In this report, under one assumption the author proposes an equation for the wave-making resistance of the ship forms in three dimensions. One of the characteristics of the equation is that we can use the diagrams prepared in the Report No.3 and then a direct calculation without searching for the velocity potential will be possible.
And by this method he examines systematically in ditail the effects of principal dimensions of ships, coefficients of fineness, height of the center of gravity, load conditions, and rolling period etc. upon the resistance, mainly for cargo ship-forms and fishing-boat-forms.
Now this study, the author supposes, comes to a close and the summary of the study is appended at the end of this report.