140 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



by Dr Wallich. Of ferns alone I have fully 200 species and 

 half as many mosses, of other plants comparatively few as the 

 season is not yet good for them, nor will be so until after the 

 rains. On my return, I must consult with you on the best mode 

 of publishing the plants of these islands. 



"I also visited the summit of Mouna Roa, the Big or Long 

 Mountain, which afforded me inexpressible delight. This 

 mountain, with an elevation of 13,517 feet, is one of the most 

 interesting in the world. I am ignorant whether the learned 

 and venerable Menzies ascended it or no, but I think he must 

 have done so, and natives assert that this was the case. The 

 red-faced man, who cut off the limbs of men and gathered grass, is 

 still known here ; and the people say that he climbed Mouna 

 Roa. No one, however, has since done so, until I went up a 

 short while ago. The journey took me seventeen days. On the 

 summit of this extraordinary mountain is a volcano, nearly 

 24 miles in circumference, and at present in terrific activity. 

 You must not confound this with the one situated on the flanks 

 of Mouna Roa, and spoken of by the missionaries and Lord 

 Byron, and which I visited also. It is difficult to attempt 

 describing such an immense place. The spectator is lost in 

 terror and admiration at beholding an enormous sunken pit (for 

 it differs from all our notions of volcanoes, as possessing cone- 

 shaped summits, with terminal openings), 5 miles square of 

 which is a lake of liquid fire, in a state of ebullition, sometimes 

 tranquil, at other times rolling its blazing waves with furious 

 agitation, and casting them upwards in columns from 30 to 170 

 feet high. In places the hardened lava assumes the form of gothic 

 arches in a colossal building, piled one above another in terrific 

 magnificence, through and among which the fiery fluid forces its 

 way in a current that proceeds 3^ miles per hour, or loses itself 

 in fathomless chasms at the bottom of the cauldron. The 

 volcano is 1272 feet deep, I mean down to the surface of the 

 fire, its chasms and caverns can never be measured. Mouna 

 Roa appears, indeed, more like an elevated tableland than a 

 mountain. It is a high broad dome, formed by an infinitude of 

 layers of volcanic matter, thrown out from the many mouths of 

 its craters. Vegetation does not exist higher than 11,000 feet, 

 there is no soil whatever, and no water. The lava is so porous, 

 that, when the snow melts, it disappears a few feet from the 

 verge, the ground drinking it up like a sponge. On the higher 



