John Lawrence Smith, an American chemist and mineralogist, born near Charleston, S. C, Dec. 16, 1818. He graduated at the university of Virginia and at the medical college of South Carolina, and for three years studied chemistry, physiology, physics, mineralogy, and geology in Europe. In 1844 he commenced the practice of medicine in Charleston, delivered lectures on toxicology, paid attention to agricultural chemistry, and ascertained the character and value of the marl beds extending 100 m. back of Charleston. In 1846 he was employed by the Turkish government- to suggest improvements in the cotton culture in Asia Minor, and accepted the appointment of mining engineer. He remained four years, and in 1849 made a report on the "Thermal Waters of Asia Minor." His mining researches in Asia Minor led to the subsequent discovery of emery and corundum in localities in the United States. After his return in 1851 he invented the inverted microscope, and was professor of chemistry in the university of Virginia, and subsequently in the medical department of the university of Louisville, Ky., and is now (1870) scientific superintendent of the Louisville gas works.

In 1867 he was a commissioner to the Paris exposition, making a report on " The Progress and Condition of Several Departments of Industrial Chemistry," and in 1873 to the Vienna exhibition. In 1872 he was elected president of the American association for the advancement of science. His scientific reports are numerous, and his original researches, about 50 in number, have been collected in a volume, "Mineralogy and Chemistry: Original Researches " (8vo, Louisville, 1873). (See Emerald, and Emery).