Joseph Louis Gay-Lussac was a French chemist noted for his original investigations into the behavior of gases. In 1808, Gay-Lussac deduced that gases at a constant temperature and pressure combine in very simple numerical proportions by volume, resulting in a product or products; gases also bear a simple proportion by volume to the volumes of the reactants. He also investigated compounds found in plants and animals that contained just carbon, hydrogen, and oxygen, including the compound formed by plants during photosynthesis. He found that the ratio of hydrogen to oxygen in the mystery compound was the same as that of water. This indicated to him that the compound was essentially a combination of carbon and water. For this reason he named the organic compound produced by plants carbohydrate, which means, "watered carbon." Gay-Lussac’s work is considered to be the earliest important work on the process of photosynthesis.