Interlocking building block

In a building wall construction:

• a. a plurality of first building blocks each including upper and lower sides, front and rear sides and opposed ends,
• 1. said upper side including a longitudinal rib extending substantially between said ends said rib including laterally spaced first and second inclined faces and a transverse face extending therebetween, the intersection between said transverse face and said first inclined face defining an acute included angle and the intersection between said transverse face and said second inclined face defining an obtuse included angle.
• 2. said lower side including a longitudinal groove extending substantially between said ends, said groove including laterally spaced first and second inclined faces and a transverse face extending therebetween, the intersection between said transverse face and said first inclined face defining an acute included angle and the intersection between said transverse face and said second inclined face defining an obtuse included angle, said groove receiving the rib of a compatible block in interfitting relation,
• b. a plurality of second building blocks each including upper and lower sides, front and rear sides and opposed ends,
• 1. said upper side including a longitudinal rib extending substantially from one of said ends to a point midway between said ends said rib including laterally spaced first and second inclined faces and a transverse face extending therebetween the intersection between said transverse face and said first inclined face defining an acute included angle and the intersection between said transverse face and said second inclined face defining an obtuse included angle,
• 2. said lower side including a longitudinal groove extending substantially between said ends including laterally spaced first and second inclined faces and a transverse face extending therebetween the intersection between said transverse face and said first inclined face defining an acute included angle and the intersection between said transverse face and said second inclined face defining an obtuse included angle, said groove receiving the rib of a compatible block in interfitting relation, and
• c. a plurality of third ribless and grooveless building blocks each having a length substantially equal to twice the width thereof,
• d. said first, second and third building blocks being laid in first and second tiers,
• 1. the first tier including a plurality of blocks disposed in perpendicularly related rows one of said rows including a plurality of endwise related first blocks, an endwise related second block and terminating with a transversely related third block defining the wall corner, and the other of said rows including a plurality of endwise related first blocks abuting said second and third blocks,
• 2. the second tier including a plurality of perpendicularly related rows one of said rows including a plurality of endwise related first blocks, an endwise related second block and terminating with a transversely related third block defining the wall corner, and the other of said rows including a plurality of endwise related first blocks abuting said second and third blocks,
• 3. said other row of said second tier overlying said one row of said first tier, and said other row of said first tier being overlain by said one row of said second tier.