This rare, large map is considered by Wheat to be a landmark in the mapping of the region and "one of the most beautiful maps every published by the Army." According to Wheat there are several reasons for its importance. First, it is the first to show a trail to the junction of the Green and Grand Rivers. Second, he praises the map for its depiction of numerous routes of other explorers. Finally, it demonstrates the culmination of the process developed by Egloffstein to convey the idea of altitude. The process used a combination of extremely fine lines and applying acid to the plate for varying times, thus giving the map a remarkable 3-dimensional realism unmatched in the period. It is also the first to correctly establish the relationship between the San Juan and Colorado Rivers. The map covers Arizona, Utah, New Mexico and about 30% of Colorado.

The map is accompanied by Capt. Malcomb's "Report of the Exploring Expedition from Santa Fe, New Mexico, to the Junction of the Grand and Green River", produced in 1859 but not issued until 1876 due to the Civil War. The report includes 22 plates (11 tissue-guarded chromolithographic landscape views, 3 b&w views, and 8 plates of fossil specimens). Color plates drawn by J. J. Young from field sketches provided by J. S. Newberry. Quarto, 152 pp., hardbound in original brown cloth with new spine.

References: Wheat (TMW) #983.

Condition:

The large folding map has light toning along the folds and has been professionally backed with tissue to reinforce and repair numerous long fold separations (B). The report is very good (B+) including the plates, which are generally clean and bright. The text is lightly toned with some occasional notations in the margins, there is a library stamp on the title page, and Plate X has two extraneous vertical pen lines in the image. Original boards have minimal wear with original title label pasted on new spine.