(1791-1868), also an astronomer, became Professor of Astronomy in Vassar College, LL.D. of Columbia University (1887), and was the first woman elected to the American Academy of Sciences.  Lewis Morris Rutherfurd (1816-92), one of the most distinguished astronomers on the American Continent, obtained important results in astronomical photography, and by means of a ruling engine, designed by him in 1870, constructed the finest diffraction-gratings which had, up to that time, been made, was of Scottish ancestry.  George Davidson (1825-1911), born in England of Scottish parentage, geodetist and astronomer, one of the founders of the Geographical Society of the Pacific, Regent of the University of California, was retired after fifty years’ active field service of incalculable value to the cause of science.  William Harkness (1837-1903), born in Ecclefechan, Dumfriesshire, was executive officer of the Transit of Venus Commission (1882).  The task of reducing the observations and the hundreds of photographs was successfully undertaken by him although declared impossible by eminent British and German astronomers.  He was later Astronomical Director of the Naval Observatory and in 1897 made head of the Nautical Almanac.  Williamina (Mina) Paton Fleming (1857-1911), born in Dundee, discovered many new stars and wrote much of permanent value on her subject.  William Wallace Campbell (b. 1862), of Scottish ancestry, has been Director of Lick Observatory since 1901, and has written much on astronomy.

The most interesting Scot in connection with horticulture in the United States is Grant Thorburn (1773-1861), who was born in Dalkeith and left his native country for political reasons in 1794.  After trying a number of occupations he finally established himself as a seed merchant in New York, and the business is still carried on under his name.  Under the pen name of “Lawrie Todd” he contributed to the Knickerbocker Magazine and other New York periodicals, and supplied John Galt, the novelist, with much of the information incorporated in his “Lawrie Todd; or, Settlers in the New World.”  Thorburn also published two volumes of reminiscences, “Forty Years’ Residence in America,” and “Fifty Years’ Reminiscences of New York.”  William Adair, born near Glasgow in 1815, developed a profitable business as gardener and horticulturist in Michigan, and served as State Senator from 1861 to 1865, 1869-70.  Peter Henderson (1822-90), born at Pathhead near Edinburgh, founded the firm of Peter Henderson and Co., horticulturists and seedsmen, one of the largest firms of its kind in existence.  William Saunders (1822-1900), born in St. Andrews, planted and laid out several large estates, beautified Fairmount and Hunting Parks in Philadelphia, and the park and garden system of Washington, D.C., the National Cemetery at Gettysburg, etc.  William Macmillan, born in Nairnshire, laid out the public parks of Buffalo, and William R. Smith, a native of Haddingtonshire, was for many years Superintendent of the Botanic Gardens at Washington.  Robert Buist (1805-80), born in Edinburgh, was also one of the greatest horticulturists in the United States.