Als to Thomas Hawkins from Faraday in reply to his letter giving results of an experiment using an iron plate in dilute nitric acid to create a battery. Faraday offers his comments on his results. Dated from Royal Institution and addressed to Thomas Hawkins at 13 Kings Road Brighton. With pencil comments on the letter by Thomas Hawkins, explaining that later results by Mr Groves and Schonbein made him give up his research on this particular type of battery.