- Kelvin Flexible Metallic Ligament.
Kelvin, Maclean and Galt regard this property of falling water as an objection to the use of a water-dropper indoors, though not of practical importance when it is used out of doors.
Kelvin had previously proposed to define an absolute scale of temperature independent of the properties of any particular substance in terms of Carnot's function by making F'(t) constant.
During the same period a brilliant group of mathematical physicists, notably Lord Kelvin (W.
An instrument of the latter type of considerable accuracy was designed by Lord Kelvin for the British Board of Trade Electrical Laboratory, and it is there used as the principal standard ampere balance.
This contains but a fragment of his scientific discoveries, but it is sufficient to put him in the very foremost rank, though its full value was not recognized until pointed out by Lord Kelvin in 1848 and 1849.
- Lord Kelvin (Sir W.
- Connexions of Kelvin Ampere Balance.
1 See Lord Kelvin, " Report on Electrometers and Electrostatic Measurements," Brit.
The great novelty in the ampere balances of Lord Kelvin was a joint or electric coupling, which is at once exceedingly flexible and yet capable of being constructed to carry with safety any desired current.
Kelvin ampere balances are made in two types - (i) a variable weight type suitable for obtaining the ampere value of any current within their range; and (2) a fixed weight type intended to indicate when a current which can be varied at pleasure has a certain fixed value.
In the use of ammeters in which the control is the gravity of a weight, such as the Kelvin ampere balances and other instruments, it should be noted that the scale reading or indication of the instrument will vary with the latitude and with the height of the instrument above the mean sea-level.
- For switchboard use i n Ammeter Kelvin & electric supply stations where space is valuable, James White instruments of the type called edgewise ammeters Ltd.
Thomson (afterwards Lord Kelvin) in 1847, as the result of a mathematical investigation undertaken to explain Faraday's experimental observations.
The influence of traction in diminishing the susceptibility of nickel was first noticed by Kelvin (W.
Thomson (Lord Kelvin), who in 1856 announced that magnetization rendered iron and steel positive to the unmagnetized metals.'
Thomson (afterwards Lord Kelvin) in 1849 that while no physical evidence could be adduced in support of the hypothesis, certain discoveries, especially in electromagnetism, rendered it extremely improbable (Reprint, p. 344).
Thomson (Lord Kelvin), Reprint of Papers on Electrostatics and Magnetism (London, 1884, containing papers on magnetic theory originally published between 1844 and 1855, with additions); J.
An experiment was devised by Lord Kelvin for demonstrating this, in which the difference of steadiness was shown of a copper shell filled with liquid and spun gyroscopically, according as the shell was slightly oblate or prolate.
The reader is also referred to an article by Lord Kelvin (Reprint of Papers on Electrostatics and Magnetism, p. 178), entitled " Determination of the Distribution of Electricity on a Circular Segment of a Plane, or Spherical Conducting Surface under any given Influence," where another equivalent expression is given for the capacity of an ellipsoid.
Another comparison method much used in submarine cable work is the method of mixtures, originally due to Lord Kelvin and usually called Thomson and Gott's method.
A very powerful method of attacking problems in electrical distribution was first made known by Lord Kelvin in 1845 and is described as the method of electrical images.'
In the collected Scientific Papers of Lord Kelvin (3 vols., Cambridge, 1882), of James Clerk Maxwell (2 vols., Cambridge, 1890), and of Lord Rayleigh (4 vols., Cambridge, 1903), the advanced student will find the means for studying the historical development of electrical knowledge as it has been evolved from the minds of some of the master workers of the 19th century.
Thomson (Lord Kelvin) from Regnault's tables of the properties of steam, assuming the gaseous laws, did not vary exactly as J/T.
This most fundamental point was finally settled by a more delicate test, devised by Lord Kelvin, and carried out in conjunction with Joule (1854), which showed that the fundamental assumption W =H in isothermal expansion was very nearly true for permanent gases, and that F'(t) must therefore vary very nearly as J/T.
