284 TIERRA DEL FUEGO. June, 1834. 



ice had thawed all round it, so as to form a shallow pool of 

 water. It was a cube of nearly two feet ; and Mr. Bynoe 

 with a maul knocked off, and brought away, a piece as large 

 as a man's head. The iceberg was still floating, and drifting 

 outwards : even if it had been stranded in the immediate 

 neighbourhood, the block of granite would have rested on the 

 clay-slate of the surrounding mountains. For the parent rock 

 we must look to the higher parts of the range, near the head 

 of the sound. 



Again, a few miles to the northward I see in the chart 

 an Iceberg Sound, which no doubt was so called from the 

 number of floating masses of ice. It may be recollected 

 that in this latitude, on the opposite side of the Cordillera, 

 the plains of St. Cruz, at the distance of fifty and sixty miles 

 from the mountains, were strewed with great fragments of 

 rock. Of these, one was sixty feet in circumference, and 

 another, which was angular, measured five yards square ; — 

 both being partly buried in the gravel, so that their thick- 

 ness was unknown. As it is probable that the plains were 

 covered by the sea within a period geologically recent, and 

 as we absolutely know, that icebergs at the present day, 

 both in the same latitude and even further northward, are 

 transporting angular blocks from the opposite side of the 

 Cordillera, the explanation of the St. Cruz case through the 

 same means of transport, is rendered so evidently probable, 

 that we are not justified in doubting to receive it: more 

 especially as the unbroken surface of those plains, and the 

 terrace-formed valley, opposes a very great difficulty to the 

 admission of any violent debacle. The latitudes Avhich 

 we have now been talking of, correspond to the southern 

 extremity of Cornwall, and the northern provinces of 

 France. 



I will add only one other case ; namely, the occurrence of 

 glaciers at the level of the sea, in the gulf of Penas, lati- 

 tude 46° 40'. A glacier is represented in the charts as in one 

 part abutting on a flat swamp often inundated, and in ano- 



