XI. Note on an extension of the comparison of magnetic disturbances with magnetic effects inferred from observed terrestrial galvanic currents; and discussion of the magnetic effects inferred from galvanic currents on days of tranquil magnetism

In a communication to the Royal Society, which was honoured by publication in the Philosophical Transactions for 1868, I described the methods and gave the results of comparing the Magnetic Disturbances which might be expected as consequent on the Terrestrial Galvanic Currents recorded by the self-registering galvanometers of the Royal Observatory of Greenwich, with the Magnetic Disturbances actually registered by the self-registering magnetometers. The comparison was limited to seventeen days (1865, October 5 and 31; 1866, October 4; 1867, April 4, 5, 7, 8, 9, 11, May 4, 14, 28, 31, June 1, 2, 7, 24), various days having been omitted in consequence of a doubt on the uniformity of the clock-movement of the registering-barrel, which afterwards proved to be unfounded. The results of the comparison were exhibited in curves, engraved copies of which are given in the volume of publication. I expressed my opinion that it was impossible to doubt the general causal connexion of the Galvanic Currents with the Magnetic Disturbances, but that some points yet remained to be cleared up. As soon as circumstances permitted, I undertook the examination of the whole of the Earth-currents recorded during the establishment of the Croydon and Dartford Wires (namely from 1865 April 1 to 1867 December 31), as far as they should appear to bear upon this and similar questions. For this purpose the days of observation were divided by Mr. Glaisher into three groups. Group No. 1 contained days of considerable magnetic disturbance (or days of considerable galvanic disturbance, which are always the same), including, besides the seventeen days above-mentioned, the thirty-six days of the following list :—1865, April 15, 16, 17, 18, 19, May 14, 17, July 7,15, August 14,19, 26, September 8, 16, 28, October 4, 6, 10, 12, 14, November 1; 1866, August 11, 23, September 8, 9,12,13,17,18, 25, October 6, 7,10, 30, November 26 ; 1867, February 8; making in all fifty-three days of considerable magnetic disturbance. Group No. 2 consisted of days of moderate magnetic disturbance, and of these no further notice was taken. Group No. 3 contained the days of tranquil magnetism, and the discussion of these will form the principal part of the present Memoir.

I. Note on an extension of the comparison of magnetic disturbances with magnetic effects inferred from observed terrestrial galvanic currents; and discussion of the magnetic effects inferred from galvanic currents on days of tranquil magnetism

10.1098/rspl.1869.0045 ◽

1870 ◽

Vol 18 (114-122) ◽

pp. 183-185

Keyword(s):

Magnetic Force ◽

The Self ◽

Instrumental Error ◽

Magnetic Disturbance ◽

Magnetic Effects ◽

Royal Observatory ◽

Moderate Disturbance ◽

Magnetic Disturbances ◽

Made In

The author, after referring to his paper in the Philosophical Transactions for 1868 on the comparison of Magnetic Disturbances inferred from Galvanic Currents recorded by the Self-registering Galvanometers of the Royal Observatory of Greenwich with the Magnetic Disturbances registered by the Magnetometers, on 17 days, states that he had now undertaken the examination of the whole of the Galvanic Currents recorded during the establishment of the Croydon and Dartford wires (from 1865 April 1 to 1867 October 24). The days of observation were divided into three groups,—No. I containing days of considerable magnetic disturbance, and therein including not only the 17 days above mentioned, but also 36 additional days, No. 2 containing days of moderate disturbance, of which no further use was made, and No. 3 containing the days of tranquil magnetism. The comparisons of the additional 36 disturbed days were made in the same manner as those of the preceding 17 days, and the inferences were the same. The results were shown in the same manner, by comparison of curves, which were exhibited to the Society. The points most worthy of notice are, that the general agreement of the strong irregularities, Galvanic and Magnetic, is very close, that the galvanic irregularities usually precede the magnetic, in time, and that the northerly magnetic force appears to be increased. The author remarks that no records appeared open to doubt as regards instrumental error, except those of western declination; and to remove this he had compared the Greenwich Curves with the Kew Curves, and had found them absolutely identical.

