2016-02-022016-02-02after 1870after 1870http://hdl.handle.net/10222/19714Two "Ideal"furnaces manufactured by "Thos. Robertson & Co,"displayed inside a building. Furnaces also show: "Patented May 9, 1905"1 photograph : b&w glass photonegative ; 21 x 26 cmequipmentImage