scholarly journals Investigations in absolute radiometry

1937 ◽  
Vol 161 (904) ◽  
pp. 1-38 ◽  
Keyword(s):  
Radiation Intensity ◽  
National Physical Laboratory ◽  
Independent Evidence ◽  
Late Professor ◽  
Physical Laboratory ◽  
The Subject ◽  
Improved Design ◽  
Single Instrument ◽  
New Instruments ◽  
Made In

Of modern British work seeking to establish a scale of radiation intensity the most important is that of the late Professor H. L. Callendar (1910), who developed a very accurate instrument, the Callendar Radio-balance, for measuring radiation. Subsequently Callendar used the radio-balance to calibrate various types of radiometer produced by British instrument makers. After his death, arrangements were made for this work to be continued at the National Physical Laboratory. The instrument used to establish a scale of radiation intensity at this Laboratory was a radio-balance made to an improved design of Callendar’s shortly before his death. It was made in the Physics workshops of the Imperial College of Science and calibrated at the National Physical Laboratory as described in the second of these papers. Other scales, notably those known as the Smithsonian Scale of 1913 and the Ångström Scale, have also been employed in this and other countries, particularly for the calibration of meteorological instruments; and it has been recognized for some time that these scales are not in agreement. The discrepancies indicated the importance of obtaining independent evidence of the accuracy of the N. P. L. scale rather than continuing to rely on the properties of a single instrument. Accordingly, the first steps taken in a long investigation, which ultimately led to complete justification of the faith reposed in the radio-balance, concerned the development of absolute radio-meters of an entirely different type. Descriptions of these new instruments, and of the method of using them, form the subject of this first paper.

scholarly journals VIII. Gaseous combustion at medium pressures. Part I. —Carbon monoxide air explosions in a closed vessel. Part II. —Methane-air explosions in a closed vessel

1926 ◽  
Vol 225 (626-635) ◽  
pp. 331-356 ◽  
Keyword(s):  
Carbon Monoxide ◽  
National Physical Laboratory ◽  
Closed Vessel ◽  
Engineering Research ◽  
The Past ◽  
Physical Laboratory ◽  
Wide Range ◽  
The Subject ◽  
Temperature And Pressure ◽  
Air Explosion

During the past five years a programme of research involving air-fuel explosions in a closed vessel has been in progress at the National Physical Laboratory for the Engineering Research Board of the Department of Scientific and Industrial Research. Among the experimental results obtained, those relating to Carbon Monoxide and Methane were considered likely to be of interest to the Society, and form the subject of the present communication. Of the two investigations described, the first gives experimental data on the respective influences of hydrogen-air and water vapour on a carbon monoxide-air explosion, and the second relates to explosions of methane and air over a comparatively wide range of initial temperature and pressure.

scholarly journals John Edward Lennard-Jones, 1894-1954

1955 ◽  
Vol 1 ◽  
pp. 174-184 ◽  
Keyword(s):  
Royal Society ◽  
Trinity College ◽  
National Physical Laboratory ◽  
Grammar School ◽  
Atoms And Molecules ◽  
Lennard Jones ◽  
Physical Laboratory ◽  
The Subject ◽  
The University ◽  
University Of Manchester

John Lennard-Jones was born on 27 October 1894 in Leigh, Lancashire and was educated at Leigh Grammar School, where he specialized in classics. In 1912 he entered Manchester University, changed his subject to mathematics in which he took an honours degree and then an M.Sc. under Professor Lamb, carrying out some research on the theory of sound. In 1915 he joined the Royal Flying Corps, obtained his Wings in 1917 and saw service in France; he also took part in some investigations on aerodynamics with Messrs Boulton and Paul and at the National Physical Laboratory. In 1919 he returned to the University of Manchester as lecturer in mathematics, took the degree of D.Sc. of that university and continued to work on vibrations in gases, becoming more and more interested in the gas-kinetic aspects of the subject as his paper of 1922 in the Philosophical Transactions of the Royal Society shows. In 1922, on the advice of Professor Sydney Chapman, he applied for and was elected to a Senior 1851 Exhibition to enable him to work in Cambridge, where he became a research student at Trinity College and was awarded the degree of Ph.D. in 1924. At Cambridge under the influence of R. H. Fowler he became more and more interested in the forces between atoms and molecules and in the possibility of deducing them from the behaviour of gases.

