History of the Encyclopædia Britannica the criteria by which the articles were sorted were not obvious even to scholars, despite Dr. Adler's claims that the sorting followed naturally from the "Propædia's" outline of all knowledge. In 1985, the "Britannica" responded to reader requests by restoring the index as a two-volume set. The number of topics indexed by the "Britannica" has fluctuated from 500,000 (1985, the same as in 1954) to 400,000 (1989,1991) to 700,000 in the current 2007 print version. Presumably, this recent increase reflects the introduction of efficient electronic indexing, since the size of the encyclopedia has remained nearly constant at approximately 40 million
Birds Britannica research period. Mabey's contribution was limited by his depression, leading to Cocker having a leading role, doing the bulk of the work and this more prominent credit. The Guardian described the book as "a glorious encyclopedia" and Cocker as "British bird life's perfect encyclopedist". The Times said "The entries for every species are a fascinating distillation of expert knowledge, personal account, reminiscence, literary reference and folk belief". Birds Britannica Birds Britannica is a book by Mark Cocker and Richard Mabey, about the birds of the United Kingdom, and a sister volume to Mabey's 1996 "Flora Britannica", about British plants. It