoustics, which involves the emission and control of aircraft and engine noise, to our understanding of the propagation and evolution of linear and nonlinear waves and to the excitation of structural vibrations. He was a widely respected scientific administrator, working imaginatively as the chairman or president of many national and international committees. He was the enlightened editor of prestigious international journals and founded a series of texts in applied mathematics. At the time of his death from cancer at the tragically early age of 57, he was in addition filling with distinction the roles of a visionary department head and a much loved Master of Jesus College, Cambridge.Despite these heavy administrative burdens and his research schedule, David exuded warmth, gregariousness and a selfless interest in the careers of others. He seemed to have unlimited amounts of time to help and motivate his colleagues. He also found time to run regularly and to develop his prodigious knowledge of music, particularly the works of Wagner, on whose operas he was an international authority.
Leslie Crombie. 10 June 1923 — 3 August 1999
Authors: Pattenden Gerald
Published: December 2006

Leslie Crombie was born in York on 10 June 1923, the second eldest, and only boy, of Walter Crombie and Gladys (née Clarkson). On his father's side his great-grandfather had kept a tobacconist shop in York and his grandfather, George, had founded a prosperous legal practice in the City of York. On his mother's side, Leslie's great–grandfather originated from London and settled in York after helping to build the York Railway Station. Leslie's father qualified as a solicitor and practised law in his grandfather George's office. However, he disliked the profession and, after his marriage and the death of his father, Walter passed over the practice to his brother Norman and took the lease of a hotel in the Isle of Wight. Unfortunately, the hotel did not prosper and was given up after a few years, and the family, which included Leslie's three sisters, Ivy, June and Molly, moved to Portsmouth. Although Leslie's father had a small allowance from his brother Norman and the legal practice in York, and he had various small intermittent incomes from teaching, the family was desperately poor during the 1930s. Leslie received little encouragement from his parents, but he passed the 11+ examination and entered Portsmouth Northern Grammar School in 1934, where he was awarded a very respectable School Certificate when he was 16 years old. However, it was now 1939 and World War II was about to start, and his school was evacuated to Winchester. With poor living conditions and little facilities for study, the young Leslie was determined to take a job and study part-time. He was appointed in 1940 as an assistant in the analytical laboratory of Timothy Whites and Taylor at their head office in Portsmouth under the supervision of Ron Gillham, who greatly influenced his further career; he was paid 13 shillings and 6 pence (in decimal terms, 67½pence) per week. In the evenings, Leslie studied at Portsmouth Municipal College for a London University Intermediate BSc. Alas, after a heavy bombing raid in January 1941, Timothy Whites and Taylor's laboratories were removed from the map, along with a great deal of the centre of Portsmouth—but fortunately not the MunicipalCollege.
Kenichi Fukui. 4 October 1918 — 9 January 1998
Authors: Buckingham A.D. , Nakatsuji H.
Published: December 2006

Kenichi Fukui was born in Oshikuma, Nara, Japan, on 4 October 1918. He was the eldest of three boys of Ryoukichi, his father, and Chie, whose family name before marriage was Sugisawa. Ryoukichi Fukui, who graduated from the Tokyo Commercial Institute (later Hitotsubashi University), was a merchant who traded with foreign countries and also managed a factory making precision instruments. He liked fishing and often took Kenichi with him, and was a member of the National Geographic Society—the National Geographic Magazine was one of the most important magazines of Kenichi's childhood. Chie graduated from Nara Women's College and was an affectionate mother of her boys. She never forced them to study but provided a studious environment. For example, she bought for her children the complete works of Souseki Natsume, a famous Japanese novelist, whose books Kenichi was very fond of reading.
Hendrik Christoffel Van De Hulst Ridder In De Orde Van Nederlandse Leeuw. 19 November 1918 – 31 July 2000
Authors: Cook Alan
Published: December 2006

The Netherlands, a small country, has been particularly rich in astronomers in the twentieth century, and Hendrik van de Hulst was among the most notable. He is distinguished for three far–reaching contributions to our knowledge of the Cosmos. As a graduate student he predicted that the hyperfine transition at 1420 MHz in atomic hydrogen (the 21 cm line) would be observable, and later participated in its discovery and early exploitation. He guided Dutch and European space research and its organization from the beginnings. Throughout his entire career he developed the theory of the scattering of radiation by small particles. He was consequently called on to be a member or chairman of important national and international committees, and his contributions, to the advancement of knowledge and effective organization alike, have been recognized by numerous awards and distinctions.
Oliver Louis Zangwill. 29 October 1913 – 12 October 1987
Authors: Gregory Richard L.
Published: December 2006

