scholarly journals I. On periodical laws in the larger magnetic disturbance

1853 ◽  
Vol 143 ◽  
pp. 165-177
Keyword(s):  
Royal Society ◽  
Magnetic Disturbance ◽  
Cape Of Good Hope ◽  
Magnetic Declination ◽  
The Press ◽  
Meteorological Observations ◽  
St Helena ◽  
Magnetic Disturbances

Having submitted the hourly observations of the magnetic declination made at the St. Helena and the Cape of Good Hope Observatories to a course of examination similar to that undertaken by Colonel Sabine for Toronto and Hobarton, and published by him in the Philosophical Transactions, Part I. for 1851, and Part I. for 1852, also in Vol. II. Magnetical and Meteorological Observations at Hobarton, and VoI. II. Magnetical and Meteorological Observations at Toronto (now in the press), with the object of investigating some of the laws which govern the occurrence of the larger magnetic disturbances, I have found that at these two stations, as well as at the two others, the evidence is complete of the existence of laws of a periodical character: the facts appear to be important materials towards elucidating the general laws of disturbances, and I therefore venture to communicate them to the Royal Society. The observations which have been examined are comprised between September 1842 and September 1847 at St. Helena, and between July 1841 and July 1846 at the Cape of Good Hope; these periods include all the hourly observations that could be made available for discussion.

scholarly journals Remarks on M. De la Rive’s theory for the physical explanation of the causes which produce the diurnal variation of the magnetic declination. In a letter to S. Hunter Christie, Esq., Sec. R. S., from Lieut.-Col. Sabine, For. Sec. R. S. Communicated by S. Hunter Christie, Esq

1851 ◽  
Vol 5 ◽  
pp. 821-825
Keyword(s):  
Diurnal Variation ◽  
Royal Society ◽  
Exact Methods ◽  
Physical Explanation ◽  
Cape Of Good Hope ◽  
Magnetic Declination ◽  
St Helena ◽  
Physical Principles ◽  
Magnetic Observatories ◽  
Recent Establishment

My dear Sir, The Annales de Chimie et de Physique for March last contains a letter from M. De la Rive to M. Arago, in which a theory is proposed, professing to explain on physical principles the general phenomena of the diurnal variation of the magnetic declination, and, in particular, the phenomena observed at St. Helena and at the Cape of Good Hope, described in a paper communicated by me to the Royal Society in 1847, and which has been honoured with a place in the Philosophical Transactions. Although I doubt not that the inadequacy of the theory proposed by M. De la Rive for the solution of this interesting problem will be at once recognised by those who have carefully studied the facts which have become known to us by means of the exact methods of investigation adopted in the magnetic observatories of recent establishment, yet there is danger that the names of De la Rive and Arago, held in high and deserved estimation as authorities on such subjects, attached to a theory, which moreover claims reception on the ground of its accordance with “well-ascertained facts” and “with principles of physics positively established,” may operate prejudicially in checking the inquiries which may be in progress in other quarters into the causes which really occasion the phenomena in question; I have thought it desirable therefore to point out, in a very brief communication, some of the important particulars in which M. De la Rive’s theory fails to represent correctly the facts which it professes to explain, and others which appear to me to be altogether at variance with, and opposed to it.

scholarly journals On periodical laws in the larger magnetic disturbances

1854 ◽  
Vol 6 ◽  
pp. 287-289
Keyword(s):  
Cape Of Good Hope ◽  
Magnetic Declination ◽  
St Helena ◽  
Magnetic Disturbances

In this communication the author has arranged, in tables, the disturbances of the magnetic declination at St. Helena and the Cape of Good Hope, for the purpose of exhibiting the systematic laws by which those phenomena are regulated, which were long described as irregular variations, because they were of occasional and apparently uncertain occurrence. The frequency of the disturbances, and their amount, whether viewed separately as easterly or westerly movements, or as general abnormal variations (easterly and westerly being taken together), is shown to be dependent upon the hour of the day, the period of the year, and upon the year of observation.

scholarly journals On the annual variation of the magnetic declination, at different periods of the day

1854 ◽  
Vol 6 ◽  
pp. 73-74
Keyword(s):  
Annual Variation ◽  
Graphical Representation ◽  
Horizontal Line ◽  
Annual Variations ◽  
Cape Of Good Hope ◽  
Magnetic Declination ◽  
Annual Range ◽  
The Hours ◽  
The Mean ◽  
St Helena

