Nero’s Baths, the ruins of Baiae, the Temple of Serapis; Cumae, where the Cumaen Sybil interpreted the oracles, the Lake Agnano, with its ancient submerged city still visible far down in its depths—­these and a hundred other points of interest we examined with critical imbecility, but the Grotto of the Dog claimed our chief attention, because we had heard and read so much about it.  Every body has written about the Grotto del Cane and its poisonous vapors, from Pliny down to Smith, and every tourist has held a dog over its floor by the legs to test the capabilities of the place.  The dog dies in a minute and a half—­a chicken instantly.  As a general thing, strangers who crawl in there to sleep do not get up until they are called.  And then they don’t either.  The stranger that ventures to sleep there takes a permanent contract.  I longed to see this grotto.  I resolved to take a dog and hold him myself; suffocate him a little, and time him; suffocate him some more and then finish him.  We reached the grotto at about three in the afternoon, and proceeded at once to make the experiments.  But now, an important difficulty presented itself.  We had no dog.

Ascent of Vesuvius—­continued.

At the Hermitage we were about fifteen or eighteen hundred feet above the sea, and thus far a portion of the ascent had been pretty abrupt.  For the next two miles the road was a mixture—­sometimes the ascent was abrupt and sometimes it was not:  but one characteristic it possessed all the time, without failure—­without modification—­it was all uncompromisingly and unspeakably infamous.  It was a rough, narrow trail, and led over an old lava flow—­a black ocean which was tumbled into a thousand fantastic shapes—­a wild chaos of ruin, desolation, and barrenness—­a wilderness of billowy upheavals, of furious whirlpools, of miniature mountains rent asunder—­of gnarled and knotted, wrinkled and twisted masses of blackness that mimicked branching roots, great vines, trunks of trees, all interlaced and mingled together:  and all these weird shapes, all this turbulent panorama, all this stormy, far-stretching waste of blackness, with its thrilling suggestiveness of life, of action, of boiling, surging, furious motion, was petrified!—­all stricken dead and cold in the instant of its maddest rioting!—­fettered, paralyzed, and left to glower at heaven in impotent rage for evermore!

Finally we stood in a level, narrow valley (a valley that had been created by the terrific march of some old time irruption) and on either hand towered the two steep peaks of Vesuvius.  The one we had to climb —­the one that contains the active volcano—­seemed about eight hundred or one thousand feet high, and looked almost too straight-up-and-down for any man to climb, and certainly no mule could climb it with a man on his back.  Four of these native pirates will carry you to the top in a sedan chair, if you wish it, but suppose they were to slip