Effect of the solar eclipse on the period of a torsion pendulum

During the solar eclipse of 22 July 1990 in Finland the period of a torsion pendulum was measured. In previous experiments of this kind [Phys. Rev. D 3, 823 (1971)] a considerable increase was found in the period of the pendulum during the solar eclipse. In our experiment, however, no significant change in the period was observed. The relative change in the pendulum's period associated with the eclipse was found to be less than 4.3×${10}^{-6\mathrm{}}$ (90% confidence).