Oliver Zangwill was the Disraeli of psychology. He came from a distinguished, unusually interesting family, and was literary with sophisticated political skills. Oliver's father was the influential novelist and dramatist Israel Zangwill (1864–1926), whose writings include Children of the ghetto and The master. Evidently a formidable character, Oliver confessed to me that his father was the only person in his life that he had truly feared. Oliver was 12 when his father died. His mother, born Edith Ayrton, was an early woman doctor (examined for her doctorate by Paul Broca, in Paris), becoming involved in politics and active in the establishment and running of the League of Nations. She spoke Japanese and translated fairy tales.
Maurice Stevenson Bartlett. 18 June 1910 — 8 January 2002
Authors: Whittle Peter
Published: December 2006

The last 70 years or so have seen the vigorous development of mathematical models in technology, epidemiology, economics and the natural sciences whose dynamics are intrinsically random in some sense; life is such. The study of the behaviour such models might demonstrate is that of stochastic processes. The converse task, to determine an appropriate model from reallife behaviour, is that of statistical inference.Maurice Bartlett was a pioneer in these disciplines whose insight and power as a problemsolver brought him an international reputation. He made basic advances in the study of stochastic models and the statistical analysis of data that they might represent, in particular for models with a dynamic element, so allowing the study of phenomena that evolve in time. Specifically, he made early key advances in what is now called multivariate analysis, developed time series analysis, produced a coherent theory of stochastic processes (making innovations whose significance was recognized only years later) and studied stochastic models of, for example, the growth of population, the course of epidemics, and systems with a spatial dimension (such as vegetation or meteorological variables). A much less tangible phenomenon which never lost its fascination for him concerned methods for the identification of ‘factors’ in psychology or performance. These are just the major headings in a series of investigations in which he simultaneously developed stochastic theory, evolved statistical methodology and pursued the particular application to a conclusion.As well as enjoying a unique reputation among his colleagues, Bartlett, although an undemonstrative man, evoked a lasting warmth and firm loyalty in all who worked with him.
Roger Michael Needham CBE FREng. 9 February 1935 – 1 March 2003
Authors: Hoare Tony , Wilkes Maurice V.
Published: December 2006

Roger Needham was born in Sheffield on 9 February 1935. He was the only son of Leonard William Needham and Phyllis Mary Needham (née Baker). Leonard and Phyllis had met in the first year chemical laboratory at Birmingham University and had duly graduated in that subject. At the time of Roger's birth, Leonard was a lecturer in the Mining Department at Birmingham, having become in effect a chemical engineer. When Roger was two years old the family moved to Sheffield, where Leonard took up an appointment with a company that made mineral separation plants, in which particles of coal were separated from lighter particles of incombustible material by flotation in a dense medium of suspended barytes.
Walter Thompson Welford. 31 August 1916 — 18 September 1990
Authors: Barnett Michael , Smith Robin
Published: December 2006

Walter Thompson Welford (Walter Weinstein until 1957), born in London, left Hackney Technical Institute at the age of 16 years to become a technician at the London Hospital and later at Oxford University Biochemistry Department. In 1942, after obtaining a first–class honours external degree in mathematics from London University by private study, he returned to London to work at Adam Hilger Ltd. He moved to Imperial College, London, as a research assistant in 1947, became a lecturer in 1951, a senior lecturer in 1959, Reader in 1964 and Professor of Physics in 1973. He was elected a Fellow of The Royal Society in 1980. After formal retirement in 1983 he continued to be research active at Imperial College and the University of Chicago until his death from throat cancer in 1990.Walter's scientific work was in the craft of optical instrumentation, in which he became an internationally recognized master. His contributions ranged from basic aberration theory to the design, construction and testing of a vast range of optical instrumentation. His research fields were principally lens aberrations, optical microscopy, bubble chamber optics, laser speckle, non–imaging optics, diffraction gratings and diffractive lenses. Many will also remember him as a kindly and inspiring educator.
Exogenous re-infection and the dynamics of tuberculosis epidemics: local effects in a network model of transmission
Authors: Cohen Ted , Colijn Caroline , Finklea Bryson , Murray Megan
Published: December 2006

