astigmatic lenses, and was also the introducer of the system of numbering buildings according to the numbers of the streets, assigning one hundred numbers to each block. Spencer Fullerton Baird (1823-87), Naturalist and Secretary of the Smithsonian Institution, was also of Scottish origin. His works, including scientific papers, number over one thousand titles. Carlile Pollock Patterson (1816-81) did much to develop the United States Coast Survey. William Paterson Turnbull (1830-71), ornithologist, author of the "Birds of East Pennsylvania and New Jersey," a model of patient and accurate research, was born at Fala, near Edinburgh. Edward Duncan Montgomery, biologist and philosopher, was born in Edinburgh in 1835. Marshall MacDonald (1835-95), ichthyologist, pisciculturist, and inventor, engineer in charge of the siege of Vicksburg during the Civil War, and inventor of automatic hatching jars, was the grandson of a Scottish immigrant. Peter Smith Michie (1839-1901), soldier and scientist, born in Brechin, Forfarshire, graduated from West Point in 1863, served as Engineer in the Federal Army, and was afterwards Professor of Natural and Experimental Philosophy at West Point. William Healey Dall (b. 1845), palaeontologist to the United States Geological Survey, author of "Alaska and Its Resources," and author of hundreds of articles on Natural History subjects, was a grandson of William Dall of Forfarshire. Thomas Harrison Montgomery (1873-1912), specialist in zoology and embryology, was of Scottish origin. Robert Gibson Eccles, physician and chemist, born in Kilmaurs, Ayrshire, in 1848, discovered that benzoic acid and the benzoates are excellent preservatives of food. He has been Chemist of the Department of Indian Affairs, Professor of Chemistry in the New York School of Social Economics, President of the New York Pharmaceutical Association, etc., and has written largely on philosophy and science. Stephen Alfred Forbes (b. 1844), naturalist, educator, and writer on entomology and zoology, is of Scottish origin. Thomas Craig (1853-1900), Mathematician and Editor of the American Journal of Mathematics, was of Scottish parentage. Alexander Crombie Humphreys, born in Edinburgh in 1851, became President of Stevens Institute of Technology, Hoboken, in 1902. Anstruther Davidson, born in Caithness in 1860, Associate Professor of Dermatology in the University of Southern California, is also distinguished as a botanist and entomologist.