Expecting every instant that Wirz would turn around and order me to come to the desk to show my handwriting, hastily and furtively wiped my hand on the back of my shirt and watched Wirz with as innocent an expression as a school boy assumes when he has just flipped a chewed paper wad across the room.
Wirz was still engrossed in his writing, and did not look around.

I was emboldened to reach down for another handful.

This was also successfully transferred, the hand wiped off on the back of the shirt, and the face wore its expression of infantile ingenuousness.

Still Wirz did not look up.

I kept dipping up handful after handful, until I had gotten about a quart in the left hand pocket.