Jean-Daniel Colladon

He received an Académie des Sciences award with his friend Charles Sturm for their measurement of the speed of sound and the breaking up of water jets.

Stymied by the lack of a sight of the water jet provided to the audience, he used a tube to collect and pipe sunlight to the lecture table.

Colladon reported this experiment to a wider audience in the Comptes rendus, the French Academy of Sciences' journal, in 1842.

Colladon won the Grand Prize of the Academy of Sciences in Paris for his research on the compressibility of liquids.

On December 25, 1844, Geneva was first illuminated by a network of gas lights, a project Colladon had been instrumental in advocating and promoting.

Colladon's "light pipe", as illustrated in an 1884 article