Abstract
This paper has for its object to propose, refering chiefly to the model experimental studies of surface and totally immersed crafts, a new idea that probably enables us to presume the total resistance of a body by only measuring the total resistances of two models in arbitrary different scales, without any necessities to use the absolute values special to the body and the models except some special cases. Principal detailed investigations are made upon the items such as (a), when each model has the surface condition equal to that of the original and (b), when each model has the surface condition different from that of the original.