Comparison of magnetic disturbances recorded by the self-registering magnetometers at the Royal Observatory, Greenwich, with magnetic disturbances deduced from the corresponding terrestrial galvanic currents recorded by the self-registering galvanometers of the Royal Observatory

10.1098/rspl.1867.0048 ◽

1868 ◽

Vol 16 ◽

pp. 249-251

Keyword(s):

The Self ◽

Plane Mirror ◽

Clock Time ◽

Water Pipes ◽

Charles V ◽

Railway Company ◽

The Earth ◽

Royal Observatory ◽

History Of ◽

The author, after adverting to the origin of this branch of science, as commencing (with himself) in communications with Messrs. Edwin and Latimer Clark, but more particularly with Mr. Charles V. Walker, and alluding to the important labours of Mr. W. H. Barlow, Mr. Walker, and Dr. Lamont, proceeds to give the official history of the establishment of the wires and other apparatus necessary for its prosecution at the Royal Observatory. In 1860 and 1861, the author submitted to the Board of Visitors of the Royal Observatory proposals for extending wires from the Royal Observatory in two directions nearly at right angles,—on the second occasion, specifying Croydon and Dartford as terminal points. The Board in 1861 recommended this to the Admiralty, who immediately gave their sanction. The author then applied to the Directors of the South- Eastern Railway for permission to place his wires on their poles, which was granted, at a merely nominal rent. All the wires and labour in mounting them were provided by the Railway Company at cost price, and the insulators were furnished by Messrs. Silver without profit. The wires communicate with the earth at both ends of each by solder-attachment to water-pipes. The author then describes the apparatus made by Mr. Simms for the record of the currents. For each wire the current acts on a galvanometer whose needle-carrier also supports a small plane mirror; and, by proper adjustment of cylindrical lenses, neat spots of light are formed upon a rotating ebonite cylinder, covered with photographic paper and made to revolve (by clockwork) in twenty-four hours. With angular motion of the galvanometer, the spot of light moves. The zero of measure is obtained by interrupting the wire-circuit. The zero of time is obtained by interrupting the light and observing the corresponding clock-time. Other adjustments have received great attention.

XXVIII. On the nature of the forces concerned in producing the greater magnetic disturbances

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1862.0031 ◽

1862 ◽

Vol 152 ◽

pp. 621-638 ◽

Cited By ~ 3

Keyword(s):

Royal Society ◽

The Other ◽

Iron Core ◽

Secondary Currents ◽

The Earth ◽

Other Hand ◽

Previous Communication ◽

Abrupt Changes ◽

1. In a previous communication submitted to the Royal Society on June 28th, 1861, and since published in their Transactions, I ventured to make a suggestion regarding the nature of that connexion which subsists between magnetic disturbances, earth-currents, and auroras. In this hypothesis the earth was viewed as similar to the soft iron core of a Ruhmkorff’s machine, in which a primary disturbing current was supposed to induce magnetism. Earth-currents and auroras, on the other hand, were viewed as induced or secondary currents, caused by the small but abrupt changes which are constantly taking place in the strength of the primary disturbing current, these changes being very much heightened in effect by the action of the iron core, that is to say, of the earth.

A probable cause of the Yearly variation of magnetic storms and auroræ.

10.1098/rspl.1904.0086 ◽

1905 ◽

Vol 74 (497-506) ◽

pp. 90-95 ◽

Cited By ~ 1

Author(s):

Joseph Norman Lockyer ◽

William J. S. Lockyer

Keyword(s):

Seasonal Variation ◽

Atmospheric Pressure ◽

The Sun ◽

Magnetic Disturbance ◽

Yearly Variation ◽

The Earth ◽

Yearly Change ◽

Meteorological Elements ◽

Considerable Period ◽

The ordinary meteorological elements, such as atmospheric pressure, temperature, etc., have a yearly change satisfactorily explained as due to changes of the position of the earth’s axis in relation to the sun, or, in other words, the variation of the sun’s declination. There are, however, other phenomena, such as magnetic disturbances and auroræ, which have been explained differently. Thus, in regard to this seasonal variation Mr. Ellis has written, “The related physical circumstance is that at the equinoxes, when disturbance is more frequent, the whole surface of the earth comes under the influence of the sun, whilst at the solstices, when magnetic disturbance is less frequent, a portion of the surface remains for a considerable period in shadow.”

