"A change of this sort is unusual," said the gentleman who had told them of the seizure of Perim, "but when it does come it is very grateful. Only in January or February is the Red Sea anything but hot; the winds blow from the sandy desert, or from the region of the equator, and sometimes it seems as though you were in a furnace. From December to March the thermometer averages 76°, from thence to May it is 87°, and through the four or five months that follow it is often 100°. I have frequently seen it 110° in the cabin of a steamer, and on one occasion, when the simoom was blowing from the desert, it was 132°. Steamers going north when the south wind is blowing find themselves running just with the wind, so that they seem to be in a dead calm; in such cases they sometimes turn around every ten or twelve hours and run a few miles in the other direction, so as to let the wind blow through the ship and ventilate it as much as possible. The firemen are Arabs and negroes, accustomed all their lives to great heat, but on almost every voyage some of them find the temperature of the engine-room too severe, and die of suffocation." [Illustration: VIEW IN JEDDAH, ON THE RED SEA.] Our friends passed by Jeddah, the port of Mecca, and from the deck of the steamer the white walls and towers of the town were distinctly visible. Frank and Fred would have been delighted to land at Jeddah and make a pilgrimage to Mecca, but the Doctor told them the journey was out of the question, as no Christian is allowed to enter the sacred city of the Moslems, and the few who had ever accomplished the feat had done so at great personal risk. [Illustration: CAPTAIN BURTON IN NATIVE DRESS.] "The first European who ever went there was Burckhardt, in 1814," said Dr. Bronson. "He prepared himself for his travels by studying the Arabic language, and went in the disguise of an Arab merchant, under the name of Sheikh Ibrahim ibn Abdallah. Then he travelled through Syria, Asia Minor, and Egypt for several years, and became thoroughly familiar with the customs of the people, so that he was able to pass himself successfully as a learned Moslem. Captain Burton went to Mecca in 1852, and since his time the city has been visited by Maltzan, Palgrave, and two or three others. Captain Burton followed the example of Burckhardt and wore the Arab dress; he spoke the language fluently, but in spite of this his disguise was penetrated while he was returning to Jeddah, and he was obliged to flee from his companions and travel all night away from the road till he reached the protection of the seaport." "What would have happened if he had been found out?" Frank inquired.