London: The Royal Institution 1969. 377-470 pages. Tan wrappers printed in blue. Article "Vitamin B12" is found on page 377-396. Reading crease at spine, and minor soiling. Very Good. Wraps. 
Vol 42, Part VI, No. 199 of the Proceedings of the Royal Institution of Great Britain, containing accounts of the Friday evening discourses and other meetings.
Dorothy Crowfoot Hodgkin was awarded the Nobel Prize in Chemistry in 1964 "or her determinations by X-ray techniques of the structures of important biochemical substances." The present article provides some historical insight and a review of the properties of B12 with many illustrations. It also notes related exhibits in the Royal Institution library.
Other articles in this issue include Sir Lawrence Bragg on "What Makes a Scientist", Sebastian Z. De Ferranti on "Technology and Self-Determination", George Daniels on "The Astronomical Watch by George Margetts in the Possession of the Royal Institution, and some other Timekeepers of Margetts", and finally N. Kurti on "The Physicist in the Kitchen". An interesting issue!