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Opslag van reserve-instrumenten in de tropen
4- The I.A.G. having received the report of the special study group
appointed to consider the establishment of a calibration base in Europe,
and considering that at every point on the base observations should
be made with both pendulum and gravimeters, recommends
1) that in the first instance the following European stations should
be selectedHammerfest, Böde, Oslo, Copenhagen, Harzburg, Munich
and Rome
2) that as far as possible both pendulum and gravimeter observa
tions should be carried out over the whole extent of the line according
to the schemeABBA, BCCB, etc.
3) that for the calibration of gravimeters which have only a small
range, the calibration line should be subdivided at intervals of about
20 km
4) that for the control of the main calibration base a second
parallel line should be established, as for example: Edinburg, Tedding-
ton, Paris and Bagnères de Bigorre
5) that interconnection should be made between the calibration base
and the secondary line, as for example
Oslo-Edinburgh
HarzburgParis R UnR Bagnères de Bigorre
CopenhagenTeddington 0me
using both high precision gravimeters and, if possible, pendulums;
6) that in deriving the final calibration of gravimeters the possible
existence of non-linearity of scale and time variations in sensibility
should be taken into consideration
7) that a comparative study should be made of the different meth
ods such as the line and area methods, of adjusting the results and
of calibrating gravimeters using the same data, and
8) that the study group should be maintained in being under the
chairmanship of Prof. Kneissl, in order to give further considera
tion and assistance in connection with the establishment of a European
calibration base.
is mogelijk door een nieuwe door Smiths Aircraft Instruments Ltd.
Cricklewood, London, N.W. 2, ontwikkelde bus, waarin vliegtuig
instrumenten onder de bezwaarlijkste klimatologische omstandigheden
twee jaar goed blijven. Sommige instrumenten moeten en kunnen
periodiek uit de omkapseling worden gehaald om gesmeerd te worden
en daarna weer hierin te worden geborgen.
Als het uitwendige van de bus, na een proef equivalent aan drie
tropische jaren roestvlekken e.d. vertoonde, bleek het inwendige ge
heel ongeschonden. De bus wordt afgesloten met plastic bandhet
inwendige is gecapitonneerd en het voorwerp rust daarin, gewikkeld
in waspapier, dichtgeplakt met een band die een gas afscheidt, waar-
