The International Association of Geodesy can trace its roots
back to the early 19th century, a time of great progress in
geodesy, when Bessel and Gauss made important contributions to
the science. One of Bessel's pupils was J.J. Baeyer, who
later became an officer of the Prussian General Staff. In 1861
General Baeyer wrote a report suggesting that the states
of Europe should work together on the measurement of the size and
shape of the earth and proposing methods to achieve this aim. The
King of Prussia accepted the report and invited the countries
concerned to subscribe to the plan.
By 1862 the following countries had agreed to participate:
Denmark, Saxe-Gotha, the Netherlands, Russia (for Poland),
Switzerland, Baden, Saxony, Italy, Austria, Sweden, Norway,
Bavaria, Mecklenburg, Hanover and Belgium (15).
The first International Geodetic Conference met
at Berlin in 1864. The conference set up a structure and made
decisions whose influence is still to be seen in the I.A.G.
statutes of today. The conference established two powerful
bodies, the Permanent Commission and the
Central Bureau. The Permanent Commission was
to be the "supreme, standing scientific agency of the
international geodetic association". The Central Bureau, the
executive agency of the Permanent Commission, was to receive
reports each year from member states on the results of the work
as well as proposals for new projects, and to submit them to the
Permanent Commission "for evaluation and approval". The Central
Bureau was to compile the individual reports into a single
general report, and to perform the work and conduct the
negotiations to achieve uniformity in geodetic and astronomical
measurements. The Conference also made a number of scientific
recommendations, amongst others, measures to establish Bessel's
toise as the fundamental length standard and to encourage
measurement of levelling networks with properly determined datum
points. A Permanent Committee of seven members was
The Central Bureau was set up in 1866 at the expense of the
Prussian state, within the Geodetic Institute at Berlin. General
Baeyer, Director of the Institute, was also appointed Director of
the Bureau. In 1867, at the Second General Conference, the
association's name, previously Mitteleuropäische
Gradmessung, was changed to Europäische
Gradmessung, with the acceptance of Spain and Portugal as
members. This Conference also dealt with weights and measures,
recommending the adoption of the metric system and the
establishment of an international bureau of weights and measures.
[General Baeyers' death in 1885 marked the end of an era.
His successor was the geodesist Dr. F .R. Helmert. There
had been many changes since 1862. The German states had come
together under the German Empire, while in the association the
expenses of the Central Bureau were constantly increasing and the
number of member states was growing. A new convention was drawn
up, signed by 20 European states, to come into force for ten
years from the beginning of 1887. The Central Bureau was to be
supported by contributions from the member states. The convention
conferred intergovernmental status on the association.
The Eleventh General Conference held in Berlin in 1895 drew up
a new International Geodetic Convention. By this
time other countries had joined, in particular the United States
and Japan. Under the convention the Central Bureau was retained,
still attached to the Geodetic Institute at Berlin, and the
contributions for its support were increased. The Permanent
Commission was abolished, replaced by a more representative
General Conference. According to the convention the
"supreme body of the Geodetic Association shall be the General
Conference of the delegates of the Governments concerned."
The text of the convention was ratified by 21 member countries
at the General Conference in Stuttgart in 1898. In 1907 it was
extended for a further ten years. The 50th anniversary
of the association was celebrated at the Seventeenth General
Conference held in Hamburg in 1912. The scientific work of the
association continued to be summarized in the reports of the
Director of the Central Bureau. It is interesting to see the list
of some of the topics reported on by Helmert in the report
submitted to the 1912 conference.
- scientific research, theoretical (Helmert, Bruns,
- scientific publications including a bibliography of geodesy
- coordination of geodetic triangulation, particularly
scientific arc measurements.
- coordinating determinations of the deviation of the vertical
- variations in the axis of rotation of the earth, and the
International Latitude Service.
- gravity measurements, the first world gravity network, and
measurements at sea.
Only two years later, in 1914, World War I broke out and
halted the scientific cooperation among geodesists. Of the
signatories of the convention, only seven remained neutral. These
were dark years for geodesy.
Although the convention extended to the end of 1916, war had
been raging for eighteen months, by then, and scientific
relations had been severed. Many officers of the association had
died, including the President General Bassot of France, in
1917 ; the Vice-President Sir George Darwin (Britain) in
1912 and his successor O. Backlund (Russia) in 1916; and
Helmert, who had been Director of the Central Bureau since
1885, in 1917.
It is remarkable that the association managed to survive and
it did so mainly through the efforts of two geodesists from
neutral nations: R. Gautier of Switzerland and H.G. van
de Sande Bakhuyzen of the Netherlands, who had been secretary
of the association since 1900. After consultation between the
seven neutral members, the Reduced Geodetic Association
among Neutral Nations was established, with
Gautier as President and van de Sande Bakhuyzen as
The Reduced Association aimed to continue the work of the old
association and to prepare for its reestablishment after the war.
The permanent tasks such as the International latitude Service
were continued and some scientific work was pursued.
One of the arrangements of the Reduced Association was to keep
up contact with the Central Bureau, still housed with the
Geodetic Institute of Prussia, now in Potsdam. The Bureau
continued to operate at a reduced level.
