Real and supposed effects of igneous action. 347 



tal strata vary from a few inches to hundreds of feet in thick- 

 ness ; next above one of these strata is seen a space from 

 one to ten feet wide, or high, that appears to have been in a 

 state of fusion long after the mass above and below had be- 

 come consolidated, in which forms it may be seen alternate- 

 ly for hundreds of teet high, shewing caverns and fissures of 

 all forms and sizes ; some not unlike a common oven exter- 

 nally, but much more spacious within, many of which were 

 formerly used as repositories for the dead, especially when 

 they were difficult of access. The volcano, of which I have 

 made frequent mention, was measured by a surveyor of lord 

 Byron's, and estimated to be nine hundred and thirty-two 

 feet down to the black ledge, and four hundred more down 

 to the bottom ; in all, thirteen hundred and thirty-two feet, 

 so that you may form some judgment of the dimensions of 

 the crater ; the depth of a place that we supposed, on our 

 first visit there, to be four hundred feet, is found, by meas- 

 urement, to be nine hundred and thirty-two. Many times 

 have I wished that you could accompany me to that won- 

 derful scene." 



Remarks on the specimens transmitted by Mr. Goodrich. 



They contain most of the usual volcanic products, and are 

 remarkably interesting. 



1. Sulphur, of all the shades between white and yellow ; 

 the more delicate specimens, mentioned as being in the cocoa- 

 nut shells, are pieces of sulphur. In the collection are nu- 

 merous crystals of sulphur, more remarkable for delicacy and 

 richness of color, and finish of form, than for size. The sul- 

 phur is found also investing or penetrating the proper lava. 



2. Siliceous sinter, white, porous, light, tasteless, harsh to 

 the touch, readily scratches glass — resembles that of Ireland 

 and the Azores. Mr. Goodrich remarks, that the white spe- 

 cimens are from the bottom of the crater ; if he means these, 

 as he probably does, may we not presume that the silex, dis- 

 solved in water, probably containing alkali, and heated in- 

 tensely under great pressure, was liberated when the wa- 

 ter was rapidly evaporated, and thus the silex was deposited 

 in a spongy form, as the steam and gases made their way 

 through it. 



