[DeepL Translation - needs review] The "history of furigana" began when the Japanese language started using both kanji and kana! The two types of characters, ideograms and phonograms, and the two languages, Chinese and Japanese, are the "two 2s" that make up furigana. This long-awaited book, with newly written supplementary chapters, traces the history of furigana from the Heian period to the present day, and brings to light the diversity of the Japanese language.
(Translator: DeepL)
well written popular history of the uses of furigana
This is a popular history of the uses and development of furigana through history. The first chapter is introductory, where the author shows some modern furigana uses to get over the idea that they are not purely a "here is the reading of this kanji" device. After that the book works forwards through history, showcasing various historical texts and discussing how they use furigana and what this can tell us about the Japanese language at that time. The book includes images of the texts it discuss