Some of the belligerents opposing Germany took exception to
this arrangement, and set out, in 1918, to establish a new
international geodetic association. C. Lallemand sent to
the delegates of all countries of the Entente a draft convention
for a new association, along with a letter complaining vehemently
against the continued connection between the Reduced Association
and the Central Bureau behind a "neutral facade". Gautier
responded in reasoned fashion, arguing against the exclusion of
Germany, Austria and their allies.
However at the conferences in 1918 and 1920 which led to the
creation of International Scientific Unions, no one listened to
Gautier, or even consulted the Reduced Geodetic
Association. Severe obstacles were erected against the membership
of Germany and her allies, that delayed their admission for many
The concept of closer international cooperation of scientific
bodies had been discussed before World War I. Even before the war
had ended a series of conferences was held, culminating in the
Constitutive Assembly of the International Research Council in
Brussels in 1919. This set up the Council and a number of
constituent international scientific unions. Besides the
International Union of Geodesy and Geophysics
(IUGG) there were Unions covering astronomy, chemistry, physics,
radio science, biology, mathematics and others. For each of these
unions, every member country was to set up a National
In the IUGG, Geodesy was one of six sections. An interim
Bureau was set up, to hold office until the first General
Assembly, which was set for April 1922, in Rome. A seventh
section, hydrology, was added at that Assembly. The Geodesy
Section also made amends for the unjustified accusations made
previously against the Reduced Association. Gautier was
elected Vice-President and in this position was able successfully
to transfer the assets and operations of the Reduced Association
to the new Geodesy Section.
The initial statutes, adopted for the twelve years 1919-1931,
had stipulated that only Allied and neutral nations could join
the International Research Councilor its Unions. In 1926 these
membership restrictions were lifted, but serious damage had
already been done: Germany only applied for admission to IUGG in
The new statutes which came into force after 1931 changed the
name of the International Research Council to the
International Council of Scientific Unions (ICSU).
Within the IUGG, the sections became Associations. By 1936 the
Association of Geodesy and others were commonly referred to as
International Associations, but this was not formally ratified
until new Union statutes were adopted in 1946. Since then our
association has been, officially, the International
Association of Geodesy, I.A.G. (Association
Internationale de Géodésie, A.I.G.).
The structure of the Geodesy Section of the IUGG which emerged
after the General Assembly in Rome in 1922, had many features
similar to the I.A.G. structure of today. The Secretariat was
instructed to prepare a set of statutes to present to the next
General Assembly in Madrid in 1924. In the pre-war Geodetic
Association, the scientific activities had centred on one agency,
the Prussian Geodetic I nstitute, and on one person, its
Director. The new organization, though its administration and
coordination was handled by a central secretariat, was to have
its scientific activities decentralized. The Scientific
Commissions were composed of delegates from member countries;
they elected their own presidents.
The 1924 Statutes set up the following structure:
- the Bureau, comprising the President, Vice-President and
Secretary (as at present).
- the Secretariat, responsible for the office administration,
correspondence, arrangements for meetings.
- the Executive Committee, more or less in the form of the
- the Scientific Commissions (now replaced by Special Study
Groups and Commissions, whose functions are described
- the Permanent Commission comprising one delegate from each
member country (in the present structure called the
- the General Assembly, comprising all delegates from member
countries; it was given important powers of voting on finance on
elections, and on scientific activities.
During the General Assemblies there were three types of
presentation: General Reports on matters of wide interest, which
now would perhaps be covered by Commissions; National Reports, to
be published later in the Travaux (Proceedings); and scientific
papers by individuals.
The role of the Section, later the Association of Geodesy had
changed from the pre-World War I period. The original concept was
that of a central office directing and coordinating geodetic
projects through a quasi-governmental association. Since 1922 the
role has been to promote projects rather than direct them and to
ensure good communications between geodesists of different
Activities of the organization between 1922 and 1939 included
publishing the Bulletin Géodésique
regularly, as well as General Reports, National
Reports and an International Bibliography of
Geodesy. Important advances were made in the scientific
sphere. Field work encouraged by the LA.G. included geodetic
connections between countries, and continental and
intercontinental geodetic chains. Hayford's spheroid, the first
international reference surface was adopted in Madrid in 1924.
There were advances, theoretical and practical, in physical
geodesy. Buchwaldt pointed out the importance of Stokes'
theorem, enabling the shape of the earth to be determined from
gravity. Methods for measuring gravity at sea were developed by
Vening Meinesz, gravimeters made their appearance, and
isostatic theory was developed. Simultaneously, de
Graaff-Hunter and Vening Meinesz developed expressions
for deflections of the vertical in terms of gravity
All this activity was again interrupted by war. The I.A.G. was
perhaps more fortunate this time, as the Seventh General Assembly
of IUGG was convening in Washington when World War II broke out.
Many of those attending had to return home in haste, but the
Association was able to make one important decision, namely to
extend the term of the President for the duration of the war. The
Bureau members were F. Vening-Meinesz (Netherlands),
President; W.D. Lambert (U.S.), Vice President; and G.
