1. The results presented characterize the fundamental difference of stresses in the base under a round and an extended (rectangular) foundation: increased stresses under the ends and edges of a rectangular foundation, greater compression of the soil layers under the round foundation, difference in the ratios of the principal stresses in the base of round and rectangular foundations, etc. 2. In the case of an average contact pressure less than half of the ultimate with respect to stability, the settlements of a rectangular foundation on sand are equal to or slightly less than the settlements of a round foundation of the same area.