172 F. D. ADAMS EXPERIMENT IN GEOLOGY 



Doctor Lister, entitled "On the cause of earthquakes and volcanoes/' 

 which appeared in Volume 11, published in 1705, the author presents a 

 most interesting discussion of these phenomena concerning which we are 

 still speculating, not, however, it is to be hoped, without making some 

 very substantial advances toward their true solution. "I have elsewhere 

 shown," says Doctor Lister, "that the breath of pyrites is sulphur ex iota 

 substantia. Again, that the material which is the cause of thunder and 

 lightning and of earthquakes is one and the same, namely, the inflamma- 

 ble breath of pyrites, the difference being that one is fired in the air and 

 the other underground." He then goes on to give his reasons, which time 

 will not permit us here to reproduce, but which are most ingenious, and 

 then continues : "We with great probability believe volcanoes to be moun- 

 tains made in great part of pyrites by the great quantities of sulphur 

 therein sublimed and the application of the lodestone to the ejected 

 cinder." He considers that the mountains were probably "kindled shortly 

 after creation" and by the spontaneous ignition of this mineral. 



Iron pyrites giving off sulphur, as it does when heated, was looked on 

 askance, as in some way connected with diabolical manifestations in 

 nature. The author of "A Theory and History of Earthquakes," pub- 

 lished in London in 1753, writes: 



"This dreadful mineral is found in England as well as in other places more 

 subject to earthquakes, but in smaller quantities and generally containing less 

 of the sulphur, and this may be a principal reason why our earthquakes have 

 been hitherto very slight and comparatively few." 



This relation of volcanic phenomena to sulphurous minerals had fur- 

 ther support in the general opinion coming down through the centuries 

 from the time of the Greeks, or even earlier, that the center of the earth 

 was a place of everlasting fire, serving, as one ancient writer puts it, as 

 "an eternal jakes or prison, destined for the punishment of the damned." 

 The brimstone always associated in the popular mind with this place of 

 plutonic punishment related itself admirably to the sulphurous exhala- 

 tions from craters at the surface and to the occurrence of pyrites in the 

 intervening strata, although the conception gave rise at times to certain 

 curious intellectual difficulties. 



Thus, in referring to the vent at Vulcano, in the Phlegrean Fields, the 

 writer just quoted asks : 



"If this be hell, what a desperate end made that unhappy German who not 

 long since slipped into these furnaces, or what had his poor horse committed 

 that fell in with lijm that he should be damned, or at least retained, in purga- 

 tory?" 



