jSt. Vincent, and Mt. Pelce^ Martinique. 343 



action along the lower portion of their courses, and much 

 steara, with or without large quantities of dust, has been 

 thrown high into the air when water has reached the heated 

 interior of the vast beds of volcanic ash deposited tliere during 

 this eruption. Mud-flows and torrents have been very numer- 

 ous down the gorges of these streams and on the plateau 

 between them. Some of these flows have come directly from 

 the crater, especially in the case of the Blanche; others have 

 originated on the exterior slopes of the old cone, while others 

 have started in the heavy ash-beds in the gorges in the manner 

 already described in connection with the Wallibou River, St. 

 Yincent, and the Falaise River on the eastern side of Mt. 

 Pelee. The surface of one of the mud-flows on the plateau 

 between the Seche and the Blanche is shown in flg. IT. Sub- 

 sequent rain has washed the fine mud from the stones. 



These streams of mud and stones present some characteris- 

 tics which distinguish them clearly from the surfaces of undis- 

 turbed ash-beds. The most striking of these is the existence 

 of curved folds or wrinkles transverse to the direction of flow 

 of the stream, the folds varying in size with the size of the 

 flow. The surface of an unmodified deposit of ash presents a 

 drifted appearance like that of a field of snow or of dry sand 

 on a sea beach, and the Richmond estate as illustrated in fig. 6 

 is a typical example. The plateau between the Des Peres and 

 Roxelane Rivers, on which was located the Fort Quarter of 

 St. Pierre, was covered w^ith several feet of wind-drifted ash, 

 and it was not a mud-flow or a series of mud flows which 

 destroyed this portion of the city, as has been stated in several 

 publications. 



In addition to the showers of dry dust and ashes, there fell 

 during the eruptions an immense amount of liquid mud which 



of the crater, where we obtained a view directly through the gorge lengthwise, 

 and repeated the examination from the crater rim on Jnne 26. We could 

 see no crater or center of eruption in the gorge of the Blanche below the 

 great crater, though there has been much secondary or superficial eruption 

 of steam from the ash-beds along the gorge. 



I cannot agree with the distribution of the "zones of devastation" 

 indicated on Hill's map or with the location of "mud craters" as the origin 

 of the mud-flows of the Seche, the Blanche, the Falaise and other valleys. 

 It is well to separate the devastation into zones of "annihilation" and 

 " singeing," in a general way, but the crater of the volcano should certainly 

 be included within the former instead of being placed outside of the latter, 

 as is done on Hill's map. The real location of the singe line of the May 

 eruptions is nearly that of Hill's " ash line " and is indicated approximately 

 on my map (p. 332), where it is called the limit of devastation. The "ash 

 line " should be placed at some undetermined distance far beyond the shores 

 of the island of Martinique. The existence of real "mud craters" on the 

 slopes of Mt. Pelee seems very improbable, for the reasons given on pages 

 337 and 338 and elsewhere in this article. The mud-torrents of the Grande 

 Riviere, which were among the heaviest of those experienced on the north 

 and northeast side of the island, are not indicated on Hill's map. 



