254 R. T. HILL — PELE AND THE WINDWARD ARCHIPELAGO 



vailing within the interior of the volcano- encrusted earth like those of 

 the sun. 



PELE'S CONTRIBUTION TO THE EARTH'S SURFACE 



The real work of Pele and volcanic work in general was the transfer 

 of enormous quantities of material from the great unknown reservoir of 

 the earth's interior to its outer crust, depositing layers of ashes over the 

 adjacent ocean, contributing gases and water to the atmosphere, and 

 adding greater height and mass to the preexisting land surface. Hence 

 from a world-making standpoint it was not destructive, but constructive 

 in its effects. Nothing was taken away from the surface of the earth, 

 nothing except life destroyed. Instead there is added numberless tons 

 of matter to that part of the earth alone known to man — its crust. Theo- 

 retically, this is the process by which the skin of our supposedly cooling 

 globe has been and is still being formed. In fact, all the known rocks 

 of the earth's crust may be traced back ultimately to igneous origin. It 

 is also the process by which islands have been built up above the ocean's 

 floor, the rocks of which, worn, dissolved, and redistributed in turn, have 

 become sediments of the ocean and the soils of the land. 



It would be interesting to be able to compute the actual work thus 

 accomplished by Pele's recent eruption by estimating the quantity of 

 rock, water, and gases which it actually transferred from the earth's 

 interior to its outer surface. Unfortunately, no record has been made 

 of the number of eruptions during the two years of activity, and hence 

 we can only convey an idea of the enormous total by an analysis. 



Professor I. C. Russell has estimated that each one of the clouds from 

 Pele discharged 40,000,000 cubic feet of solid matter, and that these dis- 

 charges taking place every five minutes were equivalent to 1,520,000,000 

 cubic feet per day. Heilprin states that this quantity is one and one- 

 half times that of the sediment which is discharged by the Mississippi 

 river in the course of a whole year, which is 812,500,000,000 pounds, 

 or a mass one square mile in area and 241 feet deep. 



Enormous as may appear the quantity of solid matter of each one of 

 these great volcanic clouds which have been projected into the atmos- 

 phere almost daily for over two years, it was but an insignificant frac- 

 tion of the total substance emitted for a greater quantity of material in 

 the shape of vapors and invisible gases passed out with each outbursting 

 cloud of ashes. 



It is impossible to estimate the vast volume of gases and water thus 

 contributed. Geologists like Dana and Geikie have estimated the pro- 

 portions of vapors and gases to solids to be in the ratio of 999 parts of 

 the former to one of the latter. 



