Of course they rode to the fortress and wandered through its gloomy, impressive galleries, seeing little of the armament because visitors are barred from the real fortifications.  The fortress did not seem especially impregnable and was, taken altogether, a distinct disappointment to them; but the ride through the town in the low basket phaetons was wholly delightful.  The quaint, narrow streets and stone arches, the beautiful vistas of sea and mountain, the swarthy, dark-eyed Moors whose presence lent to the town an oriental atmosphere, and the queer market-places crowded with Spaniards, Frenchmen, Jews and red-coated English soldiers, altogether made up a panorama that was fascinating in the extreme.

But their stay was short, and after a rush of sightseeing that almost bewildered them they returned to the ship breathless but elated at having “seen an’ done,” as Uncle John declared, their first foreign port.

And now through waters so brightly blue and transparent that they aroused the girls’ wonder and admiration, the good ship plowed her way toward the port of Naples, passing to the east of Sardinia and Corsica, which they viewed with eager interest because these places had always seemed so far away to them, and had now suddenly appeared as if by magic directly before their eyes.

Patsy and the big whiskered captain had become such good friends that he always welcomed the girl on his own exclusive deck, and this afternoon she sat beside him and watched the rugged panorama slip by.

“When will we get to Naples?” she asked.

“To-morrow evening, probably,” answered the captain.  “See, it is over in that direction, where the gray cloud appears in the sky.”

“And what is the gray cloud, Captain?”

“I do not know,” said he, gravely.  “Perhaps smoke from Vesuvius.  At Gibraltar we heard that the volcano is in an ugly mood, I hope it will cause you no inconvenience.”

“Wouldn’t it be fine if we could see an eruption!” exclaimed the girl.

The captain shook his head.

“Interesting, perhaps,” he admitted; “but no great calamity that causes thousands of people to suffer can be called ‘fine.’”

“Ah, that is true!” she said, quickly.  “I had forgotten the suffering.”

Next morning all the sky was thick with smoke, and the sun was hidden.  The waters turned gray, too, and as they approached the Italian coast the gloom perceptibly increased.  A feeling of uneasiness seemed to pervade the ship, and even the captain had so many things to consider that he had no time to converse with his little friend.

Signor Valdi forsook his deck chair for the first time and stood at the rail which overlooked the steerage with his eyes glued to the grim skies ahead.  When Uncle John asked him what he saw he answered, eagerly: 

“Death and destruction, and a loss of millions of lira to the bankrupt government.  I know; for I have studied Etna for years, and Vesuvio is a second cousin to Etna.”