Book Review: Material Fluxes on the Surface of the Earth edited for the National Research Council, National Academy Press, Washington, 1994. No. of pages: xiv + 170, Price: £32.95. ISBN 0-309-04745-5; Book Review: Variability in Stream Erosion and Sediment Transport edited by L. J. Olive, R. J. Loughran and J. A. Kesby, International Association of Hydrological Sciences Publication No. 224, IAHS Press, Wallingford, 1994. No. of pages: x + 498. Price: £75.00. ISBN 0-947571-19-1