The electrode of a manipulator cuts tissue. The scalpel has rectifying circuit for supplying a rectified voltage to a radio frequency circuit which produces an output current signal at a substantially constant frequency to the electrode. The radio frequency circuit has an electronic switch controlled by an oscillator and pilot circuit. According to the method a wave form is applied to the electrode having such a power that the energy transferred to the manipulator is substantially equal to the sum of the energies required to break the bonds of the molecules of the tissue to be cut. The invention relates also to the electronic scalpel carrying out said method.