Who corresponded with the Smithsonian in its early years? From the 1850's to the 1870's, second Smithsonian Secretary Spencer F. Baird reached out to naturalists and collectors across the globe in pursuit of his dream to establish a national collection. Writing thousands of letters a year, Baird maintained a list of these correspondents in an atlas, identifying their names and organizing them by where they lived. ** Thank you for helping us make future research possible on this network of 19th century scientists and others who played a part in the first two decades of Smithsonian history. Would you be interested in trying your hand at the personal diary of one of Baird's correspondents, William H. Dall of the Western Union Telegraph Expedition?