CHAPTER XIX.
GEOLOGICAL STUDIES IN SITU Next day, Tuesday, June 30, at 6 a.m., the descent began again.
We were still following the gallery of lava, a real natural staircase, and as gently sloping as those inclined planes which in some old houses are still found instead of flights of steps.

And so we went on until 12.17, the, precise moment when we overtook Hans, who had stopped.
"Ah! here we are," exclaimed my uncle, "at the very end of the chimney." I looked around me.

We were standing at the intersection of two roads, both dark and narrow.

Which were we to take?
This was a difficulty.
Still my uncle refused to admit an appearance of hesitation, either before me or the guide; he pointed out the Eastern tunnel, and we were soon all three in it.
Besides there would have been interminable hesitation before this choice of roads; for since there was no indication whatever to guide our choice, we were obliged to trust to chance.
The slope of this gallery was scarcely perceptible, and its sections very unequal.

Sometimes we passed a series of arches succeeding each other like the majestic arcades of a gothic cathedral.