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composed of qualified representatives of the levelling organizations
of the different European countries, to undertake a simultaneous
adjustment of the European levelling networks on the basis of gravi
tational potential
that European countries should be invited to designate their best
qualified representatives, on the scale of one or two per country,
to take part in this commission.
4.International Latitude Service
The I.U.G.G. recommends
1) that no fundamental change be made in the functioning of the
International Latitude Service, until the completion of the reduction
of the observations which will be carried out during the International
Geophysical Year;
2) that, from 1955, the observations by the stations of the Inter
national Latitude Service be made on 12 groups of 6 pairs of stars
each (6 groups being observed each night corresponding to 6 hours
of observation) in the selection of new pairs, the stars fainter than
the 7th magnitude should be eliminated as far as feasible
3) that, during the International Geophysical Year, Photographic
Zenith Tubes and Dan jon astrolabes be used at stations others than
those of the International Latitude Service, and also, when possible,
at some of these stations
4) that Dan jon astrolabes be used during the International Geo
physical Year, in equatorial countries and especially at Quito (Ecua
dor) and in the Belgian Congo, in view of simultaneous determina
tions of the latitude and of the local time.
5.Time signals
The I.U.G.G., considering that continuous signals in Universal Time
are more and more frequently used, and that very important pro
gresses have been made thereby in the determination of geographical
positions in the field, notes with satisfaction that, in several countries,
devices have been produced for the comparison of such signals with
mean time chronometers, hopes that such studies and developments
will be prosecuted in the same way, and recommends to the various
nations to hint their Geodetic Services to develop such processes and
methods which will permit, at such simple field stations where neither
recording chronographs nor any of the above-mentioned devices are
available, to compare acoustically time signals and chronometers,
without recurring to the use of rhythmic signals, the emission of
which is a burden for the Time Signals Broadcasting Stations and
which might be discontinued.
The use of a second chronometer with a different rate, would per
mit a double system of coincidences: 1. with the time signals and
2. with the master chronometer, and this seems to be a satisfactory
solution of the problem.
