ABSTRACT
ART. 8.1. INTRODUCTION I t is everyday knowledge that sound rock, evenly bedded, will stand with a sheer face to considerable heights. This can be seen in artificial form in deep railway cuttings; and there are countless examples in nature - the cliffs of Beachy Head to mention only one. Soils on the other hand cannot stand more steeply than their natural angle of repose, as evidenced again in railway work where engineers have cut back to slopes ranging from about 1 in 1| to 1 in 3 depending on the nature of the soil, and other physical con ditions. Where there are practical objections to sloping back in this manner (as for example at basements to city-buildings or where industrial materials like sand and stone have to be stored in limited areas), a wall has to be built to retain all material required to lie above the natural angle of repose.
