Januaet 5, 1906.] 



SCIENCE. 



29 



for this solvent in a highly heated condition 

 and at the necessary depths within the 

 earth. Both from its parent mass and 

 from the overlying rocks traversed by it, i't 

 may take the metals and gangue. 



In the iipward and especially in the clos- 

 ing journey, meteoric waters may mingle 

 with the magmatie, and as temperatures 

 and pressures fall, the precipitation of dis- 

 solved burdens takes place and oiir ore- 

 bodies are believed to result. Gradually 

 the source of water and its store of energy 

 become exhausted; circulations die out and 

 the period of vein-formation, comparatively 

 brief, geologically speaking, closes. Sec- 

 ondary enrichment through the agency of 

 the meteoric waters alone remains to in- 

 fluence the character of the deposit of ore. 

 In brief, and so far as the process of forma- 

 tion of our veins in the western mining 

 districts is concerned, this is the conception 

 which has been gaining adherents year by 

 year and which, on the whole, most fully 

 accords with our observed geologic rela- 

 tions. It accords with them, I may add, 

 in several other important particulars upon 

 which I have not time to dwell. 



In closing I may state, that speculative 

 and uncertain as our solution of the prob- 

 lem pf the metalliferous veins may seem, 

 it yet is involved in a most important way, 

 with the practical opening of the veins and 

 with our anticipations for the future pro- 

 duction of the metals. Every intelligent 

 manager, superintendent or engineer must 

 plan the development work of his mine 

 with some conception of the way in which 

 his ore-body originated, and even if he 

 alternates or lets his mind play lightly from 

 waters meteoric to waters magmatic, over 

 this problem he must ponder. On its sci- 

 entific side and to an active and reflective 

 mind it is no drawback that the problem is 

 yet in some respects elusive and that its 

 solution is not yet a matter of mathematical 

 demonstration. In science the solved prob- 



lems lose their interest ; it is the undecided 

 ones that attract and call for all the re- 

 sources which the investigator can bring to 

 bear upon them. Among those problems 

 which are of great practical importance, 

 which enter in a far-reaching way into our 

 national life and which irresistibly rivet 

 the attention of the observer, there is none 

 with which the problem of the metalliferous 

 veins suffers by comparison. 



James Furman Kemp. 

 Columbia Univebsitt. 



SCIENTIFIC BOOKS. 

 The Tower of Pelee: New studies of the 



great volcano of Martinique. By Angelo 



Heilprin, F.E.G.S. Pp. 62-f23 plates. 



Philadelphia, J. B. Lippincott Company. 



1904. 



In the past three years a good deal of litera- 

 ture has appeared concerning the West Indian 

 eruptions of 1902. A part of this is a simple 

 record of observed facts. Perhaps a greater 

 portion is devoted to speculative inquiries into 

 the cause and nature of the eruptions and at- 

 tendant phenomena, especially those of Pelee, 

 whose remarkable characteristics have excited 

 the curiosity and interest of students in more 

 thali one branch of science. The solution of 

 many of the problems is rendered extremely 

 difficult through the lack of sufficient data 

 upon which to support hypotheses, and geolo- 

 gists often are compelled to admit that certain 

 of the problems must remain unsolved. It 

 has been impossible, in many cases, to obtain 

 much-needed information in the field in re- 

 gard to many obscure matters on account of 

 the continued activity of Pelee, and this must 

 be taken into consideration when an unusual 

 diversity of opinion appears in the views of 

 different observers. 



In the present work, which was published 

 nearly at the same time as Lacroix's report, 

 Professor Heilprin presents his views in re- 

 gard to the origin and nature of the tower of 

 Pelee. The book contains five short chapters, 

 in the first of which the author describes his 

 experiences and the impressions he received 

 on the occasion of his fourth ascent of Pelee, 



