For this new edition the system of increments of gradient have been modified to reduce the need for interpolation, now matching that of (Tables D). Continued from the Seventh edition are the results of new work on the assessment of roughness size in commercial pipes manufactured from materials currently utilised to give a smooth finish and on the assessment of additional losses at bends in such pipes.
Volume 2 uses a newer, alternative, route to support the application of the unit size method. For this route, Manning equation tables (Tables D) act also as a carrier for obtaining solution of the Colebrook-White Equation when combined with (Tables E). For Volume II of the Seventh edition, the Manning equation tables were redone reducing the increment in gradient between entries to ease interpolation. This is continued here. As before the coverage of discharges continues into the order of scale of continental rivers. In Volume II a wide range of conduit and channel shapes is covered by tables of properties based on unit size, with key examples of these tables also included in Volume I. This gives illustration of solutions supported by the established form of Colebrook-White tables, as is possible for most conduits and smaller channels when the two volumes are used in conjunction.
In both volumes the tables of unit properties provide aid for both gradually varied and rapidly varied flow problems. Also, there is more detailed coverage of the possible effects of variation in water temperature within the normal water resources and drainage range of temperatures. Both volumes include a revised treatment of part-full flow in circular pipes and of the assessment of the effect of conduit shape on free-surface flow in general.