One of the sequence of Johnson maps of the American southwest. This is the first version to show Nevada with its current borders. Nevada had become a state in 1864, but did not gain its southern tip, below the 37th parallel, until 1867. This map was issued just as the trans-Continental railroad was nearing completion, and the paths of the Union Pacific R.R. and the Central Pacific R.R. are shown reaching towards each other, paralleled along part by the route by the Pony Express.