when was the earliest use we know about for concrete
Roman concrete It is uncertain when Roman concrete was developed, but it was clearly in widespread and customary use from about 150 BC; some scholars believe it was developed a century before that.[3]
Hockey puck Ice hockey and its various precursor games utilized balls until the late 19th century. By the 1870s, flat pucks were made of wood as well as rubber. At first, pucks were square. The first recorded organized game of ice hockey used a wooden puck, to prevent it from leaving the rink of play.[1] Rubber pucks were first made by slicing a rubber ball, then trimming the disc square. The Victoria Hockey Club of Montreal is credited with making and using the first round pucks, in the 1880s.[2]