Library includes 15,000 items spanning the 13th-19th century including manuscripts, books and pamphlets in astronomical literature, comet tracts and broadsheets & academic societies' publications and, in 1872, the library of Charles Babbage (of around 2500 items) was acquired. Crawford's collection policy was based on that of the Pulkova Observatory near St. Petersburg and contains first editions of all major works on astronomy and related subjects. The Archives comprises the notebooks, correspondence and other papers of the Astronomical Institution from 1764, Astronomers Royal for Scotland, 1834-1980; and the 26th Earl of Crawford, 1871-1875. Also included are observations and calculations; records on transit circle, time service, photometry, spectroscopy; & lecture notes. The Charles Piazzi Smyth Archives (Astronomer Royal for Scotland, 1845-1888), consisting of sketches; pocket notebooks; journals; watercolors; manuscript volumes re teaching of astronomy at the University of Edinburgh; diaries; student notes on geology and mineralogy; notes on cloud taking camera; notes on the Great Pyramid; solar spectra manuscript; photographic plates from Tenerife, Isle of May, Russia, Egypt, etc., 1856-1896.