The variations of gravity were measured with a high precision LaCoste-Romberg D gravimeter during a total solar eclipse to investigate the effect of a solar eclipse on the gravitational field. The observed anomaly $(7.0\ifmmode\pm\else\textpm\fi{}2.7)$$\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}$ ${\mathrm{m}/\mathrm{s}}^{2}$during the eclipse implies that there may be a shielding property of gravitation.

> THE Gyirong-Lugu gravity profile in western Xizang Plateau was carried out by Institute ofGeophysics,Chinese Academy of Sciences in 1994—1995.The data of this gravity profile fillthe gaps in the research of gravity field of western Xizang Plateau and provide basic informa-tion for the study of the whole structure and dynamical mechanism of Xizang Plateau.

We have previously reported that the circling phenotype of thechakragatimouse segregates with the transgene integration event as an autosomal recessive trait. It was unclear, however, whether the phenotype was linked to the transgene integration point nearD16Ros1or to a potential disruption atD16Ros2,10 cM away. We report here that animals recombinant betweenD16Ros1andD16Ros2,homozygous for the transgene insertion atD16Ros1,but wildtype forD16Ros2,do indeed show the phenotype. We conclude that any potential disruption at theD16Ros2locus is not responsible for the circling phenotype. We further show that recombination betweenD16Ros1andD16Ros2occurs at a greatly reduced level in thechakragatimouse compared to wildtype strains. Detailed genetic analysis of recombinants indicates that the proximal-most 4.5 cM shows no recombination in over 1400 meioses. We propose that this is due to an inversion in this region, and we genetically define the proposed distal inversion break point to a 1.3-cM region betweenD16Mit63andD16Mit169.

In a tower test of Newton's inverse-square law of gravitation we found no evidence for the non-Newtonian force, and the accuracy of the experiment constrains the Yukawa potential coupling constant absolute value of alpha to be less than 0.0005.