Infection with
Mycobacterium tuberculosis
leads to tuberculosis (TB) disease by one of the three possible routes: primary progression after a recent infection; re-activation of a latent infection; or exogenous re-infection of a previously infected individual. Recent studies show that optimal TB control strategies may vary depending on the predominant route to disease in a specific population. It is therefore important for public health policy makers to understand the relative frequency of each type of TB within specific epidemiological scenarios. Although molecular epidemiologic tools have been used to estimate the relative contribution of recent transmission and re-activation to the burden of TB disease, it is not possible to use these techniques to distinguish between primary disease and re-infection on a population level. Current estimates of the contribution of re-infection therefore rely on mathematical models which identify the parameters most consistent with epidemiological data; these studies find that exogenous re-infection is important only when TB incidence is high. A basic assumption of these models is that people in a population are all equally likely to come into contact with an infectious case. However, theoretical studies demonstrate that the social and spatial structure can strongly influence the dynamics of infectious disease transmission. Here, we use a network model of TB transmission to evaluate the impact of non-homogeneous mixing on the relative contribution of re-infection over realistic epidemic trajectories. In contrast to the findings of previous models, our results suggest that re-infection may be important in communities where the average disease incidence is moderate or low as the force of infection can be unevenly distributed in the population. These results have important implications for the development of TB control strategies.
On sun-spot periodicities. —Preliminary notice
Authors: Schuster Arthur
Published: December 2006

In cases where it is necessary to separate true periodic changes from other variations, which during short periods of time often simulate periodicities, the method of the periodogram is at present the only one which can give definite results. In view of the importance of the questions connected with the changes in the frequency of the sun-spots, I have, therefore, undertaken the considerable labour of forming a complete periodogram of sun-spot variability as far as the data at my disposal allow me to do so. The following is a brief abstract of the results; the investigation will be presented shortly:— The periodogram, as already explained, is the diagram representing the intensity of periodic variations as determined from the sum of the squares of the two Fourier coefficients belonging to each assumed period. This diagram represents for any regular or irregular change exactly what the energy diagram gives us for a luminous disturbance which is analysed by a spectroscope.
The lunar tide in the Earth's atmosphere
Authors: Chapman Sydney
Published: December 2006

1―This paper briefly summarizes the present state of our knowledge of the lunar tide in our atmosphere. It does this mainly by means of three diagrams, figs. 1, 2, and 4; figs. 2 and 4 are of novel type, while fig. 1 corrects and brings up to date, by the addition of much new material, a diagram published in my presidential address to the London Mathematical Society. 2―The lunar atmospheric tide, though of small amplitude, is of considerable theoretical interest; it presents several important unsolved problems. It was first sought for about 1774, by analysis of barometric data (for Brest) by Laplace, but with inadequate material. It was first determined in 1842 by Lefroy, for St. Helena, and a few years later by Elliot, for Singapore. Successive directors of the Batavia observatory later determined the tide from long series of their observations. All these are tropical stations, where the tide has its largest amplitude, and where the other barometic changes, from which the tide has to be disentangled by computation, are less than in higher latitudes.
The spectrum of ionized tellurium—Te III
Authors: Krishnamurty S. G.
Published: December 2006

Following the investigations in this laboratory on the successive spectra of selenium, an extensive research has been carried out by the author during the last two years on the spectrum of tellurium belonging to the same group of the periodic table. Of the various characteristic spectra of this element, the analysis of only those due to the neutral and the more highly ionized atom (Te IV, V, VI, and VII) is at present known. Owing perhaps to the very complicated nature of the spark spectrum of tellurium in the ordinary region, the values of the atomic energy states of Te II and Te III have yet remained undetermined. Our knowledge of the spectral structures of selenium together with that of tin and antimony, published recently, has considerably facilitated the work on tellurium, and it is the purpose of the present paper to record in detail the structure of the spectrum of the doubly-ionized atom, a preliminary report of which appeared in 'Nature.' ExperimentalThe important super-mutliplets resulting from a transition of the 6
p
, 5
d
, and the higher states to the 6
s
state of Te III are expected to lie in the ordinary visible and quartz regions. For an investigation of these regions two sets of plates have been taken; one set with small-dispersion instruments such as Hilger's constant deviation and E
2
quartz spectrographs and a Fuess glass instrument. These plates served well fro a qualitative study of the spectrum, particularly in the course of the assignment of the lines to the respective states of ionization of the atom. For such a preliminary study, various sources have been employed consisting of sparks in air and in an atmosphere of nitrogen and hydrogen at different pressures. Unlike selenium, metallic sticks of tellurium could be use directly as terminals between which the sparks were produced.
Calcium sulphate hemihydrate and the anhydrites I-Crystallography
Authors: Caspari W. A.
Published: December 2006

