This record unit consists of papers and records regarding the Smithsonian's meteorological observation projects in the 1850s and analysis and publication of meteorological data in the 1870s; incoming correspondence to the Smithsonian, circa 1852-1873, from observers and others working on meteorology; another series of correspondence, reports and notes, 1853-1875, and undated; outgoing correspondence, 1853-1854, of Lorin Blodget, an assistant at the Smithsonian for meteorological affairs; a manuscript copy of part of the 1873 Smithsonian Annual Report on meteorological data preserved at the Smithsonian; data on mean temperatures, annual rainfall, and barometric pressures in the United States and other countries of the Americas, mostly for the years 1850 through 1873, and prepared for publication; a small and uneven collection of clippings on meteorology, 1856-1873; records of meteorological observations and loan of instruments, 1856-1873; and miscellaneous and fragmentary original records of meteorological observations.