XXII. An improved solution of a problem in physical astronomy; by which, swiftly converging series are obtained, which are useful in computing the perturbations of the motions of the Earth, Mars, and Venus, by their mutual attraction. To which is added an appendix, containing an easy method of obtaining the sums of many slowly converging series which arise in taking the fluents of binominal surds, &c. In a letter to the Rev. Nevil Maskelyne, D. D. F. R. S. and Astronomer Royal

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1798.0023 ◽

1798 ◽

Vol 88 ◽

pp. 527-566

Keyword(s):

Royal Society ◽

Easy Method ◽

Strong Argument ◽

Mutual Attraction ◽

The Earth ◽

Royal Observatory ◽

The Subject ◽

The Many ◽

Nevil Maskelyne

Reverend Sir, Such is the subject of the inclosed paper, and such the reputation for skill and industry, which the many valuable papers you have communicated to the Royal Society, and your other learned works, have justly procured to you, that it could not with more propriety be submitted to the judgment of any other person than yourself, even if the writer of it were a stranger to you. But there are circumstances which render my presenting it to you, in some measure, a duty. I had the advantage of being, for some years, your Assistant in the Royal Observatory at Greenwich; during which time, you made the important observations on the mountain Schehallien , in Scotland, which afford an ocular demonstration of the attraction of that mountain, and a strong argument for the general attraction of matter, a subject nearly connected with that of the following pages; and it was from you that I received the problem of which you will here find an improved solution.

IV. On the meteorological results shown by the self-registering instruments at Greenwich during the extraordinary storm of October 30,1863

10.1098/rspl.1863.0010 ◽

1864 ◽

Vol 13 ◽

pp. 19-21

Keyword(s):

Royal Society ◽

The Self ◽

Royal Observatory ◽

Meteorological Instruments

In the year 1841 Osier’s anemometer was erected at the Royal Observatory, Greenwich, and from that time, up to the year 1860, the greatest pressure on the square foot recorded was 25 lbs. In February 1860 one of 28 lbs. was registered, which was the greatest up to October 30 of the present year; on that day a pressure of no less than 291/2 lbs. took place during a heavy squall of wind and rain, which passed over the observatory at 3h. 30m. P. M. At this time, moreover, the readings of the several other self-registering meteorological instruments at the Royal Observatory, Greenwich, exhibited very large changes, and of so remarkable a character, that the Astronomer Royal expressed a wish that I should bring them under the notice of the Royal Society. The following are extracts from the several registers of the day mentioned:- At 6h. A. M., on October 30, the barometer read 29·32 in., and it commenced falling slowly after this time, reaching 29·30 in. at 8h. A. M. The decrease then became more decided, and a steady fall was experienced; 29·10 in. was reached by 01/2h. P. M., and 28·96 in. by 2h. P. M.; from 2h. P. M. to 31/2h. P. M. the decline was very rapid; and the minimum reading, 28·80 in., was reached at the latter time.

Philosophical Transactions of the Royal Society of London. Series A, Containing Papers of a Mathematical or Physical Character ◽

A report on magnetic disturbances in northamptonshire and leicestershire and their relations to the geological structure

10.1098/rsta.1919.0010 ◽

1919 ◽

Vol 219 (570) ◽

pp. 73-135 ◽

Cited By ~ 3

Keyword(s):

Royal Society ◽

Large Scale ◽

Geological Structure ◽

Magnetic Disturbance ◽

British Isles ◽

Magnetic Disturbances ◽

Magnetic Phenomena

During the course of the magnetic re-survey of the British Isles, recently carried out by Mr. G. W. Walker under the auspices of the Royal Society, it was found that Melton Mowbray, Leicestershire, was a centre of pronounced magnetic disturbance, both vertical and horizontal. This result was in conformity with that obtained by Rucker and Thorpe in their surveys carried out 29 and 24 years earlier. So far as is known the only element that gives rise to magnetic phenomena on a large scale is iron. It appeared probable, therefore, that the local disturbances were to be connected with the distribution of iron in the rocks, and accordingly the origins of such disturbances were likely to be intimately related to the geological structure of the district.

IV. Comparison of simultaneous magnetic disturbances at several observatories

Philosophical Transactions of the Royal Society of London. (A.) ◽

10.1098/rsta.1892.0004 ◽

1892 ◽

Vol 183 ◽

pp. 131-139 ◽

Cited By ~ 13

Keyword(s):

