They were originally photographed in 1976 on the Galapagos Rift between 2400-3700m depth.

Yet striking a balance between depth and accessibility has been challenging.

The play between surface and depth is appealing, in part because it seems so ripe for further complication and development (Johnson).

But the best works bounce the viewer back and forth between surface and depth.

Studies show that a strong correlation between financial depth and long-term economic growth and poverty reduction.

Naturally, trade-offs between breadth and depth were necessary.

"The wine gestalt is an interplay between surface and depth," he said.

His behavior varied between depth and shallowness, brazenness and withdrawal.

Power-law relationships between channel slope, depth, and width are given as a function of discharge by "river regime".

Others argue that a proper balance between numerical growth and depth of spiritual growth is needed.