372 W. T. BRIGHAM ON THE VOLCANIC PHENOMENA 



with great violence during a storm, leaping in vast white columns upon the shore above. 

 Islets of every form have been broken off from the cliff, and form with their black rugged 

 sides towering above the white surf a beautifully picturesque scene, which claims the admira- 

 tion of the passer-by. Vast bubbles have broken down, opening large caves, and the whole 

 surface of the rock is very uneven and broken. 



At Kaulanamauna the road leaves the coast and ascends a rather steep hill to the wooded 



region. Near Manuka a region of a-a commences, extending for many miles. No soil is 



found here, yet the traveller passes through forests of ohia-ha (Metrosideros polymorpha) where 



the trees average twelve inches in diameter, and sometimes exceed twenty, growing in the 



loose a-a, which forms a layer of unknown depth. It would seem unreasonable to select a 



pile of the slag from a blast furnace as a spot for potato raising, yet the Hawaiian makes a 



hole in the a-a, which looks quite like furnace refuse, plants a banana shoot, filling the hole 



with stones around the tender plant, and in ten months he gathers the fruit. Or he buries 



a sweet-potato cutting in the stones, covering the place with fern-leaves as a mulching, and 



in due time digs, it may be, a bushel of large fine potatoes. Awa (Macro-piper methysticum) 



grows well, and since the removal of all prohibitions against its culture, has been extensively 



planted. Beyond this ancient a-a, a more recent flow of the same material covers an extent 



of six miles, and its ridges, although scantily covered with vegetation, present a horrible 



scene of roughness and desolation. Piles of a-a fifty feet high, rents in the more solid pahoe- 



hoe beneath it, make the path uneven and tedious. The road is built with care, and where 



worn is good, but the fresh a-a, with which the bed is repaired, is as hard as glass, and although 



the iron shoes of the horses grind it down, the bare feet of the natives, or even the leathern 



soles of the foreigner, suffer exceedingly. Next this rough region which extends over nearly 



sixty square miles, a tract of pahoehoe stretches from the mountain to the shore, so hard 



that no tracks are worn by the horses, and it would be difficult to mark the road were it not 



for piles of stones erected for the purpose. This extends a mile, and is succeeded by a 



green grassy ridge of totally different character from any yet met with on Hawaii, and much 



resembling the rocky uplands of New England. This ridge of Kahuku seems to proceed 



from the upper mountain regions, with a slope of less than eight degrees, to the sea, where 



it terminates in a steep bluff surrounded by cone-craters of red earth. None of these 



cones are very large, and their sides are steeper than those of Oahu, resembling in outline 



cinder-cones rather than tufa, not being much furrowed or broken down. The grass-land 



extends five miles, and is then interrupted by the large valley of Waiohinu, where is the 



only running stream on this side of the island for a hundred miles. This brook rises 



from several springs not many miles up the mountain, and is clear, cold and never-failing, 



although small in volume. The Waiohinu Valley contains the principal settlement and the 



mission-station of the district of Ka-u ; it is very fertile, and many fruit-trees of temperate 



regions grow here with wonderful rapidity. 1 No valleys have been met before, but beyond 



for fifteen miles the country is broken with ridges and valleys, the former broader and 



rounder, and the latter smaller and shallower than those of Oahu or Maui. The soil is 



seldom more than a foot deep, but is productive, and the district seems to have been long 



exempt from the lava-streams from the mountain above. The explanation of this seems 



to be, that this part of the island was in ancient time by some great convulsion broken 



l The writer has seen in the garden of Mr. Spencer a peach-tree which had attained a height of ten feet, and was 

 wide spreading, six months from the time it sprung from the stone. 



