Vols. I-XI were issued in the Congressional series of U.S. public documents as 33d Cong., 2d sess. House ex. doc. 91, and also as Senate ex. doc. 78. Vol. XI was issued also (1861) as 36th Cong., 2d sess. Senate ex. doc. [no number] Supplement to vol. I (the material of which was published also in vol. XII, book I and book II) was issued in at least three forms: Supplement to vol. I, 1859, W.A. Harris, printer, as 35th Cong., 2d sess. Senate ex. doc. 46--Vol. XII, book I-II, 1860, T.H. Ford, printer, as 36th Cong., 1st sess. House ex. doc. 56, and Senate ex. doc. [no number] The reports of the Pacific Railroad surveys were prepared under the direct supervision of the Engineer Department. The volumes dealing with the soil, climate, geology, botany and zoology of the regions surveyed were edited and revised by Professors Henry and Baird, of the Smithsonian Institution. cf. Ingersoll, Hist. of the War Department. 1879, p. 292-293 For further information concerning the publication of the work and a list of serial numbers assigned to the volumes in the Congressional series of documents, see Checklist of United States public documents, 1911, p. 1274-1275