Hippolytus

“ For a sufficiently long time after the descent of the axe, the sound of the stroke is heard, so that it takes a longer time to reach the listener. And for this reason, therefore, it is not possible for the Chaldeans accurately to take the time of the rising zodiacal sign, and consequently the time when one can make the horoscope with truth. And not only does more time seem to elapse after parturition, when he who is sitting beside the woman in labour strikes the metallic plate, and next after the sound reaches the listener, that is, the person who has gone up to the elevated position ”

“ However, grant that the birth is comprehensible, yet neither is it possible to signify this at the exact time; for as the noise of the metallic plate is capable of being divided by a longer time and one protracted, in reference to perception, it happens that the sound is carried to the height (with proportionate delay) . And the following proof may be observed in the case of those felling timber at a distance. ”