Herbert Brown came to Arizona in 1873 from the eastern U. S. at age 25 to seek his fortune. He would remain here until his death in 1913. During this period, southern Arizona was widely known for its newly discovered, exceptional bird life, many species occurring nowhere else in the U.S. This attracted leading ornithologists, such as Charles Bendire and Elliott Coues, who came to Tucson, the lower Colorado River Valley, and elsewhere in southern Arizona to conduct their studies. By the 1880s Brown was corresponding with these visiting ornithologists and collecting birds, nests, and eggs, advancing the science of ornithology in this new territory. These out-of-state ornithologists conducted their studies, taking their records and specimens back to their own institutions. By contrast, Brown's unequaled collections were deposited at the University of Arizona where he was the first Curator of Ornithology. Part 2 of his following field notes document, in Brown's own words, the previously untold story of a life-long passion for ornithology by Arizona's first resident ornithologist.

The Batamote Mountains represent a 14-16-million-year-old eroded shield volcano complex in the Basin and Range province near Ajo, Arizona. Analysis of Landsat 7 Enhanced Thematic Mapper “Plus” data and fieldwork enabled mapping the geology at 1:24,000 scale. Volcanic deposits and field relations indicate that mid-Tertiary eruptions initially involved mild explosions from at least six vents, evidenced by near-surface intrusive units surrounded by ash, oxidized cinders, and spatter deposits. The associated lava flows partly cover the pre-Batamote basement silicic volcanic rocks. At least three subsequent effusive phases emplaced multiple flows from a minimum of six vents on the cinder cone deposits and earlier lava flows. The last volcanic event involved fire-fountains that produced several short, thin, agglutinated flows, forming the steeper summit of the volcano. Extension and normal faulting caused rocks in the central portion of the Batamote Mountains to collapse; subsequent erosion of summit material left the amphitheater morphology seen today.