Gay-Lussac joined this man on an 1805-06 expedition to measure terrestrial 
Gay-Lussac joined this man on an 1805-06 expedition to measure terrestrial magnetism, and aided him in the discovery of the proportions of hydrogen and oxygen in water. He is known for his explorations of South America and his book Cosmos, an account of the relations between environment and flora and fauna.
Gay-Lussac joined this man on an 1805-06 expedition to measure terrestrial magnetism, and aided him in the discovery of the proportions of hydrogen and oxygen in water.
(Friedrich) Alexander Humboldt