A map of California, made by W.M. Eddy in 1853, has some interesting variations of the northwestern New Mexico nomenclature. The Muddy is set down as El Rio Atascoso (Sp., "Boggy") and Vegas Wash as Ojo del Gaetan (galleta grass?). Nearby was Agua Escorbada, where scurvy grass probably was found. There also was Hernandez Spring. There was an outline of the Potosi mining district. North of Las Vegas on a California map of 1864, was placed the "Old Mormon Fort." Reference by the reader is asked to the description of the Old Spanish Trail, which was followed partially by the line of the later Mormon road. On a late map of the section that was lost by Arizona to Nevada, today are noted only the settlements of Bunkerville, Moapa, Logan, St. Joseph, Mesquite, Overton and St. Thomas. There is a ferry at Rioville, at the mouth of the Virgin, and another is at Grand Wash. The name of Las Vegas is borne by a railroad station on the Salt Lake and Los Angeles line, a few miles from the Springs. There are the mining camps of Pahrump, Manse, Keystone, El Dorado and Newberry. The westernmost part of the triangle, at an elevation of about 3000 feet, is occupied by the great Amargosa desert, which descends abruptly on the California side into the sink of Death Valley to below sea level. There has been no development of large value in this strip. Its interest to Arizona is merely historical. Today, few Arizonans know that Pah-ute County once existed as an Arizona subdivision, or that Nevada took a part of Arizona, or that later, Nevada was given full sixty miles expansion eastward of her boundary line, at the expense of both Arizona and Utah. The natural boundary line in that section between Nevada and Arizona would have been the Virgin River. [Illustration: Map] The information contained in this chapter has been gathered from diverse sources, but largely from the records of the Church Historian at Salt Lake, wherein, practically, is the only history of the Mormon settlements of the southwestern section of what was and is known as "Utah's Dixie." The southern Nevada point had some value in a mineral way. As early as 1857, Mormons worked the Potosi silver mines, eighteen miles southwest of Las Vegas. Little data is at hand concerning their value. In Bancroft is found this sober chronicle: "Believing the mines to be lead, Brigham Young sent miners to work them, in anticipation of war with the United States, but the product was found too hard for bullets and the mines were abandoned." The Congressional Act of May, 1866, giving Nevada all that part of Arizona lying between the Colorado River and California, from about longitude 114, took from Arizona 31,850 square miles. This followed the extension of Nevada eastward for one degree of longitude. Annexed was appropriation of $17,000 for surveys. Missionaries of the Desert