314: SGientific Intelligence. 



He holds that the general cause of death and destruction was a 

 blast of steam charged with hot dust, which passed through the 

 city with hurricane force, and that gases, probably in part inflam- 

 mable, were present, but played only a secondary part in the dis- 

 aster. 



Most of Russell's report is devoted to St. Vincent. He holds 

 that the destruction on this island was due to dust, lapilli and 

 stones which fell on the land while yet hot ; but that a hurricane 

 blast of steam charged with burning dust did not sweep down 

 from La Soufriere as it did from Mt. Pelee. The area of devasta- 

 tion on St. Vincent was much greater than on Martinique. Atten- 

 tion is called to the violent secondary or superficial eruptions due 

 to rain or river water coming into contact with the still heated 

 interior of the great deposits of recent ash in- the gorges of the 

 Wallibou and Dry Rivers ; to the pulsating flow of the Wallibou 

 river due to overloading by volcanic sand ; to the canyon-like 

 dendritic drainage forms already produced in the coating of fresh 

 dust and lapilli by the rains ; and to the fact that houses standing 

 on the windward (east) slope of the volcano had suffered most 

 on the sides farthest from the crater. 



Five miles from the crater Russell found the level fields coated 

 with a layer of new volcanic debris about two feet thick. This 

 would be a minimum measure and the average thickness of the 

 deposit would be several times as great. The greater part of the 

 debris consists of gray scoriaceous andesite and came from the 

 columns of fresh lava that rose in the conduit of La Soufriere. 

 This material was suflSciently cooled to become solid before it was 

 blown into the air, and to a great extent was reduced to dust by 

 the sudden expansion of the steam it contained. In addition to 

 the fraofments of fresh lava the fields were strewn with angular 

 masses of older and much more compact lavas torn from the 

 throat of the volcano. 



Diller describes the older lavas of Martinique, collected by 

 Hill, as being hypersthene andesite, hornblende-hypersthene ande- 

 site, hornblende andesite and dacite (quartz andesite), and the 

 products of the May eruption of Mt. Pelee as belonging to the 

 hypersthene-andesite class. He says that the specimens from St. 

 Vincent are of hypersthene andesites, remarkable for their con- 

 tent of olivine. 



Hillebrand concludes that, while the ejecta from the two vol- 

 canoes are of the same general type, and while the material from 

 the same vent may vary in composition within limits, according 

 as it is collected near to or far from the vent, and in coherent or 

 finely divided form, yet there are characteristic differences by 

 which it appears easy to distinguish the product of one volcano 

 from that of the other. Diller's report is accompanied by seven 

 analyses of pumice, sand and dust from these eruptions and 

 Hillebrand's discussion by three such analyses. e. o. h. 



2. The Report of the Geological Survey of Louisiana : G. D. 

 Harris, A. C. Veatch, J. Pacheco. — The papers contained in 