An extensive literature has grown around the subject of calcium sulphate, embracing work prompted not only by the technical importance of plaster of Paris but also by the peculiar inter-relations between the several forms of calcium sulphate. The dihydrated salt (gypsum, selenite) and the orthorhombic anhydrous salt (anhydrite) have long been known as common minerals and their chemical and crystallographic characters are well established. About the hemihydrate (plaster of Paris) and the active, hard-setting anhydrous modification (soluble anhydrite), which do not occur in nature, there is less certainty. Agreement has so far not been reached upon these substances as crystal species, nor yet upon the nature of the changes by which they pass one into another and into the stabler modifications. Conflicting statements are, moreover, to be found in the literature as to whether there are polymorphs of each of the above-named substances, and if so, how many. The Hemihydrate Crystal Since the substances was first isolated in the form of prismatic crystals, not exhaustively examined, various authors have prepared and described crystalline hemihydrate. This latter may be obtained either by protracted contact of the solid dihydrate with hot acid or saline solutions, or by crystallization, at temperatures well above the ordinary, out of solutions or calcium sulphate in moderately concentrated hydrochloric or nitric acid. The crystal has variously been assigned to all the known systems except the cubic and the tetragonal; but there is unanimity to the effect that it is of acicular habit and consists of six-sided prisms. The crystals observed appear for the most part to have been of microscopic size. Recently, however, Onorato and Gallitelli have dealt with crystals large enough for goniometric and X-ray investigations, and to the latter, especially, we owe a thorough study of the crystal and its structure. Both authors consider the crystal to be monoclinic, the former finding
a
= 12·07 A,
c
= 6·40, β = 92°,
z
= 6; the latter
a
= 11·94,
b
= 6·83,
c
= 12·70, β = 89° 24´,
z
= 12. Now for the monoclinic system the number of molecules Z per unit cell is normally 2, 4, or 8, and such Z numbers as 6 and 12 could only be accounted for by somewhat improbable hypotheses. A re-examination of the crystal has therefore seemed desirable.
The electronic structure of some polyenes and aromatic molecules IV-The nature of the links of certain free radicals.
Authors: Coulson Charles Alfred
Published: December 2006

In the first two papers of this series (1937a, b), referred to as I, II, Lennard-Jones has developed a method for investigating the lengths and energies of the links in some unsaturated molecules. For this purpose he used the method of molecular orbitals. In paper III (1937), Penney obtained similar results, using the electron-pair methods of resonance, developed Pauling and others. It is the purpose of the present paper to extend the calculations to chain molecules and radicals in which the number of carbon atom s is odd, an d in which, therefore, there is one electron which does not form a bond, in the usual picture of the chemist. We shall use the method of molecular orbitals, and this work may be said to be a continuation of I and II. The writer would like to than k Professor Lennard-Jones for suggesting this work, and for the opportunity of discussing it with him during the calculations. In general these free radicals with “trivalent” carbon are not stable, and tend to form dimers; but there are certain of them which do exist either as stable substances or in dissociative equilibrium with their dimers. Hückel (1935) has discussed these radicals, on the earlier form of the theory in which all the links were assumed equal and no allowance was made for their compression. His work needs to be extended because there is no reason why the links should be all equal, and in fact, the bond diagrams of the chemist lead one to suspect otherwise, and to believe that there may be one of the carbon atoms (the one on which the unpaired electron is to be found) different from the others (for which all the electrons are paired). On the molecular orbital theory, in which each electron is supposed free to move throughout the whole molecule in an averaged potential field, it is not so easy to see a t once in what way the presence of the odd electron will alter the arrangement of the links. So the first question that we shall ask will be whether in chain molecules, such as C2n+1H2n+3, there is one carbon atom occupying an essentially different situation from all the others. We shall then compute the resonance energy.
Relaxtion methods applied to engineering problems II. Basic theory, with application to surveying and to electrical networks, and an extension to gyrostatic systems.
Authors: Black A. N.
Published: December 2006

