"Well, what else, then? I know we've been concentrating on coastal warships and harbor defense, but I need a cutter that can cover great distances on open water fast. It can't carry a lot of rowers. I don't want it putting in to shore every day or two. It should keep on the move every hour, even traveling at night."
"That's a challenge. What is it to carry?"
"Aside from sustenance for the crew, just information. I want the water equivalent of a horseback courier. It's to keep me in contact with an army that will be constantly on the march."
Archelaus nodded, stroking his small beard. "I see. How intriguing. And how fortuitous. Come with me."
The two Romans followed the man. He led them past a barge-like boat, its deck holding a number of the flying machines and equipped with a system of towering masts from which to launch them. Other ships were fitted with paddle wheels, with varying arrangements of cranks and treadmills to drive them. They came to a pier to which were fastened several small vessels featuring a bewildering array of masts, yards and sails.
"Here," Archelaus informed them, "we experiment with new sail plans and rigging systems."
"And how do these affect performance?" Flaccus asked.
"In many ways, we have found. We've been using a single, large, square sail spread before the mast since the Argo. With a wind astern, it moves the ship well. But only if the wind is from almost directly astern."
"That much we know from our admittedly limited seafaring experience," Flaccus said. "How may it be done otherwise?"
"Look at this." They came to a small, narrow vessel. It was no more than forty feet long and had the familiar, single mast. But its yard, instead of being set square across the length of the vessel, slanted across it. "You can't get a good idea from this; you'll have to see it sailing. It's copied from a type of ship used off the coast of India. One of our skippers brought one back this season, along with some Indian sailors to show us how it is employed."
"What is its advantage?" Marcus wanted to know.
"It can make use of a wind that is not blowing from directly astern. With skill, using both sail and steering oar, it can even make use of a wind that comes from slightly ahead."
"Sail into a headwind?" Flaccus said. "That makes no sense."
"As I said, you'll have to see it demonstrated. It takes a skilled crew, but it needs only five or six men. We built this one small, because it was to be used just for experiment with the sail. There's no cargo space and precious little for the crew. But it may be ideal for your purpose. If all you want is a courier, this is it."
"Show us," Marcus said.
And so the little vessel set out with its small crew and two Romans, first in the sheltered waters of the harbor, then past Point Lochias into the open sea. All morning and into the afternoon the shipmaster, a hard-bitten old pirate from Cilicia, and his crew of strange men from fabled India, demonstrated the bizarre sail and its seemingly unnatural capabilities. It proved to be triangular, and when set, its extremely long yard almost touched the bow rail on one side of the ship, while the opposite end towered above the stern on the opposite side. It was huge in proportion to the vessel, and the Romans remarked upon this.
"It's a lot of mast and sail for such a small ship," the master agreed. "She has to be heavily ballasted to keep her from capsizing. Her bottom's filled with lead bricks to keep her upright."
He showed them how, by a combination of slanting the sail and working the steering oar, the ship could take advantage of a less-than-favorable wind. After taking the wind from one side for a while, at the master's order the crew performed a breathtaking maneuver, collapsing the sail and slewing the long yard up and across to hang on the other side of the mast and take the same wind from that side. The ship changed direction, but its general trend was still in the direction desired.
"You see?" the skipper said. "When the wind's not right, you travel in a series of zigzags to keep moving ahead. It's not as fast as with a stern wind, but it beats sitting on shore and sacrificing rams for one."
"What about a wind from directly ahead?" Marcus asked.
"Not much you can do about that," the skipper admitted. "This sail's clever, but it's not magical. Still, if you want to get from one end of the sea to the other and you don't want to feed a lot of oarsmen doing it, this rig will beat anything else afloat."
By the time they returned to the harbor, Marcus had decided. The little vessel would be the first of his new fleet of courier craft. As soon as he set foot to the pier, he was bellowing for the master shipbuilder, the harbormaster and the ship philosopher. He said that he wanted twenty of the ships for a start, and training of the crews was to begin immediately, that very day. He named the little ship Hermes. There was no argument. Functionaries and workmen had grown accustomed to the peremptory ways of the Romans.