Above Lima the western chain of the Andes is composed of porphyritic tuffs and massive limestones, while the longitudinal valley of the Oroya is hollowed in carbonaceous sandstones.
An ephemeris and guide to Peru was begun by the learned geographer Dr Cosme Bueno, and continued by Dr Unanue, who brought out his guides at Lima from 1 793 to 1798.
The topographical labours of Cosme Bueno and Unanue were ably continued at Lima by Admiral Don Eduardo Carrasco, who compiled annual guides of Peru from 1826.
The leading Peruvian authors on constitutional and legal subjects are Dr Jose Santistevan, who has published volumes on civil and criminal law; Luis Felipe Villaran (subsequently rector of the university at Lima), author of a work on constitutional right; Dr Francisco Garcia Calderon (once president of Peru), author of a dictionary of Peruvian legislation, in two volumes; Dr Francisco Xavier Mariategui, one of the fathers of Peruvian independence; and Dr Francisco de Paula Vigil (1792-1875), orator and statesman as well as author, whose work, Defensa de los gobiernos, is a noble and enlightened statement of the case for civil governments against the pretensions of the court of Rome.
Only four volumes had been published at the time of his death, but he left a mass of papers and manuscripts which the government has put in the hands of the Geographical Society of Lima for publication.