Bolivia, Peru. Forbes, David (1861). ‘Geology of South America – part I, Bolivia and Peru, with Notes on the Fossils by Prof Huxley, JW Salter and T. Rupert Jones’. Extract from Quarterly Journal Geological Society, v. 17, pp 7 to 84 + 6 plates. Text age-toned, but clean. Two single page sized colour printed maps, long foldout section and three fossil plates. Plate 1 is ‘Geological Sketch-Map of part of Bolivia and Peru’ 1:700,000 approx scale, colour. Plate 2 comprises two b/w traverses from the coast inland in significant detail at 1:126,720.  Plate 3 comprises three comparable sections from 1842, 1856 and 1860 revealing the development of detail over the two decades. In good to very good condition.