Mechanical properties of the boundary lubrication layer

The two-term friction law is presented in a form following from its derivation on the basis of the effect of molecular forces close to the short- and long-range forces. This proves its heuristic significance. The boundary friction mechanism is described, in particular that applicable to the theory of sliding on ice. This theory was substantiated strictly quantitatively. In conclusion, the problem is formulated on the side of the transition from the viscous mode of a lubricating layer to the boundary lubrication mode.