The presentation Of another book on retaining walls is made with the plea that it is essentially a text on the design and con struction Of retaining walls. The usual text on this subject places much emphasis upon the determination of the lateral thrust Of the retained earth; the design and construction Of the wall itself is subordinated to this analysis. Without gainsaying the importance Of the proper analysis Of the action Of earth masses, it is felt that such is properly Of secondary importance in comparison with the design Of the wall itself and the study Of the practical problems involved in its construction. It is the purpose Of the first chapter to present the existing theories Of lateral earth pressure and then to attempt to codify such theories evolving a simple, yet well-founded expression for the thrust. An attempt is made to continue this codification throughout the theories Of retaining wall design so that a direct and continu ous analysis may be made Of a wall from the preliminary selection Of the type to the finished section. Such mathematical work as is presented is given with this essential Object in view.