"Not at all," said Mr. Griggs; "the khat is brought into town every morning about eleven o'clock by long caravans of camels which proceed from the khat farms along the mountain slopes. Long before these camels appear in the valley, with a bundle of khat swung on each side of the beasts, messengers on fleeter camels have brought the tidings of approach. From the shelters of the shops, so silent except just now, cheerful cries break out; the streets are filled with Arabs who sing joyfully; tikka gharries rattle madly by, whips waving and turbans awry; there are flashes of color from rich men's gowns and the sounds of their clicking oryx-hide sandals as they rapidly strike the stony pavements; there is a continual blunt clatter from the tom-toms in the hands of long-gowned fellows. They are all going to the market where the khat will soon arrive, each one anxious to have first choice and get the best bargain. There they will bicker with the khat traders for an hour sometimes, then in will come the despised hadjis, the venders of firewood, who will buy up for a few pice the scraps which remain." This was all very interesting to the flyers, but it was high time to hurry back and resume their flight; so, restraining their impulse to ask more questions or investigate the attractions of the town, they bought their supplies, and returned with the American minister to the landing-field. Ten minutes later the Sky-Bird was mounting easily up into the sky, viewed by hundreds of shouting Arabs. It was good-bye to Persia now. Looking at his watch, Paul, at the throttle, saw that it was nine-fifty. They were leaving Aden only fifty minutes behind schedule. That was not at all bad; but it was not pleasant to think that their rivals were still ahead of them. And two hours was a pretty stiff lead. They were not long in passing over the hills to the south, and then headed eastward out over the elongated gulf. Looking back, John saw the sandhills by the sea glistening in the bright sunlight like mounds of gold-dust. Every leaf and stem in the scrub stood out in black and silver filigree; and euphorbias and adeniums, gouty and pompous above the lower growths, seemed like fantasies of gray on a Japanese screen covered with cerulean velvet. It was their last sight of Persia, and one not soon to be forgotten. Our friends now settled down for a long hop, for they would have to fly all day and all night before reaching Colombo. After a while they sighted Socotra, the little isle off the coast of Cape Guardafui, from whence comes most of the world's supply of frankincense; then leaving its rocky shores behind them they cut straight across the Persian Sea, braving whatever tropical storm might arise.