J. D. Dana — History of the Mt. Loa Summit Grater. 25 



again and went to a height of 1000 feet. Large stones and 

 rocks were thrown up, some weighing 100 tons ; and so many 

 that they seemed to fill the air. The lava of the fountains is 

 stated to have had a rotation " to the south." Below the 

 fountains, the lava flowed in a rapid stream to the sea, making 

 a descent of 2000 feet and reaching the shore in two hours. 

 The rate of flow is stated to have been 10 to 25 miles an hour.* 

 A cinder or tufa cone was made at the place of discharge into 

 the sea, which was first an island, and afterward became joined 

 to the land by the flowing lava. The eruption ceased in the 

 night between the 11th and 12th, after only five days' activity. 

 The lava is mostly pahoehoe, with some areas of aa, and ex- 

 tremely chrysolitic. At the crack above the main outburst, 

 the lava which escaped was light brownish scoria, which was 

 drifted by the winds, along with much capillary glass. The 

 season was one of unusual rains over the mountain. 



Prof. C. H. Hitchcock examined the region of eruption in 

 June of 1885, both above and below the extremity of the pali 

 (precipice) represented on the map by the west side of the 

 lava-stream. He states the following facts in a letter, of May 

 30, 1888, to the author. The fissure whence the lavas of 1868 

 flowed " is in exact continuation of the pali, up the mountain. 

 I traced it fully three miles. For much of the way it makes a 

 narrow canon 40 or 50 feet wide at the maximum, and so deep 

 that it is dangerous to explore it. In the lower part heat was 

 still evident. The fissure is most prominent where the lava is 

 in greatest amount. Its borders have the smoothed appearance 

 that would result from an outflow of lava over its edge. The 

 very uppermost point reached we estimated, from our aneroid, 

 to be 3100 feet above Mr. Jones's ranch near the north end of 

 the pali. There is no cone at that point, as there is at the 

 sources of the 1855 and 1881 flows which I also visited. Every 

 fact harmonizes with the view of a rent three miles long, allow- 

 ing the accumulated lava to discharge in one or two days' time, 

 instead of oozing out of a single small orifice for months. The 

 connection of the fissure with the pali shows clearly the exist- 

 ence of a fissure along its whole length, which has been the 

 seat of eruptions in ages past. This Kahuku flow was analo- 

 gous to that of Kilauea in 1840. 



1870, January 1. — During the first two weeks of January, 

 much "steam and smoke" arose from the summit crater, f In 

 the course of the preceding month, Judge Hitchcock, of Hilo, 

 with others, visited this crater and found much escaping steam, 



* Pacific Commercial Advertiser of May 9th, 1868. See also W. L. Green's 

 Vestiges of a Molten Globe, pp. 294-303. Mr. Green does not intimate that Mr. 

 Whitney's description is exaggerated. 



f Coan, this Journal, xlix, 393, 1870, letter of Jan. 24, 1870. 