- William Thomson (Lord Kelvin), who wars the first to realize the importance of the absolute scale in thermodynamics, and the inadequacy of the test afforded by Boyle's law or by experiments on the constancy of the specific heat of gases, devised a more delicate and practical test, which he carried out successfully in conjunction with Joule.
- Slider of Kelvin Ampere Balance.
His results, according to Kelvin, led directly and speedily to the present practical method of surface-condensation, one of the most important improvements of the steam engine, especially for marine use, since the days of James Watt.
Thomson (Lord Kelvin) and P. G.
This description, quoted from James Clerk Maxwell's article in the 9th edition of the Encyclopaedia Britannica, represents the historical position of the subject up till about 1860, when Maxwell began those constructive speculations in electrical theory, based on the influence of the physical views of Faraday and Lord Kelvin, which have in their subsequent development largely transformed theoretical physics into the science of the aether.
In 1859 he began, in concert with Sir William Thomson (afterwards Lord Kelvin), to work on problems respecting the making and use of cables, and the importance of his researches on the resistance of gutta-percha was at once recognized.
This leads up to the fundamental distinction, introduced by Lord Kelvin, between "available energy," which we can turn to mechanical effect, and "diffuse energy," which is useless for that purpose.
It was pointed out by Thomson (Lord Kelvin) and P. G.
This general law, known as the principle of the "dissipation of energy," was first adequately pointed out by Lord Kelvin in 1852; and was applied by him to some of the principal problems of cosmical physics.
Thomson (Lord Kelvin) at a meeting of the Philosophical Society of Glasgow in 1854, because its greater flexibility renders it less likely to damage the insulating envelope during the manipulation of the cable.
What may be called a mechanical Kelvin in a patent taken out by him in 1858.
31), for which Lord Siphon Kelvin obtained his first recorder.
The automatic curb sender was originally designed by Lord Kelvin for the purpose of diminishing the effect of inductive re- Au tardation in long cables.
Thomson (Lord Kelvin) observed in 1863 3 that when a condenser is charged or discharged, a sharp click is heard, and a similar observation was made by Cromwell F.
Lord Kelvin (Sir W.
With Lord Kelvin he collaborated in writing the well-known Treatise on Natural Philosophy.
Very convenient and accurate instruments based on the above principles have been devised by Lord Kelvin, and a large variety of these ampere balances, as they are called, suitable for measuring currents from a fraction of an ampere up to many thousands of amperes, have been constructed by that illustrious inventor.
The earliest formulation of the subject, due to Lord Kelvin, assumed that this relation was true in all cases, and, calculated in this way, the electromotive force of Daniell's cell, which happens to possess a very small temperature coefficient, was found to agree with observation.
Villari in 1868 that the magnetic susceptibility of an iron wire was increased by stretching when the magnetization was below a certain value, but diminished when that value was exceeded; this phenomenon has been termed by Lord Kelvin, who discovered it independently, the " Villari reversal," the value of the magnetization for which stretching by a given load produces no effect being known as the " Villari critical point " for that load.
The experiment was the reverse of one made by Kelvin with a gunbarrel subjected to internal hydrostatic pressure (Phil.
Thomson (Lord Kelvin) to form a theory of vortex atoms in a homogeneous, incompressible and frictionless liquid."
If we suppose that the aether differs from ordinary matter in degree but not in kind, we can obtain some idea of its quality from a knowledge of the velocity of radiation and of its possible intensity near the sun, in a manner applied long ago by Lord Kelvin (Trans.
Lord Kelvin assumed as a superior limit of k, the ratio of amplitude to wave-length, the value io 2, which is a very safe limit.
A train of ideas which strongly impressed itself on Clerk Maxwell's mind, in the early stages of his theoretical views, was put forward by Lord Kelvin in 1858; he showed that the special characteristics of the rotation of the plane of polarization, discovered by Faraday in light propagated along a magnetic field, viz.
Lord Kelvin was thereby induced to identify magnetic force with rotation, involving, therefore, angular momentum in the aether.
Long previously Lord Kelvin himself came nearer this view, in offering the opinion that magnetism consisted, in some way, in the angular momentum of the material molecules, of which the energy of irregular translations constitutes.
