This paper deals the experimental results of acoustical articulation of the speech sounds in the open air. Two years ago I reported the effect of?the line, length upon the telephone speech articulation. In this experiment the front articulation and the back articulation are considered, respecting the speech-mouth as center The articulation losses in these two cases are experimented and plotted as characteristic curves. The drop of consonants is remarkable phenomenon also. The percentage of drop is proportional to the distance.
In the experiment many precautions are taken. The following conditions are necessary: flat, wide and noiseless place. No wind the test must be simple, without tire. The place was chosen at the riverside, Futago-tamagawa. The experiment was done during four days. The effect of wind is negligible, and the direction of wind to the speech-mouth was maintained constant always.
