Philosophers in ancient Greece were the first to use the term "atom" to describe the smallest possible bit of matter. They hypothesized that all things were made up of atoms, and could be theoretically broken down into atoms. The atom, however, was indestructible. Study of atomic theory proceeded slowly. Experimental scientists of the 16th and 17th centuries developed methods of analyzing gases, liquids, and solids to determine the individual elements of which they were composed. The founder of modern atomic theory was British chemist John Dalton. Dalton's experiments explained how atoms link together to form molecules. He also explained the nature of these chemical bonds, and performed a number of experiments concerning the formation of various chemical compounds.