THE 



AMERICAN JOURNALOFSCIENCE 



[FOURTH SERIES.] 



Art. XXYIII. — Effects in Mokuaweoweo of the Eruption of 

 191b; by Harry O. Wood. 



Mokuaweoweo is the summit crater of Manna Loa, the 

 great volcano on Hawaii. It is a large depression, produced 

 by collapse, in the broad, summit plateau which terminates the 

 grand dome of the mountain. It is not much visited. 



Eruption began in this crater shortly after noon on Novem- 

 ber 25, 1914. It undoubtedly continued until January 11, 

 1915, — for rising fumes illumined at night could be seen from 

 the Hawaiian Volcano Observatory, at Kilauea, as late as 

 January 10. The Observatory is situated almost due east from 

 the crater at a distance of about 22 miles (about 35 kilometers), 

 and it is at an elevation about 9700 feet (2900 meters) nearer 

 the level of the sea. No symptoms of eruption were observed 

 later than January 11, 1915. 



Under the auspices of the Hawaiian A r olcano Observatory 

 the writer has made three expeditions to Mokuaweoweo. 



In 1913 he first visited it in company with Mr. J. W. Green 

 of the U. S. C. & G. S., when nearly four complete days were 

 spent there at an elevation slightly in excess of 13,000 feet 

 (4000 meters). On that occasion camp was made at about 10 

 a. m. on Sept. 30, and broken early in the morning of October 

 4:, 1913. It was located on the summit level at a point on the 

 southeast margin of the crater close to the edge of the cliff. 

 Its approximate site is shown on the maps accompanying. 



On this expedition the writer spent one day in walking com- 

 pletely around the crater margin on the summit plateau, — a 

 distance of 12 to 14 miles : another day in a hurried explora- 

 tion of the eastern plateau region ; and a third in traversing 

 the southern and central part of the crater floor and a large 



Am. Jour. Sci. — Fourth Series, Vol. XLI, No. 245. — May, 1916. 



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