11.   They were able to study the area at different depths, especially earthquakes that had occurred at those depths.

12.   To teach himself how, he photographed a white cup and saucer a thousand times, against backgrounds of different tonal depths, making notes on each exposure.

13.   In the next canyon, a different depth delivers a shade of brilliant blue.

14.   The defused mines are buried at different depths, in either dirt or sand, to test different conditions.