klin incessantly added fuliginous matter. These clouds, which rolled
heavily in the air, were evidently composed of heterogeneous substances.
It was not alone from the volcano that they derived their strange
opacity and weight. Scoriae, in a state of dust, like powdered
pumice-stone, and grayish ashes as small as the finest feculae, were
held in suspension in the midst of their thick folds. These ashes are so
fine that they have been observed in the air for whole months. After
the eruption of 1783 in Iceland for upwards of a year the atmosphere was
thus charged with volcanic dust through which the rays of the sun were
only with difficulty discernible.

But more often this pulverized matter falls, and this happened on the
present occasion. Cyrus Harding and Ayrton had scarcely reached the
corral when a sort of black snow like fine gunpowder fell, and instantly
changed the appearance of the soil. Trees, meadows, all disappeared
beneath a covering several inches in depth. But, very fortunately,
the wind blew from the northeast, and the greater part of the cloud
dissolved itself over the sea.

"This is very singular, Captain Harding," said Ayrton.

"It is very serious," replied the engineer. "This powdered pumice-stone,
all this mineral dust, proves how grave is the convulsion going forward
in the lower depths of the volcano."

"But can nothing be done?"

"Nothing, except to note the progress of the phenomenon. Do you,
therefore, Ayrton, occupy yourself with the necessary work at the
corral. In the meantime I will ascend just beyond the source of Red
Creek and examine the condition of the mountain upon its northern
aspect. Then--"

"Well, Captain Harding?"

"Then we will pay a visit to Dakkar Grotto. I wish to inspect it. At any
rate I will come back for you in two hours."

Ayrton then proceeded to enter the corral, and, while awaiting the
engineer's return, busied himself with the musmons and goats which
seemed to feel a certain uneasiness in presence of these first signs of
an eruption.

Meanwhile Cyrus Harding ascended the crest of the eastern spur, passed
Red Creek, and arrived at the spot where he and his companions had
discovered a sulphurous spring at the time of their first exploration.

How changed was everything! Instead of a single column of smoke he
counted thirteen, forced through the soil as if violently propelled by
some piston. It was evident that the crust of the earth was subjected
in this par