First International Workshop on the History of Speech Communication Research (HSCR 2015)
The kymograph, one of the main devices used in early experimental phonetics, was quickly exploited to describe the sounds of languages in sub-Saharan Africa. By 1926, Doke used this device in its phonetics Zulu, to objectify the description of the main sounds of this language: vowels with epiglottal friction; the difference between aspirated and non-aspirated explosive consonants and consonants he describes as ejectives explosives; the three types alveolar laterals (voiced, voiceless and voiceless lateral); the duration of vowels and the different levels of tones. Doke shows that these are the plots of kymograph which to observe a similarity between the consonant bilabial implosive [ɓ] and clicks. The kymograph plots, presented in Figure 1 show indeed clearly a negative airflow at the release of the implosive and of the dental click contrasting with the positive flow observed after a bilabial explosive consonant.
Bibliographic reference. Demolin, Didier (2015): "The contribution of the kymograph to the description of african languages", In HSCR-2015, 71-76.