July 30, 1915] 



SCIENCE 



153 



of the splashing caves have heen on the west 

 and south sides, with streaming in these 

 directions. 



The northwest pool appeared on March 7, 

 owing to a collapse of a portion of the crust 

 on which there had been spatter cones. The 

 pool was 25 X 40 feet. The next day the pond 

 was larger, and on the 9th still larger. South- 

 east of the pool there was a small orifice throw- 

 ing drops of molten lava YO feet in the air. 

 The lava in this orifice was several feet lower 

 than the level of the pond, although but a few 

 feet away. The pool was fountaining quietly 

 until the crust suddenly broke up and was 

 swept in the north end. On the 15th, this 

 pond had increased in size until it was 270 

 feet long (north-south), and 100 feet wide. All 

 the fumaroles had coUapsed into the pond. 

 The pool was quiet with three splashing caves 

 until suddenly a violent streaming from the 

 south end to the northeast end developed, and 

 three minutes later the 1914 shelf above the 

 place of inflow collapsed. The north end of 

 the pond was filled with talus, and the re- 

 mainder became quiet. 



The main lake on March 15 was found to 

 have increased in size by a collapse, on the 

 south side, of a creseentic area 150 feet long 

 and 30 feet wide in the center. The length of 

 the lake from northwest to southeast was 500 

 feet, the width at the center 150 feet, the depth 

 480 feet— 35 feet below the 1915 ledge. On the 

 southeast, a small pond had developed by the 

 appearance of a ledge across the southeast arm 

 of the lake. This pond was splashing vio- 

 lently. The next day the lava from the main 

 lake was pouring into it under a natural 

 bridge, and rushing at a rate of 6 miles an 

 hour under the 1914 shelf on tbe south. On 

 the 19th, this current was still rushing into 

 the small pond, and the level of the lake had 

 dropped. The northwest pond had also 

 dropped, leaving a circular shelf and a black 

 ledge. 



Mauna Loa broke out, with great lava foun- 

 tains in the crater Mokuaweoweo, between 

 noon and one o'clock on November 25, 1914, as 

 described by Professor T. A. Jaggar, Jr.^ On 



2 Amer. Jour. Sei., Vol. 39, 1915, pp. 167-172. 



the 28th, the party which reached the summit 

 observed a long fountaining pool on the south 

 side of the Mokuaweoweo basin, with over- 

 flows on the floor. There were eight main 

 fountains and a sheet fountain on the south, 

 playing continuously to heights of 300 to 400 

 feet. On December 4, only four fountains were 

 seen, the northernmost being the larger. 



The fume column on the first night was of 

 the pine-tree form, being composed of from 4 

 to 6 wavy strands. On the second night the 

 column was estimated by Mr. H. O. Wood to 

 have a height of 6,000 to 7,000 feet. On the 

 first of December, a slender, straight fume 

 column was seen, faintly illuminated, and ris- 

 ing to a height of 9,000 feet or more. From 

 December 7 until the evening of the 10th, no 

 trace of a fume column was seen from Kilauea. 

 An evening glow and fume cloud, and occa- 

 sionally fumes by day, were visible on clear 

 days during the remainder of December, and 

 until January 11, when both glow and fume 

 cloud disappeared together. The greatest 

 fume column in December was after Christ- 

 mas, and the final diminution in volume oc- 

 curred during the last week. 



The Volcano Observatory expedition reached 

 the summit on December 15. In the south- 

 west part of the crater a large red fountain 

 was playing continually to a height of 100 

 feet and occasionally to a height of 150 feet. 

 The fountain was at the northeast corner of a 

 pool of crusted pumiceous lava, and in front of 

 a portion of a cone 75 feet high of its own 

 construction. On the west side of the lake 

 there were lower fountains, and still other 

 fountains broke through the crust of the pool 

 at different times. The character of the foun- 

 tains, with jets forming fragments which 

 floated away, suggested a very gaseous, light 

 liquid. No changes in the walls or pits of 

 Mokuaweoweo were observed. 



The activity of these volcanoes in the imme- 

 diate future is difficult to predict because of 

 the scarcity of detailed information concern- 

 ing them previous to 1911. A general response 

 of the lava to earth tides has already been 

 shown by Mr. F. A. Ferret, and the summary 

 given above shows that the lava in Kilauea 



