218 HAWAIIAN ISLANDS. 
Ill. Isolation of the lines or conduits of volcanic action.—It is not a 
little surprising that summit eruptions should take place at an eleva- 
tion of 13,760 feet, when on the slopes of the dome, sixteen miles dis- 
tant, there is an open vent, Kilauea, three and a half miles in length, 
and more than 10,000 feet lower in elevation, showing no disturbance 
in its boiling pools, no signs whatever of sympathy. The conduits of 
the two vents must be separated to a great depth, in order that the 
force in the central one should accumulate to the amount of 2,500,000 
pounds to the square foot, when elevation to the level of Kilauea re- 
quires less than a fourth of this force.* If the two channels freely 
intercommunicated above the point of principal action in each, (or the 
place of origin of the vapours that constitute the lifting force,) they 
would act together: but in this great syphon, filled, as is believed, with 
molten rock, strange to say, the fluid stands 10,000 feet higher in one 
leg than in the other. 
We have remarked besides that the boiling pools in Kilauea move 
independently ; for one may sink fifty or a hundred feet while the 
other is boiling and overflowing. Moreover, as another example of the 
same principle, eruptions take place through the top of the walls of 
Kilauea, six hundred feet above its pools. ‘There is every reason to 
believe that Kilauea originated in the opening of a fissure to give exit 
to the lavas of Mount Loa; if so, we learn from these facts, that the lavas 
which filled the fissure between it and the summit and to a great 
depth within, have cooled, and made the mountain in this part as solid 
as before, leaving each conduit possibly as a separate branch of some 
deep-seated channel. In the same manner the smaller pools in 
Kilauea, though formed in a fissure that once radiated from an exist- 
ing lake, soon become distinct to a considerable distance down, owing 
to a closing of the intermediate vent by solid lavas. 
But is it possible that there is a free connexion between the legs of 
this great syphon? It is certainly difficult to conceive how in such a 
case the ordinary principles of hydrostatics could be so set aside. 
This, be it remembered, is no paroxysmal elevation of the lavas to the 
summit, but a slow and gradual result; and the difficulty therefore 
* As the bottom of Kilauea, at our visit, was 990 feet below the summit of the crater, it 
was only 2980 feet above the level of the sea, (the summit of Kilauea being 3970 feet,) 
which is about two-ninths of the whole height. In 1843, the bottom was somewhat higher, 
but could not have equalled @ fourth of the whole height of the crater. Even at the pre- 
sent period, with the lower pit filled to the black ledge, the height of the bottom is but 
3320 feet above the sea level, which is less than a fourth of 13,760 feet, the whole height. 
