114 Proceedings of the Royal Society 
The island of Hawaii, or the most recent and easterly, is composed 
of four mountains — the Mauna Kea, 14,500; Mauna Loa, 13,800, 
Huallalei, 8000, and Kohala, about 5000 feet in height, with large 
valleys of 2000, 3000, to 6000 feet above the sea-level between. 
The slope of the mountains is usually gentle, and numerous small 
craters of 100 to 300 feet in height are found distributed on their 
sides, and also in the intermediate valleys. On the west side pre- 
cipitous rocks face the sea, with a height of 3000 feet, which have 
valleys opening seawards that are almost inaccessible from the land 
side, owing to the precipitous character of their sides. It is on 
this island that the most recent displays of volcanic activity are 
seen, the country having been overrun in many places by lava 
flows, which have left large tracks quite useless for agricultural 
purposes. Earthquakes are common, and the summit crater of 
Mauna Loa, 13,800 feet up, is frequently, and that of Killauea (on a 
level plateau on the side of Mauna Loa, about 3000 feet above the 
sea) is almost always in a state of activity. The crater of 
Killauea is on the north-east of Hawaii, about 32 miles from the 
bay of Hilo, which is the most convenient starting-point for those 
wishing to visit the volcano. In the ride of 32 miles one has 
an ascent of some 3000 feet, but the ups and downs are so numerous 
that one can hardly detect it. During some portion of the way 
one passes through very dense tropical vegetation, palms, tree 
ferns, &c., with creepers and ferns clustering around, but for the 
most part the path lies over lava flows, so recent as to be almost 
devoid of vegetation, which render it so rugged as to compel one 
to walk his horse the greater part of the way. When approaching 
the volcano the visitor is at first struck by the sight of hundreds of 
steam jets rushing up in all directions, some of which are utilised 
as vapour baths, by putting a wooden box over them with a hole 
in the top large enough to admit the neck of the bather. On going 
some hundred yards further, an immense pit appears, at the further 
end of which during the day are seen large volumes of smoke, 
while at night a red flare is visible in the sky, with an occasional 
piece of white hot lava getting tossed up high enough to be seen 
above the edge of the inner crater. This large pit or outer crater 
is of oval shape, and some 3 miles long by 1^ to mile broad in 
the widest part. The sides are precipitous, and from 600 to 700 
