International Geodetic Association Research Articles

The International Association of Geodesy: from an ideal sphere to an irregular body subjected to global change

Abstract. The history of geodesy can be traced back to Thales of Miletus (∼600 BC), who developed the concept of geometry, i.e. the measurement of the Earth. Eratosthenes (276–195 BC) recognized the Earth as a sphere and determined its radius. In the 18th century, Isaac Newton postulated an ellipsoidal figure due to the Earth's rotation, and the French Academy of Sciences organized two expeditions to Lapland and the Viceroyalty of Peru to determine the different curvatures of the Earth at the pole and the Equator. The Prussian General Johann Jacob Baeyer (1794–1885) initiated the international arc measurement to observe the irregular figure of the Earth given by an equipotential surface of the gravity field. This led to the foundation of the International Geodetic Association, which was transferred in 1919 to the Section of Geodesy of the International Union of Geodesy and Geophysics. This paper presents the activities from 1919 to 2019, characterized by a continuous broadening from geometric to gravimetric observations, from exclusive solid Earth parameters to atmospheric and hydrospheric effects, and from static to dynamic models. At present, we identify geodesy as the discipline of quantifying global change by geodetic measurements.

Letters from Carlos Ibáñez e Ibáñez de Ibero to Aimé Laussedat: new sources for the history of nineteenth century geodesy

Recently found letters written by Carlos Ibanez e Ibanez de Ibero (1825–1891), first president of the International Geodetic Association, to geodesist–photogrammetrist Aime Laussedat (1819–1907) are discussed. The contents of these epistolary conversations reflect their personal preoccupation with solving the geodetic problems of the time (1857–1889) and their desire to develop and propagate geodetic knowledge across all international boundaries.

The International Association of Geodesy 1862 to 1922: from a regional project to an international organization

Geodesy, by definition, requires international collaboration on a global scale. An organized cooperation started in 1862, and has become today’s International Association of Geodesy (IAG). The roots of modern geodesy in the 18th century, with arc measurements in several parts of the world, and national geodetic surveys in France and Great Britain, are explained. The manifold local enterprises in central Europe, which happened in the first half of the 19th century, are described in some detail as they prepare the foundation for the following regional project. Simultaneously, Gauss, Bessel and others developed a more sophisticated definition of the Earth’s figure, which includes the effect of the gravity field. In 1861, the retired Prussian general J.J. Baeyer took up earlier ideas from Schumacher, Gauss, Struve and others, to propose a Central European Arc Measurement in order to study the figure of the Earth in that region. This led to a scientific organization, which soon extended from Central Europe to the whole continent and later to the globe, and changed its name in 1886 to ‘Internationale Erdmessung’ (International Geodetic Association). The scientific programme also widened remarkably from more local studies based on geometric data to regional and global investigations, with gravity measurements as an important source of information. The Central Bureau of the Internationale Erdmessung was hosted at the Prussian Geodetic Institute in Potsdam, and with Baeyer as Director, developed as an efficient tool of the Association. The scientific research extended and deepened after 1886, when F.R. Helmert became Director of the Central Bureau. A stronger international participation then took place, while the influence of the German states reduced. Of great practical importance were questions of standardization and reference systems, but first attempts to interpret gravity field variations and to monitor geodynamic phenomena by geodetic methods indicated future tendencies. With the First World War and the expiry of the last international convention in 1916, the international cooperation within the frame of the Association practically came to an end, which ended the first epoch of the Association. Nevertheless, due to the strong commitment of two scientists from neutral countries, the International Latitude Service continued to observe polar motion and to deliver the data to the Berlin Central Bureau for evaluation. After the First World War, geodesy became one of the founding members of the International Union for Geodesy and Geophysics (IUGG), and formed one of its Sections (respectively Associations). It has been officially named the International Association of Geodesy (IAG) since 1932.

The PZT and Astrolabe Programs

The first Photographic Zenith Tube (PZT) of the U. S. Naval Observatory was designed by F. E. Ross. This instrument was based on the reflex zenith tube of Sir George Airy before 1854. This PZT was built with -funds from the International Geodetic Association. Ross PZT was used at the Gaithersburg, Maryland, station, of the International Latitude Service from 1911 to the end of 1914 by the U.S. Coast and Geodetic Survey.

The international geodetic association (die internationale erdmessung) and its predecessors

The international geodetic association (die internationale erdmessung) and its predecessors

New comparisons of the invar wires of Mexico

The geodetic bases of Mexico hare been measured, since the year 1908, with wires of invar steel, 24 meters long, stretched in a free catinary and subjected to a tension of ten kilograms. The first base measured with these wires was that of La Cruz, in Tamaulipas, 40 kilometers long, and the results of this measurement were set forth in full detail at the meeting of the International Geodetic Association in Hamburg in 1912.

