While darts and stones were showered upon the causeway from the walls, vessels attacked it from both harbors, filled with archers and slingers, who drove the workmen back. Tyre was jubilant. Alexander, she thought, must now surely abandon his foolish enterprise.
Work on the causeway was indeed halted for a time, but only long enough to permit the Macedonians to contrive means of defence. Two great towers were built and pushed out to the end of the mole. These were tall enough to dominate the wall. They were provided with catapults and ballistæ, with which to answer and silence those of the Tyrians, and were manned by soldiers, who from their height were able to reach the decks of the triremes that were sent to annoy them. For further protection, palisades of timber and movable breastworks were constructed on the mole, and pushed forward as it advanced.
Work was resumed, and the long causeway crept nearer and nearer to the city. By order of the council, under cover of night, sponge and pearl divers were sent to the mole in small vessels. With cords in their hands they plunged into the water and fastened them to the foundation stones of the mole, which the crews on board the boats pulled away.
But in spite of all these devices, the mole continued to lengthen.
Still the Tyrians remained confident. The council hit upon a plan to destroy the towers, and when all was ready the people flocked to the walls to witness its execution. Artemisia and Thais watched from the roof, where, day after day, for weeks, they had counted the inches of progress made on the mole and calculated how long it would be before the structure could reach the wall.
"See!" cried Artemisia. "They are going to try to burn the towers."
An old transport, that had been used for carrying horses, emerged clumsily from the Sidonian Harbor, towed between two triremes. The wide deck was heaped with dry wood, which had been saturated with bitumen and intermixed with straw. From the yards of the masts caldrons filled with sulphur, naphtha, and oil were suspended by chains. Upon the deck stood rows of naked men, each holding in his hand a blazing torch.
Slowly and laboriously the ship was guided through the choppy sea to a point directly to windward of the end of the mole. A strong northwest breeze sang through her rigging, and her stern had been filled with ballast until her bow stood almost out of the water. Sailors went aloft and set two small sails to give her headway. The triremes cast off, and she swam straight for the northern tower.
The two women had watched the preparations with the most intense excitement. As the fire-ship neared the mole, gathering speed as she went, they saw a volley of huge stones shoot from the towers in her direction.
"They are trying to sink her," Thais said breathlessly.