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

1832. FEVERS — DUST MASISEy's LEADS. 55 assertion is made. Wild guinea-fowls are found in flocks, and there are wild-cats in the unfrequented parts of the island ; but if induced to take a gun in pursuit of the guinea- fowls, I would advise a stranger not to overheat himself, or sleep on shore at night ; for fatal fevers have been contracted by Europeans, who were unguarded as to their health, while passing a few days in this hot climate, after being for some time accustomed to the cold weather of a high northern latitude. Except during the rainy season, the wind is always north- easterly, and then the sky is clear and the sun very powerful but a dry haze hangs over the island in a peculiar manner, and a quantity of fine dust, quite an impalpable powder, fre- quently settles on every exposed surface, even on the sails and rigging of a vessel, when passing near the islands. On the 8th of February our instruments were re-embarked, and, after swinging the ship to ascertain the amount of local attraction, we weighed anchor and sailed. By the compass fixed upon a stanchion in front of the poop, not twenty minutes difference of bearing could be detected, in any position of the vessel : the object observed being the highest point of a sharp peak, distant eleven miles. On the 10th we spoke the Lyra packet, going from England to Rio de Janeiro, and received a box from her, containing six of Massey's sounding-leads, those excellent contrivances which we frequently found so useful. These machines, as formerly made, did not answer for a much greater depth than one hundred fathoms ; because their hollow cylinder yielded to the pressure of the water : but Mr. Massey has since remedied that defect in their construction. On the 13th a very confused swell seemed to presage a change of weather. Hitherto the wind had been steady from the north-east, and the sky clear ; but on this day large soft clouds, light variable breezes, rain, and sometimes a short calm, showed us that we had passed the limits of the north- east trade wind. 14th. Similar weather, with a good deal of rain, but still breeze enough to keep us moving on our covirsei On the loth, the wind was steady from east south-east.