XXI. On the phenomena and laws of elliptic polarization, as exhibited in the action of metals upon light

Abstract

From the first dawn of the science of polarization, the action of metals upon light has presented a troublesome anomaly. Malus at first announced that they produced no effect whatever ; but by employing a different method of observation, I found that the light reflected by metallic surfaces was so far modified as to produce, when transmitted through thin crystallized plates, the complementary colours of polarized light. From a second series of expe­riments made previous to mine, Malus came to the conclusion, that the diffe­rence between transparent and metallic bodies consisted in this : that the former refract all the light which they polarize in one plane, and reflect all the light which they polarize in another; while metallic bodies reflect what they polarize in both planes. Having discovered the property of transparent bodies to polarize light by successive reflexions at angles at which a single reflexion produced no perceptible effect, I resolved to apply this method of examination to metals; and on the 7th of February 1815, when I first made the experiment, I discovered the curious property possessed by silver and gold of dividing a polarized ray into complementary colours by successive reflexions. As this subject promised to open a wide field of inquiry, I prepared for the ardent prosecution of it with all the metallic bodies which could be procured; but the pressure of professional business prevented me for about a month from doing any thing very effectual.