The Chinese transcription of the École française d'Extrême-Orient (EFEO) was the most used phonetic transcription of Chinese in the French speaking world until the middle of the 20th century. It was created by Séraphin Couvreur of the aforesaid institute in 1902. It was superseded by Hanyu Pinyin.
Background
The transcription of the EFEO did not borrow its phonetics from the national official Standard Mandarin. Rather, it was synthesized independently to be a mean of Chinese dialects, and shows a state of sounds a little older in form (as in Latinxua Sinwenz and the older version of Wade-Giles). Hence, the phoneme [tɕ] (Pinyin: /j/), is transcribed as either /ts/ or /k/.
Since EFEO makes use, to a large extent, of the phonetic values of Latin letters as used in French, the transcription of many Chinese syllables into the EFEO system is quite similar to how they were transcribed by French missionaries in the late 17th to 19th centuries (e.g., as seen in Description ... de la Chine compiled by Jean-Baptiste Du Halde); for example, "Yanzhou Fou" is "Yen-tcheou-fou" in both cases. However, a few features (notably, the wide use of "ts", and the use apostrophes to show aspiration) distinguishes it from the early French missionary systems.