They went hunting, they set snares, they swam in the river or in the cold waters of the fjord. Somerled had not forgotten what Eyvind had taught him, and he learned more. He would never be a warrior, that much was clear. With his new tricks learned from Eirik, and his superior size and strength, Eyvind was as far beyond his friend in physical skills as a master craftsman is beyond the rawest apprentice. But at least, under his tutelage, Somerled learned to defend himself. If he ever had to live rough, he would be able to find his own food and shelter. They built a platform together in the upper branches of a sturdy oak, a secret refuge that could be reached only by means of a knotted rope. The floor was of lashed poles, the walls of wattles, the roof open to the stars. It was very high. Once, during the construction, Somerled had slipped and nearly fallen; he clung by one hand, his fingers all that prevented a rapid descent to instant oblivion on the forest floor. Eyvind had managed to grip his arms and haul him to safety. Near sunset, as they sat on their high perch listening to the cries of homing birds, Eyvind saw Somerled scratching something on the bark with his hunting knife.

“What are you doing?” he asked. “You’ll blunt the edge.”

Somerled did not answer. The knife was making a neat, irregular pattern of vertical lines and slanting cross-strokes, like a row of little trees, each with one or two or three branches.

“Somerled? What is that?”

The steady movement of the knife continued. Somerled spoke without turning.

“It says here, Two brothers made this house. Somerled carved these runes.”

Eyvind’s jaw dropped. “You mean, you can write?” he breathed in astonishment.

“I haven’t been wasting my time,” Somerled said casually, incising a neat pair of parallel lines against one small upstroke. “A man needs certain skills to advance in life. This is one of them. I can read, too. But this is not everyday writing, Eyvind. Here, let me show you.”

Patiently he went along the line of tidy markings, explaining what each meant, and why. “They are not ordinary runes, you understand, but another kind, a secret kind. Even among scholars, few understand them. The branches are the clue, a sort of pointer…”

His explanation was careful and slow, but after a while he stopped. Looking at Eyvind, he did not smile, exactly; a real smile from Somerled was a rare event. But his expression softened.

“I’m sorry,” confessed Eyvind ruefully. “I just don’t understand.” It was beginning to come to him that perhaps his friend was very clever indeed, so clever that Eyvind might never quite comprehend him.