Breeze was small cinders and cinder-dust, essentially extinguished partially burned coal, used in burning bricks, and obtained from gasworks and coke ovens. The material (6–8 parts, in crushed form) was mixed with cement (1 part), cast in wooden moulds, and made into blocks for building walls or partitions not destined to carry heavy loads. A variant was the clinker-block, made from cement and clinker (mineral matter or ash from furnaces formed by the fusion of earthy impurities of coal, limestone, iron-ore, etc., also called slag). Breeze and clinker, because of their high sulphur content, proved to be unsuitable as aggregates for concrete as they caused rapid and extensive corrosion of steel-work, and spalling of the surface of the concrete.
W. McKay (1957)