e of the Fane. Saw Lonnie turn toward them,
the dark line disappearing from waist to top as if it had never been.

Once more the different-whiteness moved. Toward them. Edging for the
back wall to skirt around them; one limb-shape fumbling in the palm of
the other.

"No you don't!" McGillis, ahead of Jason, yelled, his howl drowned in
the smacking crack of his pistol.

There seemed to be a waver in the different-whiteness. A small black dot
appeared against it; hung briefly, apparently unsupported, in the air;
then the undistorted bullet dropped inertly to the floor.

"You _still_ won't!" McGillis hurled himself, shoulders low and legs
driving, at the shape. Two feet from it, he rebounded sharply, trod on
the rolling bullet, went down, his head splatting dully against the
marble floor.

Holland grunted. Crouched to leap. Thrust his disarmer high, ready to
snap into line.

"Hold it!" Jason commanded. Silently, eyelids barely separated to endure
the dazzle, he stared at the different-whiteness that confronted him. "I
made it this time, Lonnie," he called. "Caught up with you-- No!" His
arm flung out, startling him with the feel of his disarmer now oddly in
his hand.

"Don't move!"

The white-within-white's limb-shapes moved up, the hand-ends one over
the other. Through the minute spaces the overlapping fingers left,
glimpses of a thin dark line appeared. The hood was open a trifle at
mouth level, and from the opening Lonnie's voice emerged, sifting
through the protecting screen of gloves. "You can't see me! You
_can't_!"

"No? Take one step sideways. Just _one_! Stop!"

The different-whiteness had moved, and Holland had moved with it;
crouching now, alertly motionless, in his new position. Jason changed
the angle of his own facing. "Now do you think we can't see you?"

"But ... but how!"

"Your albedo is showing," Jason chuckled harshly. "You never would take
the trouble to learn the _how_ of anything, Lonnie. Sure, your damned
disguise is the same color as the marble. Maybe even exactly the same.
But the material is different, and the surface texture; it doesn't have
the same degree or quality of reflectivity to incident light that marble
does!

"Eighty years ago, even the commercial photographers knew about
albedo--one of 'em made a picture of a cat, white on white. I told you
about the reflectivity in your stereo cube. But you wouldn't listen,
Lonnie, would you?" Jason let out a bursting peal of laugh