On Volcanos and Earthquakes. 1 



great celerity ; let us collect the air thus disengaged, and we 

 shall find its quantity a little above four per cent, in bulk of 

 the water under experiment. 



The water of the sea, always under full atmospheric pres- 

 sure, is constantly agitated by the wind, and, being divided, 

 at its surface into waves and breakers, it so multiphes its 

 points of contact with the atmospheric air, that it, of course, 

 absorbs all that its affinity for it, under these circumstances, 

 allows. Moreover, all rain water being divided into drops, 

 the most favorable condition for its combination, brings down 

 water perfectly saturated with air, and the whole quantity of 

 rain that falls on the globe goes ultimately to the sea, wheth- 

 er it falls directly into it, or whether it is carried to it by rivers 

 flowing down and renewing constantly their surfaces, all 

 which circumstances unite to supply the sea with a new 

 and perpetual addition of combined atmospheric air ; it may 

 then be admitted that the sea water is completely saturated 

 with this fluid. 



We have seen, in one of the preceding paragraphs, that 

 the affinity of the air for water is very weak. Is it a chemi- 

 cal combination, or merely an affinity of cohesion ? It mat- 

 ters not which opinion we form in that respect, for true it is, 

 that the least change in the temperature, or in the relative 

 densities, destroys their union. We have just seen that in 

 spring water, by the mere subtraction of the atmospheric 

 pressure, the air resumes its gaseous form, and then, from its 

 relative levity, separates from the water, and ascends and 

 breaks into bubbles at its surface. Now, below the depth of 

 twenty-five thousand six hundred feet, the air is denser than 

 the water ; and if a density different from that of the water in 

 minus has been sufficient to operate their disunion, a similar 

 difference in plus must produce the same effect. A bubble 

 of air, under the pressure of eight hundred atmospheres, 

 small as we may conceive it, is still a bubble of air, and its 

 density being superior to that of the medium in which it is 

 placed, it must plunge to the bottom, performing exactly 

 what we have ascertained to be the case with the bell. I 

 conceive that these bubbles collect together in sinking, just 

 as they do in rising, making a constant shower at the bottom 

 of the sea, to supply the constant consumption of it, as we 

 shall soon have occasion to state. 



Until this moment we have called the air absorbed by wa- 

 ter atmospheric air ; which, according to the multiplied ex- 



