GEOLOGY AND TOPOGRAPHY OP IIAWAIL 163 



As usual, the fii'st inliination of Mc1ivit\- was ^iven liy the lurid fi'lare over the 

 summit crater. Ou -lamiary 9tli sli,uli1 ('ai1li(|uak-cs wen- IVIl on Hawaii, and 

 on the night of January 10th, PX'T, Mauna l^oa was crowned with a bright 

 light. A few hours later the molten tiood broke through the walls of the great 

 mountain on the southerly or Kahuku side of the dome, at a place 8,500 feet 

 above the sea and at a point abont one half the distance from the sea to the 

 summit of the mountain. The tiow in its course down tlie mountain passed 

 near the path of the 1887 flow. About the middle of its course the stream 

 divided into two main divisions, with smaller branches to right and left. The 

 two main liranches crossed the government road five miles apart on the night 

 of January- 13th. i. e., within three days from the time of the oulbi-eak. Neither 

 of the streams in their divided and Aveakened condition had force enonuh 1o 

 reach the sea. Both came finally to a halt on January 24th, about four mih-s 

 from the shore and within ten days from the time the flow bi-oke out on the 

 mountain side. It has been estimated that in the upper part of the stream the 

 lava flood advanced at the rate of seven miles an hour, but lower down its ad- 

 vance was slow and majestic. Several hundred people from the vicinity and 

 from the other islands of the group rushed to the scene and were favored with 

 a splendid view of nature's most awe-inspiring spectacle. 



On November 25, 1914, white fumes were seen rising above the crater on the 

 summit of ^Eauna Loa. By evening the fume eolunnis were seen to rise to a 

 height of 6,000 feet or more above the mountain, and, illuminatetl l)y the light 

 from beloAv, presented a spectacle of splendid magnitude and beauty. It was 

 generally thought that this manifestation was the percursor of the usual type of 

 outbreak and flow, but this event did not transpire. After a short period of vary- 

 ing activity, confined entirely to the crater of ^lokuaweoweo, the outbreak sub- 

 sided until no activity was visible from the observatory at Kilauea. 



Lava Discharged in the li)07 Flow. 



Mr. E. D. Baldwin has estimated that the flow of 1907 covered nine hun- 

 dred acres of rough land and that a volume of two hundred million cul)ic 

 yards of basaltic material was poured out. The flow of 1855 covered 15,000 

 acres and represented a discharge of six hundred million cubic yards of basalt. 

 The flow of 1880-81 covered 20,000 acres and equalled at least five hundred and 

 forty million cubic yards of lava. These estimates are necessai-ily suggestive 

 rather than accurate. When we look at the mountain as a whoh' we see numer- 

 ous streams of similar proportions showing plainly on its surface. Looking 

 deeper we find it made up of countless thousands of similar streams and con- 

 clude that at the present rate of gi'owth millions of \-eai's lia\c elapsul since 

 the building of the mountain first ])egan. 



Work ok Hawaii's Volcanoes. 



It should be observed that during the period of more than one hundred 

 years that Mauna Loa and the volcanoes of Hawaii have been under obsei'vation 



