Investigations and Writings of Baron Humboldt. 213 
mention made of a circumstance which is rich in consequences, 
and well deserving of notice. This is the assumed condition 
of greater density (of increased pressure) which is ascribed 
to the atmosphere, at early periods of the formation of the 
earth. It is certainly not improbable, that the atmosphere, like 
the water, was at early periods loaded with a quantity of 
foreign substances,which, by the action of volcanos, ascended in 
their vapours at ahigh temperature, and were afterwards sepa- 
rated from them, just as partially takes place on a small scale 
at the present day, in volcanic eruptions. The greater heat thus 
produced in the solution, and the greater elasticity of the par- 
ticles caused by increase of pressure, must necessarily have in- 
creased the dissolving power of the general body of water; and it 
may thus be naturally explained how the water, at early periods 
of the earth’s history, could contain a large quantity of matters 
dissolved, whichat the present time are, it is true, still contained 
in it, though in very small quantity. This circumstance is of 
great consequence in the explanation of many details, which we 
must here pass over ; but it affects, on the great scale, not only 
the quantity of lime formerly dissolved in such large quantity 
in the water, but perhaps still more the silica which at certain 
places has been precipitated in large quantity from a chemical 
solution. On this point we find a remarkable example in the 
springs of the Geysers, in Iceland, where, at a high tempera- 
ture, and under increased pressure, the water is able to take 
up a much larger quantity of silica than it can under ordinary 
circumstances. Lastly, we know that, under high pressure, 
not only gaseous bodies can be converted into liquid ones, but 
also that water can absorb large quantities of gaseous bodies. 
But we have here, at the same time,a mode of explaining the 
altered chemical action of many bodies on each other, and the 
possibility of the union of these in the earlier conditions of the 
earth, which could not occur under the present general state 
of matters, but which are by no means in opposition to the 
laws of nature. Hence many of the most distinguished natu- 
ralists have adopted this view of the increased atmospheric 
pressure, accompanied by elevation of temperatue, which ex- 
isted at early periods, and it has more especially attracted the 
notice of Mitscherlich. 
