ent of any frequency they chose by use of a
special collector apparatus. They could release radiant energy in almost
any quantity they desired, in any wave-length, from the longest radio to
the incredibly hard cosmics. The electrical power they could measure
accurately and easily by simple voltmeters and ammeters. But radiant
energy was another thing. When it passed all hitherto known bonds, it
would simply fuse any instrument they might use to measure it.

But they knew the power they generated. In one split second they had
burst the energy bonds of a tiny bit of steel and that energy had glared
briefly more hotly than the Sun.

"Greg," he said, "it isn't often you can say that any event was the
beginning of a new era. You can with this--the era of unlimited power.
It kind of scares me."

Up until a hundred years ago coal and oil and oxygen had been the main
power sources, but with the dwindling of the supply of coal and oil, man
had sought another way. He had turned back to the old dream of snatching
power direct from the Sun. In the year 2048 Patterson had perfected the
photo-cell. Then the Alexanderson accumulators made it possible to pump
the life-blood of power to the far reaches of the System, and on Mercury
and Venus, and to a lesser extent on Earth, great accumulator power
plants had sprung up, with Interplanetary, under the driving genius of
Spencer Chambers, gaining control of the market.

The photo-cell and the accumulator had spurred interplanetary trade and
settlement. Until it had been possible to store Sun-power for the
driving of spaceships and for shipment to the outer planets, ships had
been driven by rocket fuel, and the struggling colonies on the outer
worlds had fought a bitter battle without the aid of ready power.

Coal and oil there were in plenty on the outer worlds, but one other
essential was lacking ... oxygen. Coal on Mars, for instance, had to
burned under synthetic air pressures, like the old carburetor. The
result was inefficiency. A lot of coal burned, not enough power
delivered.

Even the photo-cells were inefficient when attempts were made to operate
them beyond the Earth; that was the maximum distance for maximum Solar
efficiency.

Russ dug into the pocket of his faded, scuffed leather jacket and hauled
forth pipe and pouch. Thoughtfully he tamped the tobacco into the bowl.

"Three months," he said. "Three months of damn hard work."

"Yeah," agreed Wilson, "we sure have wor