Outer Probes

Some articles on probes, outer, probe:

Lens Clock - How It Works
... The lens clock has three pointed probes that make contact with the surface of the lens ... The outer two probes are fixed while the center one moves, retracting as the instrument is pressed down on the lens's surface ... As the probe retracts, the hand on the face of the dial turns by an amount proportional to the distance ...

Famous quotes containing the word outer:

    The use of natural history is to give us aid in supernatural history: the use of the outer creation, to give us language for the beings and changes of the inward creation.
    Ralph Waldo Emerson (1803–1882)