scholarly journals XX.—On the Thermal Conductivity and Specific Heat of Manganese-Steel

1890 ◽  
Vol 35 (4) ◽  
pp. 947-954 ◽  
Author(s):  
A. Crichton Mitchell
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Tensile Strength ◽  
Specific Heat ◽  
Manganese Steel ◽  
Physical Laboratory ◽  
The Subject ◽  
General Opinion ◽  
Made In

Until a few years ago it was the general opinion among metallurgists that the presence of manganese in steel exceeding the proportion of 1 per cent, is prejudicial to the value of the steel, inasmuch as a higher percentage of manganese has the effect of lowering markedly its tensile strength and toughness. But in 1884, Messrs Hadfield & Company, of the Hecla Steel Works, Sheffield, exhibited, at a meeting of the Institute of Mechanical Engineers, a number of samples of steel containing upwards of 10 to 15 per cent, of manganese, and submitted the results of experiments, which showed that the samples were, in point of tensile strength and hardness, in no way inferior to steel. Again, in 1888, Mr R. A. Hadfield read to the Institute a paper on the subject, giving the details of a large number of tests, which brought to light some interesting mechanical properties of alloys of manganese and iron. Since its introduction, these alloys (and particularly that containing 10 to 15 per cent, of manganese, known as “manganese-steel”) have been studied by several physicists, and further peculiarities have been found. It appeared desirable that the thermal conductivity of so peculiar a substance should be investigated. The present paper is an account of experiments made in the Physical Laboratory, Edinburgh University, with a view to the determination of its thermal conductivity. In the reduction of such experiments a knowledge of the specific heat is necessary, hence there is also given an account of experiments whereby the specific heat was determined.

scholarly journals An account of the pendulum observations connecting kew and greenwich observatories made in 1903

1906 ◽  
Vol 78 (524) ◽  
pp. 241-247
Keyword(s):  
National Physical Laboratory ◽  
Base Station ◽  
Central Bureau ◽  
Geodetic Institute ◽  
Secretary Of State ◽  
Physical Laboratory ◽  
The Government ◽  
Made In

1. The observations, of which a brief account is here given, had their origin in the decision of the Government of India to resume the pendulum work which was brought to a close in 1870. Professor F. R. Helmert, Director of the Central Bureau of the International Geodetic Association, to whose advice the India Office is much indebted, recommended the use of a half-seconds pendulum equipment as designed by Colonel von Sterneck. This equipment was ordered through the Geodetic Institute at Potsdam, and the constants for the necessary pressure and temperature corrections were determined there by Professor L. Haasemann, under Professor Helmert’s direction. A redetermination of these constants was made at Kew, at Professor Helmert’s suggestion, and results were obtained in very close accordance with those found at Potsdam. The apparatus gives only relative determinations of gravity; it was thus necessary to select a base station. As Kew Observatory had been the base station of the older Indian pendulum observations it was again selected, Dr. Glazebrook, Director of the National Physical Laboratory, having given permission and promised all necessary assistance. Meantime, a suggestion was made by the Astronomer Royal, and accepted by the Secretary of State for India, that the opportunity should be taken of swinging the pendulums also at Greenwich, thus allowing of a fresh intercomparison of g at Greenwich and Kew.

scholarly journals Thomas Lydwell Eckersley, 1886-1959

1960 ◽  
Vol 5 ◽  
pp. 69-74
Keyword(s):  
Transmission Lines ◽  
Good Deal ◽  
National Physical Laboratory ◽  
Radio Waves ◽  
Thomas Henry Huxley ◽  
Physical Laboratory ◽  
University College London ◽  
The Subject ◽  
The University ◽  
Alternating Magnetic Fields

