from the perfect and accurate instruments employed 1839 on both occasions.
The details of our observations are given in the Appendix, together with a letter I have received on the subject from Colonel Sabine, as it contains a useful caution and suggestion on barometrical measures.
The pile of stones erected by Lieutenant Wilkes's officers was pointed out to our party by the guides; but the notice left there by the Americans of their visit had been removed by some persons last year, and used by them, as the guides informed our officers, to light their fire. We did not learn the names of those who had been guilty of this ungracious act.
The day was splendidly beautiful, and our officers obtained a most magnificent view from their elevated position, overlooking the whole of the island: a circumstance of but rare occurrence, owing to the almost constant mist which encompasses the higher parts of the mountain, occasioned by the condensation of the vapour with which the atmosphere of this island is so fully charged.
Oct. 22.On the evening of the 22d a remarkable phenomenon was witnessed by us from the anchorage. We observed a very faint appearance of a pale rose colour rising behind the hills, to the left of Loo island, and twenty degrees west of the polar star: it increased in brightness and extent, until in twenty minutes it attained the altitude of thirty-three degrees, and bearing from N.W. to N. by E. by compass.