AbstractThe study of the effect of several variables affecting the determination of E-modulus by flexure was undertaken in order to remove the inadequacy of the testing procedure, and to gain a more intimate knowledge of their significance. The diameter, span-depth ratio, heat treatment, porosity, bulk density etc. affect the values of E-modulus considerably. The span-depth ratio is an important factor and should be between 20 and 25 to 1 for such determinations. E-modulus of kaolin, sillimanite, alumina, and zircon have been obtained by such flexural methods and they compare favourably when due consideration is paid to the variables studied in this investigation.