Alvin Jewett Johnson (1827-1884), also known as A.J. Johnson, led the New York City publishing company which published Johnson's Family Atlases from 1860 to 1887. These atlases were published under his name alone or with Browning (1860–62) and Ward (1862-1866), and are fascinating because the sequence of atlas maps documented the growth of the United States during this quarter century, showing the step-by-step expansion of railroads and the development of new states, counties and towns. As the years went by, the maps were updated creating for each map a set of map states or variations.[1] These atlases and loose maps taken from them have become of increasing value to collectors and historians. In order for these loose maps to be of full use to historians for study (new counties showed up within two years of their creation and new states of the union almost as soon as they were announced) loose maps from these atlases need to be definitively dated. Collectors also need to know the true date of the maps; while some of the states/variations were utilized for up to two years, many changes occurred sometimes within one year, thus making some versions more plentiful than others.[2]