This short note explains how the Bernoulli function, the total energy of a fluid, can be calculated from recent work on the thermodynamics of seawater. The Bernoulli function for an incompressible fluid has been used in the past to infer the absolute circulation of the ocean from hydrographic data alone. This is now both undesirable and unnecessary. Constructing the Bernoulli function for a hydrographic section also provides a rigorous procedure for calculating the total energy flux across the section, a quantity dominated by the ''heat flux''. ¿ American Geophysical Union 1995