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

26 MEMORANDUM. 16° S. The deep sea-line should be kept in motion ; and if soundings be obtained, the bank should be pursued both ways, out to the edge, and in to that part already known. " Its actual extent to the eastward, and its connection with the shoals being thus ascertained, its further investigation may be left to more convenient opportunities. " At Rio de Janeiro, the time necessary for watering, &c. will, no doubt, be employed by the commander in every species of observation that can assist in deciding the longitude of Vil- lesagnon Island. " It is understood that a French Expedition is now engaged in the examination of the coast between St. Catherine's and the Rio de la Plata ; it would therefore be a waste of means to interfere with that interval ; and Commander Fitz-Roy should be directed to proceed to Monte Video, and to rate his chronometers in the same situation occupied by Captain King. " To the southward of the Rio de la Plata, the real work of the survey will begin. Of that great extent of coast which reaches from Cape St. Antonio to St. Geoi'ge's bay, we only know that it is inaccurately placed, and that it contains some large rivers, which rise at the other side of the continent, and some good harbours, which are undoubtedly worth a minute examination. Much of it, however, from the casual accounts of the Spaniards, seems to offer but little interest either to navigation or commerce, and will scarcely require more than to have its direction laid down correctly, and its prominent points fixed. It should nevertheless be borne in mind there, and in other places, that the more hopeless and forbidding any long line of coast may be, the more precious becomes the discovery of a port which affords safe anchorage and whole- some refreshments. " The portions of the coast which seem to require particu- lar examination are " 1st. From Monte Hermoso to the Rio Colorado, including the large inlet of Bahia Blanco, of which there are three manu- scripts in this office that differ in every thing but in name.