And many are the caravans that perish in its eddies.
To escape this dust, which might have interfered with the working of the screws, the "Albatross" shot up some six thousand feet into a purer atmosphere.
And thus vanished the Persian frontier and the extensive plains.

The speed was not excessive, although there were no rocks ahead, for the mountains marked on the map are of very moderate altitude.

But as the ship approached the capital, she had to steer clear of Demavend, whose snowy peak rises some twenty-two thousand feet, and the chain of Elbruz, at whose foot is built Teheran.
As soon as the day broke on the 2nd of July the peak of Demavend appeared above the sandstorm, and the "Albatross" was steered so as to pass over the town, which the wind had wrapped in a mantle of dust.
However, about six o'clock her crew could see the large ditches that surround it, and the Shah's palace, with its walls covered with porcelain tiles, and its ornamental lakes, which seemed like huge turquoises of beautiful blue.
It was but a hasty glimpse.

The "Albatross" now headed for the north, and a few hours afterwards she was over a little hill at the northern angle of the Persian frontier, on the shores of a vast extent of water which stretched away out of sight to the north and east.
The town was Ashurada, the most southerly of the Russian stations.
The vast extent of water was a sea.

It was the Caspian.
The eddies of sand had been passed.