30 



SCIENCE. 



[N. S. Vol. XXIII. No. 575. 



in June, 1903 ; the three following chapters are 

 devoted to observations upon the remarkable 

 tower of Pelee, and in chapter V. are ' some 

 thoughts on volcanic phenomena suggested by 

 the Antillean eruptions.' 



Stated very briefly, Pleilprin regards the 

 tower, or spine, whichhas appeared from time 

 to time above the summit, as ' the ancient 

 core of the volcano that had been forced from 

 the position of rest in which solidification had 

 left it' (p. 33). After presenting a number 

 of objections to Professor Lacroix's theory, he 

 says, on page 34: 



In assuming the tower to have been an ancient 

 neck-core which under enormous pressure had been 

 lifted from its moorings, we at least require no 

 condition that is not provided for by volcanoes. 

 There can be no objection to postulating the exist- 

 ence of such a core here, as in other volcanoes; 

 and if existing, there would seem to be no reason 

 why, under the gigantic force of Pelge's activity, 

 it should not have been dislodged and pushed 

 bodily outward. The reaction upon this con- 

 tained mass of accumulating heat, and the in- 

 fusion into it of steam and flows of new lava, 

 would help to explain the ' burnt-out ' and scraggy 

 look which from the first had been a characteristic 

 of the tower-rock. 



It is, perhaps, unfair to compare this work 

 with the report of Professor Lacroix, who 

 devoted more than six months to a study of 

 what might be termed the daily life of Pelee, 

 and who was aided by a corps of able assist- 

 ants, but one can not help being impressed 

 and possibly influenced by the abundance of 

 Lacroix's observations, the completeness of his 

 records, and the lucid exposition of his the- 

 ories; while, on the other hand, one hesitates 

 to agree with certain of Professor Heilprin's 

 views, not necessarily because they are new, 

 but for the reason that they are not supported 

 by sufficient evidence. Thus, in the statement 

 of his opinion concerning the nature of Pelee's 

 tower, he offers a number of somewhat the- 

 oretical objections to Lacroix's views and has 

 little more than suppositions upon which to 

 support his own hypotheses; in fact, he does 

 not take into account many of his own ob- 

 servations. Furthermore, there seems to be 

 some inconsistency in his arguments. After 

 stating that in Ms opinion the tower represents 



the old core of the volcano, he says, on page 

 34: 



It can not be doubted that the tower was vir- 

 tually solid to the core, and equally little need one 

 doubt that its temperature \\'as not such as to 

 maintain a fluidal or semi-fluidal interior. Had 

 the tower not been solid, or had it contained 

 much incandescent fluidal matter, the numerous 

 breakages, whether on the flanks or across the 

 summit, which marked the tower's history, would 

 have revealed these conditions many times. 



On page 18 the following occurs: 



On the other hand, that the tower was rifted 

 and had irregular passages through it, or through 

 parts of it, into which lava was at times in- 

 jected, is certain; and the members of the Lacroix 

 mission on more than one oeoasiou noticed areas, 

 and lines of incandescence in the basal portion 

 of the core, which they associated with flowing 

 lava-masses. On the night preceding my fourth 

 ascent of the volcano, June 12, 1903, the south- 

 west base of the tower was resplendently luminous, 

 made so either by actually rising lava or by a 

 partial remelting of that portion of the structure. 



On page 20, in referring to the first appear- 

 ance of the tower he says : 



Indeed, I remark in my report [' Mont Pelge and 

 the Tragedy of Martinique'], that it seemed to 

 me likely that the two glowing masses of fire 

 which shone from the summit, like red beacon- 

 lights, in the morning of. August 22, emanated 

 from the two (incandescent) horns that capped 

 the summit of the mountain. 



Although these statements are not flatly 

 contradictory, tibey at least leave a somewhat 

 hazy impression on the reader's mind. 



It will be difficult, even for those geologists 

 who hesitate to accept all of Lacroix's brilliant 

 reasoning and explanation in regard to the 

 physical manifestations of Pelee's eruptions, 

 to agree with Professor Heilprin's views, 

 largely because the manner in which they are 

 presented must in many cases fail to convince 

 the reader. 



In chapter IV. various observations on the 

 eruptions are summarized; among them are 

 references to the electro-magnetic disturb- 

 ances, propagation of sound- and shock-waves, 

 etc., together with more local phenomena. In 

 chapter V. the broad questions concerning the 

 cause of vulcanism in cases of such regional 



