630,908. Building - blocks. BRYDON, N. M. March 11, 1947, No. 6844. [Class 87(i)] A channel-section building-block A having tapered flanges 2 is formed with longitudinal grooves 3 in its base 1 to facilitate severance into parts. The use of whole and part blocks in hollow walls and of whole blocks as facings for concrete floors and walls is described.