Note 19 — Chapter IV · CONTEMPORARY DOCUMENTS.
Reading edition
[That is, at any single demagnetisation of the needle, it vibrates and emits the same tone as if it had been struck or mechanically caused to vibrate longitudinally.]—S. P. T.
Reading edition
[That is, at any single demagnetisation of the needle, it vibrates and emits the same tone as if it had been struck or mechanically caused to vibrate longitudinally.]—S. P. T.