Interesting large format map, hand colored by counties. Many early counties not yet present, including Orange, Riverside and Imperial. While ostesibly a railroad map, the only railroads are in Santa Clara, Monterrey and Los Aglees Counties. Even San Diego lacks rail service. Excellent detail.
Asher & Adams was a New York publishing firm known for their atlases. Notably, their maps were some of the first to prominently exhibit railroad lines, even if this meant a slight reduction in topographical detail. They specialized especially in state and county maps of the United States.