On such a view the aether might conceivably be a perfect fluid, its fundamental property of elastic reaction arising (as at one time suggested by Kelvin and G.
Strutt, made him known over Europe; and his powers rapidly matured until, at the death of Clerk Maxwell, he stood at the head of British physicists, Sir George Stokes and Lord Kelvin alone excepted.
The preface contributed to the first of these by Lord Kelvin, and the introductions to the second and third by Professors P. E.
Of flame collectors the two best known are Lord Kelvin's portable electrometer with a fuse, or F.
Of liquid collectors the representative is Lord Kelvin's water-dropping electrograph; while Benndorf's is the form of radium collector that has been most used.
It should be added that the modern theory of vortex-atoms (Lord Kelvin's) to explain the constitution of matter has but slight analogy with Cartesian doctrine, and finds a parellel, if anywhere, in a modification of that doctrine by Malebranche.
- Lord Kelvin's early Siphon Recorder.
" Thomson and Tait," as it is familiarly called ("T and T" was the authors' own formula), was planned soon after Lord Kelvin became acquainted with Tait, on the latter's appointment to his professorship in Edinburgh, and it was intended to be an all-comprehensive treatise on physical science, the foundations being laid in kinematics and dynamics, and the structure completed with the properties of matter, heat, light, electricity and magnetism.
- Lord Kelvin's Ampere Balance.
Assoc. Report for 1867, or Lord Kelvin's Reprint of Papers on Electrostatics and Magnetism, p. 260.
In practice we can avoid the difficulty due to irregular distribution of electric force at the edges of the plate by the use of a guard plate as first suggested by Lord Kelvin.
(26), that distribution, together with the point-charge +q at A, will make a distribution of electric force at all points outside the sphere 2 See Lord Kelvin's Papers on Electrostatics and Magnetism, p. 144.
Lord Kelvin's experiment with a current of gas forced through a porous plug is also given.
(If the molecules of air at normal temperature and pressure were arranged in cubical order, the edge of each cube would be about 2.9 X I o - ' cms.; the average diameter of a molecule in air is 2.8X Io - 8 cms.) Further and very important evidence as to the nature of the gaseous state of matter is provided by the experiments of Joule and Kelvin.
Rankine, was therefore much vivified by Lord Kelvin's specification (Comptes Rendus, 1889) of a material gyrostatically constituted medium which would possess this character.
In the course of the controversy three presidents of the Royal Society, Lord Kelvin, Lord Lister and Sir W.
Lamb, C. Chree, Lord Rayleigh); and to hydrodynamics (Lord Kelvin, Sir G.
Fleming, Lord Kelvin and W.
One of the best known of these is Lord Kelvin's multicellular voltmeter.
- Lord Kelvin's Multicellular Electrostatic Voltmeter.
Instruments of this kind have been constructed not only by Lord Kelvin, but also by W.
- Round Dial Kelvin Multicellular Electrostatic Voltmeter, 5-in.
- Thomson's (Lord Kelvin's) (Frame and Needles).
Several kinds of deflector have been invented, that of Lord Kelvin (Sir William Thomson) being the simplest, but Dr Waghorn's is also very effective.
He introduced a pattern having four or five parallel straight strips of magnetized steel fixed under a card, a form which remained the standard admiralty type until the introduction of the modern Thomson (Kelvin) compass in 1876.
The names of the first recipients were: Earl Roberts, Viscount Wolseley, Viscount Kitchener, Sir Henry Keppel, Sir Edward Seymour, Lord Lister, Lord Rayleigh, Lord Kelvin, John Morley, W.
Lord Kelvin also devised an influence machine, commonly called a" mouse mill,"for electrifying the ink in connexion with his siphon recorder.
- Lord Kelvin's Replenisher.
Bouchotte have 1 See Lord Kelvin, Reprint of Papers on Electrostatics and Magnetism (1872);" Electrophoric Apparatus and Illustrations of Voltaic Theory,"p. 319;" On Electric Machines Founded on Induction and Convection,"p. 330;" The Reciprocal Electrophorus,"P. 337.
- Round Dial Voltmeter of Kelvin Siphon Recorder, dead beat moving coil type, with front removed.
