RIO DE LA LOZA, Leopoldo (ree'-o-dav-lah-lo'-thah), Mexican chemist, born in the city of Mexico in November, 1807; died there, 2 May, 1873. His father was an apothecary, and from early youth the boy assisted him in the laboratory, thus acquiring a taste for chemistry. After finishing his primary education, he entered the College of San Ildefonso, and was graduated m surgery in 1827, but he continued his scientific studies, and was graduated in 1830 in pharmacy, and in 1833 in medicine. In that year, when the cholera ravaged the country, Rio de la Loza received a public testimonial from President Gomez Farias for his services. In 1835 he began to give private lessons in chemistry and natural history, and in 1843 he was appointed professor of chemistry in the Medical school and the College of mines. He became successively professor of inorganic chemistry and chemistry applied to trades and agriculture in five different colleges, and in 1868 professor of analytical chemistry in the National school of medicine. During the American invasion of 1847, Rio de la Loza, as lieutenant of the academical company, took part in the battles of Pefion, Churubusco, and San Antonio. During the French intervention and the empire he was prevented by sickness from leaving the capital, but refused to accept any public employment. He was a member of many scientific societies in Europe, the United States, and the Spanish-American republics, and in 1856 received from the Society for the protection of industrial arts in London a gold medal for his chemical discoveries. He was one of the principal members of the commission for preparing the new Mexican pharmacopoeia (1874). His works include "Introduccion al estudio de la Quimica" (Mexico, 184!)) ; '" Estudio sobre el estafiate" (1850) : "Sobre los pozos artesianos y las aguas naturales de mas uso en la ciudad de M6xieo" (1854); " Un vistazo al lago de Texcoco; su influencia en la salubridad de Mexico" sus aguas; y procedencia de las sales que contiene" and "El Ahuautli" (1864); "El liquido tintoreo de la Baja California" and " Dictamen sobre el aerdlito de la Descubridora" (1873); and scientific pamphlets.