French economist Jean-Baptiste Say (1767-1832) was the first economist to hold a University Chaire in economics and he did his best to make economics a science and promote it as so. A follower of Smith, although critical of his ambiguities on value, he elaborated on the notion of utility and remains famous for his "Say’s law of markets", which is usually poorly understood and mischaracterized. Like Smith with his theory of the evolution of the division of labour, Say was trying to explain the positive link between markets and growth. He also remains famous for his theory of entreprenurship.
A Treatise on Political Economy, available from the LibertyFund Library of Economics and Liberty