502 A NATURALIST ON THE " CHALLENGER." 



churning up of the lava was more violent. It occurred here 

 also as in the other pond, at the bases of the low bounding cliffs 

 only. The waves clashed against the cliffs, threw their spray 

 high into the air above them, and the wind carried part of this 

 spray over the edges of the cliffs, so as to fall on the hard lava 

 platform above. 



The spray masses, cooling as they fell, formed in their track 

 the threads known as " Pele's hair," like fine-spun green glass. 

 Many of the threads could be picked up, each with the small 

 mass of hardened lava still attached. These fallen masses are 

 closely like drops thrown out of a pitch-pot. Some were nearly 

 pear-shaped. Others, which had reached the ground before 

 setting, or when only partially set, had coiled up into various 

 forms as they fell, but nearly all showed an upright fine point, 

 where a hair had been attached to them. 



Pele's hair, thus formed, drifts away with the wind and hangs 

 in felted masses about the rocks, and the birds sometimes gather 

 it, and make their nests entirely of it. 



Between the two ponds was a lava fountain, the one which 

 had been seen playing the night before, but was now quiet. A 

 lava fountain is a tall hollow cone ; an extinguisher as it were, 

 with a hole at the summit, which is built up of successive 

 jets of lava thrown out of a hole, and hardened one over the 

 other. 



The surface of the cone looks as if built up of small masses 

 of pitch thrown on to it hap-hazard one over another. 



As the mouth of the cone contracts, the jet is thrown higher 

 and higher, and the spray falling all around, covers the lava 

 platform around with congealed drops of a lava rain, as it were. 

 Each of these drops forms, like the spray from the waves, a Pele's 

 hair.* 



Over one of the ranges of low cliffs in the crater, a cascade 

 of lava had poured, and cooling and setting as it flowed, had 

 been drawn out into long ropes and rounded ridges which were 

 twisted one over another, and formed a curiously gnarled and 



* Mr. H. C. Sorby, F.R.S., had come to the conclusion from the 

 observations on furnace slag that Pele's hair was probably formed in this 

 manner with globules attached. " Nature," Vol. XVI. 



