Abstract: A modular system of bottles having a predetermined neck configuration and indentations in the bottom and side walls to receive the end of a neck of an abutting bottle to automatically center and space the bottles apart by a distance corresponding to that of a mortar joint. The bottles can be made in full, half, one-quarter, and double sizes, and may include one-third and two-third sizes, etc. The bottles can be laid up into a wall with the mortar joint falling either at the half point, or at the third point.