On quitting St Jago we steer southerly for the Rio Grande, which is on the north of Ethiopia, beyond which we come to the high mountain of Sierra Liona, the summit of which is continually enveloped in mist, out of which thunder and lightning almost perpetually flashes, and is heard at sea from the distance of forty or fifty miles. Though the sun is quite vertical in passing over this mountain, and extremely hot, yet the thick fog is never dissipated. In our voyage we never lose sight of land, yet keep always at a considerable distance, carefully observing the declination of the sun, and keeping a southerly course till we arrive in _four degrees on the equinoctial_[7], when we suddenly change our course to the south-east, keeping the Ethiopian coast always on our left hand in our way to the island of St Thomas. On this coast, between the tropic and the equinoctial, we never meet with any hard gales, as storms are very rarely found within the tropics. On nearing the land, the soundings in many parts of the coast do not exceed fifty _braccia_, but farther out the depth rapidly increases, and the sea usually runs high at a distance from the land. When we arrived at Rio del Oro, as mentioned before, we observed four stars in the form of a cross, of an extraordinary size and splendour, elevated thirty degrees above the antarctic pole, and forming the constellation called _il Crusero_. While under the tropic of Cancer, we saw this constellation very low; and, on directing our _balestra_[8] to the lowermost of these stars, we found it to be directly south, and concluded that it must be in the centre of the antarctic polar circle. We observed the same constellation very high when we were at the island of St Thomas; and remarked that the moon, after rain, produces a rainbow similar to that occasioned by the sun during the day, except that the colours were dim and ill-defined. On leaving the straits of Gibraltar, I did not observe any sensible change on the ebb and flow of the sea; but when we approached Rio Grande, which is eleven degrees to the north of the equinoctial, we observed a considerable tide at the mouth of that river, and the rise in some places was much the same as on the coast of Portugal, whereas at the isle of St Thomas it was nearly the same as at Venice.