Investigations on the field of gravity in Polish tidal laboratories

Presently there are two laboratories in Poland investigating field of gravity. The Geodynamic Laboratory of Space Research Centre in Ksiaz is placed in the south-western part of Poland in horizontal galleries built in slope of the valley. In 1974 in the laboratory the measurements carried out with help of two quartz-horizontal pendulums equipped with photographic system of registration were begun. In 2002 in the laboratory the long water-tube tiltmeter was built. It is consisted of two perpendicular tubes 65- and 83-meter long, partially filled with water. In 2007 in the laboratory the relative gravimeter LaCoste&Romberg G-648 was installed. The Gravimetric Laboratory of Astro-Geodetic Observatory in Józefosław is placed in central part of Poland. It has been investigated tidal gravity changes since 1993 using first LC&R model G gravimeter, then D-model. Since 2001 laboratory is equipped with LC&R ET-26 meter. In 2005 the laboratory was equipped with FG5-230 gravimeter for monitoring of the absolute gravity variations. The paper presents current state-of-art of the researches aimed at investigation on field of gravity carried out by Polish scientific institutions