1. The “Method of Systematic Relaxation of Constraints” was devised for the determination of stresses in frameworks,—that is in elastic structures having the characteristic that a strained configuration can be specified by attaching values to a
finite
number of co-ordinates. Recently it has been extended to continuous systems (e. g. beams) on the understanding that a finite number of co-ordinates will define a configuration for practical purposes, though not from a mathematical standpoint. So far the power of the method has been exhibited only in relation to elastic problems: in these its results appear to converge rapidly, judged by a few examples of which the exact solutions were known. The aim of the present paper is fourfold, viz. (1) to prove that relaxation methods, applied systematically to problems of elastic equilibrium, give solutions which converge steadily towards exact results; and hence, by analogy, (2) to show that they are applicable to any “minimal” problem, e. g. the adjustment of errors according to the method of least squares; (3) to notice, as particular examples, the adjustment of errors in level or triangulation surveys, and the partition of electric current in non-inductive networks of conductors; and (4) to discuss the more difficult problem of an inductive network carrying alternating current. This serves as a simple illustration of systems which are governed by equations containing “gyrostatic” or “non-energetic” terms, and which for that reason do not present minimal problems of the usual kind.
Statistical mechanics of the adsorption of gases at solid surfaces
Authors: Wilkins F. J.
Published: December 2006

The object of this paper is to develop a statistical mechanical treatment of adsorption of gases on plane solid surfaces using the method of partition functions. Several authors have approached this problem by way of the Boltzmann equation but without success. In fact Kruyt and Moddermann (1930), who discuss this work in some detail, conclude that the equation cannot be satisfactorily applied to the problem of gaseous adsorption at a solid surface and suggest that this is because the forces causing adsorption are of a chemical nature. Recently, Fowler (1936
a
) has developed the Langmuir isotherm using essentially Langmuir’s assumption of chemisorption on an adsorbing surface similar to a chequer board containing a fixed number of points of adsorption, and further the assumption that if a molecule is adsorbed on one point it does not influence adsorption on contiguous points. This further assumption is relaxed in later papers (Fowler 1936
b
; Peierls 1936). The assumption made by Langmuir that adsorption forces are chemical in nature is not always true, as it is likely that the forces operative are in many cases of the van der Waals’ type. His other assumptions are unnecessarily restrictive in view of the considerable amount of evidence on lateral mobility in the adsorbed layer and also of the certainty that molecules adsorbed contiguously suffer the normal molecular interactions of the van der Waals’ type.
Critical phenomena in gases. II. Vapour pressures and boiling points
Authors: Lennard-Jones John Edward , Devonshire A. F.
Published: December 2006

The object of the first paper on “Critical Phenomena in Gases” (referred to in this paper as Paper I) was to develop a simple method of dealing with dense gases and to calculate critical temperatures in terms of atomic fields of force. Each atom in a dense gas was pictured as caged for most of its time by a cluster of neighbours, equal in number to those which surround it in the solid (and presumably also in the liquid) phase. The model was intended to provide a general average of the potential field in which any one atom moved by replacing its varying environment by an arrangement of neighbours which could be regarded as typical. This arrangement was taken to be the one in which the neighbours were situated at their mean positions as determined by the density of the gas. The potential energy of any one atom could thus be expressed as a function of the volume of the gas—a step which is probably the crucial one in a theory of critical phenomena. This point of view brings the process of condensation within the category of those described by Fowler (1936) as
co-operative
phenomena. In passing we may observe that the derivation of van der Waals’ equation provides a particular example of this method, for in it the potential energy of each atom is assumed to be inversely proportional to the volume. The present theory goes beyond this simple model, for the potential energy of an atom is considered to be not only a function of volume but also a function of the position of the atom relative to its neighbours. The probability of finding an atom in any assigned position can be calculated by statistical means and its average potential energy and its available free volume easily deduced. The equation of state can then be deduced by thermodynamic methods, as has been pointed out elsewhere (Lennard-Jones 1937).
The infra-red absorption spectrum of methylene chloride
Authors: Corin C. , Sutherland Gordon Brims Black Mcivor
Published: December 2006

The absorption spectrum of methylene chloride has been studied over limited regions in the infra-red by several workers (Ellis 1926; Lecomte 1933; Corin 1936; Emschwiller and Lecomte 1937). So far as we are aware it has never been investigated between 2-5 and 7μ, although this is a very important region. The present paper describes a study of the absorption of this substance in the liquid state between 2 and 12μ, which was undertaken with the following objects in view. First, it was hoped that it might be possible to resolve certain difficulties in the correlation of the infra-red with the Raman spectrum of this molecule. Thus Trumpy (1934) from a very careful examination of the Raman spectrum had made an assignment of the nine fundamental frequencies which did not admit of a reasonable explanation of a very strong absorption observed in the infra-red by Lecomte (1933) near 8μ. Before any reinterpretation of existing data could be attempted it was obviously necessary to complete the map of the spectrum between 2∙5 and 7μand to confirm Lecomte’s work at 8μIt was also important to observe as many overtone and combination bands as possible to provide data for verifying and testing any new assignment of the fundamental frequencies. Secondly, it was chosen as a suitable molecule for the further study of the assumption of independent groups (Sutherland and Dennison 1935; Mecke 1932) in computing the frequencies of a polyatomic molecule from a simplified but still very general potential function. Thus it is well known that certain groups (such as CH2or CH3) in a molecule give rise to certain characteristic frequencies in the infra-red and Raman spectra of these molecules, being apparently practically in­dependent of the rest of the molecule. Such frequencies are easy to identify in analysing the vibration spectrum of a polyatomic molecule but the frequencies which arise from the vibrations of those semi-independent groups as wholes are not at all easy to assign and it is just those “inter­-group” frequencies as opposed to the “intra-group” frequencies for which we have found a new method of treatment in this case. Yet the method which depends on an application of the isotope effect, is a very general one and should be applicable to many classes of polyatomic molecules.
On the time required for diffusion and its relation to processes in muscle
Authors: Hill Archibald Vivian
Published: December 2006