Report of the section of geodesy

As is well known, the geodesists of the world have maintained for a number of years an association called the International Geodetic Association. At its last meeting at Hamburg, Germany, in 1912, the fiftieth anniversary of the Association was celebrated. That Association had held triennial conventions for the purpose of bringing together representative geodesists from the twenty or more adhering countries.That the International Geodetic Association and its conferences were of great benefit to the science of geodesy is indicated by the fact that practically all of the geodetic work done throughout the world since the organization of the Association has been of such a high standard that it has not had to be duplicated. These beneficial results have been largely due to the personal contact of the geodesists with each other at the triennial conventions and to the efforts of committees and rapporteurs dealing with the various branches of geodesy, and of the officials of the association.

University and Educational Intelligence

CAMBRIDGE.-A memorandum emphasising the urgency of making formal provision for the encouragement of the study of geodesy and geodynamics in the University, and recommending the early establishment of a readership in these subjects if a suitable endowment can be obtained, has been submitted by the Special Board for Mathematics to the General Board of Studies. The latter has reported that it fully concurs in the importance of the early establishment of such a readership. In its memorandum the Special Board gives reasons why special provision and formal recognition for geodesy and geodynamics is particularly called for at the present time in the. University. The progiess on the theoretical side of the science of the figure of the earth has been promoted in the past very largely by investigators belonging to Cambridge in connection with the scientific problems presented both by the British and by the Indian Surveys, trigonometrical and gravitational. More recently the interconnection of the Surveys of different nations has made the subject an international one, and for the last twenty years the headquarters of the International Geodetic Association, supported by subventions from the various Governments, has been at Potsdam. Reconstruction is called for in the near future, and this country ought to be in a position to resume a large share in the direction. The establishment of a British Imperial Geodetic Institute, with State endowment, is now being urged by responsible scientific bodies, and some institution of the kind will be necessary. Whatever arrangements may be made on the technical and administrative side, the theoretical side, which is the foundation of all progress, is a subject of pure mathematical and dynamical science, and can best be advanced by the universities. In order for Cambridge to retain her historical position in the advance of this important science, and to take part in the training of the men who will be required for its prosecution, some special provision and formal recognition for the subject are called “for under modern conditions. .

The Survey Link Connecting the Triangulations of India and Russia 1

AT the meeting of the International Geodetic Association held in London in 1909 the way was cleared for the completion of a connecting link between Indian and Russian triangulations which would carry scientific measurement from Cape Comorin to Petrograd. This necessitated the extension of a geodetic series across some of the highest and most unapproachable of the snow-capped ranges in the northern Himalayan system. Between Gilgit and Salisbury Peak on the Nicolas (Russian spelling) range of the Pamirs there intervene about 100 miles of inconceivably wild and rugged mountain country distinguished by groups of peaks running to altitudes of more than 20,000 ft. and seamed with a most amazing-series of waterways containing the biggest glaciers in the world. Salisbury Peak, near the western end of the Pamir boundary between Russia and Afghanistan, looks southwards across the valley of the river Ab-i-Panja (flowing westward to the Oxus and skirting the southern foot of the Nicolas range) on to the great ridge of the Hindu Kush. From the Hindu Kush southward to the Gilgit river flow three great mountain streams, which afford the only possible approaches northward, i.e. the Yasin, the Ashkuman, and the Hunza.

On the Body Tides of the Earth, A Proposal for the International Geodetic Association

On the Body Tides of the Earth, A Proposal for the International Geodetic Association

The Meeting of the International Geodetic Association in London and Cambridge

THE meeting which began in London on Tuesday, September 21, and ended in Cambridge on September 30, has been notable in several respects. Great Britain joined the International Geodetic Association only twelve years ago. The triennial meeting has been held this year for the first time in England, and for the first time Greater Britain has been represented by special delegates from the Governments of India, Australia, and Canada; Chili has become a member of the association and sent a representative; and the Egyptian Government has been represented by one of the British officers of the Survey Department. The London meeting marks, then, a broadening of the interests of the association on the political and administrative side; on the scientific side it has been remarkable for the extremely interesting reports upon the special problems of the internal constitution of the earth and the lunar earth-tides.

