S. Powers — Notes on Hawaiian Petrology. 267 



tain in a northwest direction toward the sea near Makala- 

 wena. The greatest, and probably the first 1801 out- 

 break, occurred near the summit of the mountain at 

 Kaupulehu, and from it lava streamed to the sea near 

 Kiliolo, 11 miles distant, destroying the Paiea fishpond 

 and the Hawaiian villages at the shore. Farther down 

 the mountain three small flows, each a hundred yards in 

 length, are seen emanating from the same line of weak- 

 ness at elevations of 2,400 to 4,000 feet; and 110 feet 

 below the Kona-Kohala highway the Huehue flow broke 

 out of a little cavern in the older pahoehoe at an eleva- 

 tion of 2,200 feet, flowed over a stone wall and poured 

 down the slope of the mountain. The flow was appar- 

 ently fed from a number of openings now concealed by 

 the lava, as in the center of the flow, far below the road, 

 there is a blackened cone. The flow entered the sea be- 

 tween Keahole Point and Makalawena. While the Hue- 

 hue flow and the smaller flows above are pahoehoe, the 

 larger flow on the north is aa. 



Mauna Loa is being built up by flows from two major 

 lines of weakness, a west-east line running from Mokua- 

 weoweo in the direction of Olaa and a northeast-south- 

 west line extending toward Kahuka. Flows have alter- 

 nated on the two sides for a number of years until in May, 

 1916, and again in September, 1919, flows appeared in 

 Kahuku near the 1907 flow. 12 Many cones are seen 

 along the first line and it will be possible to study them 

 with the new trail up the mountain. On the other side 

 of the mountain cones are not as abundant. One of the 

 larger, Puu o Keokeo, does not represent a separate 

 crater as has been supposed. 13 Along the southwest 

 shore from Kapua to Ka Lae rows of cones are seen fol- 

 lowing the shore-line. It is possible that these cones owe 

 their origin to the reaction of seawater on the hot lava 

 pouring into the sea, as was apparently the origin of 

 the Nanawale cones in Puna at the end of the principal 

 1840 flow from Kilauea, and of the cones at the end of 

 the 1868 Mauna Loa flow in Kau. 14 No similar tangential 



12 H. O. Wood: Notes on the 1916 eruption of Mauna Loa, Jour. Geol 

 vol. 25, pp. 322-336, 467-488, 1917. 



13 A suggestion by S. E. Bishop cited by Hitchcock in Hawaii and its Vol- 

 canoes, Honolulu, 1911, p. 148. 



14 Mentioned by W. L. Green, Vestiges of a molten Globe, vol. 2, p. 178, 

 Honolulu, 1887. Also see observations by Eev. T. Coan on the 1885 Mauna 

 Loa flow, cited by W. T. Brigham, Volcanoes of Kilauea and Mauna Loa, 

 Mem. B. P. Bishop Museum, Honolulu, vol. 2, No. 4, p. 74, 1909. 



