thought bitterly. As nice as the discovery that there was no fuel for
the equipment here. He spent an hour rigging up a portable saw to use in
attempting to cut off a smaller piece of the sky, and then saw the
motor burn out when he switched it on. It turned out that all
electricity here was d.c., conjured up by commanding the electrons in a
wire to move in one direction, and completely useless with a.c. motors.
It might have been useful for welding, but there was no electric torch.

"'Tis obviously not a thing of reason," Garm told him severely. "If the
current in such a form moves first in one direction and then in the
other, then it cancels out and is useless. No, you must be wrong."

As Dave remembered it, Tesla had been plagued by similar doubts from
such men as Edison. He gave up and settled finally for one of the native
welding torches, filled with a dozen angry salamanders. The flame or
whatever it was had enough heat, but it was hard to control. By the time
he learned to use it, night had fallen, and he was too tired to try
anything more. He ate a solitary supper and went to sleep.

During the next three days he learned a few things the hard way,
however. In spite of Garm's assurance that nothing could melt the sky,
he found that his sample would melt slowly under the heat of the torch.
In the liquid state, it was jet black, though it cooled back to complete
transparency. It was also without weight when in liquid form--a fact he
discovered when it began rising through the air and spattering over
everything, including his bare skin. The burns were nasty, but somehow
seemed to heal with remarkable speed. Sersa Garm was impressed by the
discoveries, and went off to suck his thumbs and brood over the new
knowledge, much to Dave's relief.