274 HAWAIIAN ISLANDS. 
an earthy margin around the shallow cup-shaped cavity. The rock 
crops out in one place, and shows the same features as above de- 
scribed. Ejected cinders probably covered the lavas, as in other in- 
stances; the red colour is the result of decomposition setting free the 
iron in the state of red oxyd. 
d. In number A, the larger crater of the summit is nearly two hun- 
dred feet across. ‘The same red earth characterizes it inside and out. 
The smaller crater les adjoining, and is forty feet across and twelve 
deep. The walls around consist of cellular lava in layers which 
appear to have flowed from the larger crater; the rock is the same as 
that of the plains below. On one side of this small crater there is an 
entrance to a cavern which appeared to run down the hill: it could 
not be traced beyond thirty feet, on account of the rocks that had fallen 
in from above. The entrance is eight feet high and fifteen wide, and 
the walls are, in part, incrusted with lava stalactites. The cavity 
appears to indicate that a stream of lava had flowed from the small 
crater. ‘There is still another depression on the western slope of this 
volcanic hill, that may have been a third crater. 
e. To the eastward of the Old Crater, about three-fourths of a mile, 
there is a small hill (E), with evenly rounded top, as represented in 
the foreground of the preceding sketch. It has a shallow cavity, 
about ene hundred feet in diameter, broken down on one side, with 
walls of semi-columnar lava on the other. The lava is lamellar in 
structure, like that of the Old Crater, and the surface is covered with 
ropy and twisted slag-like scoria. This is the last of the eight craters. 
There is another small elevation near the Old Crater, about one hun- 
dred feet across, and twenty high, which formerly may have had an 
opening, though now there is no satisfactory evidence of it. It is 
covered with blocks of lava like the plain adjoining. 
The lavas of the Koloa district probably issued from some or all of 
these craters, and from fissures in the plain. All the hills but E, lie 
nearly in the same line; and, probably, a large fissure was opened in 
the direction of this line, from which the eruptions took place, certain 
points along the fissure becoming vents for continued eruption and 
giving origin to the cones,—the usual mode of action on Hawaii and in 
other volcanic regions. In the Old Crater, the lavas appear to have 
boiled up to the top, and thus formed the crest, as a ridge is formed 
around a lake in Kilauea, and then subsided again, leaving the sides 
covered with pendent masses of scoria. 
The red soil of the Koloa district resembles that in other parts of the 
