Here are five rectangular plate-beams of infinite length resting horizontally on the five elastic foundations upon the semi-infinite rigid base. The author has investigated the defiections， defiection-angles， bending moments， shearing forces， and reactional pressures of these five plate-beams. By applying the end-conditioning forces to these infinite plate-beams， one could get the stresses of the five rectangular plate-beams of the limited length. As a matter of the design-problems, if one could put a few rectangular plate-beams horizontally into the body of an earth dam，then by the function of these plate-beams，the infilitration curves of the reservoir water would be disturbed，and the earth dam might be saturated in the mere neighbourhood of the upstream face of the dam, and consequently its body might be comparatively stabilized. As to the applications of the principles and the design-problems may be treated in after days