Thomas Lydwell Eckersley was born on 27 December 1886 in London. His mother was a daughter of Thomas Henry Huxley who was at one time President of the Royal Society. From the age of 2 1/2 to 6 Eckersley lived in Mexico where his father, who was a civil engineer, was engaged in building a railway. In his early life Eckersley was interested in engineering and in scientific devices and he had a desire to emulate his father and to build bridges. At the age of 11 he went to Bedales School where he came under the influence of an able teacher of mathematics who laid the foundations of his life-long interest in the subject. He left school at the early age of 15 and went to University College London, to read engineering, but he found he was not really as interested in the practical aspects of the work as he had at one time supposed, and he achieved only a Second Class degree. On leaving the University he went to the National Physical Laboratory where he found himself working under Albert Campbell on the behaviour of iron under the influence of alternating magnetic fields. Through this work he became interested in magnetic detectors for radio waves, and he did a good deal of experimenting with radio apparatus at his own house. His first paper was published, jointly with Campbell, on the effect of Pupin loading coils on waves travelling along transmission lines.

scholarly journals Leonard Bairstow, 1880-1963

1965 ◽  
Vol 11 ◽  
pp. 22-40
Keyword(s):  
Wind Tunnel ◽  
National Physical Laboratory ◽  
Practical Applications ◽  
Aerodynamic Derivatives ◽  
Physical Laboratory ◽  
Engineering Department ◽  
Tunnel Design ◽  
Wide Experience ◽  
Wind Tunnel Design ◽  
Made In

Leonard Bairstow was born at Halifax in Yorkshire on 25 June 1880 and began his education in the elementary and secondary schools of Halifax. In 1898 he obtained a scholarship at the Royal College of Science, London, where he was a fellow student of H . E. Wimperis, who declared in later years: ‘I remember that, for several decades there, the most brilliant student that had been produced by the College was Professor Bairstow. He had an uncanny faculty of making himself acquainted with and making completely original suggestions on subjects which we did not think he knew anything about.' He became a Whitworth Scholar in 1902 and took prizes in mechanics and astrophysics. In 1904 he entered the Engineering Department of the National Physical Laboratory. There he worked under Dr T. E. (later Sir Thomas) Stanton on problem s of fatigue and of aerodynamics. In 1909 he was appointed to the staff of the new section of Aerodynamics (later called the Aerodynamics Division), of which he became the Assistant (or Principal) in charge. During this period he carried out some pioneer investigations into wind-tunnel design, and made important developments and practical applications of the theory of aircraft stability due to G. H. Bryan. This theory he illustrated by the use of small mica models of aircraft, and the necessary measurements of aerodynamic derivatives were made in the wind tunnel. In 1917 he was elected a Fellow of the Royal Society and made a G.B.E. Glazebrook had offered him the post of Superintendent of the Aerodynamics Department at the N.P.L. but Bairstow resigned and was appointed to the Air Board to work for Sir David Henderson on the design of aircraft and on aerodynamics research. There Bairstow worked at the Hotel Cecil as deputy to Alec Ogilvie and, with his wide experience, was able to co-ordinate the departmental work on structural strength, aerodynamics, performance and air screws.

scholarly journals On the effect of the form of the transverse section on the frictional resistance to the motion of an elongated body parallel to its length through a fluid

1915 ◽  
Vol 92 (636) ◽  
pp. 144-157 ◽  
Keyword(s):  
Eddy Currents ◽  
Transverse Section ◽  
Practical Importance ◽  
Frictional Resistance ◽  
National Physical Laboratory ◽  
Cornell University ◽  
Physical Laboratory ◽  
Series Of Experiments ◽  
The Subject

