Engraving depicting a Swan incandescent light globe and fitting, shown at the International Electric Exhibition at the Crystal Palace. Dated 19th...
Engraving depicting Swan incandescent light globes. The carbon filament here is of cotton threads hardened by soaking in sulphuric acid. Dated 19th...
Engraving depicting Edison's incandescent light globe in a pendant fitting. The filament here is of carbonized bamboo fibres. Dated 19th century.