Notable Scots: Innovation & Discovery

Thomas Graham (1805-1869):

Chemist

John Graham

This scientist was born in Glasgow and studied chemistry at the university in that city. In 1833 he discovered that the rate of effusion of a gas is inversely proportional to the square root of its molecular weight. "Graham's Law," as it came to be called, laid the basis for separating isotopes by diffusion; later this practice was developed into the kinetic theory of gases.

Graham is also credited as the founder of colloidal chemistry. Colloids are a chemical mixture of one substance evenly dispersed through another substance. The process Graham developed to separate colloidal solutions from electrolytes - dialysis - is still used today in modern medicine to artificially replace lost kidney function caused by renal failure.