Extract, 'On the action of the rays of the spectrum on vegetable juices' from a letter from Mrs M [Mary?] Somerville to Sir J F W [John Frederick William] Herschel Subject: Physics Published in Philosophical Transactions as 'On the action of the rays of the spectrum on vegetable juices. Extract of a letter from Mrs. M. Somerville to Sir J. F. W. Herschel, Bart., dated Rome, September 20, 1845. Communicated by Sir J. Herschel'. Written by Somerville in Rome [Italy]. Communicated by Herschel. Received by the Royal Society on 6 November 1845. Read 27 November 1845. Abstract published in Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society of London], Volume 5, 1851. 20 September 1845