A plastic lens is described which will bend light rays parallel to the lens axis in the same way as a static (Schwarzschild) gravitational field. This allows one to observe the optical distortions caused by a (nonrotating) black hole directly. The double‐imaging property is discussed with particular application to the recently announced double quasar which is suspected to be a gravitational double image of a single quasar. A detailed cosmological model calculation is performed in order to place limits on the mass of the galaxy acting as the lens. It is seen that if the double quasar is a double image and if the lens is a massive galaxy then we will have established that the quasar redshift is cosmological rather than gravitational. The gravitational lens thus occupies a key role in resolving this question.

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