The other guy says "No way".

The first guy walks around to the back of the camel with two bricks, reaches in between the camel's legs and crashes the bricks together. The camel jumps 30 feet in the air.

A couple of days later the first guy says to the second guy, "I bet you I can make that camel nod his head yes, then shake his head no."

The second guy says, "You got me last time, but there's no way you can make that dumb animal nod his head yes then shake it no."

The first guy takes the same two bricks, walks around to the front of the camel, holds up the bricks and says, "Remember what I did last time?". (Camel nods). "Want me to do it again?"