S. Powers — Notes on Hawaiian Petrology. 265 



ported to the early missionaries. Mr. L. A. Thurston, 

 of Honolulu, has, however, authenticated a tradition to 

 the effect that there was a lava flow from the southwest 

 side of the mountain near sea-level about 1750. 7 The 

 event took place about three generations ago and part of 

 a Hawaiian village was destroyed by the lava. 



The 1750 now, east of Makana, issued from the black, 

 breached cone called Pimoa. The rock is a very fresh 

 aa basalt filled with olivine crystals. The aa streams 

 have covered other fresh flows in the vicinity and have 

 coalesced to form a rounded peninsula (fig. 3). No stone 

 walls were seen covered by the youngest lava 8 as were 

 covered by the Hualalai flow of 1801, but none would be 

 expected in such a barren waste of lava flows unless 

 within a few yards of the shore. The appearance of the 

 lava and of the Pimoa cone from which it came, at an 

 elevation of about 1,100 feet, are in accord with the tradi- 

 tion. This flow probably was the closing activity of the 

 volcano as the cones in the crater of Haleakala must be 

 dated as earlier. The volcano now appears to be extinct 

 in spite of reports from one ranch on the side of the 

 mountain that occasional .underground rumblings are 

 heard. 



Rows of young cones are found on the sides of Halea- 

 kala arranged, in general, along lines radiating from the 

 summit of the mountain. From many of the cones radial 

 flows may be traced. Several rows of ash cones extend 

 toward Hana, on the east side of the mountain, but the 

 tropical jungle prevents an examination of the upper 

 cones. Puu Kauiki, on the shore, is a red lapilli and ash 

 cone traversed by olivine-basalt dikes. Parallel rows of 

 cones extend from White's Hill the highest point of the 

 mountain, toward Ulupalakua on the southwest. Near 

 Ulupalakua they diverge into many lines from which the 

 recent flows in that vicinity have poured into the sea. 

 One of these lines of weakness in the mountain runs 

 through Puu Olai, a red ash and lapilli cone near Makana, 

 and through Molokini, the" semi-circular tuff crater 9 be- 



7 Father Ed. Bailey was told in 1900 or thereabouts by a native that when 

 the latter 's great grandfather was a boy about 10 years of age a lava flow 

 destroyed their village (Honoualua), running around a house from which 

 a woman and child failed to escape. 



8 W. A. Bryan reports that a stone wall was buried by this flow (Natural 

 History of Hawaii, Honolulu, 1915, p. 147) but this was not found, by the 

 writer. 



9 This tuff, of unknown composition, resembles that composing Diamond 

 Head and Punchbowl, but no specimens of hard basalt were present in the 

 collection of material made for the writer by the vessel of the Lighthouse 

 Service. 