In this communication the author has arranged and presented together the Annual variations which the magnetic declination undergoes at every hour of the day at the four Colonial Observatories established by the British government, at Toronto, Hobarton, the Cape of Good Hope and St. Helena. This has been done by means of a graphical representation, in which the annual variations at every hour are shown by vertical lines varying in length according to the amount of the range of the annual variation at each hour; each line having also small cross lines marking the mean positions of the several months in the annual range. The mean declination in the year at the respective hours is marked by a horizontal line which crosses all the verticals at each station. The hours are those of mean solar time at each station, the day commencing at noon.

scholarly journals 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

1870 ◽  
Vol 160 ◽  
pp. 215-226 ◽  
Keyword(s):  
Royal Society ◽  
Principal Part ◽  
The Self ◽  
Magnetic Disturbance ◽  
Magnetic Effects ◽  
The Earth ◽  
Royal Observatory ◽  
Magnetic Disturbances

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.

scholarly journals II. Results of hourly observations of the magnetic declination made by Sir Francis Leopold M‘Clintock, R. N., and the Officers of the Yacht 'Fox,' at Port Kennedy, in the Arctic Sea, in the winter of 1858-59; and a comparison of these results with those obtained by Captain Maguire, R. N., and the Officers of H. M. S. 'Plover,' in 1852, 1853, and 1854, at Point Barrow

1864 ◽  
Vol 13 ◽  
pp. 84-86
Keyword(s):  
Royal Society ◽  
The Arctic ◽  
Magnetic Declination ◽  
Arctic Sea ◽  
Meteorological Observations

When about to undertake a voyage to the Arctic Sea in 1857, in the yacht ‘Fox,’ in search of the ships of Sir John Franklin’s expedition. Captain M'Clintock requested that the Royal Society would supply him with such information and instructions as might enable him to make the best use of the opportunity which the voyage was likely to afford for the prosecution of magnetical and meteorological observations.

XIX. Meteorological observations made on board Her Majesty's {hired) Bark Pagoda, from January 10 to June 20, 1845, between —20° and —68°, and 0° and 120° east longitude

1846 ◽  
Vol 136 ◽  
pp. 433-440 ◽  
Keyword(s):  
Royal Society ◽  
The State ◽  
Cape Of Good Hope ◽  
The Hours ◽  
Meteorological Observations ◽  
Meteorological Instruments

As much interest has been taken of late in the state of the barometer in high southern latitudes, the Expedition sent last year from the Cape of Good Hope to complete the magnetical observations made by Sir J ames C. Ross in those latitudes, was supplied with a barometer and other meteorological instruments, and directed to make meteorological as well as magnetical observations. I have now the honour of laying before the Royal Society the observations made during that Expedition. They were taken daily at the hours of 3 and 9 a.m., 3 and 9 p.m., noon, and midnight, by the officers of the ship during their respective watches. Nothing could exceed the zeal with which the officers entered into all the objects of the Expedition, and the attention and care they took in the observations they had to make.

scholarly journals II. Determination of the magnetic declination, dip, and force, at the Fiji Islands, in 1860 and 1861

1862 ◽  
Vol 11 ◽  
pp. 481-486
Keyword(s):  
Royal Society ◽  
Magnetic Observatory ◽  
Magnetic Declination ◽  
Fiji Islands ◽  
St Helena

[Note by the Communicator.— Colonel Smythe is known to magneticians as having been Director of the Magnetic Observatory at St. Helena from 1842 to 1847. Being about to proceed, in December 1859, on a Government Mission to the Fiji Islands, which would require his residence there for some months, he addressed a letter to the Council of the Royal Society expressing his readiness to make any scientific observations that might be suggested to him as likely to be useful in a part of the globe hitherto so little known.

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

1919 ◽  
Vol 219 (570) ◽  
pp. 73-135 ◽  
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.

scholarly journals On some conclusions derived from the observations of the magnetic declination at the Observatory of St. Helena

1856 ◽  
Vol 7 ◽  
pp. 67-82
Keyword(s):  
Royal Society ◽  
Magnetic Declination ◽  
St Helena ◽  
Magnetic Observatories

The author commences with the following preliminary remarks:— “The part taken by the Royal Society in promoting, by its influence with Government, the establishment of the Colonial Magnetic Observatories, and in drawing up instructions for the guidance of those who were employed in them, makes it the duty of the person charged with their superintendence, to spare no pains to place before the Fellows, on suitable occasions, the results of researches designed to obtain a foundation of facts, on which a correct theory of the magnetic variations might be framed, and an insight be gained into the nature of the physical agency by which they are produced.

Sign in / Sign up

Export Citation Format

Share Document