60 DR. JOHN SCOULER. along the course of the little stream which supplies the aqueduct with water & had a fine opportunity of examin- ing the geological structure of the country. On the coast the granite extends along all that part of the bay to which my observations extended, these, however, were confined to the south western part. The granite near the sea is curious from the large size of its crystals of felspar, they are frequently two or three inches long ; the crystals of mica are also large. Near the coast the granite is pro- tected from the weather by a thin stratum of soil, but as we ascend to the elevation of a thousand feet the rocks are entirely exposed & destitute of vegetables. These rocks have a white bleached appearance, & consist of de- composing granite, so altered that its component minerals can with difficulty be recognized. The summit of this hill is about 2000 feet above the level of the sea, & is occupied by the Brazilian government as a signal post, for which purpose, it is admirably adapted as it com- mands a beautifull & extensive prospect of the neigh- bouring country. At the base of the hill the bay of Rio, the town [&] adjacent country apear like a map spread at one's feet. To the north Cape Frio sixty miles distant is to be seen, & the eye is lost in the boundless ocean ; to the south the bay of Bota Fogo with numerous little islands & promontories gives variety to the scene. The summit of the hill is composed of granite, but riot in so decomposing a state as that of the inferior part of the hill, & is of a more fine structure than that of the sea coast. The crystals of mica and felspar are much smaller, & the former is frequently of a dark [color], which is not the case with the mica of the coast. In the journey the variety of natural objects that at- tracted my attention were endless, every step I advanced presented me with some new gift [?] from [the] Flora & on every twig some beautifull insect attracted my attention.
