MoiDitaiiis of Hawaii. 



coral polyp does not generally flourish as around the islands where aftive volcanic 

 growth has ceased, consequently there is no natural breakwater to the strong adlion 

 of currents and waves. However hard the surface of a lava stream where it meets 

 the sea, its physical strudlure is such that the waves find easy access to the bubbles, 

 hollows, caves, so common in its structure, and after presenting water spouts for years 

 perhaps, the almost ceaseless beating of wave succeeding wave demolishes and sweeps 



away the ruins. It is probable that 

 Hawaii is not growing from accretions 

 of lava along shore more than it is wast- 

 ing b}- marine erosion. 



The time is near at hand for a more 

 complete ph3'siographic sketch of the 

 Hawaiian group than has hitherto been 

 possible, but at the present the portion 

 that most interests us is the cluster of 

 mountain peaks which marks the site of 

 the orifices from which the building of the 

 island of Hawaii (where alone are adlive 

 volcanoes) has been effedled. There are 

 five of these mountains prominent on the 

 face of Hawaii. In the northwest Mauna 

 Kohala, or Mt. Kohala, has long been 

 extinct and its slopes to the eastward 

 have been buried beneath the lava 

 streams from its mighty neighbor on the 

 northeast, Mauna Kea (White Mountain) . 

 The summit of Kohala shows little sign 

 of volcanic action, is swamp}', and the source of much water used for irrigation. 

 Its height is 5489 feet, but little more than that of Kilauea on the southeast. 



Mauna Kea (Fig. 4) also has long been extinct and its summit is covered with 

 cinder cones (Fig. 5 ), most of them with deep craters filled all the year with snow which 

 supplies the summit pool occupying the only crateriform depression on the summit 

 (Fig. 6 ) . Its depth is not known, as the only party which has made the ascent when the 

 pool was frozen over, so far as the author is informed, negleAed to ascertain this interest- 

 ing measure. Usually considered the highest of the Hawaiian volcanoes (13,825 feet), 

 its mass is less, and its real summit lower than that of Mauna Loa ( 13,675 feet), only 



the cinder cones give the superior height, and as these are composed of loose cinder 



[383] 



GREKN LiMU From kilauea, 

 SIZE. 



1789: NATURAI, 