Perrier (France), Secretary. Activity was restricted during
the war, but publications, notably the Bulletin
Géodésique, were continued.
After the war an Extraordinary General Assembly of the Union
was called in July 1946, to consider new statutes and by-laws.
These were ratified at the first full General Assembly in Oslo in
1948. The IUGG and the I.A.G. have separate sets of Statutes and
By-Laws, but they have always been consistent, and similar in
structure. The statutes and by-laws were further amended at the
General Assembly in Brussels in 1951. They set out the
composition and functions of the Bureau, the
Executive Committee, the Council (the
new name by which the former Permanent Commission was to be
known) and the General Assembly. A new provision
was to limit the term of office-bearers to one period between
Assemblies. Between 1920 and 1946 the Association had only two
office-bearers in each of its main offices. There were only two
presidents, for example: W. Bowie (U .S.) from 1920 to
1933 and F. A. Vening-Meinesz (Netherlands) from
1933-1946. Since 1948, the terms of presidents and other officers
have been limited to one period of three or four years, from one
General Assembly to the next.
There were some minor organizational changes:
- the name of the Secretariat was changed to the Central
Bureau. This is an unfortunate name as it can be confused
with the Bureau. The Central Bureau is the Secretariat, serving
particularly the Bureau and the Executive Committee.
- the Executive Committee was enlarged and given
greater responsibilities, relating to the organization and the
scientific activities of the Association
- the Permanent Commission was renamed the
Council. This body still comprised one delegate per
member country, and was given special tasks in relation to
administrative and financial questions.
- the General Assembly, comprising all delegates
from member countries, retained its important voting powers.
A major innovation of the By-Laws was to divide the scientific
activities of the LA.G. into five Sections. Each
Section covered a defined part of geodesy. In 1952 the Section
titles were: Triangulation, Precise levelling, Geodetic
astronomy, Gravimetry and Study of the geoid. The aim was to
focus on the main interests of geodesy and with the number of
participating geodesists constantly on the increase, to bring
together those who shared special interests. Each Section has a
President and two or more Secretaries. The Section Presidents are
members of the Executive and the Secretaries may attend the
meetings "with voice but without vote."
Within a Section there are normally several Commissions and
Special Study Groups (SSGs). Commissions are established to cover
broad general topics, which wiII be the subject of activity for
an extended period, whiIe SSGs are formed to study specific
scientific topics of current interest. They exist normally for
only one or at most two four-year periods.
In 1971 at the General Assembly in Moscow, the statutes and
by-laws were revised and new definitions of the Sections drawn up
to reflect the changing scope of activities. Again, in 1983, the
statutes and by-laws, after a long and careful review, were again
The most significant change in 1983 was a shift in
responsibility from the General Assembly to the Council, which
now has important voting, elective and financial powers. This
change stemmed from a desire to ensure that all countries have
equitable voting rights on important issues. Under the earlier
rules it was conceivable that the wishes of the majority of
countries could be frustrated in the General Assembly by a large
block of voters from a single country.
The I.A.G. has seen an ever-increasing volume of scientific
activity and innovation in the years since 1945. Particularly
since the advent of earth satellites the pace of progress has
increased. This progress has been aided by the tremendous
advances in technology and in computers. To give an example,
satellites have yielded a model of the earth's gravity field of
unprecedented precision and detail. The remarkable precision in
position fixing has created a new relationship between geodesist
and geophysicist, in which the geodetic observations are of prime
importance in geodynamic interpretations. Theory has not been
neglected and remarkable progress has been made in a number of
theoretical areas such as mathematical methods, collocation,
gravity field models and statistical methods.
In this brief note it is not possible to summarize the
scientific achievements of modern geodesy. What is of
significance is to note that the I.A.G. is aware of the tempo of
progress and is constantly adapting to reflect the current needs.
Mention has already been made of new statutes and by-laws in
1952, then 1971, then 1983. Provision has already been made for
the next Cassinis Committee, named after the I.A.G. President of
1957-1960, to sit in 1987-1991 and to report on further changes
in 1991. Not only this, but the SSGs, the "cutting edge of
geodetic science", are reviewed and renewed every four years, so
that they can fulfil precisely the current needs.
This historical note has been summarized from a more detailed
account written by J.J. Levallois, who was Secretary
General of the Association from 1960 to 1975. Readers are
referred to this account, which is available in the
Geodesist's Handbook of 1980 (pp. 249-313). For
details of the current structure and activities of the
Association, readers are referred to the contents of this
Handbook which includes lists of officers, as well as lists and
descriptions of Sections, Commissions and Special Study Groups.
It is over 120 years since the association of geodesy was first
established. The association has known successes and setbacks in
its time, but has always remained steadfast in its objectives of
fostering the science of geodesy and the dissemination of
information on geodesy. The key role of the I.A.G. is in bringing
together geodesists from all countries, from east and west, from
undeveloped and developed countries. The friendly atmosphere of a
geodetic meeting, whether a full General Assembly or a small
symposium, and the sharing scientific interests, lead to mutual
respect and enduring friendship. These relationships and the
fruitful exchanges of ideas which they create are powerful forces
for progress in geodesy.