In chapter ten, there is clearly a storm brewing not just in terms of the weather but in terms of the final bounds of civilization being broken. In order for this to happen, it is fitting that Jack's attempts to gain more power should be successful.
Ralph and Piggy have come to the party after some members of their group have already gone. The pull of the meet and the "party" is strong and boys are already starting to want to be in Jack's tribe. Once they arrive, Jack actually orders that meat be brought to them and continues to order around the other boys getting water and whatever else he wants. He is showing over and over again his power and control.
When there is a pitched conflict about who is in charge and Ralph threatens to call a meeting, Jack tells him that no one will go and then when the kids get nervous after the rain starts, he orders them to dance. It is in this powerful ritual of violence where the boys feel some power to fight back against the beast that Jack finds his power and it helps to draw the boys to him.