Preston, Theory of Heat, cap. vii.; Kelvin, Collected Papers; O.
In the use of all these electroscopic instruments it is essential to bear in mind (as first pointed out by Lord Kelvin) that what a gold-leaf electroscope really indicates is the difference of potential between the gold-leaf and the solid walls enclosing the air space in which they move.'
This argument is due to Lord Kelvin and P. G.
The accuracy of his measurement, by which he established within 2% the above law, was only limited by the sensibility, or rather insensibility, of the pith ball electrometer, which was his only means of detecting the electric charge.2 In the accuracy of his quantitative measurements and the range of his researches and his combination of mathematical and physical knowledge, Cavendish may not inaptly be described as the Kelvin of the 18th century.
He ascertained the distribution of electricity among several spheres (whether equal or unequal) placed in contact in a straight line; and he measured the distribution of 2 In 1878 Clerk Maxwell repeated Cavendish's experiments with improved apparatus and the employment of a Kelvin quadrant electrometer as a means of detecting the absence of charge on the inner conductor after it had been connected to the outer case, and was thus able to show that if the law of electric attraction varies inversely as the nth power of the distance, then the exponent n must have a value of 2 t Isua.
In 1851 Lord Kelvin (Sir W.
Lord Kelvin's Work.
- About 1842 Lord Kelvin (then William Thomson) began that long career of theoretical and practical discovery and invention in electrical science which revolutionized every department of pure and applied electricity.
Scientific and practical questions connected with the possibility of laying an Atlantic submarine cable then began to be discussed, and Lord Kelvin was foremost in developing true scientific knowledge on this subject, and in the invention of appliances for utilizing it.
Lord Kelvin's mirror galvanometer was first used in receiving signals through the short-lived 1858 cable.
Lord Kelvin's contributions to the science of exact electric measurement 2 were enormous.
In this work Lord Kelvin took a leading part.
The accumulating determinations of the numerical value of the electromagnetic velocity (v) from the earliest made by Lord Kelvin (Sir W.
Lord Kelvin showed that Faraday's discovery demonstrated that some form of rotation was taking place along lines of magnetic force when passing through a medium.'
The theory of electro-optics received great attention from Kelvin, Maxwell, Rayleigh, G.
Burbury, The Mathematical Theory of Electricity and Magnetism (2 vols., 1885); Lord Kelvin (Sir William Thomson), Mathematical and Physical Papers (3 vols., Cambridge, 1882); Lord Rayleigh, Scientific Papers (q.
Thomson (Lord Kelvin), he may be regarded as one of the founders of the now universally received law of the conservation of energy.
The most important improvements in connexion with electrometers are due, however, to Lord Kelvin, who introduced the guard plate and used gravity or the torsion of a wire as a means for evaluating the electrical forces.
2 - Kelvin's Portable Electrometer.
Symmetrical Electrometers include the dry pile electrometer and Kelvin's quadrant electrometer.
A vast improvement in this instrument was made by the invention of the quadrant electrometer by Lord Kelvin, which is the most sensitive form of electrometer yet devised.
- Kelvin's Absolute Electrometer.
- Kelvin's Quadrant Electrometer.
Lord Kelvin provided the instrument with two necessary adjuncts, viz.
Thomson (afterwards Lord Kelvin) investigated the effect of the curvature of the surface of a liquid on the thermal equilibrium between the liquid and the vapour in contact with it.
From this consideration we may derive Laplace's expression, as has been done by Dupre (Theorie mecanique de la chaleur, Paris, 1869), and Kelvin (" Capillary Attraction," Proc. Roy.
Conversely, if two fluids mix, it would seem that T'12 must exceed the mean of T 1 and T2; otherwise work would have to be expended to effect a close alternate stratification of the two bodies, such as we may suppose to constitute a first step in the process of mixture (Dupre, Theorie mecanique de la chaleur, p. 372; Kelvin, Popular Lectures, p. 53).
Lord Kelvin proposed to distinguish the latter kind of waves by the name of ripples.
[Lord Kelvin's formula (I) may be applied to find the surf acetension of a clean or contaminated liquid from observations upon the length of waves of known periodic time, travelling over the surface.
