77/3005 Barraud, H.R. (1845-1896). (Portrait of John Tyndall). Woodbury type, 24,5x18 cm., laid down on orig. mount w. letterpress "W.&S. Ltd" in lower left corner and "Permanent" in lower right corner and w. the address "263, Oxford Street, London, & 92 Bold Street, Liverpool" in lower margin of mount.

- Lower margin of mount dam. (name of Barraud torn off).

= John Tyndall (1820-1893), Irish natural philosopher and scientist who was the first to discover the disturbing effect of too much carbon dioxide in combination with water vapour in the earth's atmosphere (the greenhouse effect).