Cannot help with correspondent’s study. CD has a poor ear for music. Recommends Helmholtz’s work.

Thanks for note and enclosure. Has written to [David?] Landsborough to say dried specimen was just what he wanted. Would like some more in spirits.

Very unwell.

Responds to correspondent’s request for information about shells from the Coquimbo beds in Chile. Difficulty in deciding on age of deposits and species. Notes views of Alcide d’Orbigny.

Thanks for offer of Helix for experiment. Asks for assistance. Mentions failure of his own experiment involving Helix pomatia.

Tells correspondent how to locate Michael Faraday’s widow [Sarah Barnard].