A calculation analogous to that of Lord Kelvin may be applied to find the frequency of small transverse vibrations of a cylinder of liquid under the action of the capillary force.
Lord Kelvin has applied the principles of Thermodynamics to determine the thermal effects of increasing or diminishing the area of the free surface of a liquid, and has shown that in order to keep the temperature constant while the area of the surface increases by unity, an amount of heat must be supplied 275 to the liquid which is dynamically equivalent to the product of the absolute temperature into the decrement of the surface-tension per degree of temperature.
It had the right to levy customs and dues on all vessels on the Clyde between Loch Long and the Kelvin.
He also published biographies of Reis, Faraday and Kelvin.
Towards the end of the 10th century Lord Kelvin (then Sir W.
For the measurement of low resistances a modification of the Wheatstone's bridge devised by Lord Kelvin is employed.
The Kelvin bridge consists of nine conductors joining six points, and in one practical form is known as a Kelvin and Varley slide.
This result was verified by his brother, Sir William Thomson (Lord Kelvin), in 1850.
- Thomson (Lord Kelvin) had already pointed out (Proc. R.S.
Thus this small flexibility is even greater than that necessary to the reconciliation of observation with theory, and the earth is shown to be more rigid than steel - a conclusion long since announced by Kelvin for other reasons.
WILLIAM THOMSON KELVIN, Baron (1824-1907), British physicist, the second son of James Thomson, I.L.D., professor of mathematics in the university of Glasgow, was born at Belfast, Ireland, on the 26th of June 1824, his father being then teacher of mathematics in the Royal Academical Institution.
Although his contributions to thermodynamics may properly be regarded as his most important scientific work, it is in the field of electricity, especially in its application to submarine telegraphy, that Lord Kelvin is best known to the world at large.
Some account of Thomson's electrometer is given in the article on that subject, while every modern work of importance on electric lighting describes the instruments which he has specially designed for central station work; and it may be said that there is no quantity which the electrical engineer is ordinarily called upon to measure for which Lord Kelvin did not construct the suitable instrument.
It is impossible within brief limits to convey more than a general idea of the work of a philosopher who published more than three hundred original papers bearing upon nearly every branch of physical science; who one day was working out the mathematics of a vortex theory of matter on hydrodynamical principles or discovering the limitations of the capabilities of the vortex atom, on another was applying the theory of elasticity to tides in the solid earth, or was calculating the size of water molecules, and later was designing an electricity meter, a dynamo or a domestic water-tap. It is only by reference to his published papers that any approximate conception can be formed of his life's work; but the student who had read all these knew comparatively little of Lord Kelvin if he had not talked with him face to face.
Extreme modesty, almost amounting to diffidence, was combined with the utmost kindliness in Lord Kelvin's bearing to the most elementary student, and nothing seemed to give him so much pleasure as an opportunity to acknowledge the efforts of the humblest scientific worker.
Cormack, wrote of him: "It is perhaps at the lecture table that Lord Kelvin displays most of his characteristics..
In 1866, perhaps chiefly in acknowledgment of his services to transAtlantic telegraphy, Thomson received the honour of knighthood, and in 1892 he was raised to the peerage with the title of Baron Kelvin of Largs.
About 2500 guests were received in the university buildings, the library of which was devoted to an exhibition of the instruments invented by Lord Kelvin, together with his certificates, diplomas and medals.
The Eastern, the Anglo-American and the Commercial Cable companies united to celebrate the event, and from the university library a message was sent through Newfoundland, New York, Chicago, San Francisco, Los Angeles, New Orleans, Florida and Washington, and was received by Lord Kelvin seven and a half minutes after it had been despatched, having travelled about 20,000 miles and twice crossed the Atlantic during the interval.
It was at the banquet in connexion with the jubilee celebration that the Lord Provost of Glasgow thus summarized Lord Kelvin's character: "His industry is unwearied; and he seems to take rest by turning from one difficulty to another - difficulties that would appal most men and be taken as enjoyment by no one else..
This life of unwearied industry, of universal honour, has left Lord Kelvin with a lovable nature that charms all with whom he comes in contact."
