Marshmallow, Althaea officinalis. Handcoloured botanical illustration drawn and engraved on steel by William Clark from John Stephenson and James Morss Churchill's "Medical Botany: or Illustrations and descriptions of the medicinal plants of the London, Edinburgh, and Dublin pharmacopias," John Churchill, London, 1831. William Clark was former draughtsman to the London Horticultural Society and illustrated many botanical books in the 1820s and 1830s.