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
Encyclopædia Britannica encyclopedia, with fewer errors, Encyclopædia Britannica, Inc. in its detailed 20-page rebuttal called "Nature"'s study flawed and misleading and called for a "prompt" retraction. It noted that two of the articles in the study were taken from a "Britannica" yearbook and not the encyclopaedia, and another two were from "Compton's Encyclopedia" (called the "Britannica Student Encyclopedia" on the company's website). The rebuttal went on to mention that some of the articles presented to reviewers were combinations of several articles, and that other articles were merely excerpts but were penalized for factual omissions. The company also noted that several of what