In a previously published statement (P arr 1937, b) the writer has listed the main reasons why, in the present state-of our knowledge of the actual as distinct from the ideal dynamics of ocean currents, he feels inclined to take greater confidence in the evidence of the actual paths of flow obtained from a study of the identifying properties of the water masses, than in the conclusions reached by present efforts to deduce the trajectories of motion from hydrodynamic calculations and considerations. In this article a further elaboration and elucidation of these objections against the unrestricted use of dynamic methods for the determination of ocean current trajectories will be attempted, while suggestion for obtaining a presumably closer approach to an accurate presentation of flow through isopycnic analysis by means of identifying properties will be presented in the next article in this issue.