Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.2): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

1835. CONSTITUCION — PLAK EXPLANATION. 483 her, and at once set on foot an examination of the coast of Peru, similar to that which Mr. Sulivan had completed of tlie coast of Chile. Don Francisco Vascufian had authorized the sale of his vessel at Callao : she was purchased by me for =£'400, and immediately fitted out afresh. I could not spare Lieutenant Sulivan to remain on the coast of Peru, while the Beagle would be crossing the Pacific, on her return to England by way of the Cape of Good Hope ; but there was Mr. Usborne, able and willing to undertake the task, who, from his station, could be spared without prejudice to the duties yet remaining to be executed on board the Beagle, and a l^etter man for the purpose I could not have desired. With him Mr. Forsyth volunteered to go, and Commodore Mason was prevailed upon to allow Mr. E. Davis, a master''s assistant of the Blonde, to join the little expedition ; who, with seven good seamen, and a boy, volunteers from the Beagle, completed Mr. Usborne's party. A stranger might well smile at the idea of such a boat affair being started to survey, in eight or at most ten months, the whole coast of Peru, from Paposo, near Atacama, to the River Guayaquil ; but the task was completed ; the charts are now en- graved; and very soon seamen will be able to test their accuracy. Most people are aware that the coast of Peru is free from storms ; that the wind blows moderately along the land or from it ; and that there is little or no rain. Consequently, as the sea is seldom much disturbed (except by a south-west swell), and there are neither ' races ' nor dangerous streams of tide, an open boat might undertake such a task, if safety alone were to be considered, provided that she did not try to land in a siu-f. The real impediments to surveying that coast are — the surf caused on those steep rocky shores by an occasional heavy swell, almost amounting to rollers, from the south-westward the delays and doubts created by prevalent fogs ; and the loss of positions, as well as time, consequent upon being drifted by currents during a calm. Mr. Usborne had also to prepare for, and provide against, as much as possible, difficulties of a very different nature — those arising out of the disturbed state 2 r 2