The Andes of Southern Peru / Geographical Reconnaissance along the Seventy-Third Meridian

The account documents a geographical reconnaissance of the southern Peruvian Andes along the 73rd meridian, tracing sharp transitions from humid lowland forest through high snow-covered passes to the arid coastal plain. It interweaves human geography—regional population types, river canyons, rubber exploitation, shepherding valleys, and coastal conditions—with systematic physiography, climatology, meteorological records, glacial features, and geologic interpretation. Field methods and topographic sheets are described and used to support observations, and the narrative emphasizes how steep environmental contrasts within short distances shape land use, local customs, and the distribution of people and ecosystems.