1. The great increase in tire lengths of the parallel mid-bodies of recently constructed submarines and airships has raised into prominence the question of the frictional resistance of such elongated bodies moving parallel to their length through fluids, like air and water, whose viscosities cannot be neglected. This resistance increases as the length increases, and benefits comparable with the head and tail resistances, which for short bodies constitute nearly the whole resistance. In general, the problem of greatest practical importance is the determination of the frictional resistance when the motion is rapid enough to produce eddy currents in the fluid, but the difficulties in the way of a general theory of eddy current motion have presented a solution being reached. The simpler problem of the resistance offered by the walls of a circular pipe to the turbulent flow of viscous fluid through the pipe formed the subject of extensive series of experiments by Saph and Schoder, of Cornell University, and by Stanton and Pannell at the National Physical Laboratory.

scholarly journals Short index to reports of physical observations (electric, magnetic, meteorological, seismological) made at Kew observatory

1912 ◽  
Vol 86 (588) ◽  
pp. 358-359
Keyword(s):  
Observational Data ◽  
Annual Report ◽  
National Physical Laboratory ◽  
Magnetic Storms ◽  
Annual Reports ◽  
Tabular Form ◽  
Short List ◽  
Primary Interest ◽  
Physical Laboratory ◽  
The Subject

A summary of observational data obtained at Kew Observatory used to be given in an Annual Report, which was printed in the Royal Society's 'Proceedings' up to the year 1900. From 1901 to 1909 these data were published in the Annual Report of the National Physical Laboratory, of which Kew Observatory then formed a department. The data for 1910 have been published by the Meteorological Office, which came into occupation of the Observatory on July 1, 1910. As the Reports of the National Physical laboratory are not unlikely to be overlooked by those whose primary interest is in observational work, the Gassiot Committee decided, in October, 1911, that it was desirable that a short list of their observational contents should be published in the Royal Society's 'Proceedings.' The descriptions of the data, which appeared in tabular form in the Annual Reports, are arranged below according to the subject; when there is no specific statement to the contrary, they refer to Kew Observatory. Reference to some of the more outstanding phenomena-especially the magnetic storms–will be found in the text of the Annual Reports.

scholarly journals A discussion on Units and Standards

1946 ◽  
Vol 186 (1005) ◽  
pp. 149-217 ◽  
Keyword(s):  
Short Review ◽  
National Physical Laboratory ◽  
International Committee ◽  
Short History ◽  
Physical Laboratory ◽  
International Authority ◽  
History Of ◽  
The Subject ◽  
Executive Body

The sequence of papers following, contributed by members of the staff of the National Physical Laboratory, gives an account of most of the units and standards which are studied at the Laboratory. Each paper explains briefly the principal technical points involved, together with a short history. Of necessity a standard is to some extent a convention, and it may therefore be well to introduce the subject by a short review of the legal and conventional authorities on which they depend. For the metric system the main international authority is the Conference Generale des oids et Mesures, at which duly accredited delegates of each of the thirty-two nations subscribing to the 1875 Treaty, the Convention du Metre, are present, and which, in normal circumstances, meets every six years. The Comite International des Poids et Mesures is the Executive body appointed by the Conference Generale to manage the affairs of the Bureau International des Poids et Mesures between meetings of the Conference Generale. It consists of eighteen members, elected by the Conference, each of whom must belong to a different State, but who, as members of the Committee, are no longer representatives only of their individual countries, but of all subscribing countries. The International Committee meets every two years, makes recommendations to the General Conference, or acts on authority delegated to it by the Conference.

scholarly journals National Physical Laboratory Radiocarbon Measurements VII

Radiocarbon ◽  
1970 ◽  
Vol 12 (1) ◽  
pp. 181-186 ◽  
Author(s):  
W. J. Callow ◽  
Geraldine I. Hassall
Keyword(s):  
Measurement Technique ◽  
National Physical Laboratory ◽  
Term Stability ◽  
Long Term Stability ◽  
Physical Laboratory ◽  
Made In

The following list comprises measurements made since those reported in Radiocarbon, 1969, v. 11, p. 130–136. No changes have been made in measurement technique or in the method of calculating the results described in Radiocarbon, 1965, v. 7, p. 156–161. It was necessary during 1968 to replace all the geiger counters used in the anti-coincidence rings, but the long term stability of background and standard count rates implicit in the use of a 20-week rolling mean has been maintained.

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