New study of the polar motion and z for the interval 1890.0–1908.5. (A proposal for the International Geodetic Association)

Astronomische NachrichtenVolume 181, Issue 24 p. 389-402 Article New study of the polar motion and z for the interval 1890.0–1908.5. (A proposal for the International Geodetic Association) Hisashi Kimura, Hisashi Kimura Mizusawa, International Latitude ObservatorySearch for more papers by this author Hisashi Kimura, Hisashi Kimura Mizusawa, International Latitude ObservatorySearch for more papers by this author First published: 1909 https://doi.org/10.1002/asna.19091812402Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume181, Issue241909Pages 389-402 RelatedInformation

Geodetic Investigations in the United States 1

THE report of the U.S. Coast and Geodetic Survey for 1907 has just been received. For the details of the extensive cartographic work of the bureau in the United States proper, Alaska, Porto Rico, and the Philippines, as well as for the account of the progress of the primary triangulation and levelling of precision, the report itself must be consulted. Certain important work of the survey receives bare mention, as, for instance, the results of the investigation of the earth's figure, based on geodetic operations in the United States. This is owing to the fact that these results were communicated to the International Geodetic Association in a preliminary report which has been published.

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

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.

The International Geodetic Conference at Buda Pest

THE International Geodetic Association held its triennial conference at Buda Pest from September 20 to 28, and I had the honour of serving as the delegate of our Government. By the kindness of the Hungarian Academy the meetings were held in their handsome building, and the arrangements for our reception, which had been made by M. Louis de Bodola, were in every way admirable. Before considering the scientific work of the conference I may mention that the Prime Minister, Dr. Wekerle, invited the members of the “Permanent Commission” to dinner, and that the Archduke J oseph afterwards received all the delegates at the palace. On subsequent days the Burgomeister of Buda Pest gave a dinner in our honour, as also did Count Albert Apponyi, Minister of Public Instruction.

VIII. On the intensity and direction of the force of gravity in India

Between 1865 and 1873 observations were taken at 31 stations in India by Captains Basevi and Heaviside with the Royal Society’s seconds pendulums. The results were published in Vol. V. of the ‘Account of the Operations of the Great Trigonometrical Survey of India,’ and have been subsequently discussed by many authorities. Captain Basevi expressed his results in terms of N, the number of vibrations of the mean pendulum observed in a mean solar day. The International Geodetic Association show their results in dynes, and it is desirable that we should follow their example. We have, therefore, to change the notation employed by our predecessors.

PROGRAMME OF THE INTERNATIONAL GEODETIC ASSOCIATION FOR OBSERVING VARIATIONS OF LATITUDE

PROGRAMME OF THE INTERNATIONAL GEODETIC ASSOCIATION FOR OBSERVING VARIATIONS OF LATITUDE

The General Conference of the International Geodetic Association at Stuttgart, October 3-12, 1898

The General Conference of the International Geodetic Association at Stuttgart, October 3-12, 1898

Geographical Notes

AT the meetings of the International Geodetic Association at Geneva the representatives of the various countries present reported on the works executed by their governments. We are pleased to learn of a resolution of the French Ministry to proceed to a new levelling of precision of the first order on a length of 17,000 kilometres; a levelling of the second order will follow on a length of 800,000 kilometres. The operations to connect Spain and Algeria, to which we have referred were also described. The next meeting will be held at Munich in the autumn of 1880.

Geographical Notes

THE Permanent Commission of the International Geodetic Association, presided over by General Ibanez, has decided to meet on the i6th inst. at Geneva, on the invitation which has been addressed to it by the Government of the little republic. The first official sitting is to be at 2 o'clock, on the loth, at the Hotel de Ville of Geneva, in the room known as “the Alabama.” In the evening Prof. E. Plantamour will hold a reception. The official sittings will continue daily at 10 A.M., in the same room, to the end of the week, interrupted on the 18th by a procession of steamers on the lake, which will occupy the whole of the day. On the evening of the 17th the Commissioners are invited to dine by the Council of the State of Geneva, and on the afternoon of the igfh there will be a reception at Secheron by Prof. Plantamour. The programme of the session comprises: The reports of the Permanent Commission and the Central Bureau, the report of the Commission appointed at Hamburg in 1877 to consider the proposals of Lieut.-Col. Adan; the choice of the place of meeting of the sixth conference, and the appointment of special reporters to record the proceedings (1) As to determinations of latitude, longitude, and azimuth; (2) Triangulations and calculations of compensation of the networks; (3) Levelling operations and result of mareographic operations; (4) Measurements of the intensity of gravitation; (5) Publications relating to the measurement of degrees in Europe.