Baxter's transcription for Middle Chinese

William H. Baxter created a special way to write the sounds of Middle Chinese using letters. This system helps scholars study old Chinese texts by showing how words sounded a long time ago. Instead of guessing the exact sounds, Baxter’s method gives clues from medieval sources. It acts as a helpful starting point for understanding even older Chinese sounds, known as Old Chinese phonology. This transcription makes it easier for people to compare and discuss ancient Chinese words and their meanings.

Sources for Middle Chinese

Further information: Rime dictionary and Rime table

The main source for studying old Chinese sounds is the Qieyun, a rime dictionary made by Lu Fayan in 601 CE. It helped people read classic books correctly by dividing words into groups based on their sounds and tones. Each sound group was shown using two common words that hinted at the beginning and end sounds of the syllable.

Later, the Guangyun expanded on the Qieyun, adding more sound groups but keeping the same system. Since the original Qieyun was lost for a long time, most research used the Guangyun. During the Qing dynasty, a scholar named Chen Li studied the Guangyun to understand the basic sounds used.

During the Song dynasty, scholars made rime tables that organized the sounds in a smart way. They grouped the beginning sounds by where and how they were made, and the ending sounds into 16 groups. Inside each group, sounds were sorted by whether the mouth was open or closed, their tone, and their "division". Some ending sounds always appeared in certain rows of the tables and were named based on their division. Division III sounds could be split into three types based on where they appeared in the tables.

Baxter's notation

Many scholars have tried to describe the sounds of Early Middle Chinese, a system recorded in old books. These descriptions often use letters to show sounds, but they can be hard to understand and many people debate them.

To help study older Chinese sounds, William H. Baxter created a special way to write these sounds using letters. This method does not guess what the real sounds were, but instead uses information from old books. It is simpler than older methods but keeps important details about how sounds were made.

Notes:

• -r-, -y- and -h- show special ways sounds were made, not separate sounds.
• The sound h- is a soft hissing sound while x- is a harder hissing sound.
• The old sound 云 is treated the same as h- in Baxter's system when it comes before certain endings.

The sound -j- is left out after certain sounds that end in -y-.

Finals ending in nasals -m, -n and -ng could occur in various tones, with similar endings in -p, -t and -k placed in another tone.

In a newer book, the endings -ɛɨ and -wɛɨ are written as -ea and -wea.

The vowels æ, ɛ and ɨ are written as ⟨ae⟩, ⟨ea⟩ and ⟨+⟩ in a simpler version of Baxter's system.

The rising tone is shown with a trailing X, and the departing tone with a trailing H. The level and entering tones have no special mark.