366 w - T. HRIGHAM ON THE VOLCANIC PHENOMENA 



They are composed of cinders and scoriae, generally of light specific gravity and reddish 

 tinge, sometimes hlack, and again colored with the hydrated oxide of iron, as if steam had 

 acted upon them while highly heated. 



On these cones we find the first appearance of sulphur. Kauai and Oahu were free from 

 it, and it is here in small quantities, much weathered, and quite impure ; with this exception 

 Hawaii is the only island where this common volcanic product is found. There is no steam 

 or vapor, and not even a hot spring to mark the forces once so active in this mountain. 

 A pool of cool and sweet water on the floor of the crater is carefully protected with stones. 

 This crater has never been surveyed, and the size is estimated by Mr. Drayton, of the 

 United States Exploring Expedition, to be from one to two thousand feet deep, and fifteen 

 miles in circuit. This is, however, much below the true circumference, which is nearer thirty 

 miles. The highest point of Haleakala was determined by barometer to be ten thousand 

 two hundred and seventeen (10,217) feet above the sea. 



Caves are of frequent occurrence near the top, and have every 

 appearance of lava bubbles. The rock of the crater is a hard 

 gray clinkstone, much fissured, and in many places resembling 

 artificial walls of cubical stone blocks ; lower down the mountain 

 the rock is softer and of a bluish tinge. A variety of feldspar, 

 which Prof. Dana named Mauilite, occurs in the loose sand of the 

 cones. 



Haleakala has been long extinct. No warm springs or steam- 

 jets, no mineral springs nor solfataras exist on Maui. Earthquakes 

 are not more frequent, nor are there indeed any signs to indicate 

 Fig. 23. plan of Haieakaia. that it will ever shake off its slumber of two thousand years, and 

 again pour forth lava. The slopes of Hana are as old to all appearance as those of Kauai, 

 and the soil is as deep and as productive. 



Old as is East Maui, West Maui is older still, as is shown by its more broken surface, 

 deeper soil, and extensive degradation. Its summit, Eeka, is six thousand one hundred and 

 thirty (6130) feet high. No single terminal crater exists, although there seem to be the 

 remains of several : the valley behind Lahaina being one, and Wailuku Valley perhaps 

 another. On a clear day, when the trade-wind clouds that usually hang over Eeka pass 

 away, the clustered peaks as seen from Ulupalakua more closely resemble the walls of a 

 central terminal crater than when examined from a nearer point. Indeed, no one who had 

 only seen this distant view would hesitate to declare that a crater of considerable size and 

 distinct outline crowned the mountain. 



Several of the valleys of Eeka have much the appearance of rents like the vast breaks 

 in Haleakala. The valley of Io, near Wailuku on the south-eastern slope, is deep and wild ; 

 several curious pinnacles or needles have been formed by the degradation of the very sharp, 

 thin ridges. The head of the valley forms an amphitheatre half a mile in diameter, and is 

 raised above the level of the valley-slope by a terrace nearly a hundred feet high. It is not 

 impossible that this was once a crater, and the lower part of the valley where the high and 

 nearly perpendicular walls closely approach each other, was a rent which the waters and 

 decomposition of the lava have enlarged. In no valley on the islands are the ridges so sharp 

 as here ; they often seem mere laminae set up on edge, — almost the leaves of this vast 

 volume of Nature. 



