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

316 APPENDIX, June and July are much alike, but easterly gales blow more during July. The days being so short, and the weather cold, make these two months very impleasant, though they are, perhaps, the best for making a speedy passage to the westward, as the wind is then prevalent from the eastern quarter. I should say that December and January are the best for making a passage from the Pacific to the Atlantic Ocean, though that passage is so short and easily made, that it hardly requires a choice of time. For going to the westward, I should prefer April, May, or June, and should wait for a wind. Lightning and thunder are seldom known : violent squalls come from the south or south-west, giving warning of their approach by masses of clouds. They are rendered more formidable by snow and hail of a large size. There is a continual current setting along the south-west coast of Tierra del Fuego, from the north- west towards the south-east, as far as the Diego Ramirez Islands. From their vicinity the current takes a more easterly direction, setting round Cape Horn towards Staten Island, or off to seaward to the E.S.E. Much has been SEiid of the strength of this current ; some persons supposing that it is a serious obstacle in passing to the westward of Cape Horn, whUe others almost deny its existence. We found it run at the average rate of a nule an hour. Its strength is greater during west, — ^less or insensible during easterly winds. It is strongest near the land, particularly near the projecting capes or detached islands. This current sets rather from the land, which diminishes the dan- ger of approacliing the south-west parts of the coast : but there is, in fact, much less risk in approaching this coast than is generally supposed. Being high and bold, without sandbanks or shoals, its position accurately determined, and a bank of soundings extending twenty or thirty miles from the shore, it need not be much feared. Rocks, it is true, abound near the land, but they are very near to the shore, and out of a ship's way. A Une from point to point along the coast (beginning from the outermost Apostle), will clear all danger, excepting the Tower Rocks, which are steep to, and high above water. The preceding notices were written by me in 1 830, and I have not found it necessary to alter them materially. Taken in connection wth