Engraving depicting the use of a magnesium photographic flash light
Engraving depicting the use of a magnesium photographic flash light devised by attaching a rubber tube to the mouthpiece of a clay pipe, filling the bowl with magnesium and wrapping bowl with alcohol-impregnated cotton wadding. When the subject posed and was in focus the cotton was ignited and the tubing blown through to give a good flame. Dated 19th century