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This result admits of an experimental test by means of the

photographic registration of stars during a total eclipse of the

sun. The only reason why we must wait for a total eclipse is

because at every other time the atmosphere is so strongly

illuminated by the light from the sun that the stars situated

near the sun's disc are invisible. The predicted effect can be

seen clearly from the accompanying diagram. If the sun (S) were

not present, a star which is practically infinitely distant would

be seen in the direction D1, as observed front the earth. But as

a consequence of the deflection of light from the star by the

sun, the star will be seen in the direction D2, i.e. at a

somewhat greater distance from the centre of the sun than

corresponds to its real position.

In practice, the question is tested in the following way. The

stars in the neighbourhood of the sun are photographed during a

solar eclipse.