Three years after this celebration Lord Kelvin resigned his chair at Glasgow, though by formally matriculating as a student he maintained his connexion with the university, of which in 1904 he was elected chancellor.
See Andrew Gray, Lord Kelvin (1908); S.
P. Thompson, Life of Lord Kelvin (1910), which contains a full bibliography of his writings.
Lord Kelvin in The Age of the Earth, 1897, p. 7).
The Millenium lamps which now adorn all the Kelvin Bridges, look very nice.
The 17th British colloquium for Theoretical Computer Science was held in early April 2001 in the Kelvin Conference Center in Glasgow.
common logarithm of color temperature in Kelvin for each diluted Planck component.
fly fishing is really quite easy; to fish a river like the Kelvin you will need a suitable rod.
Kelvin john carruthers.
Kelvin beattie and when he thought.
Kelvin wave: a long wave in the oceans whose characteristics are altered by the rotation of the earth.
Very serious indeed to i'll be the program from as lord Kelvin.
In SI units the specific heat capacity is the amount of heat required to raise 1 kg mass through 1 degree Kelvin.
Within a matter of minutes rovers took the lead with Bellamy pouncing on a handling error by Kelvin Davis.
As Lord Kelvin has shown (Baltimore Lectures, p. 304, 1904) (16) may also be obtained by the consideration of the mean density of the altered medium.
Sella, reference may be made to Lord Kelvin's Baltimore Lectures, p. 317, where a higher estimate of the value of n is favoured.
The invention of the portable electrometer and the water-dropping electrograph by Lord Kelvin in the middle of the 19th century, and the greater definiteness thus introduced into observational results, were notable events.
Kelvin, Maclean and Galt (34) found the effect greatest in the air near the level of impact.
The subsequent researches of Dr Joule and Lord Kelvin (Phil.
Clausius and Lord Kelvin on the basis of "Carnot's principle" (1824), modified in expression so as to be consistent with the conservation of energy (see Energetics).
Thomson (Lord Kelvin) Mathematical and Physical Papers, vol.
For nearly a week futile attempts were made to send messages by his methods, and then a return was made to the weak currents and the mirror galvanometers of Sir William Thomson (Lord Kelvin) which had been employed for testing purposes while the cable was being laid.
Between 1886 and 1892 he published a series of papers on the foundations of the kinetic theory of gases, the fourth of which contained what was, according to Lord Kelvin, the first proof ever given of the Waterstdn-Maxwell theorem of the average equal partition of energy in a mixture of two different gases; and about the same time he carried out investigations into impact and its duration.
The mathematical theory which was constructed by Poisson, and extended and freed from doubtful hypotheses by Kelvin, has been elaborated by other investigators, notably F.
The torque T at any instant of steady running is therefore I WR Lord Kelvin patented a brake in 1858 (fig.
Wilson, "The Kelvin Quadrant Electrometer as a Wattmeter," Proc. Roy.
One much-used electrostatic voltmeter of this type is the Kelvin multicellular vertical pattern voltmeter (fig.
The action of Lord Kelvin's replenisher (fig.
Lord Kelvin has classified electrometers into (I) Repulsion, (2) Attracted disk, and (3) Symmetrical electrometers (see VV.
Lord Kelvin's absolute electrometer (fig.
The potential difference, due to the Volta effect in air, has been shown by Thomson (Lord Kelvin) and his pupils to be of the same order of magnitude, if not absolutely the same, as that produced in a dilute electrolyte in which two metallically connected plates (e.g.
Within a matter of minutes Rovers took the lead with Bellamy pouncing on a handling error by Kelvin Davis.
Paul J Medford is best known as Kelvin Carpenter, one of the original characters in the BBC1 soap EastEnders.
Other knots include the Pratt, Windsor, Half Windsor, Kelvin, Oriental and St. Andrew, just to name a few.
Lord Kelvin initially entertained the concept of measuring time with atomic vibrations in 1879.
Their first performance as a band was in the West End of Glasgow, in the Kelvin Hall under the name of The Run-Rig Dance Band, in 1973.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.