By the way, before leaving this subject, I would like to add a few comments.
在结束这个问题之前顺便一提,我希望能再提出一些看法。
but that was precisely the idea adopted in some of the early instruments (seismometers) for recording earthquake waves.
但是早期记录地震波的仪器(测震仪)正是采用了这种思路。