How and Why Library (1913) This was a supplement to the above that, in 1934, was acquired by another company and spun off into a new work. Later incorporated into Childcraft.
Anglo-American Encyclopedia and Dictionary (1902) - an unauthorized reprint of portions of the Encyclopedia Britannica with an unrelated dictionary attached. (Link includes vols. 2-4, 6-9, 11-12)
Twelfth edition (1922) a 3-volume supplement to the eleventh edition was released that summarized the developments just before, during and after World War I; these three volumes, taken together with the eleventh edition of 1910, became known as the twelfth edition.
Thirteenth edition (1926) three new volumes covering the history of 1910–1926, which were intended to supplant those of the twelfth edition. Again taken together with the eleventh edition, the new volumes became known as the thirteenth edition.
Fourteenth edition (1929) after this the Britannica began a policy of continuous revision.
10 Eventful Years (1947) a special supplement on 1937-1947 - the
Second World War, as well as the years immediately preceding it and following it.
Fifteenth edition, first version, other wise known as the New Encyclopædia Britannica (1974) this began the change of format into Propædia, Micropædia, and Macropædia, as well as eschewing an index.
Fifteenth edition, second version (1985) restored the index as a two volume supplement, streamlined the three type format for easier use.
How and Why Library (1913) This was a supplement to the above that, in 1934, was acquired by another company and spun off into a new work. Later incorporated into Childcraft.
Anglo-American Encyclopedia and Dictionary (1902) - an unauthorized reprint of portions of the Encyclopedia Britannica with an unrelated dictionary attached. (Link includes vols. 2-4, 6-9, 11-12)
Twelfth edition (1922) a 3-volume supplement to the eleventh edition was released that summarized the developments just before, during and after World War I; these three volumes, taken together with the eleventh edition of 1910, became known as the twelfth edition.
Thirteenth edition (1926) three new volumes covering the history of 1910–1926, which were intended to supplant those of the twelfth edition. Again taken together with the eleventh edition, the new volumes became known as the thirteenth edition.
Fourteenth edition (1929) after this the Britannica began a policy of continuous revision.
10 Eventful Years (1947) a special supplement on 1937-1947 - the
Second World War, as well as the years immediately preceding it and following it.
Fifteenth edition, first version, other wise known as the New Encyclopædia Britannica (1974) this began the change of format into Propædia, Micropædia, and Macropædia, as well as eschewing an index.
Fifteenth edition, second version (1985) restored the index as a two volume supplement, streamlined the three type format for easier use.