Cohesion pressure in liquid due to inward intermolecular force on surface molecules, not surface tension, causes minimization of liquid surface. Surface tension isn't what causes horizontal wire sliding on two limbs of a U-shaped wire to be in equilibrium in any position. Incorrectness of current relations for pressure differences between inside and outside of a bubble and one related to a solid drop is proven. In surface evaporation liquid increases the potential energy of its molecules by taking heat while their kinetic energies remain unchanged. Gas temperature decreases due to surface evaporation while some net heat is transferred from gas to liquid. So if gas temperature is only a little lower than liquid temperature, some net heat will be still transferred from gas to liquid due to surface evaporation and finally gas and liquid will be isothermal in a temperature lower than the initial temperature. This violates the 2nd law of thermodynamics. An equation is presented in case of its solving wave equation can be solved for general spreading of cylindrical wave. Using it, general spreading of cylindrical wave for large distances is obtained which consists of arbitrary functions.