fig5 the weight of the structure will in reality increase when liquid is removed and replaced by water and contributes to the penetration of the structure down into the sea bottom when the desired penetration depth of the skirts 14 has been reached the removal of the remaining liquid is discontinued by closing off a valve 16 on the top side of the fundament whereafter the tube or tubes 8 and 9 may be removed and whereafter the fundament is ready to be used in accordance with the task involved as a rule all liquid is withdrawn and additional penetration is achieved by pumping the water out of the fundament the principles in accordance with the invention may be realized with various types of fundaments as long as these fulfill the necessary requirements fig6 8 illustrate one practical embodiment for a fundament structure including necessary auxiliary equipment and in which figures the same reference numbers in all figures designate the same parts the number 20 designates a fundament structure especially adapted to be used with the method in accordance with the invention the fundament comprises here two mutually spaced integral parts or sections 22 and 24 and a relatively small center chamber 23 arranged therebetween having a known height and volume the center chamber 23 has a closed top and is open downwards the size of this center chamber is in the figures enlarged for.