mortarless interlocking blocks for making a wall assembly composed of masonry blocks laid up in multiple courses and consisting of stretcher blocks making up longitudinal walls which converge at the corners in corner blocks which are formed as right hand and left hand corner blocks . the blocks in the wall assembly are made with a unique arrangement of mating ribs and grooves which makes the laying of the blocks easy and yields a cooperating group of blocks which can carry loads and which makes the creation of a wall very simple and fast as no mortar is needed and the blocks are self aligning and stable .