s could spot all
sorts of minute shortcomings was a great help. And I was hearing the old
tongue and talking of the old things every day, and truly that went far
to take the clutter out of my mind. I was no longer so lonely that I
couldn't think properly.

On the sixteenth day I covered a piece of paper with tiny mathematical
symbols and handed it to Keech. "Here is your equation," I said. "It
will enable you to know your thrust at any given moment, under any
circumstances, in or out of gravity, and under all conditions of
friction and combustion."

"Thank you, Mr. Houlihan," said Keech. All his people had gathered in a
loose circle, as though attending a rite. They were all looking at me
quietly.

"Mr. Houlihan," said Keech, "you will not be forgotten by the
leprechauns. If we ever meet again, upon another world perchance, you'll
find our friendship always eager and ready."

"Thank you," I said.

"And now, Mr. Houlihan," said Keech, "I'll see that a quantity of gold
is delivered to your rooms tonight, and so keep my part of the
bargain."

"I'll not be needing the gold," I said.

Keech's eyebrows popped upward. "What's this now?"

"I'll not be needing it," I repeated. "I don't feel it would be right to
take it for a service of this sort."

"Well," said Keech in surprise, and in some awe, too, "well, now, musha
Lord help us! 'Tis the first time I ever heard such a speech from a
mortal." He turned to his people. "We'll have three cheers now, do you
hear, for Mr. Houlihan--friend of the little people as long as he shall
live!"

And they cheered. And little tears crept into the corners of some of
their turned-up eyes.

We shook hands, all of us, and I left.

* * * * *

I walked through the park, and back to the nuclear propulsion center. It
was another cool, green morning with the leaves making only soft noises
as the breezes came along. It smelled exactly like a wood I had known in
Roscommon.

And I lit my pipe and smoked it slowly and chuckled to myself at how I
had gotten the best of the little people. Surely it was not every mortal
who could accomplish that. I had given them the wrong equation, of
course. They would never get their spaceship to work now, and later, if
they tried to spy out the right information I would take special
measures to prevent it, for I had the advantage of being able to see
them.

As for our own rocket ship, it should be well on its way by ne