Direct measurements of secondary currents at a river inflexion point
SECONDARY currents are defined as currents which occur in a plane normal to the local axis of primary flow. They may develop in pipes or open channels as a result of non-equal distribution of boundary shear stress or by skewing of cross-stream vorticity into a long stream direction1–3. Secondary currents distort the distributions of primary isovels and boundary shear stress from those found in simple flows and have important effects on sedimentary processes of erosion and deposition4,5. Direct measurements of secondary currents in river bends were reported recently6. Further data have been obtained for the reach around the inflexion point between bends (Fig. 1) and are reported here.
The formation of streamwise vorticity in turbulent flow
Mean streamwise vorticity in turbulent flow is shown to arise both from mean flow skewing and from the inhomogeneity of anisotropic wall turbulence. The structure of the Reynolds stress tensor is examined in several flows where the latter mechanism predominates. On the basis of a simple model for the anisotropy, the direction of the secondary currents is deduced for the corner boundary layer, the salient edge flow, and in the non-uniform nominally two-dimensional boundary layer.
AN INTRODUCTION T O THE SOILS OF THE SOUTH-EASTERN PORTION OF THE AUSTRALIAN ARID ZONE
Summary 
 
Seven soil regions, each of which is dominated by soils belonging to one or two great soil groups, are defined and mapped. The outstanding feature is the presence of a variety of soils with widely differing characteristics. The soils are deeper, have more profile differentiation and are finer-extured than those in most-arid regions and are frequently overlain by currently-forming deposits of wind-transported materials. Because the vegetative cover is better developed and there are only small areas of rocky hills and bare rock pediments, water erosion and deposition are not as prominent as in other arid areas.