¹Matthews, along with his brother and father (an Irish surgeon who had settled in the United States in 1846), had served in the Union Army during the war between the States. He received his own medical degree in 1864 from the University of Iowa and was afterwards appointed assistant surgeon at the Rock Island Arsenal in Illinois. Matthews was quite familiar with the west and Southwest, having been posted both to Fort Union, Montana and Fort Wingate prior to his position with the USAMM in Washington (Schevill, 1948/1949).