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. MISTAKE ABOUT LEUBU 471 explain. A momentary reference to my instructions shows that the Beagle was only expected to " correct the outline, and to fix the positions of all the salient points"* of the coast be- tween Childeand Topocalma (near Valparaiso); and the Beagle's charts of that coast prove that a great deal more was accom- plished than was thought practicable when those instructions were framed. Between Cape Tirua opposite Mocha, and Tucapel Head, the shore was laid down on our chart as determined by trian- gulation connected with the ship under sail, her distance from the land varying from one mile to five miles ; and as no river was seen thereabouts, nor any break in the coast-line where a river's mouth could be, our chart contained merely a note, saying, " River Lebo, according to the Spanish chart." Now, the erroneous place of this Lebo (meant for Lei'ibu) was twenty miles south of the real position, which, shut in behind Tucapel Head, could never have been seen from any vessel sailing- past, however near the shore she mighthave been. The coast-line in the Beagle's chart was proved to be perfectly correct ; but the place of the Leiibu, which could only have been obtained by landing, or having a local pilot on board, was not known ; and not being a navigable river, I did not deem it of suffi- cient consequence to be worth our delaying on an exposed coast, without an anchorage or a landing-place — so far as I then knew — while it was sought for. Considering the multiplicity of places the Beagle had to visit subsequently, I often found it necessary to sacrifice such details as seemed to me of least consequence. Every seaman knows how very difficult it is to make out the openings of some small rivers, while he is sailing along a coast little known, and all marine surveyors know that there is seldom any way of making sure of such openings without landing ; or entering them in a boat. I do not say this to excuse neglect — not feeling culpable — but simply to explain how the case stood. On each day, when near the land, guns were fired at inter- vals, and sometimes three or four were fired at once; blue * Hydrographer's Memorandum, p. 31.