Two problems of diffusion are considered in relation to muscle: (A) How rapidly can chemical changes occurring inside a muscle be detected and measured outside by some device (e. g. an electrode) specifically sensitive to one of the products capable of diffusing out? (B) If, as seems probable, the process of excitation is limited to the surface of a fibre, could diffusion be rapid enough for contraction to be propagated inwards by the arrival at each point of some chemical substance liberated at the surface? As regards (A), it is shown that an indication of chemical change can be given rapidly if the layers of tissue and fluid between muscle fibres and recording surface are kept thin, but that the attainment of final equilibrium is too slow to allow accurate following of changes occurring at all quickly, unless the layers of tissue and fluid are reduced to a few microns in thickness. As regards (B), it is shown that if the twitch of a muscle fibre is assumed to involve the contraction of the whole of its contents, diffusion from the outer surface could not be fast enough to account for observed speeds of contraction. If, however, in a twitch the outer region only, say one-half of the fibre, were involved, which agrees with the known fact that the ratio of twitch tension to tetanus tension is usually considerably less than unity, then diffusion over the shorter distances involved would be amply quick enough. The considerable difference between the temperature coefficients of the rates of diffusion and contraction shows that the time course of contraction cannot be determined by diffusion. The times calculated for diffusion, however, are short enough to allow us to suppose, if we wish, that the contractile process begins at any point when the concentration there of some hypothetical substance liberated at the surface during excitation, and diffusing inwards, reaches a critical value. The connexion between excitation and contraction is discussed.
The electrical properties of the muscle fibre membrane
Authors: Katz Bernard , Hill Archibald Vivian
Published: December 2006

An analysis is made of the electric properties of frog muscle using the ‘rectangular pulse’ technique of Hodgkin & Rushton (1946). The experiments were made on isolated fibres and small bundles of the M. adductor magnus and on the M. extensor longus dig. IV. Sub-threshold currents of about 0.1 sec. duration were applied and wave form and attenuation of the extrapolar potential changes determined. In the vicinity of the cathode the relation between current and voltage across the fibre membrane is non-linear, and there is evidence of a local electric response with currents of more than 30% threshold strength. At the anode, however, the membrane behaves as a con­ductor of approximately constant resistance (§ A). At an average temperature of 22°C, the following mean values were obtained: (
a
) Fibre diameter: 75
μ
in the bundles of M. adductor magnus, and 45
μ
in M. extensor longus dig. IV. (
b
) Characteristic length of the muscle fibres: 0.65 and 1.1 mm. respectively. (
c
) Membrane time constant: 9 and 18.5 msec. (
d
) Specific resistance of the myoplasm: about 230 Ωcm. (
e
) Transverse resistance of the fibre membrane: 1500 and 4300 Ωcm.
2
. (
f
) Membrane capacity: about 5
μ
F/cm.
2
. The numerical differences between isolated fibres and whole muscle arose chiefly from a different value of the membrane resistance, the significance of which is discussed (§§ B1 and D). The value of the membrane capacity of muscle is about five times higher than that re­ported for various other cell membranes and confirmed here for isolated crustacean nerve fibres. The large membrane capacity must be an important factor in determining the slow electrical time scale of muscle. The relations between the electric constants of the resting muscle fibre and some of its physiological properties (time factor of excitation, propagation velocity, rate of decline of the end-plate potential) are discussed (§E). The location of the membrane, or interface, at which electromotive changes occur is discussed, and a number of reasons are given which indicate that the site of the electrotonic potential changes must be at the surface of the muscle fibres.
Tag-based indirect reciprocity by incomplete social information
Authors: Masuda Naoki , Ohtsuki Hisashi
Published: December 2006

