VOLCANIC ACTION, HAWAIL 225 
elongate form of Kilauea and others. We have in Kilauea a complete 
exemplification of this subject. When the lakes in this crater subside 
one or two hundred feet, as sometimes happens, they are actual pit- 
craters. The crater, Kilauea, it should be noted, is itself one-fourth as 
long as the whole line of pit-craters to the eastward, and the large lake 
within it is as broad as many of the pit-craters themselves. 
We may, therefore, believe that from Kilauea towards the east-south- 
east, at some period of eruption, there was opened a series of deep 
rents accompanied by ejections of lava, which drained Mount Loa as 
now lower openings drain off the lavas of Kilauea. At certain points the 
lava continued in active ebullition, and perhaps for a while flowed over. 
Kilauea stands at the intersection between the line of fissures here 
pointed out, and another line extending to the southwest; and while 
its own length has the direction of the latter, the many pit-craters are 
in the former. The two were probably, therefore, of simultaneous 
origin ; and the rending of Mount Loa, which opened this vast gulf and 
the other vents, consisted in the starting of a great triangular seg- 
ment of the dome. It must have been a deep rent, different from any 
ordinary eruption, to have opened a perpetual fountain of boiling lavas 
—a fissure that reached down to the source of the central fires of the 
dome; the starting, therefore, of such a segment, is not only a proba- 
ble result, but may be considered as almost a necessary one. ‘The 
island of Maui will afford us an example of a like result, established 
by facts which cannot be doubted. We have before remarked that 
Kilauea is nearly in the line of the Loa range of heights in the group, 
and constitutes the southeast extremity of this long northwest and 
southeast chain. We observe, moreover, that its longer diameter and 
the southwest fissure correspond in direction to the transverse trend 
pointed out, in which he the two summits Kea and Loa, and the two 
islands at the west end of the group, Niuhau and Kauai. 
Kilauea, when first opened, may have been occupied with lavas to 
its summit; and for a while they may have overflowed. The natives 
have a tradition to this effect; and the slight elevation of the plain 
about it seems to support it. But subsequently, an opening in the 
mountain’s sides below emptied it of its lavas, as well also as the 
smaller pits. After this, Kilauea boiled and steamed away at a lower 
level, and was the only vent that remained in action. 
In another place we have observed that the fires of the Hawaiian 
Islands have become extinct seriately from the northwest towards the 
southeast ; and in this transfer of a large part of the force of Mount Loa 
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