[4] Saxl is most well known for a series of controversial experiments in which he measured unexpected changes in the period of a torsion pendulum under various conditions.
In 1971, Saxl and Allen published a report of anomalous changes in the period of a torsion pendulum during a solar eclipse in 1970 and hypothesized that “gravitational theory needs to be modified”.
[3][8] None of the effects observed by Saxl and Allen have obvious explanations in terms of well-established theories of gravity and electromagnetism.
Although more subtle explanations, still using conventional physical theory, have been proffered[8][9] there does not appear to be general agreement as to the cause of the anomalies.
Saxl and Allen's claim that general relativity must be modified, and earlier claims of a similar nature by Allais based on observations of anomalies in the behaviour of a paraconical pendulum, have not won acceptance by the physics community, and recent attempts to reproduce the phenomena have not been successful.