Aristotle stated "everything was made up of earth, air, fire, and water." Aristotle was well known and greatly respected among people so his hypothesis was preferred over Democrtius'.
Democritus stated "each type of matter was made up of a different type of atomos." Atomos mean "indivisible." Democritus proposed this word to portray the smallest particles that could not be broken down further.
The Middles Easterns learned how to change a range of substances to their advantages. They applied simple stone tools; which eventually lead to the production of glass and creamic materials.
In the 1660's, Robert Boyle experimented with the behavior of gases. He determined the composition of gases. He also explored with gases under pressure.Boyle had also believed Democritus' theory that matter was made up of tiny particles. He strongly believed that the tiny particles in matter would group together to form individual substances.
1700's and 1780's Antoine Laurent Lavoisier studied how chemicals interacted with each other, chemical interactions. Later on he developed a system for naming chemicals, this made it easier for scientists to compare the results of their experiments. Because of his great works he is called the "father of modern chemistry"
In 1808, John Dalton developed the theory of the composition of matter. He also announced that matter is made up of elements. Dalton was the first to define an element as a pure substance that contained no other substances. He stated "each element is composed of a particle called an atom." John discovered the Theory of Atomic Structure. His basic description was correct but some of his ideas were later altered.
1913 Niels Bohr conceived the theory of an atom. He stated that they move in specific circular orbits, or electron shells, he believed that electrons jump between these shells by gaining or losing energy.
2011 Sarah Dupont, my understanding of the structure of matter is that, "I believe all matter is made up of different combinations of atoms".
In 2012, James Chadwick said that a positively charged nucleus was surrounded by a cloud of electrons.