Discussion of “Some comments on the results obtained with the Cambridge pendulum apparatus in North America”
The Cambridge pendulums were used in Australia by the Bureau of Mineral Resources, Geology and Geophysics during 1950-51. A statistical analysis has been made of the periods observed, and this will be published as part of a report on the survey. However, some of the conclusions reached are relevant to Gilbert's paper and to Garland's discussion.In the Australian survey, six pendulums (1A, 1B, 1C, 6A, 6B and 6C) were used. Set 1 pendulums were used at Melbourne only; Set 6 were used at Melbourne and also at 58 field stations throughout Australia. A set of observations with one set of pendulums normally comprised two swings with pendulums A and B together, and two swings with pendulums A and C together. Six sets of observations were made at Melbourne with each set of pendulums, at intervals throughout the survey. A series of two or more swings with one pair of pendulums is referred to as a half-set of observations.