Evolution of altruistic behaviour in interacting individuals is accounted for by, for example, kin selection, direct reciprocity, spatially limited interaction and indirect reciprocity. Real social agents, particularly humans, often take actions based on similarity between themselves and others. Although tag-based indirect reciprocity in which altruism occurs exclusively among similar flocks is a natural expectation, its mechanism has not really been established. We propose a model of tag-based indirect reciprocity by assuming that each player may note strategies of others. We show that tag-based altruism can evolve to eradicate other strategies, including unconditional defectors for various initial strategy configurations and parameter sets. A prerequisite for altruism is that the strategy is sometimes, but not always, visible to others. Without visibility of strategies, policing does not take place and defection is optimal. With perfect visibility, what a player does is always witnessed by others and cooperation is optimal. In the intermediate regime, discriminators based on tag proximity, rather than mixture of generous players and defectors, are most likely to evolve. In this situation, altruism is realized based on homophily in which players are exclusively good to similar others.
Research conducted for the medical department of the privy council at the pathological laboratory of St. Thomas's Hospital. First series.—The chemical nature and composition, combinations, and metamorphoses of the colouring-matters of bile
Authors: Thudichum J. L. W. , Simon John
Published: December 2006

I.
On Choiophphæine or Bilirubine and its Compounds
. Sect. 1. The paper commences with a short historical retrospect on the literature of the subject under consideration, in which the researches of Berzelius, Scherer, Hein, Marchand, Heintz, Maly, and Städeler are mentioned. Sect. 2. The author then describes the mode of obtaining a red colouring-matter from ox-gallstones. These concretions have to be extracted with water, alcohol, ether, dilute hydrochloric acid, and ultimately, after repeated extraction with boiling alcohol and ether, with chloroform. This agent dissolves
bilirubine or cholophæine
, and deposits it, on concentration and the addition of absolute alcohol, in an amorphous condition, or in a crystallized state. Sect. 3. The crystals are dark brown, and have a splendid blue lustre. They are rhombic plates, as represented by a drawing in outline taken from a specimen magnified about twenty times. The amorphous or only crystalline modification is a powder of a splendid red, nearly orange-colour. Sect. 4. The elementary analysis of several specimens yielded results which led to the formula C
9
H
9
N O
2
. Sect. o. Bilirubine dissolves in ammonia, but does not form any permanent compound with it. Its combinations with fixed caustic alkalies are insoluble in an excess of lye. The neutral alkali solution, mostly the one in ammonia, yields neutral salts with monodynamic metals, half-acid salts with didy-namic ones. The
neutral monohydrated cholophæinate of silver
, C
9
H
10
AgNO
3
, Sect . Ag = 37·5 per cent., is a reddish-brown precipitate, which does not lose the atom of water at 110° C. As a hydrated silver-salt it is anomalous; but a few other animal products, such as hippuric acid, are known also to form such hydrated silver-salts. By means of this compound, the formula of bilirubine, or cholophæine, above given, is shown to express its atomic weight.
On the variations of the daily range of atmospheric temperature as recorded at the Kew Observatory
Authors: Stewart Balfour
Published: December 2006

1. There are reasons for supposing that differences of temperature in the various portions of our globe and of its atmosphere are, in whatever manner these may be produced, the chief primary causes of meteorological activity. Such differences of temperature produce differences of atmospheric pressure, and these in their turn produce winds. For this reason the daily range of atmospheric temperature has been chosen as an element which serves well, in many respects at least, to indicate the varying meteorological activity of the place, and also because, if it be found capable of indicating useful results, it has the advantage of being observed with little labour, while the observations are compara­tively easy of reduction.
The determination of organic matter in air
Authors: Carnelley Thomas , Mackie William , Roscoe Henry Enfield
Published: December 2006

The Only methods hitherto proposed for determining the amount of organic matter in air are the two devised by the late Dr. Angus Smith (“Air and Rain”). According to the first of these methods, a defi­nite quantity of the air to be examined is slowly bubbled through a dilute solution of potassium permanganate of known strength until it is fully or considerably bleached,' and in the latter ease the amount of undecomposed permanganate determined by oxalic acid. In the second method a known volume of air is bubbled through distilled water, and the latter examined for free and albuminoid ammonia by Wanklyn and Chapman’s process for water analysis. These methods are open to one or more of the following objec­tions :— 1. The time required for a single determination is
very considerable
, and recessarily varies with the amount of organic matter present.
On the effects of joining the cervical sympathetic nerve with the chorda tympani.
Authors: Langley John Newport , Anderson Hugh Kerr
Published: December 2006

