In 1886, Lippmann's interest turned to a method of fixing the colours of the solar spectrum on a photographic plate. On 2 February 1891, he announced to the Academy of Sciences: "I have succeeded in obtaining the image of the spectrum with its colours on a photographic plate whereby the image remains fixed and can remain in daylight without deterioration." By April 1892, he was able to report that he had succeeded in producing colour images of a stained glass window, a group of flags, a bowl of oranges topped by a red poppy and a multicoloured parrot. He presented his theory of colour photography using the interference method in two papers to the Academy, one in 1894, the other in 1906.