According to the linear transport theory, the mobile cation flux, , in an electronic conductor oxide, e.g., , is given as , being the transport coefficient and the electrochemical potential gradient of charge carriers of type . It has, however, been normally presumed that without experimental verification. By an electrochemical means we have measured the “charge of transport” of the cation, , in the ranges of temperature and oxygen partial pressure, and , respectively, and found, contrary to the normal presumption, that takes a value in a range of 0.7 to 1.6. Furthermore, it tends to increase with decreasing temperature and increasing oxygen partial pressure. The principle and details of the electrochemical experiment employed are given and the compilation is made of all the data on of which have been made available via various means up until now.