Eminent Irish American mathematician Eugenius Nulty tutored both Carey and his younger brotherHenry Charles Lea at their Philadelphia home. The erudite Nulty gave the Lea brothers a classical education and singlehandedly taught the pair the entirety of the trivium and quadrivium as well as classical languages and history. Nulty immersed the boys in a single subject for long periods to encourage its complete mastery. During their years under Nulty's tutelage, Henry and Carey also received instruction in the Booth & Boy private chemical laboratory.
Marriage
In 1852, Matthew Carey Lea married Elizabeth Jaudon, sister of Henry Charles Lea's wife. Elizabeth had earlier married merchant William Bakewell, but Blakewell had died in Cincinnati in 1850, leaving her with a young daughter. The couple had a son, George Henry Lea, who helped in the family publishing business. After Elizabeth's death, Carey Lea married Eva Lovering, daughter of Harvard Professor Joseph Lovering, but they had no children.
Career
Carey Lea read the law under the tutelage of prominent attorney William M. Meredith, and in 1847 was admitted to the Pennsylvania Bar. The highly successful family publishing firm published some legal books. However, Carey Lea was always sickly, and traveled to Europe and other places for his health, as well as to pursue his scientific avocation. Carey Lea worked in the laboratory of Professor James C. Booth, and constructed a laboratory in his home in Philadelphia's Chestnut Hill neighborhood. In 1841, the American Journal of Science and Arts published his first paper at his father's request, On the First or Southern Coal Field of Pennsylvania and that publisher would ultimately publish approximately 100 more. In July 1864, he published two papers concerning aspects of platinum. In his later years, Carey Lea devoted himself chiefly to the chemistry of photography, to which he made a number of important contributions. He published approximately 300 articles in the British Journal of Photography, as well as a book on photography entitled, A Manual of Photography: Intended as a Text Book for Beginners and a Book of Reference for Advanced Photographers. His publications include numerous papers on the chemical action of light. He is also known for his development of Carey Lea Silver, a photochemical, still in use today. Due to the loss of en eye during an experiment with picric acid, and his constantly ill condition, Lea spent most of his time in solitude. As a result, few chemists knew Lea personally, his only interaction with the science community was the publication of his studies. In 1895, he was elected to the National Academy of Sciences.
Death and legacy
Lea died on March 15, 1897 at his Chestnut Hill home from complications of a prostate cancer operation. He was interred at Laurel Hill Cemetery in Philadelphia. He ordered his notebooks destroyed, and they were, which has complicated research into his work. Along with other charitable bequests, Lea bequeathed his books and scientific apparatus to the Franklin Institute, plus funds to allow the institution to continue to purchase books and periodicals. At least one researcher believes that his long-term contributions to mechanical chemistry exceed the contributions to photography for which he received acclaim in his lifetime.