Mathew Carey Lea (August 18, 1823 – March 15, 1897) was an American chemist known for his research on the chemical and physical properties of silver halide salts and their usage in photography.

[3] Lea received a classical education including the trivium (grammar, logic and rhetoric), quadrivium (arithmetic, geometry, music and celestial navigation).

Elizabeth had earlier married merchant William Bakewell, but Blakewell had died in Cincinnati in 1850, leaving her with a young daughter.

[7] Lea became interested in photography and in 1840, created a series of images of his father's plant and shells collection that was displayed at the American Philosophical Society.

[2] Lea read the law under the tutelage of prominent attorney William M. Meredith, and in 1847 was admitted to the Pennsylvania Bar.

[9] However, Lea was sickly, and left the practice of law to travel to Europe and other places for his health, as well as to pursue his scientific avocation.

[17] Due to the loss of an eye during an experiment with picric acid, and his constantly ill condition, Lea spent most of his time in solitude.