ITS FIRST APPEARANCE. 257 



of sixty feet ; and discharged volumes of sulphur- 

 ous smoke. The elevated mass, as there is no 

 action of the atmosphere mentioned, that could 

 sustain a column of water to that height, must 

 have been steam. That steam, however, from 

 the supply of a whole sea of cold water, and the 

 powerful action of the fire under it, may have 

 had the colour and apparent density of a mass of 

 water. Indeed the external part of it must have 

 been condensed, and descending in a thick fog, 

 which fog would be kept from spreading on the 

 surface of the sea, by the wind which must have 

 set toward it in all directions, to supply the air 

 which was constantly rarifying and ascending over 

 it. The smoke mentioned by the Sicilian cap- 

 tain, was, most probably, the hottest part of the 

 steam, because if the heated strata had so broken 

 under water, as to allow volumes of real smoke 

 to escape, the solid matters would not likely have 

 reached the surface. It appears from the obser- 

 vations made by other vessels, that the immediate 

 bottom was mud, and that the depth, after the 

 island was formed, was one hundred and thirty 

 fathoms, at the distance of one mile. That was 

 nearly three hundred and thirty-eight pounds (say 

 three hundred weight) on the inch, from the mere 

 pressure of the water, without taking into the 

 account the condensation, the weight of the mud, 

 and the resistance of the strata, which there are 

 no means of ascertaining ; but they, in all proba- 

 bility, exceeded the simple pressure of the water. 



Now, if we suppose that the surface, acted 



under by the heat, was only a circle of about 



one hundred and twenty fathoms in diameter, we 



shall form a rude estimate of the power employed. 



z 3 



