The “Lunar Rocks” had been a subject of high admiration, and intense puzzle, from the first day of our tenanting Guajara. We had complete command over them as to view; for, from the top of our cliff, or volcanic wall, we gazed almost vertically down upon them as they lay, or rather rose, and shot up, on the floor of the gigantic crater. Was it as a Gordian method of solving the difficulty of their origin, that Von Buch left them entirely out of his large map; otherwise a most excellent one, specially called a carte physique, and engraved so laboriously in the line manner, as to leave no part of the paper unburdened with careful conventional shading. Suffice it that they are not there; yet were in earlier Spanish charts; and are also in that more recent map of MM. Barker-Webb and Berthelot, which the friends of the great German geologist have so unhesitatingly condemned in everything.

Look down at any time of the day from Guajara, and these “Lunar Rocks” riveted your attention. In the middle of the day they gleamed again with bright greens, reds, blues, purples, and whites, as well as with yellows and browns. The greens, and likewise all those other colours being due, to the nature of the rock. Not to vegetation certainly; for of that there was practically nothing, even in the plain about, save the barely visible, far between dottings of globular retama bushes; the living, dark grey; the dead (see Photo-stereograph, No. 6), cinereous white.