The current study, which is an interface between Chinese linguistics and Japanese linguistics, will inquire into the sounds of Chinese characters in Japanese from the viewpoint of historical linguistics. After Chapters 2 and 3 prepare the readers, Chapter 4 will review how scholars of Japan have studied Sino-Japanese. So far, Tsukishima (1993) is virtually the only case in English to deal with the history of studies in Sino-Japanese. The review will mention what kinds of problems underlie past studies in Sino-Japanese. Chapter 7 will make suggestions for future studies in Sino-Japanese. The rhyme table titled the Yunjing (Inkyo in Japanese) has traditionally been the main focus of the studies in Sino-Japanese to pursue how Sino-Japanese should have sounded from a prescriptive viewpoint but not how Sino-Japanese actually sounded from a descriptive viewpoint. Even though scholars of Japan, even after switching from prescriptivsm to descriptivsm, have extensively carried out inquiries into Sino-Japanese in relation to Ancient Chinese (or Middle Chinese), scholars have carried out virtually no inquiry into Sino-Japanese in relation to Archaic Chinese (or Old Chinese). By definition, a "kun"-reading (Japanese reading) and an "on"-reading (Chinese reading) of a Chinese character in Japanese are supposed to have separate sources. Karlgren (1926) lists Chinese characters, the "kun"-readings of which might be derived from Archaic Chinese and therefore predate the "on"-readings. However, Kamei (1954) virtually refutes them. Chapter 6 will examine more than 150 examples of Chinese characters the "kun"-readings of which resemble their counterparts in Archaic Chinese. The examination will first attempt the derivation of each example and will then rule out the possibility of the "Goon," the "Kan'on" and the "Toon" with the phonological correspondence rules, which will be established in Chapter 5, for each example in order to indicate the possibility of its deriving from Archaic Chinese. They, deriving from Archaic Chinese, might be called Old Sino-Japanese as opposed to what is now called Sino-Japanese, deriving from Ancient Chinese at the earliest. Since linguistics alone might be unable to solve the present problem, Chapter 7 will suggest a multidisciplinary approach, including social sciences and natural sciences. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]