7.34Extra for laying stone work in or under water and/or liquid mud including cost of pumping or bailing out water and removing slush etc. complete. NOTE :- The quantity will be calculated by multiplying the depth measured from sub-soil water level up to the centre of gravity of stone work under sub - water with the quantity of stone work in cum executed under the sub-soil water. The depth of centre of gravity shall be reckoned correct to 0.1 m, (0.05 m or more shall be taken as 0.1 m and less than 0.05 m ignored).