The measurements of the bases (Warsaw base, Tarnogród base and Częstochowsk base) were made as part of a more complex project ‘RussianScandinavian Arc’ (Struve Geodetic Arc). These measurements were made in Królestwo Polskie (Polish Kingdom), a territory which belonged to the Russian Empire from 1815 till 1917. This territory had gone over to Russia during the socalled Fourth partition of Poland in 1815. The base measurements within the triangulation of Poland were conducted by an outstanding Russian military geodesist, general-lieutenant of The House of Military Topographers, Carl Ivanovich Tenner (born Carl Friedrich Tenner). Carl Tenner suggested that astronomical observations should be done by Adam Prazmowski , a Polish astronomer and Deputy Head of Warsaw Observatory. As it was later reported by Tenner, all work had been successfully done “with all possible thoroughness and precision in accordance with the strict rules of the head of Pulkovo Observatory, Vasily Struve (born Friedrich Georg Wilhelm Struve)”. Królestwo Polskie triangulation was aimed at joining Russian, Prussian and Austrian triangulations with similar works of Western Europe.