24 Jlge of Forest Trees. [-^uly, 



The largest drifting iceberg that we saw, during a period of 

 three months in their vicinity, was estimated at about two miles 

 in extent, and elevated between two and three hundred feet in the 

 air. Should we take into consideration the specific gravity of 

 ice, which allows about eight parts beneath, to one above the sea, 

 we will be able to form some conception of the vast magnitude 

 of these floating mountains. One of these larger ones was seen 

 drifting along at the rate of two and a half knots an hour, at 

 which speed, on approaching Cornwallis island — one of the South 

 Shetland group — it suddenly became arrested in its course, the 

 anterior portion grounding, and remaining attached, while that 

 which followed, submitting to the powerful impulse of the cur- 

 rent, was swept around, describing a complete semicircle ere it 

 again became free. Should this part of the ocean's bottom, at 

 any future time, be elevated into dry land by the active energies 

 so peculiar to volcanic regions, the impressions made by this ice- 

 berg would furnish to the world a highly interesting subject for 

 geological speculation. When agitated by the waves, these 

 mountains of ice are frequently rent assunder with terrific explo- 

 sion, scattering their fragments far and wide over the surrounding 

 surface of the deep. In fine weather too, they are not unusually 

 s?en covered with penguins, whose chattering noise is often heard 

 at an incredible distance over the silent sea. 



AGE OF FOREST TREES. 



BY S. B. BUCKLEY. 



The age of our forest trees is not as great as we had supposed. 

 We thought that some of them had weathered the storms of at 

 least four or five hundred years, because here in America many 

 of the giants of the forest have remained undisturbed, nor can it 

 be truly said that our oldest trees have been destroyed by human 

 agency. We have very few trees that are three hundred years 

 old. We have lately taken considerable pains to asceitain the 

 ages of many in this vicinity, embracing many of the largest forest 