It is well known that the cervical sympathetic nerve and the chorda tympani have opposite actions upon the blood-vessels of the sub-maxillary gland, the former causing contraction of the vessels, and the latter, dilatation. Evidence has been given by one of us that the chorda tympani if united with the cervical sympathetic, can in time make connection with the nerve cells of the superior cervical ganglion and become in part vaso-constrictor fibres. Our experiments have been directed to determine whether the cervical sympathetic if allowed an opportunity of becoming connected with the peripheral nerve cells in the course of the chorda tympani will in part change their function from vaso-constrictor to vaso-dilator. Two experiments were made on anæsthetised cats, both give similar results, but one was much more conclusive on the point at issue than the other, and here we shall speak of that only. The superior cervical ganglion was excised and the central end of the cervical sympathetic nerve was joined to the peripheral end of the lingual, which contains the chorda tympani fibres. After allowing time for union and regeneration of the nerves, the cervical sympathetic was stimulated; it caused prompt flushing of the sub-maxillary glands, and the effect was repeatedly obtained.
On the high temperature standards of the national physical laboratory: an account of a comparison of platinum thermometers and thermo-junctions with the gas thermo­meter.
Authors: Harker John Allen , Glazebrook Richard Tetley
Published: December 2006

This paper contains an account of a continuation of the work of Dr. P. Chappuis and the author,* on a comparison of the scale of the gas thermometer with that of certain specially-constructed platinum thermometers, from temperatures below zero up to the boiling point of sulphur, and in one case to a point close to 600° C.
A radial area-scale.
Authors: Edwards R. W. K. , Greenhill Alfred George
Published: December 2006

This is a contrivance for finding the area of a plane figure by mean of a transparency. The design in the transparency consists of number of radiating lines.
On the changes of thermoelectric power produced by magneti­sation, and their relation to magnetic strains.
Authors: Bidwell Shelford
Published: December 2006

It is well known that magnetisation generally produces a change both in the thermoelectric quality of a magnetisable metal, and also in its linear dimensions. In an article published in October, 1902, I directed attention to the remarkable qualitative correspondence which appeared in several cases to exist between the two classes of phenomena, and the experiments which form the subject of the present paper were undertaken with the view of investigating their apparent relation.
On the liquefied hydrides of phosphorus, sulphur, and the halogens, as conducting solvents.—Part I.
Authors: McIntosh D. , Steele Bertram Dillon , Ramsay William
Published: December 2006

Ammonia, water, and hydrofluoric acid, are the only hydrides of the elements which have been systematically investigated with respect to their solvent properties, and in particular with respect to their power of forming electrically conducting solutions. With the object of extending our knowledge of the properties of these hydrogen compounds, when liquefied, and in the hope that more light might thereby be thrown on the question of ionic dissociation, the investiga­tion, of which this is a brief abstract, has been undertaken.
The spectrum of the radium emanation.
Authors: Ramsay William , Collie John Norman
Published: December 2006

Attempts have been made since July, 1903, to see and map the spectrum of the emanation from radium, for at that date the conversion of the emanation into helium was observed by Ramsay and Soddy, and during the first discharge of the induction current through the emanation, it was believed that a peculiar spectrum was noticed; indeed, three lines were persistent, and were mentioned in the communication on the subject in these ‘Proceedings.’ But such attempts have uniformly failed; at the first moment of the discharge, indeed, a brilliant spectrum has twice been observed, which soon became confused and indistinct. It faded before it was possible to map it, and owing to the presence of impurities, generally carbon monoxide, nitrogen, or hydrogen, the special spectrum was obscured. All that could be said was that it appeared to present some brilliantly green lines.
Shape from symmetry: detecting and exploiting symmetry in affine images
Authors: Mukherjee Dipti Prasad , Zisserman Andrew Peter , Brady Michael
Published: December 2006

We investigate the constraints placed on the image projection of a planar object having local reflectional symmetry. Under the affine approximation to projection, we demonstrate an efficient (low-complexity) algorithm for detecting and verifying symmetries despite the distorting effects of image skewing. The symmetries are utilized for three distinct tasks: first, determining image back-projection up to a similarity transformation ambiguity; second, determining the object plane orientation (slant and tilt); and third, as a test for non-coplanarity amongst a collection of objects. These results are illustrated throughout with examples from images of real scenes.