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Jules Romains – Eyeless sight

The subject, when he turns in the direction of the source of light, for example towards a window opening on a fine clear sky, is suddenly enveloped in an absolute obscurity, and for several minutes he will have great difficulty in seeing anything at all paroptically.  I call this unexpected effect black dazzling.
A little later, if the subject remains in a sunlit place he is suddenly overcome by an impression of a confused, very intense, reddish light, which drowns all shapes and makes vision impossible.  This I called golden dazzling.
In the same way I have never succeeded in seeing, even confusedly, a source of artificial illumination – electric light, candle etc.  Moreover for artificial lights, at least those which are in ordinary use, the paroptic rendition is very bad.  In a room lit by a 50 candlepower light, the brightness perceived is not felt to be higher than that which there is in a room where only moonlight penetrates..........

Let us finally say a word on the shadow phenomenon. The experimenter is constantly struck by the sharpness and strength of the shadow his own body throws on neighbouring surfaces, in particular on walls.  If he lifts his [eye covering] and tries to estimate the same shadow, in the same optic conditions, with his eyes, he finds that it is much less clearly detached, that it forms on the wall a silhouette so indefinite that he would not think of noticing it.  The shadow of the body only becomes clear for the eyes towards dusk…I can find no exact explanation of this phenomenon.