Pinned to it was a little concave mirror, for making triumphant signal flashes from the summit.

It illuminates a smaller area on the concave mirror, leading to a small beam-width on the way to the flat mirror.

He later modified the theory to simply involve a concave mirror and a comparator mirror.

This involved creating a set up which observed how the position of a concave mirror would affect the real object that it reflected.

He often painted with the aid of a concave mirror, and to obtain exactness looked at his subject through a frame crossed with squares of silk thread.

It also made effective aesthetic use of the concave shape of the coin's obverse.

Calculations are further complicated by the effects of shadowing and thermal reillumination, whether caused by local craters or a possible overall concave shape.

The male can be identified by the slightly concave shape to its plastron.

In addition, the females' plastrons are much flatter than those of the males, which have a concave shape.

Eventually, as the cord continues to unwind, the surface of the water assumes a concave shape as it acquires the motion of the bucket spinning relative to the experimenter.