W. T. Brigham— Summit Crater of Mt Loa in 1880. 33 



Aet. III. — On the /Summit Grater of Mt. Loa in 1880 and 



1885. 



1. Notes on an Ascent in 1880, about three months before 



THE GREAT ERUPTION OF THAT TEAR ; BY W. T. BrIGHAM. 



On the first of May, 1880, fire was seen in the crater of 

 Pohaku Hanalei on the summit of Mauna Loa. Persons who 

 made the ascent saw a fire-fountain much like that observed in 

 1872, but no overflow followed, and the fires soon disappeared. 

 On the morning of July 26, I left Kilauea for Kapapala. The 

 next morning, while waiting at Stone's Panch for a guide over 

 the trackless beds of aa and clinker on the great mountain, an 

 earthquake occurred at 8.30 A. M. local time. It lasted three 

 seconds, and was accompanied by a loud subterranean noise 

 resembling that of the looms in a cotton mill. The vibration 

 was by no means so noticeable as the noise. Journeying over 

 a grazing land covered with coarse grass and dotted here and 

 there with blighted koa trees, we reached Ainapo (Land of 

 Darkness) at 1.45 P. M. Although at an elevation of at least 

 5,000 feet, the temperature was at 75°. Late in the afternoon 

 I mounted a fine mule that had been loaned me by a friend, 

 and, with Ahuai for guide, left the ranch. In 1864, with Mr. 

 Horace Mann, I climbed the mighty dome on foot on the 

 opposite side; but this path was, if possible, worse. The 

 forest had been burned, and the blackened stems of the trees 

 were dismal objects unless covered with the ahald, a gigantic 

 raspberry vine. The soil in these lower regions seems good, 

 but the ground is much broken, and so full of holes that it 

 would be very dangerous to ride out of the trail after dark. 

 Even in the afternoon, vapors ascended from these holes, which 

 often, if not always, communicated with caverns in the ancient 

 lava streams, and as the day waned the vapors became more 

 distinct. I found, as the average of several trials, that the 

 temperature was only two or three degrees higher than the out- 

 side air. As we ascended, the actual temperature of the vapor in 

 these holes increased, and of course the relative temperature 

 was much higher. I inferred from this that the inner moun- 

 tain mass was hotter than usual, as I had never observed so 

 great a difference before, and that an eruption was at hand. 



At the upper limit of vegetation we camped, giving our ani- 

 mals the little bundles of hay we had brought for the purpose. 

 The night was cold and on the morning of July 28, at sunrise, 

 the thermometer marked 52°. We broke camp at five o'clock 

 and reached the summit at half-past ten. A rougher mass of 



Am. Jour. Sci.— Third Series, Yol. XXXYI, No. 211.— July, 1888. 

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