taken place so recently in the crust of the globe, there can be no reason for supposing former epochs of excessive violence. These modern strata are very remarkable by being threaded with metallic veins of silver, gold, copper, etc.; hitherto these have been considered as appertaining to older formations. In these same beds, and close to a goldmine, I found a clump of petrified trees, standing up right, with layers of fine sandstone deposited round them, bearing the impression of their bark. These trees are covered by other sandstones and streams of lava to the thickness of several thousand feet. These rocks have been deposited beneath water; yet it is clear the spot where the trees grew must once have been above the level of the sea, so that it is certain the land must have been depressed by at least as many thousand feet as the superincumbent subaqueous deposits are thick. But I am afraid you will tell me I am prosy with my geological descriptions and theories... Your account of Erasmus' visit to Cambridge has made me long to be back there. I cannot fancy anything more delightful than his Sunday round of King's, Trinity, and those talking giants, Whewell and Sedgwick; I hope your musical tastes continue in due force. I shall be ravenous for the pianoforte... I have not quite determined whether I will sleep at the 'Lion' the first night when I arrive per 'Wonder,' or disturb you all in the dead of night; everything short of that is absolutely planned. Everything about Shrewsbury is growing in my mind bigger and more beautiful; I am certain the acacia and copper beech are two superb trees; I shall know every bush, and I will trouble you young ladies, when each of you cut down your tree, to spare a few. As for the view behind the house, I have seen nothing like it. It is the same with North Wales; Snowdon, to my mind, looks much higher and much more beautiful than any peak in the Cordilleras. So you will say, with my benighted faculties, it is time to return, and so it is, and I long to be with you. Whatever the trees are, I know what I shall find all you. I am writing nonsense, so farewell. My most affectionate love to all, and I pray forgiveness from my father. Yours most affectionately, CHARLES DARWIN. CHARLES DARWIN TO W.D. FOX. Lima, July, 1835. My dear Fox,