Thermodynamic measurements show that the nerves ' lipid membranes should show localized pulse units ("Soliptones"), which move concentrated without spreading, without changing shape and without losing strength. These pressure pulse devices (or sound pulse units) Form the basis for a new model of nerve impulses. This model can explain important thermodynamic properties of nerve pulses that are overlooked by the standard Hodgkin-Huxley model. Such a thermodynamic description is nerve pulses also provides a simple explanation of why the anesthetic's impression is proportional to the degree of solvent in the lipids.