Magnetic Storm ◽

Great Difficulty ◽

The Self ◽

Vertical Force ◽

Horizontal Force ◽

Magnetic Disturbance ◽

Scale Reading ◽

Photographic Paper ◽

In my former on Magnetic Disturbances and Earth Currents, which were read at the ngs of the British Association at Swansea in 1880 and at York in 1881, a iparison was made of the declination and the horizontal force traces given by the self-recording instruments at five European stations, also at one station in India, one in China, and one in Australia. An attempt was made to determine the relative amounts of the simultaneous changes at the several observatories by comparing them with one another by means of the scale values of the instruments employed, which were all of the pattern of the self-recording instruments at the Kew Observatory. It was found on comparison that there were great differences in the scale values of the instruments of the same kind at the different observatories, and in some ca here was great uncertainty as to the scale values, because no determination of had recently been made. Hence great difficulty was found in arriving at the meaning of the records which were taken regularly at the different observatories. The comparison was sufficient to show the great importance of adopting the same scale values for the like instruments at all observatories. In my paper a recomendation was made that for horizontal force records a scale value of ·0005 millimetremilligramme for a difference of scale reading of 1 mm. should be adopted as being the most convenient. The same scale value was recommended by Dr. Wild, of the St. Petersburg Observatory, and for the vertical force magnetometer the same scale value might conveniently be adopted. With this scale value the instruments would be sufficiently sensitive to give for a considerable magnetic disturbance changes which are capable of being measured, but yet would not be so sensitive as to send the spot of light off the photographic paper, even in a violent magnetic storm.

XI. On the diurnal and annual inequalities of terrestrial magnetism, as deduced from observations made at the Royal Observatory, Greenwich, from 1858 to 1863; being a continuation of a communication on the diurnal inequalities from 1841 to 1857, printed in the Philosophical Transactions, 1863. With a note on the lunodiurnal and other lunar inequalities, as deduced from observations extending from 1848 to 1863

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1869.0014 ◽

1869 ◽

Vol 159 ◽

pp. 413-424

Keyword(s):

Royal Society ◽

Principal Part ◽

General Character ◽

Terrestrial Magnetism ◽

Royal Observatory ◽

Mean Time ◽

Made In

The paper which I have the honour now to submit to the Royal Society is similar, in its general character, to that which was printed by the Society in the Philosophical Transactions for 1863, as containing in a contracted form the results of very extensive observations which have been printed, and of detailed calculations founded on them which are prepared for printing, in the legitimate organ of publication of the observations made in the Royal Observatory. For the principal part of the work, the results are here exhibited to the eye in the shape of diagrams. The instruments employed are precisely the same which were used in the second part of the former investigation, from 1848 to 1857, mounted in the same place, and treated in the same manner; and the observations are reduced by application of the same formulæ. The only difference in the form of exhibition is, that Greenwich Mean Time is here exclusively adopted instead of Göttingen Mean Time, which was used in the former paper. It will be remembered that the longitude of Göttingen is 0 h 39 m 46 s. 5 East of Greenwich. The nominal time, therefore, of the occurrence of a phenomenon is less in the results now presented than in those of the former paper; or, the position on the curves of the figures 1, 2, 3, &c. for hours of time is more advanced than in the former paper, by 40 m nearly.

I. Monthly means of the highest and lowest diurnal temperatures of the water of the Thames, and comparison with the corresponding temperatures of the air at the Royal Observatory, Greenwich

10.1098/rspl.1882.0043 ◽

1883 ◽

Vol 34 (220-223) ◽

pp. 275-284

Keyword(s):

Royal Society ◽

The Self ◽

Partial Reduction ◽

Medical Department ◽

Registrar General ◽

Sanitary Condition ◽

Royal Observatory ◽

History Of ◽

Hospital Ships ◽

Made In

In presenting to the Royal Society a partial reduction of the thermometrical observations made in the water of the Thames during a period of thirty-five years, I commence with a brief history of the undertaking and progress of this work. The observations were instituted at the suggestion of the conductors of the Medical Department in the Office of the Registrar-General of Births, Deaths, and Marriages, with the view of supplying some knowledge of an element which may possibly affect the sanitary condition of the Metropolis. The plan of observations was arranged at the Royal Observatory of Greenwich; and the instruments were procured and mounted, and repaired, when necessary, under the care successively of James Glaisher, Esq., and William Ellis, Esq., Superintendents of the Magnetical and Meteorological Department of the Observatory. The self-recording instruments were attached to the Hospital Ships successively anchored in the Thames, nearly opposite to Greenwich: and their records were read and registered by the medical officers of those ships, and these written registers were transmitted every week to the Royal Observatory. And I cannot too strongly express my sense of the care with which the observations were made, the fidelity with which they were recorded, and the order and regularity with which they were transmitted to the Royal Observatory. The weekly register, when received at the Observatory, was combined with the brief record of other meteorological facts observed at the Royal Observatory, and (with the medical record) was published every week by the Registrar-General.