An expert on your field

An expert in my field that I admire is John Dalton, the british chemist and physicist. 

Dalton was born in a humble family, and when he had twelve years old he began to teach in a school in his hometown. He don't have a really good education due to the lack of money of his family, but his inexhaustible curiosity and eagerness of knowledge allowed him to go far.

Among the things that he researched is the daltonism, a visual illness that suffered, and the most important of all Dalton's investigations, the atomic theory.

To sum up, the main points of Dalton's atomic theory are:

1. Elements are made of extremely small particles called atoms.
2. Atoms of a given element are identical in size, mass and other properties; atoms of different elements differ in size, mass and other properties.
3. Atoms cannot be subdivided, created or destroyed.
4. Atoms of different elements combine in simple whole-number ratios to form chemical compounds
5. In chemical reactions, atoms are combined, separated or rearranged.

John Dalton

I like Dalton for the great contribution of his theory to the chemistry, and the fact that he developed it as a result of his studies of the gases (yes, he also studied the gases and he proposed a law called Dalton's Law).