chap. ix. Elevation of Chiloe. 233 



of this archipelago, I observed two terraces of gravel, 

 abutting to the foot of each other : at Lowe's Harbour 

 (43° 48'), under a great mass of the boulder formation, 

 about 300 feet in thickness, I found a layer of sand, 

 with numerous comminuted fragments of sea-shells, 

 having a fresh aspect, but too small to be identified. 



The Island of Chiloe. — The evidence of recent 

 elevation is here more satisfactory. The bay of San 

 Carlos is in most parts bounded by precipitous cliffs 

 from about ten to forty feet in. height, their bases 

 being separated from the present line of tidal action 

 by a talus, a few feet in height, covered with vegetation. 

 In one sheltered creek (west of P. Arena) instead of a 

 loose talus, there was a bare sloping bank of tertiary 

 mudstone, perforated, above the line of the highest 

 tides, by numerous shells of a Pholas now common in 

 the harbour. The upper extremities of these shells, 

 standing upright in their holes with grass growing out 

 of them, were abraded about a quarter of an inch, to 

 the same level with the surrounding worn strata. In 

 other parts, I observed (as at Pudeto) a great beach, 

 formed of comminuted shells, twenty feet above the 

 present shore. In other parts, again, there were small 

 caves worn into the foot of the low cliffs, and protected 

 from the waves by the talus with its vegetation : one 

 such cave which I examined, had its mouth about 

 twenty feet, and its bottom, which was filled with sand 

 containing fragments of shells and legs of crabs, from 

 eight to ten feet above high-water mark. From these 

 several facts, and from the appearance of the upraised 

 shells, I inferred that the elevation had been quite 

 recent ; and on inquiring from Mr. Williams, the Port- 

 master, he told me he was convinced that the land had 

 risen, or the sea fallen, four feet within the last four 

 years. During this period, there had been one severe 



