250 K. T. HILL — PELE AND THE WINDWARD AKCHIPELAGO 



until it reached, perhaps, 1 mile high and 2 broad. After this it ceased to enlarge 

 and gradually lost its dense blackness through ash settling down and leaving noth- 

 ing but white steam. " 



The final stage of the work of the volcano has probably been reached 

 recently. It was just the reverse of the foregoing events. The force of 

 the ascending magma decreased, the eruptions gradually diminished in 

 intensity and frequency, the vents became clogged by cooling lava, and 

 gradually the orifice closed, although the smouldering magma may con- 

 tinue to push dikes here and there into the/oundations of the self-made 

 ash pile. 



Until some future period, when another cycle of explosive eruptions 

 will reopen it, Pel6, with its lid again on, will be considered an extinct 

 volcano, and humanity may again inhabit the outer slopes of its chim- 

 ney. But the real volcano within, banked up with its own debris, is 

 potentially as active as it has always been as far back in time as the 

 human mind can reach.* 



PRODUCTS OF THE ERUPTIONS 



Rock 'products. — The visible ejecta from the vent of Pele have been frag- 

 ments of rock material, mostly in a finely divided condition, water, and 

 gases of a nature not fully interpreted, which are further discussed in 

 this paper. 



The rock products of the volcano were the debris of an ascending, 

 cooling liquid molten magma. This, exploding into fragments as it 

 approached the vent, manifested itself in the forms, mostly of lapilli, 

 sometimes called ash and sometimes sand ; boulders of pumice, pseudo 

 bombs, mud, and sometimes the debris of the old conduits. The various 

 forms of rock material were all composed of the mineralogical mixture 

 known as hypersthene-hornblende-andesite, embracing combinations of 

 many elements.")" 



Water products. — The large quantity of water accompanying the earlier 

 eruptions of Pele and great clouds of watery vapors were noticeable 



* The writer and other earlier reporters on the scene submitted evidence that the volcano in its 

 second or catastrophal stage had more than one vent, notably one to the west of the crater in the 

 gorge of the Riviere Blanche and the other to the east of the gorge of La Felisse, as noted by 

 Kennan and Heilprin. 



Concerning the existence of the western lateral vent, it was clearly stated, however (Century 

 Magazine, September, 1902, page 775), that "much is desirable to be known about this canyon, its 

 vent, and the condition of its bottom." 



The writer was perhaps erroneous in calling this supposed vent of the Riviere Blanche a crater, 

 for its existence was founded on testimony which can now neither be proved nor disproved, and 

 the question of its existence or non-existence is but a minor detail in the larger story we are 

 trying to tell. 



fAndesite is a technical term for a volcanic rock intermediate between those which are basic or 

 containing less than 50 per cent of silica and those which are extremely siliceous. In general, 

 they consist approximately of 62 per cent of silica (Si0 2 ). 



