Ke LPAWUSE AY EAD WATT T: 195 
and besides, a confined space or throat above gives far greater pro- 
jectile power to the imprisoned vapours, causing, as a necessary 
consequence, loud reports and often a trembling of the cone at 
each explosion. In this manner the fragments of lava at Vesuvius, 
Stromboli, and elsewhere, are thrown to so surprising a height, and 
the cinder summits of the volcanic cones are formed. ‘The Hawaiian 
volcano seems a tame exhibition compared with these vents, until 
we consider that its quiet is a consequence of its more vivid action. 
That the lavas are extremely liquid is obvious from many facts stated. 
The size of the jets is a direct measure of its fluidity :—the smallness 
of the drops tossed up; the slender cones and cylinders formed by 
accumulation; the quiet murmuring sound, “hardly drowning ordi- 
nary conversation,” even close alongside of an active lake of lavas, 
344 acres in area; and the resemblance of the whole process to 
simple ebullition,—all betoken extraordinary liquidity in the molten 
rock. And even in its most violent moods there is but a more active 
condition of the same process. We are struck with the expressions 
Captain Kelly uses in describing the sounds, at a time when there was 
remarkable violence :—“ Hissing, rumbling, agonizing sounds;” and 
again, on another day in the pit, “large volumes of steam, hissing 
and cracking as it escaped.”* Without attributing perfect accuracy 
to the account of a scene so terrific as almost to force the mind, not 
especially guarded, to exaggeration in describing it, we learn from 
the statements at least that ‘deafening thunders” are rarely sounded 
through Pele’s realms. Instead of the viscidity which compels the 
vapours to accumulate before they can force their way through, the 
little bubbles are rising freely and bursting over the whole surface. 
There are pools of small size—narrow vents—yet the action in them 
is the same, except occasionally, when the lavas are stiffened and 
rendered more viscid by partial cooling, bubbles of larger size rise 
and explode with some noise.. ‘This peculiar character of Kilauea is 
one of great geological importance, and will be farther dwelt upon in 
our final conclusions on volcanic agencies. 
Il. The quiet mode of eruption.—In the several cases of eruption of 
which we have any definite account, the process has been the same in 
its progress and results as detailed on the preceding pages. The boil- 
ing pools of the lower pit have gradually filled this part of the crater 
by their overflowings, each stream cooling, and then, in a few hours or 
days, followed by another and another overflow in different parts of 
* American Journal of Science, xl. 119, 121. 
