Abstract: There is provided a masonwork which consists of stacked building blocks forming several superimposed horizontal courses. The upper sides of blocks in lower courses and the undersides of blocks in the next-higher courses have registering mirror symmetrical sockets in the form of generally hemispherical cavities for reception of spherical connectors. Auxiliary connectors can be provided to couple neighboring blocks of each course to each other; such auxiliary connectors constitute discrete parts having webs received in aligned channels of the respective blocks and end portions which extend into neighboring sockets or blind bores of such blocks.