This week’s photograph is of St. Davids Cement Works, also known as the Queenston Cement Works, which was built near the Queenston Quarries by Isaac Usher and Sons in 1882. A layer of natural cement is located along the Niagara Escarpment. A thick layer was located near the Queenston Quarries, where the Cement Works was built to mine the product. Tunnels were dug into the cement to remove the material and install three to six kilns. The cement was then fired and packed into wooden barrels for sale. This natural cement was needed during the building of the Welland Canal as mortar between the large cut stone blocks. Unreliable as a building material it was eventually replaced by Portland Cement in the early 1900s. Portland had a more stable cement that set faster. The Cement Works closed in 1905.