Page:History of the Royal Astronomical Society (1923).djvu/172

 146 HISTORY OF THE [1860-70 The value of the work as a preliminary survey of the Northern Heavens not of high precision but of enormous utility for the identification of stars to the ninth magnitude has received full recognition from grateful astronomers, who to this day plot fields of stars from Argelander's charts and use Argelander's sign manual, such as B.D.+3I 2327, in their constant references. His assiduous assistants Schonfeld [1828-91] and Kriiger [1832-96] are not forgotten.* That this work was at once recognised as worth the trouble spent upon it was proved by the continued efforts to secure a similar survey of the Southern Heavens. In 1862 our Council, on the initiative of Carrington, who was doubtless moved by the publication of Argelander's Durchmusterung volumes, appointed a Committee (Airy, Carrington, and Hind) to report on the best means to be pursued to carry out a survey of the stars of the Southern Hemisphere. The Committee suggested the Cape, Sydney, Williamstown (Melbourne), and Hobarton, as possibly providing men willing to undertake the work. It would require six or eight years to record 300,000 stars twice and to revise ; a special staff would be needed, but the cost of the instrumental requirements might be taken as negligible. In 1863, Strange's name was substituted for Airy's, and a few months later the names of Pritchard, Hodgson, and Manners were added. Meanwhile enquiries had been made of Maclear at the Cape, Pogson at Madras, Smalley at Sydney, Ellery at Melbourne, and Todd at Adelaide, resulting in Maclear's accepting the polar segment from the south pole to declination 50, and Ellery 's undertaking the zones between declinations 20 and 40. In 1864, Adams was appointed to the Committee in place of Hind, and in 1866, Stone, who also had joined the Committee, was instructed to write and express satisfaction at Ellery 's progress. But the undertaking languished. And though, as will be later recounted, at Argelander's instigation the huge undertaking of the Astronomische Gesellschaft was initiated in 1867, the Southern Heavens had to wait for their complete survey until Gill and Kapteyn carried out the photo- graphic survey in the years 1893-1901. Meanwhile, Schonfeld, who had left Bonn in 1859 for Mannheim, but took much of the Bonn work with him to complete it, had returned to Bonn as Director of the Observatory on the death, in 1875, of his former chief and life-long friend, Argelander. He at once embarked upon his extension of the survey as far as declination 23, and by 1886, plotting every star of Argelander's list on a single circular map of the Northern Hemisphere on an equal-surface projection. Many of his earlier books, which did much to spread an interest in Astronomy, were published in this decade.
 * Richard Proctor (1837-88) made an interesting chart by laboriously