egular tallow-wax skins, blown up and weighted at
one end so that they would float upright. He yelled into the intercom,
and one was chucked overboard ahead. A moment later, I saw it bobbing
away astern of us. I put my face into the sight-mask, caught it,
centered the cross hairs, and squeezed. The gun gave a thunderclap
and recoiled past me, and when I pulled my face out of the mask, I saw
a column of water and spray about fifty feet left and a hundred yards
over.

"You won't put any wax in the hold with that kind of shooting," Tom
told me.

I fired again. This time, there was no effect at all that I could see.
The shell must have gone away over and hit the water a couple of miles
astern. Before Tom could make any comment on that shot, I let off
another, and this time I hit the water directly in front of the
bobbing wax skin. Good line shot, but away short.

"Well, you scared him, anyhow," Tom said, in mock commendation.

I remembered some of the comments I'd made when I'd been trying to
teach him to hit something smaller than the target frame with a
pistol, and humbled myself. The next two shots were reasonably close,
but neither would have done any damage if the rapidly vanishing skin
had really been a monster. Tom clucked sadly and slapped in another
clip.

"Heave over another one," he called. "That monster got away."

The trouble was, there were a lot of tricky air currents along the
surface of the water. The engines were running on lift to match
exactly the weight of the ship, which meant that she had no weight at
all, and a lot of wind resistance. The drive was supposed to match the
wind speed, and the ship was supposed to be kept nosed into the wind.
A lot of that is automatic, but it can't be made fully so, which means
that the pilot has to do considerable manual correcting, and no human
alive can do that perfectly. Joe Kivelson or Ramon Llewellyn or
whoever was at the controls was doing a masterly job, but that fell
away short of giving me a stable gun platform.

I caught the second target as soon as it bobbed into sight and slammed
a shell at it. The explosion was half a mile away, but the shell
hadn't missed the target by more than a few yards. Heartened, I fired
again, and that shot was simply dreadful.

"I know what you're doing wrong," Tom said. "You're squeezing the
trigger."

"_Huh_?"

I pulled my face out of the sight-mask and looked at him to see if he
were exhibiting any other signs of