Bailard and Inman (1979) have raised a number of important questions in their study challenging the classic work of Bagnold (1954) on the flow behavior of granular materials. However, we believe that neither the theoretical arguments nor the experimental results of Bailard and Inman offer compelling reasons to reject Bagnold's basic conclusions. In the following remarks, we shall address several spects of Bailard and Inman's work, retaining their notation for ease of comparison. |