industrial history, workers in a factory washing guncotton, artificial silk industry, germany, victorian 19th century, germany, 1890s - 化學人員 幅插畫檔、美工圖案、卡通及圖標歷史, 工廠, 19世紀風格
industrial history, workers in a factory spinning room for producing artificial silk from collodion, germany, victorian 19th century, germany, 1890s - 化學人員 幅插畫檔、美工圖案、卡通及圖標旋轉, 工業革命
19th-century metallurgy, roasting was a critical preliminary step in the smelting of sulfide ores (such as copper, lead, or zinc) - 化學人員 幅插畫檔、美工圖案、卡通及圖標雕刻圖像, 水管
industrial history, workers in a factory manufacturing guncotton, germany, victorian 19th century, germany, 1890s - 化學人員 幅插畫檔、美工圖案、卡通及圖標
industrial history, workers in a factory producing collodion for the artificial silk industry, germany, victorian 19th century, germany, 1890s - 化學人員 幅插畫檔、美工圖案、卡通及圖標工廠, 工業革命, 19世紀風格
