Patent ID: 7806038

Claim:
Building blocks, each comprising: a top surface; a bottom surface; first and second side surfaces; first and second end surfaces; wherein one of the first and second side surfaces is tapered outward from the first and second end surfaces only and the other of the first and second side surfaces is tapered inward from the first and second end surfaces only; wherein one of the first and second end surfaces is tapered outward from the first and second side surfaces only and the other of the first and second end surfaces is tapered inward from the first and second side surfaces only; wherein one of the top and bottom surfaces is tapered outward from the first and second end surfaces and the first and second side surfaces and the other one of the top and bottom surfaces is tapered inward from the first and second end surfaces and the first and second side surfaces; wherein the inwardly tapered surfaces are complimentary to the outwardly tapered surfaces of laterally and vertically adjacent like building blocks; a vertical projection extending from the top surface; a recess in the bottom surface, wherein the recess is complimentary to and positioned to receive the vertical projection of a vertically adjacent like building block when the blocks are moved vertically into top-to-bottom relationship with each other; a vertically elongated first male locking member projecting from one of the side surfaces and having a generally T-shaped cross-section; a vertically elongated first female locking slot formed along the other one of the side surfaces and being sized and configured to receive and lock with the male locking member on a side surface of a like building block when the blocks are moved vertically into side-by-side relationship with each other; a vertically elongated second male locking member projecting from one of the end surfaces and having a generally T-shaped cross-section; and a vertically elongated second locking slot formed along the other one of the end surfaces and being sized and configured to receive and lock with the male locking member on an end surface of a like building block when the blocks are moved vertically into end-to-end relationship with each other; the building blocks, when interlocked side-by-side and top-to-bottom, forming a wall having no vertical joint extending through the wall from one side of the wall to the opposite side of the wall.