Permalink Submitted by Chris Budd on August 14, 2019

This is a fair comment. However, if you look at not just one reflected wave, but the time that the wave arrives after several reflections, then it is possible to find where the whale is without measuring the depth directly. In fact you find the depth as part of the calculation. I will leave this calculation to the readers of Plus

## Finding the depth

This is a fair comment. However, if you look at not just one reflected wave, but the time that the wave arrives after several reflections, then it is possible to find where the whale is without measuring the depth directly. In fact you find the depth as part of the calculation. I will leave this calculation to the readers of Plus