Am. Jour. Sci., Vol. XXXVII, Jan., 1914. 



Plate IV. 



VOLCANO VOLATILE AND AERIAL 



I a. i. Burning gases -true flames, a rranspan 



/SSUVIUS / j I'- Opaque vapor cl..', I ' 



~~ s i 2 . Light explosive effects - puffs, rings. ' 



' |i. Strong explosive effects — aerial concu! 



Apr . 8,'?o6. 

 3.30 A.M. 



6 The ash « pino >.. Slioi 

 I. Large angular block 



ers or as 



& bowld 



h. 



c. i. Pisolites. 



2. Mud sh 



Dwers. 





a. Volcanic lighlu 



II. Linen 

 % \2.Globe 



rflashrs 

 S.Slellai 







b. Detonation 



Sharp crackle. 

 Heavy thunder. 



i 



c.Silent discharge 



-St Elmc 



■s Fu e 



\ 



Fumaroles - primary type 



{developed on volcanic channels). \A 

 Fumaroles — secondary type 



(.on entpled lava or clastic ejecta) 

 Flame-emitting rumaroles. 



DIAGRAM CHART \, 

 (Perrel system) ■ 



of Volcanic Activity 

 {Physical) 



VOLCAN 



:an0 VOLATILE A\D AERIAL 



J a. 1. Rurnitig gases— true flames. 2 Transparent hluisl 



U V I II ^ X hi'- Opaque vapor cioud - the white « panache ». 



V V ' " / °-\2. Light explosne effects - puffs, tings. >orltces. 



f 1. c-....~ ..i**,-:..« -fl - -..,.. ...—.-.i nnnn ..^^r nn 



DATE 



APR. <f, IJOie.. 



3-00 P.m. 



a. Dark jets, volutes, spear-head projecti 

 (chaotic ejeclamenta — cone debris) 

 6. The ash «pino... Showers of ash 

 I. Large angular blocks & bowlde 

 c. 1. Pisolites. 2. Mud showers. 



j Volcanicli»htnine ;i ' Z -"*"" vf ' lM " 

 6 \2. Globe 3. Stella) 



"^nation {J; %£?£ &. 



:. Silent discharge — St Eimo's Fire. 





pnt 



ry type 



(developed on volca 

 Fumaroles — secondary type 



(on entpted lava or cla-tic ejecta') 

 Flame-emitling fumaroles 



U,kAM CHART 



\ 



subsidence, collapse. 

 3. Subsurface 



Hot ash -flows <2f d>y avalanche. 



Intcrcratertc slides 3. Mud i 

 Landslides of volcanic causation 



/ OBSEKVER 



?£R-RBT, 



