232 polykesiaK researches. 
into conical mounds, from six to twelve feet high„ 
which were, probably by the same power, rent into 
a number of pieces, from the apex to the base. 
The hollows between the mounds and long ridges 
were filled with volcanic sand, and fine particles oif 
olivine, or decomposed lava. 
This vast tract of lava resembled in appearance 
an inland sea, bounded by distant mountains 
Once it had certainly been in a fluid state, but 
appeared as if it had become suddenly petri¬ 
fied, or turned into a glassy stone, while its agi¬ 
tated billows were rolling to and fro. Not only 
were the large swells and hollows distinctly 
marked, but in many places the surface of these 
billows was covered by a smaller ripple, like that 
observed on the surface of the sea at the first 
springing up of a breeze, or the passing currents 
of air which produce what the sailors call a cat*s- 
paw. The billows may have been raised by the 
force which elevated the mounds or hills, but they 
look as if the whole mass, extending several miles, 
had, when in a state of perfect fusion, being agi¬ 
tated with a violent undulating or heaving motion. 
The sun had now risen in his strength, and his 
bright rays, reflected from the sparkling sand, and 
undulated surface of the vitreous lava, dazzled our 
sight, and caused considerable pain, particularly 
as the trade-wind blew fresh in our faces, and 
continually drove into our eyes particles of sand. 
This part of our journey was unusually laborious, 
not only from the heat of the sun and the reflec¬ 
tion from the lava, but also from the unevenness 
of its surface, which obliged us constantly to tread 
on an inclined plane, in some places as smooth 
and almost as slippery as glass, where the greatest 
caution was necessary to avoid a fall. .Frequently 
