Four issue set on Fremont's famous second Western Expedition...

During the years of 1842–54 Fremont personally led and directed five western expeditions. This set of issues details his lengthy report on the second expedition (1843-4), to the interior of the Rockies and the Pacific Coast including northern, southern, central, and eastern Utah as well.
Great to have this extremely lengthy & detailed report in this famous title from the nation's capital.
Each complete in 4 pages, the issue of the 28th has an irregular bottom margin not affecting any text, generally all in good condition.