In flake industries most of the evidence for the production of controlled flakes lies in the waste rather than in the processes involved in the conversion into functional tools. Several approaches have been followed in Britain in the study of flake assemblages. S. HAZLEDINE WARREN (WARREN 1951) used measurements of angles of percussion and platform width, and contrasted results from assemblages dating from Clactonian to Mesolithic. A. BOHMERS demonstrated some techniques for recording and comparing breadthdength averages for microliths from different sites (BOHMERS and WOUTERS 1956). This approach most successfully adapted for waste flakes by ISOBEL SMITH in publishing the assemblages from Windmill Hill and West Kennett Avenue (SMITH 1965). Her work was followed by the few excavators who have published large assemblages in any detail.