Abstract: | In a previous publication (Allison, 1989), a non-destructive method for indirectly determining rock strength by measuring Dynamic Young's Modulus was described. Data were presented to assess the Grindosonic apparatus in relation to standard laboratory techniques. A further Short Communication (Allison, 1990) evaluated the non-destructive test as a field technique, in part achieved by comparing the Grindosonic results with data collected using the Schmidt hammer. The Schmidt hammer is a widely used field technique in geomorphology for determining rock strength (see for example Day and Goudie, 1977; Day, 1981). Allison (1989, 1990) also suggested that the elastic properties of materials are becoming increasingly important in geomorphological studies. The opportunity to provide additional information and comments here is appreciated. |