Then, an apprentice mage applied a simple, low-power, curative spell of intensely purple light to it, until its surface fused into a single, inflexible piece. It would be tipped onto its longest side, the bladder deflated and pulled out, and there was your hull. Total cost, almost nothing, except for the spellwork, but that was kept a very dear state secret. The result was more waterproof than treated and varnished wood, light enough that two men could carry a hull with ease, tough enough to take hard collisions in the water, easy to patch if it was holed, and it could be made in any shape you liked. On the east coast, they made deeper-drafted, keeled, seagoing boats in addition to barges. In Lyranhold, they were known to make cottage roofs as well. The practical size-limit was right about the length of three wagons; after that they needed some internal ribbing and proper keels to keep from buckling over time, especially in seagoing vessels.

The resulting forms weren’t ideal as roofs, mostly because while they kept out the weather, they did little to keep out the heat of summer nor the cold of winter. In order to be made into barges people could live comfortably in, or into roofs for more than a shepherd’s hut, they needed to be insulated, and that added considerably to the cost. One lesser mage and a crew of helpers could produce as many as four or five plain hulls a day, once the production was started.

They had all sorts of molds here, from rowboats to living barges where entire families could make a comfortable home. Mostly, though, what they produced were cargo barges. The main difference between the cargo barges and the living barges was that no one bothered to cut too many windows into the angled sides of the cargo barges except at the end, where there would be a small cabin for the operator.

There were molded loops at either end. Several barges could be roped together to form a train, and one or two Tow-Beasts hitched to the front loop of the front barge were sufficient to haul the entire thing along, heavily loaded.

It probably never entered the Emperor’s mind, but those three workshops were the main reason commerce flowed so easily and cheaply, if a little slowly, within the Empire. While Imperial roads were good, the network of canals was excellent. There were Gates at intervals along every canal as well as locks to lift the barges over elevation changes. Generally, anything that needed transportation went by barge for all but the last few leagues, or within a large city.